918 resultados para The Burnet Institute


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Los arrays de ranuras son sistemas de antennas conocidos desde los años 40, principalmente destinados a formar parte de sistemas rádar de navíos de combate y grandes estaciones terrenas donde el tamaño y el peso no eran altamente restrictivos. Con el paso de los años y debido sobre todo a importantes avances en materiales y métodos de fabricación, el rango de aplicaciones de este tipo de sistemas radiantes creció en gran medida. Desde nuevas tecnologías biomédicas, sistemas anticolisión en automóviles y navegación en aviones, enlaces de comunicaciones de alta tasa binaria y corta distancia e incluso sistemas embarcados en satélites para la transmisión de señal de televisión. Dentro de esta familia de antennas, existen dos grupos que destacan por ser los más utilizados: las antennas de placas paralelas con las ranuras distribuidas de forma circular o espiral y las agrupaciones de arrays lineales construidos sobre guia de onda. Continuando con las tareas de investigación desarrolladas durante los últimos años en el Instituto de Tecnología de Tokyo y en el Grupo de Radiación de la Universidad Politécnica de Madrid, la totalidad de esta tesis se centra en este último grupo, aunque como se verá se separa en gran medida de las técnicas de diseño y metodologías convencionales. Los arrays de ranuras rectas y paralelas al eje de la guía rectangular que las alimenta son, sin ninguna duda, los modelos más empleados debido a la fiabilidad que presentan a altas frecuencias, su capacidad para gestionar grandes cantidades de potencia y la sencillez de su diseño y fabricación. Sin embargo, también presentan desventajas como estrecho ancho de banda en pérdidas de retorno y rápida degradación del diagrama de radiación con la frecuencia. Éstas son debidas a la naturaleza resonante de sus elementos radiantes: al perder la resonancia, el sistema global se desajusta y sus prestaciones degeneran. En arrays bidimensionales de slots rectos, el campo eléctrico queda polarizado sobre el plano transversal a las ranuras, correspondiéndose con el plano de altos lóbulos secundarios. Esta tesis tiene como objetivo el desarrollo de un método sistemático de diseño de arrays de ranuras inclinadas y desplazadas del centro (en lo sucesivo “ranuras compuestas”), definido en 1971 como uno de los desafíos a superar dentro del mundo del diseño de antennas. La técnica empleada se basa en el Método de los Momentos, la Teoría de Circuitos y la Teoría de Conexión Aleatoria de Matrices de Dispersión. Al tratarse de un método circuital, la primera parte de la tesis se corresponde con el estudio de la aplicabilidad de las redes equivalentes fundamentales, su capacidad para recrear fenómenos físicos de la ranura, las limitaciones y ventajas que presentan para caracterizar las diferentes configuraciones de slot compuesto. Se profundiza en las diferencias entre las redes en T y en ! y se condiciona la selección de una u otra dependiendo del tipo de elemento radiante. Una vez seleccionado el tipo de red a emplear en el diseño del sistema, se ha desarrollado un algoritmo de cascadeo progresivo desde el puerto alimentador hacia el cortocircuito que termina el modelo. Este algoritmo es independiente del número de elementos, la frecuencia central de funcionamiento, del ángulo de inclinación de las ranuras y de la red equivalente seleccionada (en T o en !). Se basa en definir el diseño del array como un Problema de Satisfacción de Condiciones (en inglés, Constraint Satisfaction Problem) que se resuelve por un método de Búsqueda en Retroceso (Backtracking algorithm). Como resultado devuelve un circuito equivalente del array completo adaptado a su entrada y cuyos elementos consumen una potencia acorde a una distribución de amplitud dada para el array. En toda agrupación de antennas, el acoplo mutuo entre elementos a través del campo radiado representa uno de los principales problemas para el ingeniero y sus efectos perjudican a las prestaciones globales del sistema, tanto en adaptación como en capacidad de radiación. El empleo de circuito equivalente se descartó por la dificultad que suponía la caracterización de estos efectos y su inclusión en la etapa de diseño. En esta tesis doctoral el acoplo también se ha modelado como una red equivalente cuyos elementos son transformadores ideales y admitancias, conectada al conjunto de redes equivalentes que representa el array. Al comparar los resultados estimados en términos de pérdidas de retorno y radiación con aquellos obtenidos a partir de programas comerciales populares como CST Microwave Studio se confirma la validez del método aquí propuesto, el primer método de diseño sistemático de arrays de ranuras compuestos alimentados por guía de onda rectangular. Al tratarse de ranuras no resonantes, el ancho de banda en pérdidas de retorno es mucho mas amplio que el que presentan arrays de slots rectos. Para arrays bidimensionales, el ángulo de inclinación puede ajustarse de manera que el campo quede polarizado en los planos de bajos lóbulos secundarios. Además de simulaciones se han diseñado, construido y medido dos prototipos centrados en la frecuencia de 12GHz, de seis y diez elementos. Las