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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Trattamento radioterapico ipofrazionato ad alte dosi del carcinoma prostatico con tecnica ad intensità modulata (IMRT) guidata dalle immagini (IGRT) / Hypofractionated high-dose radiation therapy for prostate cancer with intensity-modulated and image-guided radiotherapy (IMRT-IGRT)

Micucci, Marco <1979> 16 May 2014 (has links)
Obiettivo: valutare la tossicità ed il controllo di malattia di un trattamento radioterapico ipofrazionato ad alte dosi con tecnica ad intensità modulata (IMRT) guidata dalle immagini (IGRT) in pazienti affetti da carcinoma prostatico a rischio intermedio, alto ed altissimo di recidiva. Materiali e metodi: tutti i pazienti candidati al trattamento sono stati stadiati e sottoposti al posizionamento di tre “markers” fiduciali intraprostatici necessari per l’IGRT. Mediante tecnica SIB – IMRT sono stati erogati alla prostata 67,50 Gy in 25 frazioni (EQD2 = 81 Gy), alle vescichette 56,25 Gy in 25 frazioni (EQD2 = 60,35 Gy) e ai linfonodi pelvici, qualora irradiati, 50 Gy in 25 frazioni. La tossicità gastrointestinale (GI) e genitourinaria (GU) è stata valutata mediante i CTCAE v. 4.03. Per individuare una possibile correlazione tra i potenziali fattori di rischio e la tossicità registrata è stato utilizzato il test esatto di Fisher e la sopravvivenza libera da malattia è stata calcolata mediante il metodo di Kaplan-Meier. Risultati: sono stati arruolati 71 pazienti. Il follow up medio è di 19 mesi (3-35 mesi). Nessun paziente ha dovuto interrompere il trattamento per la tossicità acuta. Il 14% dei pazienti (10 casi) ha presentato una tossicità acuta GI G ≥ 2 e il 15% (11 pazienti) ha riportato una tossicità acuta GU G2. Per quanto riguarda la tossicità tardiva GI e GU G ≥ 2, essa è stata documentata, rispettivamente, nel 14% dei casi (9 pazienti) e nell’11% (7 pazienti). Non è stata riscontrata nessuna tossicità, acuta o cronica, G4. Nessun fattore di rischio correlava con la tossicità. La sopravvivenza libera da malattia a 2 anni è del 94%. Conclusioni: il trattamento radioterapico ipofrazionato ad alte dosi con IMRT-IGRT appare essere sicuro ed efficace. Sono comunque necessari ulteriori studi per confermare questi dati ed i presupposti radiobiologici dell’ipofrazionamento del carcinoma prostatico. / Purpose: to evaluate toxicity and control of disease with hypofractionated high-dose intensity-modulated (IMRT) and image guided (IGRT) radiotherapy in patients with intermediate, high and very high risk of prostate cancer. Materials and Methods: patients eligible for treatment were staged and three fiducial "markers" needed for IGRT were implanted in the prostate. It was delivering with SIB- IMRT 67,50 Gy in 25 fractions (EQD2 = 81 Gy) to the prostate, 56,25 Gy in 25 fractions (EQD2 = 60,35 Gy) to the seminal vesicles and 50 Gy in 25 fractions to the pelvic lymph nodes, when irradiated. Gastrointestinal (GI) and genitourinary (GU) toxicity were assessed using CTCAE v. 4.03. Correlation between potential risk factors and toxicity was performed using the Fisher's test and disease-free survival was calculated using the Kaplan-Meier method. Results: seventy-one patients were evaluated. The mean follow-up was 19 months (3-35 months). No patient had to discontinue treatment for acute toxicity. 14% of patients (10 cases) presented acute GI G ≥ 2 and 15% (11 patients) reported acute toxicity GU G2. Regarding the late toxicity GI and GU G ≥ 2, it has been detected, respectively, in 14% (9 patients) and 11% of cases (7 patients). There was no incidence of any acute or late toxicity G4. No risk factor correlated with toxicity. The disease-free survival at 2 years was 94%. Conclusions: hypofractionated high-dose IMRT-IGRT radiotherapy appears to be safe and effective. However, further studies are needed to confirm these data and the radiobiological bases of hypofractionated radiotherapy of prostate cancer.
72

