946 resultados para Complex Processes


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Withdrawal reflexes of the mollusk Aplysia exhibit sensitization, a simple form of long-term memory (LTM). Sensitization is due, in part, to long-term facilitation (LTF) of sensorimotor neuron synapses. LTF is induced by the modulatory actions of serotonin (5-HT). Pettigrew et al. developed a computational model of the nonlinear intracellular signaling and gene network that underlies the induction of 5-HT-induced LTF. The model simulated empirical observations that repeated applications of 5-HT induce persistent activation of protein kinase A (PKA) and that this persistent activation requires a suprathreshold exposure of 5-HT. This study extends the analysis of the Pettigrew model by applying bifurcation analysis, singularity theory, and numerical simulation. Using singularity theory, classification diagrams of parameter space were constructed, identifying regions with qualitatively different steady-state behaviors. The graphical representation of these regions illustrates the robustness of these regions to changes in model parameters. Because persistent protein kinase A (PKA) activity correlates with Aplysia LTM, the analysis focuses on a positive feedback loop in the model that tends to maintain PKA activity. In this loop, PKA phosphorylates a transcription factor (TF-1), thereby increasing the expression of an ubiquitin hydrolase (Ap-Uch). Ap-Uch then acts to increase PKA activity, closing the loop. This positive feedback loop manifests multiple, coexisting steady states, or multiplicity, which provides a mechanism for a bistable switch in PKA activity. After the removal of 5-HT, the PKA activity either returns to its basal level (reversible switch) or remains at a high level (irreversible switch). Such an irreversible switch might be a mechanism that contributes to the persistence of LTM. The classification diagrams also identify parameters and processes that might be manipulated, perhaps pharmacologically, to enhance the induction of memory. Rational drug design, to affect complex processes such as memory formation, can benefit from this type of analysis.

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The transition from the Oldest Dryas to the Bølling around 14,685 cal yr BP was a period of extremely rapid climatic warming. From a single core of lake marl taken at Gerzensee (Switzerland) we studied the transition in stable isotopes of oxygen and carbon on bulk sediment and charophyte remains, as well as on monospecific samples of ostracods, after Pisidium a; in addition pollen, chironomids, and Cladocera were analyzed. The δ18O record serves as an estimate of mean air temperature, and by correlation to the one from NGRIP in Greenland it provides a timescale. The timing of responses: The statistically significant zone boundaries of the biostratigraphies are telescoped at the rapid increase of about 3‰ in δ18O at the onset of Bølling. Biotic responses may have occurred within sampling resolution (8 to 16 years), although younger zone boundaries are less synchronous. Gradual and longer-lasting responses include complex processes such as primary or secular succession. During the late-glacial interstadial of Bølling and Allerød, two stronger and two weaker cool phases were found. Biological processes involved in the responses occurred on levels of individuals (e.g. pollen productivity), of populations (increases or decreases, immigration, or extinction), and on the ecosystem level (species interactions such as facilitation or competition). Abiotic and biotic interactions include pedogenesis, nitrogen-fixation, nutrient cycling, catchment hydrology, water chemistry of the lake and albedo (controlled by the transition from tundra to forest). For the Swiss Plateau this major change in vegetation induced a change in the mammal fauna, which in turn led to changes in the tool-making by Paleolithic people.

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Histomorphological features of colorectal cancers (CRC) represent valuable prognostic indicators for clinical decision making. The invasive margin is a central feature for prognostication shaped by the complex processes governing tumor-host interaction. Assessment of the tumor border can be performed on standard paraffin sections and shows promise for integration into the diagnostic routine of gastrointestinal pathology. In aggressive CRC, an extensive dissection of host tissue is seen with loss of a clear tumor-host interface. This pattern, termed "infiltrative tumor border configuration" has been consistently associated with poor survival outcome and early disease recurrence of CRC-patients. In addition, infiltrative tumor growth is frequently associated with presence of adverse clinicopathological features and molecular alterations related to aggressive tumor behavior including BRAFV600 mutation. In contrast, a well-demarcated "pushing" tumor border is seen frequently in CRC-cases with low risk for nodal and distant metastasis. A pushing border is a feature frequently associated with mismatch-repair deficiency and can be used to identify patients for molecular testing. Consequently, assessment of the tumor border configuration as an additional prognostic factor is recommended by the AJCC/UICC to aid the TNM-classification. To promote the assessment of the tumor border configuration in standard practice, consensus criteria on the defining features and method of assessment need to be developed further and tested for inter-observer reproducibility. The development of a standardized quantitative scoring system may lay the basis for verification of the prognostic associations of the tumor growth pattern in multivariate analyses and clinical trials. This article provides a comprehensive review of the diagnostic features, clinicopathological associations, and molecular alterations associated with the tumor border configuration in early stage and advanced CRC.

