955 resultados para Prospective analysis


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Study Objective: To evaluate the diagnostic accuracy of transvaginal ultrasound and office hysteroscopy in the differentiation between endometrial polyps and endometrial adenocarcinoma. Design: This is a prospective 100 women longitudinal study, 24 to 80 years, submitted to hysteroscopic polypectomy (n = 80) or surgery due to endometrial adenocarcinoma (n = 20), from january 2010 to December 2011. Clinical, ultrasonographic and hysteroscopic parameters were analyzed and compared with histopathologic find. Statistical analysis were performed utilizing the Tukey, Kruskal-Wallis, Dunn and Mann-Whitney test, with a confidence interval of 95% and p\0, 05 statiscally significant. Setting: Botucatu Medical School. Intervention: Prospective analysis of clinical, ultrasonographic and hysteroscopic parameters in patients with diagnosis suspected of endometrial polyps and adenocarcinoma of endometrium were performed. According to the diagnosis, hysteroscopic polypectomy or pan hysterectomy with lymph node sampling was realized. After the surgery and histopathological study, statistical analysis of parameters was performed and the results were compared between groups. It was Research Ethics Committee approved. Measurements and Main Results: There were no differences between age, BMI, menopause, TH use and associated diseases among groups. The main symptom of endometrial cancer was the postmenopausal bleeding, affecting 84,2% of women against 34,8% of polypectomy group. The majority of women with endometrial polyps were asymptomatic. Transvaginal ultrasonography showed no ability to differentiate cases of endometrial cancer compared with the cases of endometrial polyps, considering the presence of endometrial thickness and blood flow on color Doppler. Office hysteroscopy showed significant changes in 75% of the adenocarcinoma cases, especially the presence of diffuse hypervascularity with atypical vessels. Conclusion: Still remains an inability to establish clinical parameters and reliable ultrasound imaging to differentiate endometrial polyps and cancer of endometrium. Attention should be given to hysteroscopic exams presenting diffuse endometrial hypervascularization with architectural distortion of the vessels. The recommendation of our service remains the systematic removal of all endometrial polyps.

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The retaking of the ethanol program in the year 2003 as a fuel for light road transportation in Brazil through the introduction of flex fuel vehicles fleet was a good strategy to overcome the difficulties of the ethanol production sector and did work to increase its market share relative to gasoline. This process, however, may cause a future disequilibrium on the food production and on the refining oil derivates structure. In order to analyze the substitution process resultant of the competition between two opponents fighting for the same market, in this case the gasoline/ethanol substitution process, a method derived from the biomathematics based on the non-linear differential equations (NLDE) system is utilized. A brief description of the method is presented. Numerical adherence of the method to explain several substitution phenomena that occurred in the past is presented in the previous author`s paper, in which the urban gas pipeline system substitution of bottled LPG in the dwelling sector and the substitution of the urban diesel transportation fleet by compressed natural gas (CNG) buses is presented. The proposed method is particularly suitable for prospective analysis and scenarios assessment. (c) 2008 Elsevier Ltd. All rights reserved.

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Objective: To evaluate the clinical outcomes of multivisceral transplantation (MVT) in the setting of diffuse thrombosis of the portomesenteric venous system. Background: Liver transplantation (LT) in the face of cirrhosis and diffuse portomesenteric thrombosis (PMT) is controversial and contraindicated in many transplant centers. LT using alternative techniques such as portocaval hemitransposition fails to eliminate complications of portal hypertension. MVT replaces the liver and the thrombosed portomesenteric system. Methods: A database of intestinal transplant patients was maintained with prospective analysis of outcomes. The diagnosis of diffuse PMT was established with dual-phase abdominal computed tomography or magnetic resonance imaging with venous reconstruction. Results: Twenty-five patients with grade IV PMT received 25 MVT. Eleven patients underwent simultaneous cadaveric kidney transplantation. Biopsy-proven acute cellular rejection was noted in 5 recipients, which was treated successfully. With a median follow-up of 2.8 years, patient and graft survival were 80%, 72%, and 72% at 1, 3, and 5 years, respectively. To date, all survivors have good graft function without any signs of residual/recurrent features of portal hypertension. Conclusions: MVT can be considered as an option for the treatment of patients with diffuse PMT. MVT is the only procedure that completely reverses portal hypertension and addresses the primary disease while achieving superior survival results in comparison to the alternative options.

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Purpose : To angiographically evaluate infrapopliteal arterial lesion morphology in a consecutive series of patients presenting with critical limb ischemia (CLI) and undergoing infrapopliteal angioplasty. Methods : A prospective analysis was undertaken of a consecutive series of CLI patients undergoing endovascular therapy in a tertiary referral center in the year 2011. Morphological assessment of baseline angiograms obtained prior to revascularization included lesion length, assessment of calcification using a semi-quantitative scoring system, and reference vessel diameter (RVD) measurement. Delta RVDs were assessed subtracting distal RVDs from proximal RVDs. A total of 197 infrapopliteal lesions in 105 CLI patients (n=106 limbs) were assessed. Of these, 136 lesions were treated by endovascular means. Results : The average length of treated lesions was 87.1±43.8 mm in stenoses and 124.0±78.3 mm in chronic occlusions (p<0.001). Mean RVD proximal to the lesions was 1.88 mm whereas it was 1.66 mm distal to the lesions (p≤0.03). Mean arterial calcification was 1.15. Conclusion : This prospective angiographic series underlines the complex nature and extensive longitudinal involvement of infrapopliteal lesions in CLI patients. These findings should be taken into consideration for anti-restenosis concepts in this challenging subgroup of peripheral artery disease patients.