Partial Discharge Phenomena in Converter and Traction Transformers: Identification and Reliability

Azcarraga, Carlos <1973> 11 March 2014 (has links)
After the development of power electronics converters, the number of transformers subjected to non-sinusoidal stresses (including DC) has increased in applications such as HVDC links and traction (electric train power cars). The effects of non-sinusoidal voltages on transformer insulation have been investigated by many researchers, but still now, there are some issues that must be understood. Some of those issues are tackled in this Thesis, studying PD phenomena behavior in Kraft paper, pressboard and mineral oil at different voltage conditions like AC, DC, AC+DC, notched AC and square waveforms. From the point of view of converter transformers, it was found that the combined effect of AC and DC voltages produces higher stresses in the pressboard that those that are present under pure DC voltages. The electrical conductivity of the dielectric systems in DC and AC+DC conditions has demonstrated to be a critical parameter, so, its measurement and analysis was also taken into account during all the experiments. Regarding notched voltages, the RMS reduction caused by notches (depending on firing and overlap angles) seems to increase the PDIV. However, the experimental results show that once PD activity has incepted, the notches increase PD repetition rate and magnitude, producing a higher degradation rate of paper. On the other hand, the reduction of mineral oil stocks, their relatively low flash point as well as environmental issues, are factors that are pushing towards the use of esters as transformer insulating fluids. This PhD Thesis also covers the study of two different esters with the scope to validate their use in traction transformers. Mineral oil was used as benchmark. The complete set of dielectric tests performed in the three fluids, show that esters behave better than mineral oil in practically all the investigated conditions, so, their application in traction transformers is possible and encouraged.
73

Análisis de las principales ideas sobre la noción de ruptura difundidas en España durante la transición : simientes para utopías realizables en el mundo actual

Mir Garcia, Jordi 07 February 2014 (has links)
La investigación está centrada en el análisis de propuestas de ruptura que se formularon y se intentaron llevar a la práctica durante el franquismo y la transición en España. Por propuestas de ruptura se entiende aquellas elaboraciones teóricas con voluntad de aplicación que se elaboraron, discutieron, difundieron para romper con lo que el franquismo significaba en el ámbito político, social, cultural, económico... Son propuestas de diferentes tendencias que buscaban construir una nueva sociedad. Se trata de elaboraciones y actuaciones que se desarrollaron, principalmente, entre la década de los sesenta y la de los ochenta protagonizadas por individuos, colectivos, partidos y movimientos sociales. Es un intento de hacer historia de las ideas y de que las ideas atendidas nos permitan pensar en los proyectos que se desarrollaron para romper con el franquismo y construir una sociedad que en mente de las personas que lo intentaron fuera mas libre y justa. / The research focuses on the analysis of the proposals of rupture that were formulated and attempted to implement during the Franco regime and the transition in Spain. Rupture proposals meant are theoretical elaborations willing to develop practice, that were elaborated, discussed and disseminated to break with what Franco meant in the political, social, cultural, economic areas... They are different trends seeking to build a new society. These elaborations and actions were developed mainly between the sixties and the eighties by individuals, groups, parties and social movements. It is an attempt to make history of ideas and that the ideas addressed allow us to think about projects that were developed to break the Franco regime and build a society that in the minds of people who tried it out would be more free and fair.
74

Comercio y diplomacia entre Japón y Filipinas en la era Keichō, 1596-1615

Iaccarino, Ubaldo 12 December 2013 (has links)
Para finales del siglo XVI, Japón y Filipinas establecieron las primeras relaciones diplomático-comerciales, y durante la era Keichō (1596-1615) se planteó el intento de una cooperación entre Madrid y el gobierno de Tokugawa Ieyasu (1598-1616). Esto permitió a los españoles impulsar el trato comercial con Japón favoreciendo la penetración de los misioneros. En esta tesis se detallan las distintas fases del proceso de relaciones diplomático-comerciales y misionales en el contexto de las transformaciones internas de Japón y de sus ambiciones de proyección regional asiática, al margen del sinocentrismo Ming. Se analiza asimismo el contexto de las limitaciones institucionales y legales a la expansión del archipiélago filipino y los distintos factores que condujeron al fracaso de la cooperación hispano-japonesa y a la progresiva desaparición de todo rastro de contactos formales con Japón en el marco de su general política aislacionista adoptada en la tercera década del siglo XVII.
75

