On dividends and other quantities of interest in the dual risk model

Doutoramento em Matemática Aplicada à Economia e à GestãoNesta dissertação trabalhamos em teoria do risco. Damos principal ênfase principal nos modelos de risco e teoria de ruína, dedicando a nossa atenção a algumas das mais interessantes e relevantes quantidades da área: a probabilidade da ruína, a transformada de Laplace e os dividendos descontados esperados. Os modelos de risco têm o objetivo de resolver, ou pelo menos, fornecer uma solução aproximada, a problemas que aparecem na prática do negócio dos seguros. Os desenvolvimentos que produzimos nesta dissertação têm a mesma finalidade. A nossa intenção é apresentar novas ferramentas para o cálculo das quantidades mencionadas acima, e uma melhor compreensão delas na prática. Consideramos o modelo dual de risco quando os tempos entre ganhos seguem uma distribuição exponencial matricial e, quando for possível, dar exemplos dos nossos resultados para casos particulares, como as distribuições Phase–Type e Erlang. Mostramos, na maioria dos casos, fórmulas e fazemos uso de técnicas matemáticas de várias áreas, como a teoria da probabilidade, a teoria das equações integro–diferenciais, a ágebra linear, análise complexa, entre outras.In this manuscript we work on risk theory. The main emphasis is on risk models and ruin theory, devoting our attention to some of the most interesting and relevant quantities in this area: ruin probabilities, Laplace transforms and expected discounted dividends. Risk models are meant to solve or, at least, provide an approximate solution, to problems that appear in the practice of the insurance business. The developments we produce in this dissertation have the same goal. Our aim is to present new tools for computation of the quantities mentioned above, and a better understanding of them in the practice. We consider the dual risk model when the interclaim times follow a matrix exponential distribution and, whenever possible, we give examples of our findings for particular cases, like the Phase–Type, the Generalized Erlang and the Erlang distributions. We show, in most cases, explicit formulas and we make use of mathematical techniques from several areas, like probability theory, the theory of integro–differential equations, linear algebra, complex analysis, among others.info:eu-repo/semantics/publishedVersio

Reflexiones sobre la evaluación de los sistemas de recuperación de información: necesidad, utilidad y viabilidad

The evaluation of Information Retrieval Systems has been developed parallelly to their evolution for reasons of scientific nature, generating the appearance of a great number of proposals to make this process. Assuming that all these proposals - most of which they appear in this work- try to look for a robust mechanism to measure the effectiveness of Information Retrieval Systems, it is not less certain information retrieval is a complex problem to resolve, due to the inherent problems related with translating the user’s information needs to a formalized expression search. The implementation of an objective and simple method to evaluate the effectiveness is the axis where the scene of the evaluation of the information retrieval gravitates

TABAQUISMO EN LA COMUNIDAD ESCOLAR.

The aim of this research is to try to know where our teenagers start taking nicotine, and if they start smoking in the adolescence, due to this habit belongs to our society one hundred years ago. The experience shows us that the eighty percent of the teenagers younger than 20 take it or they are addicted to smoking before this age. We have tried to research about the teenagers thinkings making some questions from a Mercedes Milá magazine, published in 2005. This magazine tries to show the reality of the life with tobacco. The video has been showed at the following schools: Salvador Ruso, Virgen del Carmen, Nº 8, Las Culturas, Institutos Mare Nostrum and La Purísima, with 1140 pupils from eleven to sixteen years old. The purpose was to give them some tools to give up smoking. So that, we want to show to collective nurse how important is the teaching at schools, within the usual activity of their jobs, avoiding to forget this activity, which was carried on with much effort by our predecessors.La finalidad que se pretende con este trabajo de investigación realizado es intentar averiguar dónde nuestros adolescentes se introducen como consumidores en el mundo de la nicotina, intentar averiguar si el adolescente tiene impuesto por tradición, ya que es parte de la vida cotidiana y social de nuestra civilización en los últimos 100 años, empezar a fumar en la adolescencia, pues la evidencia nos dice que el 80% de los adolescentes menores de 20 años lo prueban o quedan enganchados antes de esa edad. Hemos intentado indagar un poco en los pensamientos de los adolescentes con una serie de preguntas sacadas de un programa de Mercedes Milá, editado en 2005, donde se intenta ver la realidad de la vida con el tabaco. El video se ha proyectado en los colegios Salvador Ruso, Virgen del Carmen, nº8, Las Culturas, e Institutos Mare Nostrum, Nº y La Purísima con un volumen de 1140 alumnos y con edades comprendidas entre 11 y 16 años con el único fin de intentar poner medios o dar salida a aquellos alumnos que lo demanden. Para ello se hace llegar a toda el colectivo enfermero la importancia de la DOCENCIA en los colegios, dentro de una practica habitual de su trabajo, no dejando que esta actividad que tanto costó llevar a la práctica por nuestros predecesores se pierda sin dar importancia al buen fin que para ello se creó

Broadening the Chemical Scope of Laccases: Selective Deprotection of N-Benzyl Groups

El sistema catalítico formado por la lacasa de Trametes versicolor y el TEMPO es utilizado de forma eficiente para llevar a cabo la desprotección quimioselectiva de los grupos N-bencilo primarios en condiciones suaves de reacción.Laccase from Trametes versicolor together with TEMPO has been found as a very efficient system to deprotect Nbenzylated primary amines, differing from previously described methods since it uses oxygen as mild oxidant in aqueous medium. Chemoselective removal of the benzyl group was achieved with excellent yields when secondary amine and alcohol moieties were also presentMICINN (Projects CTQ2011-24237 and CTQ2013-44153). Principado de Asturias (predoctoral fellowship Severo Ochoa)

