Memory effects and geometrical considerations in open quantum systems

This thesis discusses memory effects in open quantum systems with an emphasis on the Breuer, Laine, Piilo (BLP) measure of non-Markovianity. It is shown how the calculation of the measure can be simplifed and how quantum information protocols can bene t from memory e ects. The superdense coding protocol is used as an example of this. The quantum Zeno effect will also be studied from the point of view of memory e ects. Finally the geometric ideas used in simplifying the calculation of the BLP measure are applied in studying the amount of resources needed for detecting bipartite quantum correlations. It is shown that to decide without prior information if an unknown quantum state is entangled or not, an informationally complete measurement is required. The first part of the thesis contains an introduction to the theoretical ideas such as quantum states, closed and open quantum systems and necessary mathematical tools. The theory is then applied in the second part of the thesis as the results obtained in the original publications I-VI are presented and discussed.

Multipartite entanglement in harmonic oscillators subjected to dissipative quantum dynamics

Una detallada descripción de la dinámica de bajas energías del entrelazamiento multipartito es proporcionada para sistemas armónicos en una gran variedad de escenarios disipativos. Sin hacer ninguna aproximación central, esta descripción yace principalmente sobre un conjunto razonable de hipótesis acerca del entorno e interacción entorno-sistema, ambas consistente con un análisis lineal de la dinámica disipativa. En la primera parte se deriva un criterio de inseparabilidad capaz de detectar el entrelazamiento k-partito de una extensa clase de estados gausianos y no-gausianos en sistemas de variable continua. Este criterio se emplea para monitorizar la dinámica transitiva del entrelazamiento, mostrando que los estados no-gausianos pueden ser tan robustos frente a los efectos disipativos como los gausianos. Especial atención se dedicada a la dinámica estacionaria del entrelazamiento entre tres osciladores interaccionando con el mismo entorno o diferentes entornos a distintas temperaturas. Este estudio contribuye a dilucidar el papel de las correlaciones cuánticas en el comportamiento de la corrientes energéticas.

Superconducting Transition-Edge Sensor Physics

Despite record-setting performance demonstrated by superconducting Transition Edge Sensors (TESs) and growing utilization of the technology, a theoretical model of the physics governing TES devices superconducting phase transition has proven elusive. Earlier attempts to describe TESs assumed them to be uniform superconductors. Sadleir et al. 2010 shows that TESs are weak links and that the superconducting order parameter strength has significant spatial variation. Measurements are presented of the temperature T and magnetic field B dependence of the critical current Ic measured over 7 orders of magnitude on square Mo/Au bilayers ranging in length from 8 to 290 microns. We find our measurements have a natural explanation in terms of a spatially varying order parameter that is enhanced in proximity to the higher transition temperature superconducting leads (the longitudinal proximity effect) and suppressed in proximity to the added normal metal structures (the lateral inverse proximity effect). These in-plane proximity effects and scaling relations are observed over unprecedentedly long lengths (in excess of 1000 times the mean free path) and explained in terms of a Ginzburg-Landau model. Our low temperature Ic(B) measurements are found to agree with a general derivation of a superconducting strip with an edge or geometric barrier to vortex entry and we also derive two conditions that lead to Ic rectification. At high temperatures the Ic(B) exhibits distinct Josephson effect behavior over long length scales and following functional dependences not previously reported. We also investigate how film stress changes the transition, explain some transition features in terms of a nonequilibrium superconductivity effect, and show that our measurements of the resistive transition are not consistent with a percolating resistor network model.

Critical magnetic elds in superconducting systems with semi-metallic bands

In this work, we study the Zeeman splitting effects in the parallel magnetic field versus temperature phase diagram of two-dimensional superconductors with one graphene-like band and the orbital effects of perpendicular magnetic fields in isotropic two-dimensional semi-metallic superconductors. We show that when parallel magnetic fields are applied to graphene and as the intraband interaction decreases to a critical value, the width of the metastability region present in the phase diagram decreases, vanishing completely at that critical value. In the case of two-band superconductors with one graphene-like band, a new critical interaction, associated primarily with the graphene-like band, is required in order for a second metastability region to be present in the phase diagram. For intermediate values of this interaction, a low-temperature first-order transition line bifurcates at an intermediate temperature into a first-order transition between superconducting phases and a second-order transition line between the normal and the superconducting states. In our study on the upper critical fields in generic semi-metallic superconductors, we find that the pair propagator decays faster than that of a superconductor with a metallic band. As result, the zero field band gap equation does not have solution for weak intraband interactions, meaning that there is a critical intraband interaction value in order for a superconducting phase to be present in semi-metallic superconductors. Finally, we show that the out-of-plane critical magnetic field versus temperature phase diagram displays a positive curvature, contrasting with the parabolic-like behaviour typical of metallic superconductors.