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INTRODUCTION: Maintaining arterial blood glucose within tight limits is beneficial in critically ill patients. Upper and lower limits of detrimental blood glucose levels must be determined. METHODS: In 69 patients with severe traumatic brain injury (TBI), cerebral metabolism was monitored by assessing changes in arterial and jugular venous blood at normocarbia (partial arterial pressure of carbon dioxide (paCO2) 4.4 to 5.6 kPa), normoxia (partial arterial pressure of oxygen (paO2) 9 to 20 kPa), stable haematocrit (27 to 36%), brain temperature 35 to 38 degrees C, and cerebral perfusion pressure (CPP) 70 to 90 mmHg. This resulted in a total of 43,896 values for glucose uptake, lactate release, oxygen extraction ratio (OER), carbon dioxide (CO2) and bicarbonate (HCO3) production, jugular venous oxygen saturation (SjvO2), oxygen-glucose index (OGI), lactate-glucose index (LGI) and lactate-oxygen index (LOI). Arterial blood glucose concentration-dependent influence was determined retrospectively by assessing changes in these parameters within pre-defined blood glucose clusters, ranging from less than 4 to more than 9 mmol/l. RESULTS: Arterial blood glucose significantly influenced signs of cerebral metabolism reflected by increased cerebral glucose uptake, decreased cerebral lactate production, reduced oxygen consumption, negative LGI and decreased cerebral CO2/HCO3 production at arterial blood glucose levels above 6 to 7 mmol/l compared with lower arterial blood glucose concentrations. At blood glucose levels more than 8 mmol/l signs of increased anaerobic glycolysis (OGI less than 6) supervened. CONCLUSIONS: Maintaining arterial blood glucose levels between 6 and 8 mmol/l appears superior compared with lower and higher blood glucose concentrations in terms of stabilised cerebral metabolism. It appears that arterial blood glucose values below 6 and above 8 mmol/l should be avoided. Prospective analysis is required to determine the optimal arterial blood glucose target in patients suffering from severe TBI.

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OBJECTIVE: The few long-term follow-up data for sentinel lymph node (SLN) negative breast cancer patients demonstrate a 5-year disease-free survival of 96-98%. It remains to be elucidated whether the more accurate SLN staging defines a more selective node negative patient group and whether this is associated with better overall and disease-free survival compared with level I ; II axillary lymph node dissection (ALND). METHODS: Three-hundred and fifty-five consecutive node negative patients with early stage breast cancer (pT1 and pT2< or =3 cm, pN0/pN(SN)0) were assessed from our prospective database. Patients underwent either ALND (n=178) in 1990-1997 or SLN biopsy (n=177) in 1998-2004. All SLN were examined by step sectioning, stained with H;E and immunohistochemistry. Lymph nodes from ALND specimens were examined by standard H;E only. Neither immunohistochemistry nor step sections were performed in the analysis of ALND specimen. RESULTS: The median follow-up was 49 months in the SLN and 133 months in the ALND group. Patients in the SLN group had a significantly better disease-free (p=0.008) and overall survival (p=0.034). After adjusting for other prognostic factors in Cox proportional hazard regression analysis, SLN procedure was an independent predictor for improved disease-free (HR: 0.28, 95% CI: 0.10-0.73, p=0.009) and overall survival (HR: 0.34, 95% CI: 0.14-0.84, p=0.019). CONCLUSIONS: This is the first prospective analysis providing evidence that early stage breast cancer patients with a negative SLN have an improved disease-free and overall survival compared with node negative ALND patients. This is most likely due to a more accurate axillary staging in the SLN group.