Economia i cultura en el primer exili. França, 1939-1940. Les finances de la Generalitat de Catalunya i les residències de Montpeller i Tolosa

Puigarnau Torelló, Xavier 05 December 2014 (has links)
Aquesta tesi doctoral aborda el primer moment d’exili de la Generalitat de Catalunya després de la conquesta del Principat per part de les tropes franquistes. S’ha centrat l’estudi en les finances i organització de la institució catalana a França, considerades eines indispensables per materialitzar la seva estratègia de supervivència en tres àrees bàsiques: assistència als refugiats, foment i conservació de la cultura catalana i sosteniment de les idees polítiques de perfil catalanista republicà. La residència de Montpeller, instituïda per la Generalitat i fomentada especialment pel President Lluís Companys, resultarà una peça clau en la seva estratègia de suport als exiliats, fonamentalment, de perfil polític. Per contrast, la residència de Tolosa, promoguda per intel·lectuals francesos i destinada a docents i professors universitaris exiliats, representa un paradigma de la incapacitat de la Generalitat de Catalunya per portar a terme les iniciatives previstes inicialment. La manca crònica d’un finançament provinent del govern espanyol republicà exiliat, serà una de les principals causes d’aquesta situació. / Esta tesis doctoral aborda el primer momento de exilio de la Generalitat de Catalunya después de la conquista del Principado por parte de las tropas franquistas. El estudio se centra en las finanzas y organización de la institución catalana en Francia, considerándolas indispensables para materializar su estrategia de supervivencia en tres áreas básicas: asistencia a los refugiados, fomento y conservación de la cultura catalana y sostenimiento de las ideas políticas de perfil catalanista republicano. La residencia de Montpellier, instituida por la Generalitat i fomentada especialmente por el Presidente Lluís Companys, resultará una pieza clave en su estrategia de soporte a los refugiados, fundamentalmente, de perfil político. x Por contraste, la residencia de Toulouse, promovida por intelectuales franceses y destinada a docentes y profesores universitarios exiliados, representa un paradigma de la incapacidad de la Generalitat de Catalunya para llevar a cabo las iniciativas inicialmente previstas. La falta crónica de financiación proveniente del gobierno republicano español exiliado, será una de las principales causas de esta situación. / In this doctoral dissertation the author deals with the first chronological stages of the Generalitat de Catalunya exiled in France short after the victory of the General Franco troops over the Republican side of the Spanish Civil War. The main focus is given to the finances and logistics of the Government in exile which are considered vital for their surviving strategy in three main areas: the assistance to the refugees, the preservation and promotion of Catalan culture and ultimately the maintainance of the Republican Catalanist political ideals. The foundation of the Hall of Residents in the city of Montpellier by the Generalitat, and its special promotion by the President Lluís Companys are both considered in this work to be the key factors to explain the Government’s strategy to mainly support political refugees. The Hall of Residents in the city of Toulouse, promoted by French intellectuals and conceived for housing school teachers and university professors was unlikewise a paradigm of the Generalitat inability to lead their initially scheduled purposes. Following this dissertation hypotheses one of the main causes to this historical fact had to be with the continuous lack of financial support from the side of the Spanish Government in exile.
76

Hur genus förmedlas av barn och till barn : En studie om genus i bilderboken som en genre

Hammarström, Alva January 2015 (has links)
Genus är ett begrepp som beskriver hur det socialt och kulturellt är att vara kvinna eller man. Inom litteraturvetenskapen växer intresset för genusinriktade studier där man tittar på hur genus konstrueras i litteraturen. Den här studien undersöker hur genus förmedlas till barn genom en bilderbok. En bilderbok idag är något som är självklart för många men samtidigt oklart. Bilderboken har sin plats på biblioteket och i bokhandeln men det finns inte alla gånger en klar definition av vad bilderböcker är. Syftet med studien är att studera bilderboken som en egen genre och hur en nutida bilderbok kan skildra genus.  Analysen kommer att gå in på de valda författarna och illustratörernas, Pija Lindenbaum och Per Gustavsson, uppbyggnad av en bilderbok. Diskussionen kring analysen kommer att vara genusfokuserad och där kommer flicka mot flicka och pojke mot pojke i Lindenbaum och Gustavssons bilderböcker att sättas emot varandra. Studien visar på att Lindenbaum och Gustavsson är normbrytande bilderboksförfattare som med olika typer av huvudkaraktärer bryter normen.
77