medidas de pérdidas de retorno y diagrama de radiación revelan excelentes resultados, certificando la bondad del método genuino Method of Moments - Forward Matching Procedure desarrollado a lo largo de esta tésis. Abstract The slot antenna arrays are well known systems from the decade of 40s, mainly intended to be part of radar systems of large warships and terrestrial stations where size and weight were not highly restrictive. Over the years, mainly due to significant advances in materials and manufacturing methods, the range of applications of this type of radiating systems grew significantly. From new biomedical technologies, collision avoidance systems in cars and aircraft navigation, short communication links with high bit transfer rate and even embedded systems in satellites for television broadcast. Within this family of antennas, two groups stand out as being the most frequent in the literature: parallel plate antennas with slots placed in a circular or spiral distribution and clusters of waveguide linear arrays. To continue the vast research work carried out during the last decades in the Tokyo Institute of Technology and in the Radiation Group at the Universidad Politécnica de Madrid, this thesis focuses on the latter group, although it represents a technique that drastically breaks with traditional design methodologies. The arrays of slots straight and parallel to the axis of the feeding rectangular waveguide are without a doubt the most used models because of the reliability that they present at high frequencies, its ability to handle large amounts of power and their simplicity of design and manufacturing. However, there also exist disadvantages as narrow bandwidth in return loss and rapid degradation of the radiation pattern with frequency. These are due to the resonant nature of radiating elements: away from the resonance status, the overall system performance and radiation pattern diminish. For two-dimensional arrays of straight slots, the electric field is polarized transverse to the radiators, corresponding to the plane of high side-lobe level. This thesis aims to develop a systematic method of designing arrays of angled and displaced slots (hereinafter "compound slots"), defined in 1971 as one of the challenges to overcome in the world of antenna design. The used technique is based on the Method of Moments, Circuit Theory and the Theory of Scattering Matrices Connection. Being a circuitry-based method, the first part of this dissertation corresponds to the study of the applicability of the basic equivalent networks, their ability to recreate the slot physical phenomena, their limitations and advantages presented to characterize different compound slot configurations. It delves into the differences of T and ! and determines the selection of the most suitable one depending on the type of radiating element. Once the type of network to be used in the system design is selected, a progressive algorithm called Forward Matching Procedure has been developed to connect the proper equivalent networks from the feeder port to shorted ending. This algorithm is independent of the number of elements, the central operating frequency, the angle of inclination of the slots and selected equivalent network (T or ! networks). It is based on the definition of the array design as a Constraint Satisfaction Problem, solved by means of a Backtracking Algorithm. As a result, the method returns an equivalent circuit of the whole array which is matched at its input port and whose elements consume a power according to a given amplitude distribution for the array. In any group of antennas, the mutual coupling between elements through the radiated field represents one of the biggest problems that the engineer faces and its effects are detrimental to the overall performance of the system, both in radiation capabilities and return loss. The employment of an equivalent circuit for the array design was discarded by some authors because of the difficulty involved in the characterization of the coupling effects and their inclusion in the design stage. In this thesis the coupling has also been modeled as an equivalent network whose elements are ideal transformers and admittances connected to the set of equivalent networks that represent the antennas of the array. By comparing the estimated results in terms of return loss and radiation with those obtained from popular commercial software as CST Microwave Studio, the validity of the proposed method is fully confirmed, representing the first method of systematic design of compound-slot arrays fed by rectangular waveguide. Since these slots do not work under the resonant status, the bandwidth in return loss is much wider than the longitudinal-slot arrays. For the case of two-dimensional arrays, the angle of inclination can be adjusted so that the field is polarized at the low side-lobe level plane. Besides the performed full-wave simulations two prototypes of six and ten elements for the X-band have been designed, built and measured, revealing excellent results and agreement with the expected results. These facts certify that the genuine technique Method of Moments - Matching Forward Procedure developed along this thesis is valid and trustable.