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With the increasing number of exoplanets discovered, statistical properties of the population as a whole become unique constraints on planet-formation models, provided a link between the description of the detailed processes playing a role in this formation and the observed population can be established. Planet population synthesis provides such a link. This approach allows us to study how different physical models of individual processes (e.g., protoplanetary disk structure and evolution, planetesimal formation, gas accretion, migration, etc.) affect the overall properties of the population of emerging planets. By necessity, planet population synthesis relies on simplified descriptions of complex processes. These descriptions can be obtained from more detailed specialized simulations of these processes. The objective of this chapter is twofold: (1) provide an overview of the physics entering in the two main approaches to planet population synthesis, and (2) present some of the results achieved as well as illustrate how it can be used to extract constraints on the models and to help interpret observations.

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The paper discusses the meaning and measurement of pro-poor growth and also reviews evidence of pro-poor growth (or the lack of it) in a large cross-section of countries and time periods. The emerging story is that many episodes of growth are not pro-poor and also that although economic reforms have had positive effects in those countries that have been steadfast in implementing market reforms, the overall impact on growth has been small for many countries and in most cases not pro-poor. I present a general theory of pro-poor growth that includes ten principles that should be incorporated in all economic reforms that seek to generate pro-poor growth. These principles highlight the importance of understanding the poor, their economic activities, capabilities, constraints that impede their participation in markets and also an appreciation of linkages within sectors and regions. It is argued that pro-poor reforms cannot have the intended impact unless there are significant changes in the institutions of governance. Finally, the principles presented underscore the fact that pro-poor growth policies cannot be sustained without workable partnerships between markets and states in the ever changing and complex processes of social and economic development.

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El objetivo de este trabajo es analizar el proceso de formulación y desarrollo de las políticas educativas durante el peronismo, teniendo en cuenta en qué medida intervinieron los actores estatales y no estatales. Nuestro ámbito de observación empírica, la provincia de Buenos Aires, nos permite dialogar con los trabajos efectuados desde un enfoque nacional. Nos interesa realizar un análisis histórico de la interacción entre estado y la sociedad, que tenga en cuenta no solo a los ejecutores sino a sus destinatarios. Se considera que los complejos procesos que rodearon la formulación de las políticas educativas durante esta etapa, se generaron en un contexto en que el gobierno provincial debió adecuar sus acciones a las presiones y demandadas no sólo de diversos actores externos, sino también de las facciones que integraban su trama política interna

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El objetivo de este trabajo es analizar el proceso de formulación y desarrollo de las políticas educativas durante el peronismo, teniendo en cuenta en qué medida intervinieron los actores estatales y no estatales. Nuestro ámbito de observación empírica, la provincia de Buenos Aires, nos permite dialogar con los trabajos efectuados desde un enfoque nacional. Nos interesa realizar un análisis histórico de la interacción entre estado y la sociedad, que tenga en cuenta no solo a los ejecutores sino a sus destinatarios. Se considera que los complejos procesos que rodearon la formulación de las políticas educativas durante esta etapa, se generaron en un contexto en que el gobierno provincial debió adecuar sus acciones a las presiones y demandadas no sólo de diversos actores externos, sino también de las facciones que integraban su trama política interna

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El objetivo de este trabajo es analizar el proceso de formulación y desarrollo de las políticas educativas durante el peronismo, teniendo en cuenta en qué medida intervinieron los actores estatales y no estatales. Nuestro ámbito de observación empírica, la provincia de Buenos Aires, nos permite dialogar con los trabajos efectuados desde un enfoque nacional. Nos interesa realizar un análisis histórico de la interacción entre estado y la sociedad, que tenga en cuenta no solo a los ejecutores sino a sus destinatarios. Se considera que los complejos procesos que rodearon la formulación de las políticas educativas durante esta etapa, se generaron en un contexto en que el gobierno provincial debió adecuar sus acciones a las presiones y demandadas no sólo de diversos actores externos, sino también de las facciones que integraban su trama política interna

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he global carbon cycle during the mid-Cretaceous (~125-88 million years ago, Ma) experienced numerous major perturbations linked to increased organic carbon burial under widespread, possibly basin-scale oxygen deficiency and episodes of euxinia (anoxic and H2S-containing). The largest of these episodes, the Cenomanian-Turonian boundary event (ca. 93.5 Ma), or oceanic anoxic event (OAE) 2, was marked by pervasive deposition of organic-rich, laminated black shales in deep waters and in some cases across continental shelves. This deposition is recorded in a pronounced positive carbon isotope excursion seen ubiquitously in carbonates and organic matter. Enrichments of redox-sensitive, often bioessential trace metals, including Fe and Mo, indicate major shifts in their biogeochemical cycles under reducing conditions that may be linked to changes in primary production. Iron enrichments and bulk Fe isotope compositions track the sources and sinks of Fe in the proto-North Atlantic at seven localities marked by diverse depositional conditions. Included are an ancestral mid-ocean ridge and euxinic, intermittently euxinic, and oxic settings across varying paleodepths throughout the basin. These data yield evidence for a reactive Fe shuttle that likely delivered Fe from the shallow shelf to the deep ocean basin, as well as (1) hydrothermal sources enhanced by accelerated seafloor spreading or emplacement of large igneous province(s) and (2) local-scale Fe remobilization within the sediment column. This study, the first to explore Fe cycling and enrichment patterns on an ocean scale using iron isotope data, demonstrates the complex processes operating on this scale that can mask simple source-sink relationships. The data imply that the proto-North Atlantic received elevated Fe inputs from several sources (e.g., hydrothermal, shuttle and detrital inputs) and that the redox state of the basin was not exclusively euxinic, suggesting previously unknown heterogeneity in depositional conditions and biogeochemical cycling within those settings during OAE-2.