Prestazioni energetico-ambientali di sistemi cogenerativi avanzati e analisi di casi applicativi / Energy and environmental performance assessment of advanced CHP systems and application cases

Valentini, Elisa <1981> 04 June 2014 (has links)
Lo scopo di questa tesi è quello di analizzare dapprima l’impatto ambientale di tali impianti e poi analizzare il contributo effettivo che oggi la tecnologia innovativa dei cicli Rankine organici può dare nella valorizzazione elettrica del calore di scarto di processi industriali, focalizzando l’obiettivo principalmente sulle turbine a gas ed eseguendo un caso di studio in un settore ancora poco esplorato da questa tecnologia, quello Oil&Gas. Dopo aver effettuato il censimento degli impianti a fonti fossili e rinnovabili, cogenerativi e non, presenti in Emilia-Romagna, è stato sviluppato un software chiamato MiniBref che permette di simulare il funzionamento di una qualsiasi centrale termoelettrica grazie alla possibilità di combinare la tecnologia dell’impianto con il tipo di combustibile consentendo la valutazione delle emissioni inquinanti ed i potenziali di inquinamento. Successivamente verranno illustrati gli ORC, partendo dalle caratteristiche impiantistiche e termodinamiche fino ad arrivare alla scelta del fluido organico, fondamentale per le performance del ciclo. Dopo aver effettuato una ricognizione dello stato dell’arte delle applicazioni industriali degli ORC nel recupero termico, verranno eseguite simulazioni numeriche per ricostruire gli ORC ed avere una panoramica il più completa ed attendibile delle prestazioni effettive di questi sistemi. In ultimo verranno illustrati i risultati di un caso di studio che vede l’adozione di recupero mediante ciclo organico in un’installazione esistente del settore Oil&Gas. Si effettuerà uno studio delle prestazione dell’impianto al variare delle pressioni massime e minime del ciclo ed al variare del fluido impiegato al fine di mostrare come questi parametri influenzino non solo le performance ma anche le caratteristiche impiantistiche da adottare. A conclusione del lavoro si riporteranno i risultati relativi all’analisi condotte considerando l’impianto ai carichi parziali ed in assetto cogenerativo. / This work presents a study related with off-shore oil & gas production and processing facilities, where required energy, for electric power, mechanical power and process heat, is mostly produced using gas turbines, as the fuel source (natural gas) is available onsite. Since size and weight of all equipment on an offshore facility are critical, it becomes necessary for the facility engineering team to ensure that all equipment are sized and selected appropriately to obtain better return on the investment. Therefore, any approach which could help in utilizing energy resources effectively will influence the bottom-line of the project, namely reduced capital cost and/or increased return on investment. In this work, one such approach of recovering power and thermal energy through the use of Organic Rankine Cycle system is discussed. A detailed thermo-economic analysis, conducted considering a system with four gas turbines operating, shows that power recovery equivalent to one topping gas turbine is achievable with a suitable working fluid. The analysis presented clearly shows that use of the Organic Rankine Cycle system for waste heat recovery is a technically viable and economically attractive solution for the offshore applications.
78

Les Comissions de la Veritat, un factor de transformació social en comunitats en conflicte: la Comissió de la Veritat i Reconciliació (CVR) sud-africana