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Until recently, cinematographic film was largely cellulose-triacetate-based. However, this material is highly susceptible to biodeterioration, thus placing historic film collections, an important part of the cultural heritage of many countries, at risk. In the present study, samples taken from several biodeteriorated color cinematographic films belonging to the collection of the Cuban Institute for Cinematographic Industry and Arts (ICAIC) were investigated. Infrared spectroscopy showed that all films were of the same composition, i.e., a gelatin emulsion coating one side of a cellulose-triacetate-based film support. The films were analyzed by environmental scanning electron microscopy and scanning electron microscopy to determine the degree of biodeterioration and the type of colonizing microorganisms. Significant fungal colonization was found on both sides of the films in all samples, with a higher concentration of fungi on the gelatin emulsion side. Epifluorescence microscopy of fluorochrome-dyed films demonstrated that some of the fungi were still active, indicating that the films under study, and probably others at the ICAIC, are at risk of further deterioration. Fungi were identified by molecular biology techniques. The fungi mainly responsible for the observed biodeterioration were those belonging to the genera Aspergillus and Cladosporium, although other genera, such as Microascus and Penicillium, were identified as well. In accordance with the findings described herein, the existing guidelines for the prevention and control of film biodeterioration are discussed.

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An analysis of the structure of flame balls encountered under microgravity conditions, which are stable due to radiant energy losses from H₂O, is carried out for fuel-lean hydrogen-air mixtures. It is seen that, because of radiation losses, in stable flame balls the maximum flame temperature remains close to the crossover temperature, at which the rate of the branching step H + O₂ -> OH + O equals that of the recombination step H + O₂ + M -> HO₂ + M. Under those conditions, all chemical intermediates have very small concentrations and follow the steady-state approximation, while the main species react according to the overall step 2H₂ + O₂-> 2H₂O; so that a one-step chemical-kinetic description, recently derived by asymptotic analysis for near-limit fuel-lean deflagrations, can be used with excellent accuracy to describe the whole branch of stable flame balls. Besides molecular diffusion in a binary-diffusion approximation, Soret diffusion is included, since this exerts a nonnegligible effect to extend the flammability range. When the large value of the activation energy of the overall reaction is taken into account, the leading-order analysis in the reaction-sheet approximation is seen to determine the flame ball radius as that required for radiant heat losses to remove enough of the heat released by chemical reaction at the flame to keep the flame temperature at a value close to crossover. The results are relevant to burning velocities at lean equivalent ratios and may influence fire-safety issues associated with hydrogen utilization.

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According to the PMBOK (Project Management Body of Knowledge), project management is “the application of knowledge, skills, tools, and techniques to project activities to meet the project requirements” [1]. Project Management has proven to be one of the most important disciplines at the moment of determining the success of any project [2][3][4]. Given that many of the activities covered by this discipline can be said that are “horizontal” for any kind of domain, the importance of acknowledge the concepts and practices becomes even more obvious. The specific case of the projects that fall in the domain of Software Engineering are not the exception about the great influence of Project Management for their success. The critical role that this discipline plays in the industry has come to numbers. A report by McKinsey & Co [4] shows that the establishment of programs for the teaching of critical skills of project management can improve the performance of the project in time and costs. As an example of the above, the reports exposes: “One defense organization used these programs to train several waves of project managers and leaders who together administered a portfolio of more than 1,000 capital projects ranging in Project management size from $100,000 to $500 million. Managers who successfully completed the training were able to cut costs on most projects by between 20 and 35 percent. Over time, the organization expects savings of about 15 percent of its entire baseline spending”. In a white paper by the PMI (Project Management Institute) about the value of project management [5], it is stated that: “Leading organizations across sectors and geographic borders have been steadily embracing project management as a way to control spending and improve project results”. According to the research made by the PMI for the paper, after the economical crisis “Executives discovered that adhering to project management methods and strategies reduced risks, cut costs and improved success rates—all vital to surviving the economic crisis”. In every elite company, a proper execution of the project management discipline has become a must. Several members of the software industry have putted effort into achieving ways of assuring high quality results from projects; many standards, best practices, methodologies and other resources have been produced by experts from different fields of expertise. In the industry and the academic community, there is a continuous research on how to teach better software engineering together with project management [4][6]. For the general practices of Project Management the PMI produced a guide of the required knowledge that any project manager should have in their toolbox to lead any kind of project, this guide is called the PMBOK. On the side of best practices 10 and required knowledge for the Software Engineering discipline, the IEEE (Institute of Electrical and Electronics Engineers) developed the SWEBOK (Software Engineering Body of Knowledge) in collaboration with software industry experts and academic researchers, introducing into the guide many of the needed knowledge for a 5-year expertise software engineer [7]. The SWEBOK also covers management from the perspective of a software project. This thesis is developed to provide guidance to practitioners and members of the academic community about project management applied to software engineering. The way used in this thesis to get useful information for practitioners is to take an industry-approved guide for software engineering professionals such as the SWEBOK, and compare the content to what is found in the PMBOK. After comparing the contents of the SWEBOK and the PMBOK, what is found missing in the SWEBOK is used to give recommendations on how to enrich project management skills for a software engineering professional. Recommendations for members of the academic community on the other hand, are given taking into account the GSwE2009 (Graduated Software Engineering 2009) standard [8]. GSwE2009 is often used as a main reference for software engineering master programs [9]. The standard is mostly based on the content of the SWEBOK, plus some contents that are considered to reinforce the education of software engineering. Given the similarities between the SWEBOK and the GSwE2009, the results of comparing SWEBOK and PMBOK are also considered valid to enrich what the GSwE2009 proposes. So in the end the recommendations for practitioners end up being also useful for the academic community and their strategies to teach project management in the context of software engineering.