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We investigated cross-sectional associations between intakes of zinc, magnesium, heme- and non heme iron, beta-carotene, vitamin C and vitamin E and inflammation and subclinical atherosclerosis in the Multi-Ethnic Study of Atherosclerosis (MESA). We also investigated prospective associations between those micronutrients and incident MetS, T2D and CVD. Participants between 45-84 years of age at baseline were followed between 2000 and 2007. Dietary intake was assessed at baseline using a 120-item food frequency questionnaire. Multivariable linear regression and Cox proportional hazard regression models were used to evaluate associations of interest. Dietary intakes of non-heme iron and Mg were inversely associated with tHcy concentrations (geometric means across quintiles: 9.11, 8.86, 8.74, 8.71, and 8.50 µmol/L for non-heme iron, and 9.20, 9.00, 8.65, 8.76, and 8.33 µmol/L for Mg; ptrends <0.001). Mg intake was inversely associated with high CC-IMT; odds ratio (95% CI) for extreme quintiles 0.76 (0.58, 1.01), ptrend: 0.002. Dietary Zn and heme-iron were positively associated with CRP (geometric means: 1.73, 1.75, 1.78, 1.88, and 1.96 mg/L for Zn and 1.72, 1.76, 1.83, 1.86, and 1.94 mg/L for heme-iron). In the prospective analysis, dietary vitamin E intake was inversely associated with incident MetS and with incident CVD (HR [CI] for extreme quintiles - MetS: 0.78 [0.62-0.97] ptrend=0.01; CVD: 0.69 [0.46-1.03]; ptrend =0.04). Intake of heme-iron from red meat and Zn from red meat, but not from other sources, were each positively associated with risk of CVD (HR [CI] - heme-iron from red meat: 1.65 [1.10-2.47] ptrend = 0.01; Zn from red meat: 1.51 [1.02 - 2.24] ptrend =0.01) and MetS (HR [CI] - heme-iron from red meat: 1.25 [0.99-1.56] ptrend =0.03; Zn from red meat: 1.29 [1.03-1.61]; ptrend = 0.04). All associations evaluated were similar across different strata of gender, race-ethnicity and alcohol intake. Most of the micronutrients investigated were not associated with the outcomes of interest in this multi-ethnic cohort. These observations do not provide consistent support for the hypothesized association of individual nutrients with inflammatory markers, MetS, T2D, or CVD. However, nutrients consumed in red meat, or consumption of red meat as a whole, may increase risk of MetS and CVD.^

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Smoking is often initiated in adolescence through trying or experimenting with cigarettes. Smoking initiation is the beginning critical stage in the smoking trajectory often resulting in addiction. This dissertation examined the effect of parenting variables on smoking initiation behavior among 11–14 year old Mexican origin adolescents, a largely understudied group. The participants in this study were part of a population-based cohort of Mexican origin adolescents residing in Houston, Texas. ^ Aim 1 of this study assessed the appropriateness of the Family Life Questionnaire (FLQ) among Mexican origin adolescents. Second order confirmatory factor analysis (CFA) was performed to examine the factor structure of the FLQ and measurement invariance testing was conducted to evaluate the cross-cultural validity of this scale. Aim 2 analyzed cross-sectional associations between parenting variables and adolescent ever tried smoking behavior while aim 3 focused on prospective examination of changes in parenting variables from baseline to final follow-up on ever tried smoking behavior among never smokers. ^ Overall, the results of the CFA indicated that the original factor structure of the FLQ, with alterations, was a good fit for the Mexican origin adolescents. The measurement invariance analysis of the modified FLQ scale indicated adequate measurement invariance. The aim 2 cross-sectional analyses indicated that family cohesion was significantly associated with lower odds of ever tried smoking. Authoritarian parenting was significantly associated with smoking initiation only at the baseline while family conflict was significantly associated with smoking initiation only at the two-year final home visit. The findings from the aim 3 prospective analysis indicated that changes in levels of family cohesion and conflict are important predictors of smoking initiation among those who have never tried smoking. Specifically, perceiving low levels of family cohesion and a decrease in the family cohesion over two years, as well as perceiving high levels of family conflict and an increase in conflict over two years was associated with smoking initiation among never smokers. ^ In general, the findings of this study provide important insights on the links between parenting and adolescent smoking and assist in designing prevention and intervention programs that emphasize the role of family bonding to prevent adolescent smoking behavior. Family education programs for Mexican culture could also highlight the positive effects of authoritarian practices and good family communication to prevent family conflict and subsequent smoking behavior.^