Effect of posterior gingival smile on the perception of smile esthetics

Objectives: To evaluate and compare the influence of posterior gummy smile on the perception of smile esthetics by orthodontists, general-dentists and laypersons. Study Design: A frontal photograph of a smile with normal gum exposure was chosen and manipulated digitally using Adobe Photoshop C3 to generate three further images with posterior gum exposure of 4, 6 and 8mm. These four images were assessed by the three evaluator groups: orthodontists (n=40), general-dentists (n=40) and laypersons (n=40). Both orthodontists and dentists had at least ten years professional experience and laypersons were aged between 40-50 years. The proportion of men to women was 20:20 in each group. Evaluators awarded a score to the smile esthetics of each image: 1=acceptable, 2=moderately acceptable, 3=unacceptable. Afterwards, each evaluator placed the four images in order of esthetic preference. Results: No significant differences (p>0.05) were detected between the three evaluator groups for the photo without posterior gummy smile. The perception of smile esthetics for a the 4mm posterior gummy smile (median for orthodontists=2, general-dentists= 1, laypersons=1), the 6mm (median for orthodontists=2, general-dentists=1, laypersons=1) and the 8mm (median for orthodontists=3, general-dentists=2, laypersons=2) was significantly different between orthodontists and the other two evaluator groups (p<0.0017). The three evaluator groups coincided in placing the image with the 6mm gum exposure in first place in order of esthetic preference. Conclusions: Posterior gummy smile influences the perception of smile esthetics more negatively among orthodontists than the rest of the groups

Measures to evaluate quality of care in renal cancer: results of a Delphi study in Spain.

Purpose: To review current measures for renal cancer care and develop a comprehensive and updated list of measures for their practical use. Methods: The study was developed by Fundación ECO, a Spanish foundation aiming to improve oncology quality of care. A systematic literature review was carried out to identify measures and knowledge gaps. A scientific committee composed of 9 experts reviewed the literature findings and added measures. A preliminary list of 42 measures was evaluated with the Delphi method to gather feedback from 47 medical oncology experts in Spain. Experts scored the appropriateness of the measures and ranked their priority in 2 consecutive online surveys. The scientific committee reviewed the Delphi results and developed the measures. A technical group from Universidad Francisco de Vitoria conducted and oversaw the Delphi method. Results: The Delphi method led to consensus on all 42 measures. The scientific committee used a prioritisation matrix to select 25 of these measures for evaluating quality of care in renal cancer. These measures regarded structure, process, and outcome and covered general management, diagnosis, treatment, follow-up, and evaluation of health outcomes. Easy-to-use index cards were developed for all 25 measures, including their definition, formula, acceptable level of attainment, and rationale. Conclusions: This manuscript aims to provide healthcare professionals with expert- and evidence-based measures that are useful for evaluating quality of care in renal cancer and cover all aspects and stages.pre-print451 K

Lactonization reactions through hydrolase-catalyzed peracid formation. Use of lipases for chemoenzymatic Baeyer-Villiger oxidations of cyclobutanones.

Lactonization reactions through hydrolase-catalyzed peracid formation. Use of lipases for chemoenzymatic Baeyer–Villiger oxidations of cyclobutanones.A one-pot chemoenzymatic method has been described for the synthesis of gamma-butyrolactones starting from the corresponding ketones through a Baeyer–Villiger reaction. The approach is based on a lipase-catalyzed perhydrolysis for the formation of peracetic acid, which is the responsible for the ketone oxidation. Optimization studies have been performed in the oxidation of cyclobutanone, finding Candida antarctica lipase type B, ethyl acetate and urea-hydrogen peroxide complex as the best system. The relative ratio of these reagents has also been analyzed in depth. This synthetic approach has been successfully extended to a family of 3-substituted cyclobutanones in high substrate concentration, yielding the corresponding lactones with excellent isolated yields and purities, under mild reaction conditions and after a simple extraction protocol.Ministerio de Ciencia e Innovación (MICINN-12-CTQ2011-24237 y CTQ-2013-44153-P) Principado de Asturias (SV-PA-13-ECOEMP-42) Universidad de Oviedo (UNOV-13-EMERG-01

Complicaciones en el uso de aloinjertos intercalares tras resección de tumores óseos

La reconstrucción ósea mediante aloinjertos intercalares es una técnica de uso frecuente tras resecciones tumorales, que presenta -a largo plazo- mejores resultados que las endoprótesis diafisarias o los autoinjertos vascularizados. Sin embargo, entre las complicaciones más frecuentes destacan las infecciones y las fracturas del aloinjero asociadas a roturas o aflojamientos de la osteosíntesis. Se presentan dos casos tratados con reconstrucciones de este tipo en los que el sistema de osteosíntesis utilizado fracasó, en uno de ellos de forma repetida.The reconstruction of skeletal defects using bone allografts is a frequent procedure after tumoral resections associated to good long-term results, usually better than diaphyseal endoprostheses or autologous grafts. Nevertheless, there are some complications: infection and allograft fracture associated with failure or broken fixation. We report two cases of bone reconstruction in who the fixation failed, twice in one of them

Composing Model Transformations at Runtime: an approach for adapting Component-based User Interfaces

Nowadays, large part of the efforts in software development are focused on achieving systems with an as high as possible level of adaptation. With the traditional technique of model-driven development this can be largely accomplished. The inconvenience of these techniques however, is that the models are usually manipulated at design-time by means of fixed transformation. Furthermore, the transformations that manipulate these models cannot change dynamically according to the current execution context. This paper presents a transformation pattern aimed to adapt architectural models at runtime, this means that these models may change dynamically at runtime. The transformations that produce this model adaptation are not fixed, but dynamically composed by selecting the most appropriate set of rules from those available in a repository. As an example scenario for the application of these transformations, we chose architectural models representing component-based UIs