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La gestión de los residuos radiactivos de vida larga producidos en los reactores nucleares constituye uno de los principales desafíos de la tecnología nuclear en la actualidad. Una posible opción para su gestión es la transmutación de los nucleidos de vida larga en otros de vida más corta. Los sistemas subcríticos guiados por acelerador (ADS por sus siglas en inglés) son una de las tecnologías en desarrollo para logar este objetivo. Un ADS consiste en un reactor nuclear subcrítico mantenido en un estado estacionario mediante una fuente externa de neutrones guiada por un acelerador de partículas. El interés de estos sistemas radica en su capacidad para ser cargados con combustibles que tengan contenidos de actínidos minoritarios mayores que los reactores críticos convencionales, y de esta manera, incrementar las tasas de trasmutación de estos elementos, que son los principales responsables de la radiotoxicidad a largo plazo de los residuos nucleares. Uno de los puntos clave que han sido identificados para la operación de un ADS a escala industrial es la necesidad de monitorizar continuamente la reactividad del sistema subcrítico durante la operación. Por esta razón, desde los años 1990 se han realizado varios experimentos en conjuntos subcríticos de potencia cero (MUSE, RACE, KUCA, Yalina, GUINEVERE/FREYA) con el fin de validar experimentalmente estas técnicas. En este contexto, la presente tesis se ocupa de la validación de técnicas de monitorización de la reactividad en el conjunto subcrítico Yalina-Booster. Este conjunto pertenece al Joint Institute for Power and Nuclear Research (JIPNR-Sosny) de la Academia Nacional de Ciencias de Bielorrusia. Dentro del proyecto EUROTRANS del 6º Programa Marco de la UE, en el año 2008 se ha realizado una serie de experimentos en esta instalación concernientes a la monitorización de la reactividad bajo la dirección del CIEMAT. Se han realizado dos tipos de experimentos: experimentos con una fuente de neutrones pulsada (PNS) y experimentos con una fuente continua con interrupciones cortas (beam trips). En el caso de los primeros, experimentos con fuente pulsada, existen dos técnicas fundamentales para medir la reactividad, conocidas como la técnica del ratio bajo las áreas de los neutrones inmediatos y retardados (o técnica de Sjöstrand) y la técnica de la constante de decaimiento de los neutrones inmediatos. Sin embargo, varios experimentos han mostrado la necesidad de aplicar técnicas de corrección para tener en cuenta los efectos espaciales y energéticos presentes en un sistema real y obtener valores precisos de la reactividad. En esta tesis, se han investigado estas correcciones mediante simulaciones del sistema con el código de Montecarlo MCNPX. Esta investigación ha servido también para proponer una versión generalizada de estas técnicas donde se buscan relaciones entre la reactividad el sistema y las cantidades medidas a través de simulaciones de Monte Carlo. El segundo tipo de experimentos, experimentos con una fuente continua e interrupciones del haz, es más probable que sea empleado en un ADS industrial. La versión generalizada de las técnicas desarrolladas para los experimentos con fuente pulsada también ha sido aplicada a los resultados de estos experimentos. Además, el trabajo presentado en esta tesis es la primera vez, en mi conocimiento, en que la reactividad de un sistema subcrítico se monitoriza durante la operación con tres técnicas simultáneas: la técnica de la relación entre la corriente y el flujo (current-to-flux), la técnica de desconexión rápida de la fuente (source-jerk) y la técnica del decaimiento de los neutrones inmediatos. Los casos analizados incluyen la variación rápida de la reactividad del sistema (inserción y extracción de las barras de control) y la variación rápida de la fuente de neutrones (interrupción larga del haz y posterior recuperación). ABSTRACT The management of long-lived radioactive wastes produced by nuclear reactors constitutes one of the main challenges of nuclear technology nowadays. A possible option for its management consists in the transmutation of long lived nuclides into shorter lived ones. Accelerator Driven Subcritical Systems (ADS) are one of the technologies in development to achieve this goal. An ADS consists in a subcritical nuclear reactor maintained in a steady state by an external neutron source driven by a particle accelerator. The interest of these systems lays on its capacity to be loaded with fuels having larger contents of minor actinides than conventional critical reactors, and in this way, increasing the transmutation rates of these elements, that are the main responsible of the long-term radiotoxicity of nuclear waste. One of the key points that have been identified for the operation of an industrial-scale ADS is the need of continuously monitoring the reactivity of the subcritical system during operation. For this reason, since the 1990s a number of experiments have been conducted in zero-power subcritical assemblies (MUSE, RACE, KUCA, Yalina, GUINEVERE/FREYA) in order to experimentally validate these techniques. In this context, the present thesis is concerned with the validation of reactivity monitoring techniques at the Yalina-Booster subcritical assembly. This assembly belongs to the Joint Institute for Power and Nuclear Research (JIPNR-Sosny) of the National Academy of Sciences of Belarus. Experiments concerning reactivity monitoring have been performed in this facility under the EUROTRANS project of the 6th EU Framework Program in year 2008 under the direction of CIEMAT. Two types of experiments have been carried out: experiments with a pulsed neutron source (PNS) and experiments with a continuous source with short interruptions (beam trips). For the case of the first ones, PNS experiments, two fundamental techniques exist to measure the reactivity, known as the prompt-to-delayed neutron area-ratio technique (or Sjöstrand technique) and the prompt neutron decay constant technique. However, previous experiments have shown the need to apply correction techniques to take into account the spatial and energy effects present in a real system and thus obtain accurate values for the reactivity. In this thesis, these corrections have been investigated through simulations of the system with the Monte Carlo code MCNPX. This research has also served to propose a generalized version of these techniques where relationships between the reactivity of the system and the measured quantities are obtained through Monte Carlo simulations. The second type of experiments, with a continuous source with beam trips, is more likely to be employed in an industrial ADS. The generalized version of the techniques developed for the PNS experiments has also been applied to the result of these experiments. Furthermore, the work presented in this thesis is the first time, to my knowledge, that the reactivity of a subcritical system has been monitored during operation simultaneously with three different techniques: the current-to-flux, the source-jerk and the prompt neutron decay techniques. The cases analyzed include the fast variation of the system reactivity (insertion and extraction of a control rod) and the fast variation of the neutron source (long beam interruption and subsequent recovery).