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Ante la cuestión ¿La universidad debe amoldarse a la realidad ambiental o debe precursar nuevas realidades? se propone demostrar la factibilidad de alcanzar aproximaciones objetivables hacia el desarrollo sostenible, mediante la cooperación universitaria transfronteriza en ambientes urbanos insulares y costeros de la subregión del Caribe y Centroamérica. Se desarrolla el estudio en cuatro momentos: momento proyectivo en el cual se delimita el problema y se contextualiza su significación en el plano teórico de las sub-áreas implicadas. Fue reconocida la existencia de un problema social que, más allá de significar una actuación negativa intencional humana, revela una insuficiencia en el aprovechamiento de un potencial conocido y estratégico cuyos síntomas suelen ser: crisis ambiental generalizada; poca capacidad de respuesta por parte de las universidades ante las exigencias del desarrollo sostenible; incipientes estrategias de cooperación interinstitucional con refuerzo negativo en la atomización de esfuerzos materiales y comunicacionales. Se contrastaron enfoques y se adoptó una postura ante un hecho determinante: La universidad como articulador del desarrollo sostenible; hecho concretado en un objeto investigable: la cooperación universitaria como estrategia aún no focalizada en acercamientos al desarrollo sostenible. En la estrategia de abordaje de la investigación, la gestión fue considerada hipótesis de trabajo no positivista, generando en consecuencia la aplicación de adaptaciones a metodologías reconocidas, contextualizadas dentro de una particular visión sobre del hecho investigado. En el momento metodológico se describe el diseño concreto y los procedimientos de abordaje del problema en todas sus fases. En el momento técnico, fueron aplicados instrumentos y técnicas para obtener los datos diagnósticos e iniciar el diseño de un modelo de cooperación universitaria para el desarrollo sostenible. El diagnóstico se basó en estrategias cuali-cuantitativas que permitieron el análisis de resultados en la aplicación de encuestas, entrevistas a expertos, análisis prospectivo estructural, situacional e integrado. La construcción del modelo se desarrolló con fundamento en experiencias de cooperación previas, adoptando modelos de gestión de relevante alcance científico como referencias de aplicación. Se trata de una investigación socio-ambiental cuyo objeto de estudio la identifica como no experimental, aplicada; basada en el análisis descriptivo de datos cualicuantitativos, conducidos en un diseño de campo devenido finalmente en un proyecto factible. La información se recolectada por observación de campo, aplicación de instrumentos y dinámicas inspiradas en grupos de enfoque a escala local y nacional; con sujetos pertenecientes al sistema de educación universitaria e instancias gubernamentales y sociales propias del ámbito seleccionado. Conduce el estudio a la presentación del modelo MOP-GECUDES, descrito en cuanto a sus dimensiones, variables, estrategias; con 166 indicadores clasificados en 49 categorías, expresados en metas. Se presenta en 24 procedimientos, apoyados en 47 instrumentos específicos consistentes en aplicaciones prácticas, hojas metodológicas o manual de instrucciones para la operacionalización del modelo. Se complementa el diseño con un sistema de procedimientos surgidos de la propia experiencia, lo que le atribuye el modelo diseñado el rasgo particular de haber sido diseñado bajo sus propios principios. Faced with the question: Does the college must conform to the environmental reality or has to should promote new realities? This research aims to demonstrate the feasibility of achieving objectifiable approaches towards sustainable development through cross-border university cooperation in urban, coastal and islands space" of Caribbean and Central American. This study is developed in four stages: projective moment, in which delimits the problem, and contextualizes its importance in their theoretical subareas. It was recognized that there is a social problem, that beyond an intentional human action negative, reveals a deficience ability in exploiting potential strategic known and whose symptoms are: widespread environmental crisis, poor ability to answer on the part of universities to the demands of sustainable development; emerging interagency cooperation strategies with the aggravating fragmentation of resources. Were contrasted Approaches and was been adopted a stance before a triggering event: The university as articulator of sustainable development. Fact materialized in a study object: university cooperation as a strategy that yet has not been focused on approaches to sustainable development. In research approach, the management was considered as a working-hypothesis not positivist, consequently, were applied adjustments recognized methodologies that were contextualized within the author's personal view on the matter under investigation. En el momento metodológico se describe el diseño concreto y los procedimientos de abordaje del problema en todas sus fases. At the methodological time, describes the design and procedures to address the problem in all its phases. At the technical time, were applied tools directed to obtain diagnostic data and start designing a model of university cooperation for sustainable development. The diagnosis was based on qualitative and quantitative strategies that allowed the analysis of findings in the surveys, expert interviews, prospective analysis, and structural situational and integrated. Construction of the model was developed on the basis of cooperation experiences of the author, adopting management models relevant scientific scope and application references. It is a socio-environmental research with a not-experimental focus of study, applied, based on the descriptive analysis of qualitative and quantitative data, conducted in a field design that finally was been become a feasible project. The information is collected by field observation, application of instruments inspired in dynamic focus groups at local and national levels, with individual-subjects of the university education system; the government bodies and the social groups of the selected area. The Study leads to the presentation of the model MOP-GECUDES, described in terms of their dimensions, variables, strategies; with 166 indicators classified in 49 categories, expressed in its activities and goals. It comes in 24 procedures, supported by 47 specific instruments consisting of practical applications, methodology sheets or instructions for the operationalization of the model. Design is complemented with a system of procedures arising from the own experience. This have the particular attribute of generate a model than has been designed under its own principles.