Formação inicial do educador de infância no domínio da expressão motora

MONTEIRO, Paula - Formação inicial do educador de infância no domínio da expressão motora. Porto : [ed. autor], 2004. 299 p. Dissertação apresentada às provas de Mestrado em Ciências do Desporto - especialidade em desporto para crianças e jovens. Faculdade de Ciências do desporto e de Educação Física da Universidade do Porto.

Stoichiometry dependence of the evolution of the irradiated-induced defect clusters in lanthanum-doped ceria

To study the stoichiometry dependence of irradiation e ects in fluorite-type mixed oxide nuclear fuel (UPuO2), ion implantation in La doped ceria was used. Cerium dioxide single crystals with 0 mol%, 5 mol% and 25 mol% La concentration were irradiated with 1 MeV Kr ions at 800 C. In-situ transmission electron microscope (TEM) was utilized to observe the the damage process and defects created by the ion beam irradiation. Dislocation loops were observed after irradiation and were determined to be on {111} planes, but not on {220} or {200} planes. Ab substantial difference in the average size of dislocation loops for 0 %, 5% and 25% cases was observed at several doses.The growth rate of dislocation loops and the oxygen vacancy di usivity were found to be inversely correlated.

University Reforms in the Context of the Bologna Process

Georgia, a former Soviet Union state, has undergone a lot of political, social, economic and of course educational changes. This article shows how Georgia’s higher education system has developed after the collapse of the Soviet Union. As an independent country, Georgia has started developing a free nation with a new type of the education system. The government of Georgia chose the European system of higher education and their major aim was to become a part of the Bologna process. Reforms made in Georgian higher education system have been essential for the country and indeed a lot has changed since the starting period. Georgia managed to hold unified national entry exams and has implemented the ECTS system; there are modern curricula that meet the requirements of European standards. etc. But still, even though a lot is being done, a lack of funding, outdated teaching methods and old facilities in some universities are still unresolved problems.

El impacto de la capacitación a profesores fiscales de inglés de Cuenca

Se conoce que las convicciones de los profesores son el motor de su práctica docente (Borg, 2011); sin embargo, poco se sabe sobre cómo el desarrollo profesional influencia las convicciones de la enseñanza-aprendizaje y, por ende, las prácticas docentes. Escasa investigación se ha realizado sobre la influencia de la capacitación a profesores de inglés. Este estudio tiene el propósito de determinar el impacto de la capacitación en el empleo de estrategias comunicativas en el aula. Doce profesores fiscales de educación media que fueron capacitados en estrategias comunicativas en un curso1 de 110 horas presenciales y 20 horas de trabajo extra, son los sujetos de esta investigación. Se empleó una investigación cuasi-experimental de carácter prospectivo longitudinal, pues se utilizó una pre-observación, realizada antes de la intervención; una pos-observación, llevada a cabo luego de la finalización de la capacitación y una re-observación después de dos años de esta culminación. Los resultados indican cambios significativos en el pos-observación los que no se mantienen en la re-observación. Se recomienda implementar programas de desarrollo profesional continuo.

Beyond the Cosmological Principle

Simplifying the Einstein field equation by assuming the cosmological principle yields a set of differential equations which governs the dynamics of the universe as described in the cosmological standard model. The cosmological principle assumes the space appears the same everywhere and in every direction and moreover, the principle has earned its position as a fundamental assumption in cosmology by being compatible with the observations of the 20th century. It was not until the current century when observations in cosmological scales showed significant deviation from isotropy and homogeneity implying the violation of the principle. Among these observations are the inconsistency between local and non-local Hubble parameter evaluations, baryon acoustic features of the Lyman-α forest and the anomalies of the cosmic microwave background radiation. As a consequence, cosmological models beyond the cosmological principle have been studied vastly; after all, the principle is a hypothesis and as such should frequently be tested as any other assumption in physics. In this thesis, the effects of inhomogeneity and anisotropy, arising as a consequence of discarding the cosmological principle, is investigated. The geometry and matter content of the universe becomes more cumbersome and the resulting effects on the Einstein field equation is introduced. The cosmological standard model and its issues, both fundamental and observational are presented. Particular interest is given to the local Hubble parameter, supernova explosion, baryon acoustic oscillation, and cosmic microwave background observations and the cosmological constant problems. Explored and proposed resolutions emerging by violating the cosmological principle are reviewed. This thesis is concluded by a summary and outlook of the included research papers.

Brevíssima introdução a modelos matemáticos das pescas

Este texto foi elaborado para apoio a um módulo de 2 ECTS sobre "Métodos Quantitativos em Gestão das Pescas'' na unidade curricular 22195 - Seminário do curso de pós-graduação em "Gestão Sustentável de Recursos Marinhos: Pescas, Aquacultura e Consumo", da Universidade Aberta. O texto pretende constituir uma breve introdução à aplicação da Análise Matemática à modelação e gestão das pescas e não assume qualquer conhecimento prévio sobre o assunto, requerendo apenas conhecimentos de matemática que não são superiores aos obtidos a nível de uma licenciatura em Ciências Biológicas, Económicas, ou afins. Para que os leitores mais interessados nas aplicações, ou menos preparados matematicamente, não sejam desencorajados pelas partes matemáticas mais sofisticadas optou-se por colocá-las em anexos matemáticos no final do texto, deste modo possibilitando também aos leitores mais interessados irem ao fundo das questões e perceberem a razão da validade de determinados resultados.