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The preservation of tangible cultural heritage does not guarantee effective revitalisation of urban historic areas as a whole. The legacy of our history consists not only of paintings, sculptures, architectural monuments and public spaces, but also the safeguarding of immaterial aspects of social life, such as oral traditions, rituals, practices, knowledge and craft skills. From 1999 to 2013, 26 Brazilian cities benefited from the Monumenta Programme - a national cultural policy that involved institutions, the private sector and the local community. The purpose of the programme was to stimulate economic growth and increase cultural and social development of the historic centres. Moreover, it sought to increase the number of residents in the benefited areas as defined in its agenda (IDB, 1999; MinC & Programa Monumenta, 2006). Using the Historic Centre of Porto Alegre as a case study, this paper examines how this cultural programme enables demographic change through the promotion of intangible cultural heritage, e.g. by supporting educational projects. The demographic flow was analysed using the microdata of the Populations Censuses (years 2000 and 2010) available from the Brazilian Institute of Geography and Statistics. The results showed an increase in low-income residents the areas that participated in the programme. This increase may have been motivated by a set of cultural-educational projects under the auspices of the Monumenta Programme. The retraining of artisans of Alfândega Square, the training of low-income youth for restoration work and the implementation of the "Black Route Museum in Porto Alegre" (Bicca, 2010) are just some examples of what was done to improve the local community's economy, to encourage social cohesion and to enhance the awareness of cultural diversity as a positive and essential value in society.