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En claro alineamiento con estrategias de sostenibilidad en el uso de recursos naturales en un escenario constante de aumento de la demanda energética mundial, el desarrollo de la tecnología energética en la Historia de la Especie Humana muestra un vector de evolución permanente desde su origen en el sentido del desarrollo y uso de nuevas fuentes energéticas con la explotación de recursos naturales de manera más eficiente: soluciones energéticas con aumento de la densidad energética (exoenergía de proceso por unidad de masa de recurso natural). Así el cambio de escala en la demanda de explotación del Litio como recurso natural se viene presentando en la última década ligada al desarrollo del mercado de las baterías "ion-Litio" y los requisitos de combustible (Deuterio y Litio) en el camino de la fusión nuclear como opción energética próxima. El análisis anticipado de las demandas sinérgicas a escala de ambos mercados aparece de enorme interés prospectivo en sus aspectos técnicos: (1) tecnologías de base para la extracción mineral y de agua marina y (2) su enriquecimiento isotópico (de interés sinérgico; 7Li para baterías eficientes ion-litio; 6Li como regenerador de tritio en ciclo de combustible en fusión nuclear) a la vez que en sus aspectos económicos. Este Proyecto realiza: (1) un ejercicio de análisis prospectivo de la demanda y de mercado para el enriquecimiento 6Li/7Li para las próximas décadas, (2) se califican los desarrollos tecnológicos específicos que van a poder permitir la producción a escala conforme a la demanda; (3) se selecciona y califica una técnica [de centrifugación / termo-difusión/ destilación combinada] como opción tecnológicamente viable para la producción a escala de formas litiadas; (4) se propone un diseño conceptual de planta de producción y finalmente (5) propone un estudio de viabilidad para la demostración de proceso y construcción de dicha planta de demostración de la nueva capacidad tecnológica. ABSTRACT Clearly aligned with sustainability strategies under growing world energy demand in the use of natural resources the development of energy technology in the history of the human species shows a vector of ongoing evolution from its origin in the sense of the development and use of new energy sources with the exploitation of natural resources in a more efficient manner. The change of scale in the demand for exploitation of Lithium as a natural resource appears during the last decade as bound to the deployment of "lithium-ion" batteries market and to the Nuclear Fusion fuels (deuterium and lithium) supply scaled demands. The prospective analysis of demands to scale in both markets appears in scene with huge prospective interest in its technical aspects: (1) base technologies for mineral and water marine extraction (2) its isotopic enrichment (synergistic interests; 7Li efficient battery Li-ion; 6Li as fusion nuclear fuel breeder (tritium) as well as in its economic aspects. This Project: (1) propose a prospective analysis exercise of the synergistic supply demand for coming decades for the enrichment of 6Li and 7Li, (2) qualifies specific technological developments ongoing to respond to supply demand; (3) select and qualifies an appropriate technique [combined centrifugation/thermo-diffusion/distillation] as technologically viable option for lithiated forms scaled-production; (4) proposes a conceptual design of production plant based on the technique and finally (5) proposes a feasibility study for the process demonstration and construction of this new technological capability Demonstration Plant.

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El estándar LTE se ha posicionado como una de las claves para que los operadores de telecomunicación puedan abordar de manera eficiente en costes el crecimiento de la demanda de tráfico móvil que se prevé para los próximos años, al ser una tecnología más escalable en el núcleo de la red y más flexible en la interfaz radio que sus predecesoras. En este sentido, es necesario también que los reguladores garanticen un acceso al espectro radioeléctrico adecuado, equitativo y no discriminatorio, que permita un entorno estable para el despliegue de redes de comunicaciones móviles avanzadas. Además de la flexibilización del marco regulador del espectro radioeléctrico en Europa, que ha permitido el despliegue de nuevas tecnologías en las bandas de frecuencia históricas de GSM, se ha puesto a disposición espectro adicional para sistemas IMT en nuevas bandas de frecuencia, lo que ha planteando a su vez nuevos retos para la tecnología y la regulación. La fragmentación del espectro disponible para comunicaciones móviles ha impulsado el desarrollo de técnicas de agregación de portadoras en las nuevas versiones del estándar LTE, que permiten explotar mejor los recursos radio en su conjunto. No obstante, el espectro inferior a 1 GHz sigue siendo escaso, ya que el tráfico móvil aumenta y la banda de 900 MHz aún se utiliza para servicios GSM, lo que no ha conseguido sino agravar la disputa entre los servicios de radiodifusión terrestre y de comunicaciones móviles por la parte superior de la banda UHF. En concreto, la banda de 700 MHz se perfila como una de las próximas para aumentar el espectro disponible para los servicios en movilidad, si bien su liberación por parte de las actuales redes de Televisión Digital Terrestre presenta no pocas dificultades en los Estados miembros en los que ésta es la principal plataforma audiovisual de acceso gratuito, abriendo un debate sobre el modelo audiovisual a largo plazo en Europa. Por otro lado, las políticas públicas de promoción del acceso a la