Sòria Ortíz, Ferriol 14 January 2013 (has links)
Les Comissions de la Veritat són un instrument de justícia transicional amb potencial de transformació social en societats en conflicte. El disseny de les Comissions i l’itinerari que recorrin condicionen el desenvolupament d’aquest potencial. La recerca fixa els factors de disseny i anàlisi de les comissions i la relació que tenen entre si. Sota aquests paràmetres i com a estudi de cas, s’analitza la Comissió de la Veritat i Reconciliació de Sud-àfrica (CVR). I es fa longitudinalment, analitzant els factors que incideixen en el moment de la seva gestació, desenvolupament, finalització i posteriors actuacions del govern com a resposta a les recomanacions que figuren al seu Informe Final. La CVR esdevé un exemple paradigmàtic del desenvolupament d’aquest potencial transformador i dels riscos que poden portar a que el procés no tingui la força esperada si algun dels factors que el condicionen no es pondera adequadament. / Las Comisiones de la Verdad son un instrumento de justicia transicional con potencial de transformación social en sociedades en conflicto. El diseño de las Comisiones y el itinerario que recorran condicionan el desarrollo de este potencial. La investigación fija los factores de diseño y análisis de las comisiones y la relación que tienen entre sí. Bajo estos parámetros y como estudio de caso, se analiza la Comisión de la Verdad y Reconciliación de Sudáfrica (CVR). Y se hace longitudinalmente, analizando los factores que inciden en el momento de su gestación, desarrollo, finalización y posteriores actuaciones del gobierno como respuesta a las recomendaciones que figuran en su Informe Final. La CVR se convierte en un ejemplo paradigmático del desarrollo de este potencial transformador y de los riesgos que pueden llevar a que el proceso no tenga la fuerza esperada si alguno de los factores que lo condicionan no se pondera adecuadamente.
79

Un arxipèlag invisible: la relació impossible de Sardenya i Còrsega sota nacionalismes, segles XVIII-XX

Farinelli, Marcel A., 1978- 27 November 2013 (has links)
Còrsega i Sardenya, dues illes que disten només 12 km., formen un arxipèlag en el bell mig del Mediterrani occidental. No obstant, van estar dividides al llarg de gran part de la seva història, i actualment són una part perifèrica de dos diferents Estats: França i Itàlia. En ambdues illes han sigut presents, i encara ho són, moviments nacionalistes, tant illencs com continentals, una situació que ha generat una ulterior clivella. Aquesta tesi pretén analitzar, des d'una perspectiva comparada, els darrers tres segles d'història de Còrsega i Sardenya. El treball està dividit en dues parts, una primera dedicada a les dues illes, i una segona a un estudi de cas sobre un indret en particular d'aquest arxipèlag: l'Alguer. / Corsica and Sardinia, two islands that are hardly separated by 12 km, forms an archipelago in the middle of the western basin of the Mediterranean sea. However, they were divided along much of its history, and now they are a peripheral part of two different States: France and Italy. In both of these islands have been presents, and still are, nationalist movements, as islanders and continentals, a situation that has generated a further gap. This thesis aims to analyze, from a comparative point of view, the last three centuries of history of Corsica and Sardinia. The work is divided into two parts, the first devoted to the two islands, and the second one is a case study about particular place in this archipelago: Alghero.
80

Cambio y continuidad : la hacienda pública como factor de construcción estatal, Costa Rica 1812-1859

Rodríguez Solano, Pablo Augusto 21 November 2013 (has links)
El estado en Costa Rica a partir de 1812 fue posible por la constitución de una comunidad política. Ésta logró superar los conflictos coyunturales entre sus dirigentes mediante el balance de sus intereses económicos, en un gobierno construido a partir de un pacto político propio. El contexto económico, geográfico y político regional le permitió mantener la estabilidad. Esto se tradujo en una administración capaz de hacer frente a las complicaciones que se le presentaban, facilitando la modificación del pacto provincial mediante la centralización de poder en el gobierno, que progresivamente comenzó a hablar en nombre del estado. Para comprender el desarrollo de esta relación se hace necesario analizar la evolución de la hacienda, la población y el territorio, con tal de comprender la transición que realizó Costa Rica de Provincia a República. Pues es en la comprensión de la dialéctica entre herencia colonial y nuevos principios político-hacendarios donde se encuentra explicación de la construcción del estado. / The state in Costa Rica was made possible by the creation of a political community. It managed to overcome short-term conflicts between their leaders through the balance of their economic interests, in a government built from their own political pact. The economic, political and regional stability allowed the government to keep the continuity. This resulted in an administration capable of dealing with the complications that were presented to it, by facilitating modifications of the provincial pact that resulted in the centralization of power. From this the result was that the government gradually began to speak on behalf of the state. To understand the development of this relationship is necessary to analyze the evolution of finance, population and territory. Doing this we can understand the transition that made Costa Rica from a Province to a Republic. For it is in understanding the dialectic between colonial heritage and new political and fiscal principles that we can explain the state building process.

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