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The Illinois Institute of Technology (iit) campus, Chicago, by architect Ludwig Mies van der Rohe, is often considered as a transitional work, usually acknowledged as significant for the reorientation of his professional career after he emigrated to the United States. Moreover, its favorable recognition today is somehow indicative of its relevance as a model for urban intervention in the contemporary American city and for contemporary city planning in general, not to mention the profound impact that it had on the cityscape of Chicago. However, today we know it was rather the result of a close collaboration between he and Ludwig Hilberseimer —later on, to be completed with Alfred Caldwell— who merged their personal ideas and expertise in the design for the first time. In addition to this, when one tries to locate the design within its own historical context and evaluate the sources of its approach to it, some contradictions arise. The major impact of the images produced by Mies to promote its realization —widely disseminated in most contemporary architectural periodicals— probably outshined the particular circumstances in which the design was conceived. In fact, it would never be materialized as originally presented, but it was, instead, continuously reworked according to land availability in the site —a circumstance often ignored by subsequent architectural critic, that enthusiastically praised the design even before it was fully completed. One of the main consequences of looking at iit from such a standpoint is that, when historically contextualized, one can appreciate that, due to the urban scale of its implementation process, the design had to face a complex reality very different to that initially planned by the architect, often far from his actual possibilities of intervention. Such approach is in contradiction with the common description of the design as a ‘tabula rasa’ that allegedly would have been formulated on the basis of a full denial of its context. On the contrary, the ever-changing circumstances of the design motivated a necessary re-interpretation of the relation between its executed fragments, in order to keep the original identity of the whole in an ever-changing context. This situation implied a continuous transformation of the design by means of a steady re-composition of its elements: as the number of completed buildings increased in its successive stages, their relation to their site-specific context changed, in a very particular process that these lines try to delineate. Requiring decades to be erected, neither of its authors would ever see the design finished as planned, partially because of the difficulties in acquiring the extension of land that it required. Considering the study of this process as able to provide a valuable gateway to understand the urban discourse that the architects entailed, the aim of these lines is to analyze the problems that the iit campus design had to face. As a starting point, a relationship between practice and theory in the activity of the authors implied in iit campus design has been assumed. Far from being interrupted during World War ii, strong historical evidence can be found to infer that both were developed in parallel. Consequently, the historical sequence of the preserved testimonies has been put into context, as well as their transformation while Mies remained in charge for the campus Master Plan. Notably, when seen from this perspective, some ideas already expressed during his previous European practice were still present during the design process. Particularly, Mies's particular understanding of certain architectural concepts — such as those of ‘order’ and ‘structure’—can be traced paralleling the theories about urban planning from his collaborators, a fact that possibly facilitated the campus successful development. The study of the way these ideas were actually redeveloped and modified in the American urban context, added to the specific process of the implementation of iit campus design, sheds a new light for a critical interpretation of the reasons that made it possible, and of the actual responsibility of Mies's collaborators in its overall development and final completion. RESUMEN El campus del Illinois Institute of Technology (iit) de Chicago, obra del arquitecto Ludwig Mies van der Rohe, es a menudo considerado como una obra de transición que, por lo general, ha venido siendo reconocida como relevante para la reorientación de su carrera profesional posterior a su exilio en los Estados Unidos. El reconocimiento del que goza el proyecto es indicativo, de algún modo, de su importancia como modelo para la intervención urbana en la ciudad norteamericana contemporánea y el planeamiento de la ciudad contemporánea en general, sin olvidar el profundo impacto que ha tenido sobre el paisaje urbano de Chicago. Sin embargo, hoy sabemos que el resultado se benefició de su estrecha colaboración con Ludwig Hilberseimer y se completaría más tarde con la de Alfred Caldwell, quienes unieron sus ideas y experiencia profesional en el proyecto por primera vez. Asimismo, cuando se intenta ubicar el proyecto dentro de su propio contexto histórico y evaluar los criterios de su manera de abordarlo, surgen algunas contradicciones. El considerable impacto de las imágenes producidas por Mies para impulsar su ejecución —ampliamente difundidas en la mayoría de publicaciones de arquitectura de la época— probablemente eclipsó las particulares circunstancias en las que el proyecto fue concebido. De hecho, nunca llegó a materializarse tal y como fue inicialmente presentado. Por contra, fue reelaborado de manera continua, de acuerdo a la disponibilidad de suelo en el emplazamiento; una circunstancia a menudo ignorada por la crítica posterior, que elogió con entusiasmo el proyecto antes siquiera de que fuese terminado. Una de las principales consecuencias de contemplar el iit desde semejante punto de vista es que, una vez contextualizada históricamente su puesta en obra, se puede apreciar que el arquitecto tuvo que enfrentarse a una compleja realidad urbana muy diferente a la inicialmente prevista —probablemente debido a la escala del proyecto— a menudo lejos de sus posibilidades reales de intervención. Este enfoque contradice la descripción habitual del proyecto como una ‘tabula rasa’, que supuestamente se habría formulado sobre la base de una negación completa de su contexto. Por el contrario, las circunstancias cambiantes del proyecto obligaron una necesaria reinterpretación de la relación entre sus frag mentos ejecutados, con el fin de mantener la identidad original del conjunto en un contexto en constante cambio. Esta situación implicó una continua transformación del proyecto por medio de una permanente re-composición de sus elementos: según se incrementaba el número de edificios construidos en las etapas sucesivas de desarrollo del conjunto, variaba su relación con el contexto específico en que se emplazaban, en un proceso muy particular que estas líneas tratan de perfilar. Al necesitar décadas para ser levantado, ninguno de sus autores vería el conjunto terminado según lo planificado, en parte debido a las dificultades para la adquisición de la extensión de suelo que demandaba. Asumiendo que el estudio de este proceso es capaz de proporcionar una valiosa puerta de entrada para elucidar el discurso urbano asumido por los Mies, el objetivo de estas líneas es analizar los problemas a los que el proyecto del campus del iit tuvo que enfrentarse. Como punto de partida, se ha supuesto una relación entre la práctica y la teoría en la actividad de los autores implicados en el proyecto del campus del iit. Lejos de interrumpirse durante la Segunda Guerra Mundial, existen evidencias históricas sólidas para deducir que ambas vertientes se desarrollaron en paralelo. En consecuencia, se ha contextualizado la secuencia histórica de los testimonios conservados, así como su transformación durante el periodo en que Mies estuvo a cargo del Plan General del campus. Significativamente, al ser contempladas bajo esta perspectiva, algunas ideas ya expresadas durante su práctica europea anterior resultan aún presentes durante la redacción del proyecto. En concreto, se puede trazar un paralelismo entre la comprensión particular de Mies de ciertos conceptos arquitectónicos —como los de ‘orden’ y ‘estructura’— y las teorías sobre el urbanismo de sus colaboradores, hecho que posiblemente facilitó el exitoso desarrollo del proyecto. El estudio de la manera en que estas ideas fueron reelaboradas y modificadas en el contexto urbano estadounidense, sumado al proceso específico de su aplicación en el proyecto del campus del iit, arroja una nueva luz para una interpretación crítica tanto de las razones que lo hicieron posible, como del papel real que los colaboradores de Mies tuvieron en su desarrollo y ejecución final.