banda ancha rápida y ultrarrápida de la presente década han establecido objetivos ambiciosos para el año 2020, tanto en el ámbito europeo como en los diferentes Estados miembros. La universalización del acceso a redes de banda ancha de al menos 30 Mbps constituye uno de los principales retos. Las expectativas generadas por la tecnología LTE y la puesta a disposición de nuevas bandas de frecuencia hace posible que los servicios de acceso fijo inalámbrico adquieran especial relevancia ante los objetivos de política pública establecidos que, como ha sido reconocido en diversas ocasiones, no podrán lograrse sino con un compendio de diferente tecnologías. Para esta Tesis Doctoral se han desarrollado una serie modelos tecnoeconómicos con el objetivo de realizar un análisis prospectivo que evalúa tres casos de especial relevancia en el despliegue de redes LTE: en primer lugar, la valoración económica de la banda de 700 MHz; en segundo lugar, la evaluación de modelos de negocio y reducción de costes considerando tecnologías femtocelulares; y finalmente, la viabilidad de las redes LTE de acceso fijo inalámbrico para el cierre de la brecha digital en el acceso a la banda ancha de 30 Mbps. En relación con la aplicación del análisis tecnoeconómico para la valoración del espectro de 700 MHz, los resultados obtenidos ponen de manifiesto dos cuestiones fundamentales. En primer lugar, la necesidad de asignar a los operadores más espectro para satisfacer las previsiones de demanda de tráfico móvil a medio plazo. En segundo, existe una diferencia notable en los costes de despliegue de una red LTE cuando se dispone de espectro en frecuencias inferiores a 1 GHz y cuando no, pero esta diferencia de costes disminuye a medida que se añade nuevo espectro sub-1GHz. De esta manera, la atribución de la banda de 700 MHz a servicios de comunicaciones móviles supone una reducción relevante en los costes de despliegue si el operador no dispone de espectro en la banda de 800 MHz, pero no así si ya dispone de espectro en bandas bajas para el despliegue. En este sentido, puede concluirse que el precio que los operadores estarán dispuestos a pagar por el espectro de la banda de 700 MHz dependerá de si ya tienen disponible espectro en la banda de 800 MHz. Sin embargo, dado que la competencia por ese espectro será menor, los ingresos esperables en las licitaciones de esta nueva banda serán en general menores, a pesar de que para algunos operadores este espectro sería tan valioso como el de 800 MHz. En segundo lugar, en relación con el despliegue de femtoceldas pueden extraerse algunas conclusiones en términos de ahorro de costes de despliegue y también de cara a la viabilidad de los modelos de negocio que posibilitan. El ahorro que supone la introducción de femtoceldas en el despliegue de una red LTE frente al caso de un despliegue exclusivamente macrocelular se ha demostrado que es mayor cuanto menor es el ancho de banda disponible para la red macrocelular. En esta línea, para un operador convergente el despliegue de femtoceldas tiene sentido económico si el ancho de banda disponible es escaso (en torno a 2x10 MHz), que, en el caso de España, puede reflejar el caso de los operadores del segmento fijo que son nuevos entrantes en el móvil. Por otro lado, los modelos de acceso abierto son interesantes para operadores exclusivamente móviles, porque consiguen flexibilizar los costes sustituyendo estaciones base macrocelulares por el despliegue de femtoceldas, pero necesitan desplegarse en zonas con una densidad de población relativamente elevada para que éstas descarguen tráfico de varios usuarios de la red macrocelular simultáneamente. No obstante, las femtoceldas son beneficiosas en todo caso si es el usuario quien asume los costes de la femtocelda y el backhaul, lo que sólo parece probable si se integran en el modelo de negocio de comercialización de nuevos servicios. Por tanto, el despliegue de femtoceldas en buena parte de la casuística estudiada sólo tiene sentido si consiguen aumentar los ingresos por usuario comercializando servicios de valor añadido que necesiten calidad de servicio garantizada y exploten a la vez de esa forma su principal ventaja competitiva respecto a la tecnología WiFi. Finalmente, en relación con el papel de la tecnología LTE para la provisión de servicios de acceso fijo inalámbrico para la banda ancha de 30 Mbps, se ha desarrollado un modelo TD-LTE y mediante la metodología de análisis tecnoeconómico se ha realizado un estudio prospectivo para el caso de España. Los resultados obtenidos preciden una huella de cobertura de FTTH del 74% para 2020, y demuestran que una red TD-LTE en la banda de 3,5 GHz resulta viable para aumentar la cobertura de servicios de 30 Mbps en 14 puntos porcentuales. Junto con la consideración de la cobertura de otras redes, la cobertura de 30 Mbps de acuerdo a la viabilidad de los despliegues alcanzaría el 95% en España en el año 2020. Como resumen, los resultados obtenidos muestran en todos los casos la capacidad de la tecnología LTE para afrontar nuevos desafíos en relación con el aumento del tráfico móvil, especialmente crítico en las zonas más urbanas, y el cierre de la brecha digital en el acceso a la banda ancha rápida en las zonas más rurales. ABSTRACT The LTE standard has been pointed out as one of the keys for telecom operators to address the demand growth in mobile traffic foreseen for the next years in a cost-efficient way, since its core network is more scalable and its radio interface more flexible than those of its predecessor technologies. On the other hand, regulators need to guarantee an adequate, equitable and non-discriminatory access to radio spectrum, which enable a