Nutrient content in aboveground biomass of Brazilian peanut cultivars in conservation tillage on sugarcane straw and pasture area.

Fields studies were conducted in 2004/2005 in order to evaluate the effects of tillage on nutrient content in aboveground biomass of two peanut cultivars, cultivated in rotation after mechanical harvested sugarcane and pastures. These trials were carried out in two types of soils; Oxisol and Ultisol, respectively in Ribeir?ao Preto and Mirassol, S?ao Paulo State, Brazil. The experimental design was split-plot with four replications. Tillage treatments (conventional, minimum and no-tillage) were main plots while sub-plots were peanut genotypes IAC-Tatu ST (Valencia market-type, erect growth habit, red seed coat, maturity range around 100 days after planting) and IAC-Caiap´o (Runner market-type, prostate growth habit, pink testa, maturity range more than 135 days). From 15 to 90 days after emergence, samples of leaves and stems were harvested, dried, weighted and ground to determine macro and micronutrient concentration. At 75 days after sowing, the cultivar IAC-Caiap´o showed higher contents of N, P, K, Cu, and Zn while IAC-Tatu presented higher concentrations of Ca, Mg, and S. Zn content was higher in conservation tillage than in conventional, mainly in Oxisoil for both of cultivars.

La evaluación del primer curso del Grado en Turismo según la opinión del alumnado

El proyecto tiene como objetivo realizar el seguimiento del primer curso del Grado en Turismo a partir de la implementación de las guías docentes, investigación que se inició en el curso académico 2010-2011, coincidiendo con la implantación de dicha titulación en la Universidad de Alicante. En particular, el presente estudio aborda, a partir de un sistema de encuestas, el análisis de la opinión del alumnado matriculado en el curso 2013-2014, con el propósito de completar la serie de datos relativa a los cursos anteriores. De este modo, se efectúa el correspondiente estudio estadístico y con los resultados obtenidos se elabora un diagnóstico representativo de la trayectoria seguida hasta el momento, cuando se completa el primer ciclo de los estudios del Grado en Turismo y está más cerca la acreditación de la titulación. Por supuesto, como desde que se inició esta investigación, el fin último es mejorar en todo lo posible las guías docentes en cuanto instrumentos eficaces que puedan asegurar el óptimo rendimiento académico de los estudiantes.

Manual Breve de Derecho Eclesiástico del Estado (5ª edición)

Síntesis en 11 capítulos de los elementos más relevantes del Derecho eclesiástico español. Base para la docencia de la asignatura "Derecho eclesiástico del Estado" con una carga de 6 ECTS

Manual Breve de Libertades Públicas (3ª edición)

Exposición en 12 capítulos del algunos elementos de las libertades públicas y derechos fundamentales en el ordenamiento jurídico español. Manual básico de la asignatura "Libertades Públicas" en el Grado en Derecho, Mención Derecho Francés (6 créditos ECTS)

El efecto de la definición regulatoria de banda ancha sobre la difusión y la competencia del mercado de servicios de Internet fijo en Colombia

A partir de la dinámica evolutiva de la economía de las Tecnologías de la Información y las Comunicaciones y el establecimiento de estándares mínimos de velocidad en distintos contextos regulatorios a nivel mundial, en particular en Colombia, en el presente artículo se presentan diversas aproximaciones empíricas para evaluar los efectos reales que conlleva el establecimiento de definiciones de servicios de banda ancha en el mercado de Internet fijo. Con base en los datos disponibles para Colombia sobre los planes de servicios de Internet fijo ofrecidos durante el periodo 2006-2012, se estima para los segmentos residencial y corporativo el proceso de difusión logístico modificado y el modelo de interacción estratégica para identificar los impactos generados sobre la masificación del servicio a nivel municipal y sobre las decisiones estratégicas que adoptan los operadores, respectivamente. Respecto a los resultados, se encuentra, por una parte, que las dos medidas regulatorias establecidas en Colombia en 2008 y 2010 presentan efectos significativos y positivos sobre el desplazamiento y el crecimiento de los procesos de difusión a nivel municipal. Por otra parte, se observa sustituibilidad estratégica en las decisiones de oferta de velocidad de descarga por parte de los operadores corporativos mientras que, a partir del análisis de distanciamiento de la velocidad ofrecida respecto al estándar mínimo de banda ancha, se demuestra que los proveedores de servicios residenciales tienden a agrupar sus decisiones de velocidad alrededor de los niveles establecidos por regulación.