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ACKNOWLEDGEMENTS We acknowledge the data management support of Grampian Data Safe Haven (DaSH) and the associated financial support of NHS Research Scotland, through NHS Grampian investment in the Grampian DaSH. S.S. is supported by a Clinical Research Training Fellowship from the Wellcome Trust (Ref 102729/Z/13/Z). We also acknowledge the support from The Farr Institute of Health Informatics Research. The Farr Institute is supported by a 10-funder consortium: Arthritis Research UK, the British Heart Foundation, Cancer Research UK, the Economic and Social Research Council, the Engineering and Physical Sciences Research Council, the Medical Research Council, the National Institute of Health Research, the National Institute for Social Care and Health Research (Welsh Assembly Government), the Chief Scientist Office (Scottish Government Health Directorates) and the Wellcome Trust (MRC Grant Nos: Scotland MR/K007017/1).

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Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

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IA, JNP, and MP were partly supported by the NIH, grants R01-AI-100947 to MP, and R21-GM-107683 to Matthias Chung, subcontract to MP. JNP was partly supported by an NSF graduate fellowship number DGE750616. IA, JNP, BRL, OCS and MP were supported in part by the Bill and Melinda Gates Foundation, award number 42917 to OCS. JP and AWW received core funding support from The Wellcome Trust (grant number 098051). AWW, and the Rowett Institute of Nutrition and Health, University of Aberdeen, receive core funding support from the Scottish Government Rural and Environmental Science and Analysis Service (RESAS).

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Funder statement This article/paper/report presents independent research funded by the National Institute for Health Research (NIHR). The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the UK Government’s Department of Health. Acknowledgements We would like to acknowledge Dr Graeme MacLennan, Mr Simon Skene, Mr Julian Shah and Dr Nadine Dougall (past member) for their valuable contribution to the study as DMC members. We would like to thank Professor Chris Butler, Dr Emma Hall, Mr Roland Morley, Mr Dan Wood, Ms Jane Laws and Ms Sarah Bittlestone for their oversight of the AnTIC study as members of the TSC, and we would like to thank Ms Heather Armstrong for her contributions as a patient group representative. We thank all Principal Investigators and site staff for their commitment in recruitment for the AnTIC study. Finally, we would like to thank Hazel Wilde for secretarial support. The trial is funded by the NIHR Health Technology Assessment Programme (project reference: 11-72-01) and will be published in full in the Health Technology Assessment journal series. The authors also acknowledge the support of the National Institute for Health Research through the Comprehensive Clinical Research Network.