favorable environment for the deployment of advanced mobile communication networks. Despite the reform of the spectrum regulatory framework in Europe, which allowed for the deployment of new technologies in the historic GSM bands, additional spectrum has been allocated to IMT systems in new frequency bands, what in turn has set out new challenges for technology and regulation. The current fragmentation of available spectrum in very different frequency bands has boosted the development of carrier aggregation techniques in most recent releases of the LTE standard, which permit a better exploitation of radio resources as a whole. Nonetheless, spectrum below 1 GHz is still scarce for mobile networks, since mobile traffic increases at a more rapid pace than spectral efficiency and spectrum resources. The 900 MHz frequency band is still being used for GSM services, what has worsen the dispute between mobile communication services and terrestrial broadcasting services for the upper part of the UHF band. Concretely, the 700 MHz frequency band has been pointed out as one of the next bands to be allocated to mobile in order to increase available spectrum. However, its release by current Digital Terrestrial Television networks is challenging in Member States where it constitutes the main free access audiovisual platform, opening up a new debate around the audiovisual model in the long term in Europe. On the other hand, public policies of the present decade to promote fast and ultrafast broadband access has established very ambitious objectives for the year 2020, both at European and national levels. Universalization of 30 Mbps broadband access networks constitutes one of the main challenges. Expectations raised by LTE technology and the allocation of new frequency bands has lead fixed wireless access (FWA) services to acquire special relevance in light of public policy objectives, which will not be met but with a compendium of different technologies, as different involved stakeholders have acknowledged. This PhD Dissertation develops techno-economic models to carry out a prospective analysis for three cases of special relevance in LTE networks’ deployment: the spectrum pricing of the 700 MHz frequency band, an assessment of new business models and cost reduction considering femtocell technologies, and the feasibility of LTE fixed wireless access networks to close the 30 Mbps broadband access gap in rural areas. In the first place and regarding the application of techno-economic analysis for 700 MHz spectrum pricing, obtained results reveal two core issues. First of all, the need to allocate more spectrum for operators in order to fulfill mobile traffic demand in the mid-term. Secondly, there is a substantial difference in deployment costs for a LTE network when there is sub-1GHz spectrum available and when there is not, but this difference decreases as additional sub-1GHz spectrum is added. Thus, the allocation of 700 MHz band to mobile communication services would cause a relevant reduction in deployment costs if the operator does not count on spectrum in the 800 MHz, but not if it already has been assigned spectrum in low frequencies for the deployment. In this regard, the price operators will be willing to pay for 700 MHz spectrum will depend on them having already spectrum in the 800 MHz frequency band or not. However, since competition for the new spectrum will not be so strong, expected incomes from 700 MHz spectrum awards will be generally lower than those from the digital dividend, despite this spectrum being as valuable as 800 MHz spectrum for some operators. In the second place, regarding femtocell deployment, some conclusions can be drawn in terms of deployment cost savings and also with reference to the business model they enable. Savings provided by a joint macro-femto LTE network as compared to an exclusively macrocellular deployment increase as the available bandwidth for the macrocells decreases. Therefore, for a convergent operator the deployment of femtocells can only have economic sense if the available bandwidth is scarce (around 2x10 MHz), which might be the case of fix market operators which are new entrant in mobile market. Besides, open access models are interesting for exclusively mobile operators, since they make costs more flexible by substituting macrocell base stations by femtocells, but they need to be deployed relatively densely populated areas so that they can offload traffic from several macrocell users simultaneously. Nonetheless, femtocells are beneficial in all cases if the user assumes both femtocell and backhaul costs, which only seems probable if they are integrated in a business model commercializing new services. Therefore, in many of the cases analyzed femtocell deployment only makes sense if they increase revenues per user through new added value services which need from guaranteed quality of service, thus exploiting its main competitive advantage compared to WiFi. Finally, regarding the role of LTE technology in the provision of fixed wireless access services for 30 Mbps broadband, a TD-LTE model has been developed and a prospective study has been carried out through techno-economic methodology for the Spanish case. Obtained results foresee a FTTH coverage footprint of 74% households for 2020, and prove that a TD-LTE network in the 3.5 GHz band results feasible to increase 30 Mbps service coverage in additional 14 percentage points. To sum up, obtained results show LTE technology capability to address new challenges regarding both mobile traffic growth, particularly critical in urban zones, and the current digital divide in fast broadband access in most rural zones.