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Acknowledgements Gokul Gopalan (a Senior Global Medical Director [Respiratory], at Teva Pharmaceuticals, Frazer, PA, US, at the time of this study), assisted with study design. Funding Funds to acquire the dataset from the Pharmo Institute for Drug Outcomes Research (Utrecht, the Netherlands) were provided by RiRL. The study received institutional support from Teva Pharmaceuticals Europe B.V. Gokul Gopalan, a Senior Global Medical Director (Respiratory), at Teva Pharmaceuticals, Frazer, PA, US, at the time of this study, assisted with study design, but neither Teva Pharmaceuticals Europe B.V. nor Teva Pharmaceuticals, Frazer, PA, US, contributed, either in part or in whole, to the collection, analysis, or interpretation of study data, manuscript writing, or the decision to submit the manuscript for publication. Erratum The original version of this article unfortunately contained errors that have since been corrected. The word “pharmo” has been fully capitalised to “PHARMO” throughout the article. The reference to Table 2 in the first and second sentence under the Outcomes heading has been replaced with Fig. 3. Under the Abbreviations heading ‘extrafine-particle’ was repeated, this has been corrected to ‘EF-HFA-BDP [Qvar®]: extrafine-particle hydrofluoroalkane beclomethasone dipropionate’. The competing interests of Nicolas Roche and Theresa Guibert have been amended. Academic affiliations for Dirkje S. Postma (2), Richard J. Martin (3), Ron M.C. Herrings (4), Jetty Overbeek (4), and Nicolas Roche (7) have been corrected. Figure 3 in the online and pdf version did not match, this been amended

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Acknowledgments Financial Support: HERU and HSRU receive a core grant from the Chief Scientist’s Office of the Scottish Government Health and Social Care Directorates, and the Centre for Clinical epidemiology & Evaluation is funded by Vancouver Coastal Health Authority. The model used for the illustrative case study in this paper was developed as part of a NHS Technology Assessment Review, funded by the National Institute for Health Research (NIHR) Health Technology Assessment Program (project number 09/146/01). The views and opinions expressed in this paper are those of the authors and do not necessarily reflect those of the Scottish Government, NHS, Vancouver Coastal Health, NIHR HTA Program or the Department of Health. The authors wish to thank Kathleen Boyd and members of the audience at the UK Health Economists Study Group, for comments received on an earlier version of this paper. We also wish to thank Cynthia Fraser (University of Aberdeen) for literature searches undertaken to inform the manuscript, and Mohsen Sadatsafavi (University of British Columbia) for comments on an earlier draft

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The National Institute of Standards and Technology (NIST) has compiled and maintained a Short Tandem Repeat DNA Internet Database (http://www.cstl.nist.gov/biotech/strbase/) since 1997 commonly referred to as STRBase. This database is an information resource for the forensic DNA typing community with details on commonly used short tandem repeat (STR) DNA markers. STRBase consolidates and organizes the abundant literature on this subject to facilitate on-going efforts in DNA typing. Observed alleles and annotated sequence for each STR locus are described along with a review of STR analysis technologies. Additionally, commercially available STR multiplex kits are described, published polymerase chain reaction (PCR) primer sequences are reported, and validation studies conducted by a number of forensic laboratories are listed. To supplement the technical information, addresses for scientists and hyperlinks to organizations working in this area are available, along with the comprehensive reference list of over 1300 publications on STRs used for DNA typing purposes.

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Social Sciences can, on occasions, be similar to the so called “hard” sciences. However, in many cases, neither the object nor the classical methods fit in with the objectives of the work. The object requires methodological and technical adjustments, which are often avoided by means of an improper rigidity of the object’s needs. These adjustments can even alter the original research idea. The main objective of this article consists of proving that those objects of study, less suitable to be addressed by rigid positivistic strategies, can be approached both scientifically and sociologically. This can be achieved with the use of different strategies and flexible methodologies to ensure validity and reliability standards. This paper will be posed, firstly, a reflection on the epistemological nature of the debate about the rigid-flexible perspectives. Secondly, the strategies and tools used by the research team to achieve the reduction of the uncertainty about the size and characteristics of the population studied will be described. Finally, some of the survey results obtained in this project will be compared to those provided by the FAMILITUR Survey (2008), conducted by the Spanish Institute of Tourist Studies (IET).