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Esta tese buscou estudar a integração entre a prospecção do futuro e projetos dentro do escopo da estratégia. Decisões envolvendo projetos no âmbito da estratégia das organizações são para horizontes de tempo de médio ou longo prazo. Nessa situação, gestores precisam lidar com incertezas de futuro, e para isso podem recorrer às metodologias de prospecção do futuro. O estudo do futuro é atividade complexa, pela abrangência de temas a serem considerados, contudo, é provável que gestores pratiquem essa atividade devido à responsabilidade assumida por suas decisões. A prática de metodologia prospectiva gera resultados, e estes podem contribuir nas decisões em projetos estratégicos. A literatura de estudos do futuro contém recomendações sobre como praticar metodologia prospectiva, porém aborda menos a utilização dos resultados de estudos prospectivos e a sua contribuição para a estratégia empresarial. Ela se concentra mais nos processos de desenvolvimento dos projetos de prospecção para se chegar aos resultados. Dessa forma, esta tese visou ao estudo da utilização dos resultados da prospecção nas decisões de projetos no âmbito da estratégia empresarial. Os fenômenos estudados envolvem a transição entre a prática da prospecção do futuro, a consequente disponibilidade de seus resultados e a contribuição dos mesmos nos processos de análise prospectiva para suporte a decisões. O objetivo geral da tese é a proposta de um modelo que contribua nessa transição. A metodologia utilizada foi mista - quantitativa e qualitativa - desenvolvida por meio de survey e entrevistas, e a abordagem utilizada foi exploratória e descritiva. Os resultados indicam haver limitações na integração entre prospecção do futuro e estratégia empresarial. Foi identificado que a prospecção do futuro é considerada importante pelos gestores participantes da pesquisa. Em contraste, a transição para a sua prática, passando pela disponibilidade de seus resultados, e a posterior utilização deles em processos de suporte à tomada de decisões em projetos estratégicos, apresenta limitações. Os resultados indicam que, apesar da importância da atividade de prospecção, gestores avaliam que ela é praticada em um nível mais baixo, e ao final a contribuição de seus resultados é avaliada em nível ainda mais baixo. Isso é mais evidente nas empresas de menor quantidade de funcionários, menor faturamento, de capital fechado ou limitado, sendo que nessas empresas a prospecção é para horizonte de tempo mais curto. Já gestores de empresas com maior quantidade de funcionários, maior faturamento e de capital aberto lidam melhor com a prospecção do futuro, sendo que estudam seus projetos estratégicos em horizonte de tempo mais longo. Observou-se que as principais limitações identificadas estão relacionadas com o conhecimento das metodologias de prospecção do futuro, e isso limita principalmente a identificação de temas importantes a serem estudados e monitorados acerca do futuro, configurando-se como lacunas de análise prospectiva ou pontos cegos. Por decorrência disso, a contribuição da prospecção na estratégia empresarial sofre limitações. Conclui-se, portanto, que a integração entre prospecção do futuro e a estratégia empresarial poderia ser facilitada por meio do uso de um modelo de suporte, voltado para: (1) reduzir a possibilidade de lacunas de análise prospectiva; e (2) suportar a avaliação: da prática da prospecção do futuro, do uso dos seus resultados nas decisões, e finalmente da aplicação da expertise sobre prospecção do futuro na empresa. Os resultados confirmam que o modelo proposto contribuiria na integração da prospecção do futuro com a estratégia empresarial.

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Epitope prediction is becoming a key tool for vaccine discovery. Prospective analysis of bacterial and viral genomes can identify antigenic epitopes encoded within individual genes that may act as effective vaccines against specific pathogens. Since B-cell epitope prediction remains unreliable, we concentrate on T-cell epitopes, peptides which bind with high affinity to Major Histacompatibility Complexes (MHC). In this report, we evaluate the veracity of identified T-cell epitope ensembles, as generated by a cascade of predictive algorithms (SignalP, Vaxijen, MHCPred, IDEB, EpiJen), as a candidate vaccine against the model pathogen uropathogenic gram negative bacteria Escherichia coli (E-coli) strain 536 (O6:K15:H31). An immunoinformatic approach was used to identify 23 epitopes within the E-coli proteome. These epitopes constitute the most promiscuous antigenic sequences that bind across more than one HLA allele with high affinity (IC50 <50nM). The reliability of software programmes used, polymorphic nature of genes encoding MHC and what this means for population coverage of this potential vaccine are discussed.

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Aims: Specialist lifestyle management (SLiM) is a medically supported dietetically led structured group education and self-management programme focusing on weight management. Obese patients with Type 2 diabetes are perceived to find it more difficult to lose weight compared with those without diabetes. We aimed to compare the weight loss achieved by obese patients with or without Type 2 diabetes completing the SLiM programme. Methods: A prospective analysis of patients attending SLiM between 2009 and 2013 was conducted. Results: There were 454 obese patients (mean age 49.1 ± 11.6years, women 72.5%, body mass index 49.8 ± 9.3kg/m2, weight137.3 ± 28kg). 152/454 patients (33%) had Type 2 diabetes of which 31 (20.4%) were insulin treated. Patients with Type 2diabetes were older (52.4 ± 11.3 vs 47.5 ± 11.4 years, p < 0.001). SLiM resulted in significant weight loss in patients with (136.5 ± 27 vs 130.2 ± 25.3, p < 0.001) or without (137.6 ± 29 vs 132.6 ± 28.4, p < 0.001) Type 2 diabetes. Weight loss was comparable between patients with and without Type 2 diabetes (6.1 ± 7.9 vs5.1 ± 7kg, p = 0.2). The proportion of patients achieving ≥ 10%weight loss was similar between patients with and without Type 2diabetes (10.5% vs 9.9%, p = 0.4). Insulin-treated patients lost similar weight to those not treated with insulin (6.3 ± 9.4 vs 6.1 ± 7.6kg, p = 0.9). After adjustment for age, sex, referral weight and medications, Type 2 diabetes did not predict weight change during the SLiM programme (b = 0.3, p = 0.5). Conclusions: Attending the SLiM groups produces a significant weight loss in patients with Type 2 diabetes which is comparable to those without Type 2 diabetes. Insulin-treated patients lost similar weight to those not on insulin. Weight gain with Type 2 diabetes and insulin treatment is not ‘unavoidable’ if patients receive the appropriate support and education.