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La estrategia i2010 de la UE tiene como objetivo garantizar el liderazgo europeo en materia de TIC y poner los beneficios de la Sociedad de la Información al servicio de la economía, la sociedad y la calidad de vida personal, teniendo presente que los éxitos de Europa hasta la fecha se han basado en favorecer la competencia leal en los mercados de las telecomunicaciones y crear un mercado sin fronteras para contenidos y medios de comunicación digitales. En esta línea, la Comisión Europea ha establecido que los distintos estados miembros deben contribuir activamente al desarrollo y uso seguro de los servicios telemáticos entre sus ciudadanos. Más concretamente, atribuye a las Administraciones Públicas, tanto a nivel nacional, regional como local, un papel dinamizador de la Sociedad de la Información que les obliga a ofrecer paulatinamente todos los actos administrativos a los ciudadanos a través de Internet. Como primer paso para el uso seguro de los servicios telemáticos que ofrecen las instituciones públicas se hace preciso dotar a los ciudadanos de una identidad digital que les permita identificarse ante un Proveedor de Servicio o ante otros ciudadanos de manera inequívoca. Por esta razón, la mayoría de países europeos – y otros en el resto del mundo – están promoviendo, sistemas fiables de gestión de identidad electrónica (eIDM), de tal manera que los ciudadanos, las empresas y departamentos gubernamentales (incluso en Estados miembros diferentes) pueden identificar y certificar sus operaciones con precisión, rapidez y sencillez. Sin embargo, la gestión de esta identidad por las Administraciones Públicas supone un importante desafío, acentuado cuando se hace necesaria la interoperabilidad entre Administraciones de diferentes países, puesto que personas y entidades tienen credenciales de identificación diferentes en función de su propio marco jurídico nacional. Consciente del problema, en la Unión Europea se han puesto en marcha una serie de proyectos con el objetivo de conseguir la interoperabilidad de los eIDMs entre las instituciones públicas de diferentes Estados miembros. A pesar de ello, las soluciones adoptadas hasta la fecha son insuficientes porque no prevén todos los posibles casos de interacción del usuario con las instituciones. En concreto, no tienen en cuenta un aspecto muy importante que se ofrece en los distintos sistemas jurídicos nacionales, a saber, la delegación de la identidad, mediante la cual un ciudadano puede autorizar a otro para que actúe en su nombre para acceder a determinados servicios prestados por las instituciones públicas. En esta tesis se realizan un conjunto de aportaciones que dan solución a distintos aspectos de los problemas planteados y que, de forma conjunta, permiten la interoperabilidad y la delegación de identidad en determinados Sistemas de Gestión de Identidad aplicados al entorno de las Administraciones Públicas. En el caso de la delegación, se ha definido un sistema de delegación dinámica de identidad entre dos entidades genéricas que permite solucionar el problema del acceso delegado a los servicios telemáticos ofrecidos por las Administraciones Públicas. La solución propuesta se basa en la generación de un token de delegación, constituido a partir de un Certificado Proxy, que permite a la entidad que delega establecer la delegación de identidad en otra entidad en base a un subconjunto de sus atributos como delegador, estableciendo además, en el propio token de delegación, restricciones en el conjunto de servicios accesibles a la entidad delegada y el tiempo de validez de la delegación. Adicionalmente, se presentan los mecanismos necesarios tanto para poder revocar un token de delegación como para comprobar sin un token de delegación ha sido o no revocado. Para ello se propone una solución para la identificación unívoca de tokens de delegación y la creación de una nueva entidad denominada Autoridad de Revocación de Tokens de Delegación. Entre las características del sistema de delegación propuesto destaca el que es lo suficientemente seguro como para ser utilizado en el entorno de la Administración Pública, que no requiere el uso de mecanismos off‐line para la generación de la delegación y que se puede realizar la delegación de forma instantánea y sin la necesidad de trámites complejos o la participación de un elevado número de entidades. Adicionalmente, el token de delegación propuesto es perfectamente integrable en las infraestructura de clave pública actual lo que hace que, dado que gran parte de las Administraciones Públicas europeas basan sus sistemas de identidad digital en el uso de la PKI y certificados de identidad X.509, la solución pueda ser puesta en marcha en un entorno real sin necesidad de grandes cambios o modificaciones de comportamiento. En lo referente a la interoperabilidad, se realiza un análisis exhaustivo y la correspondiente evaluación de las principales propuestas de Sistemas de Gestión de Identidad orientados a conseguir la interoperabilidad realizadas hasta la fecha en el marco de la Unión Europea y se propone, a alto nivel, una arquitectura de interoperabilidad para la gestión de identidad en las Administraciones Públicas. Dicha arquitectura es lo suficientemente genérica como para poder ser aplicada tanto en el entorno pan‐Europeo como en los entornos nacionales, autonómicos y locales, de tal forma que la interoperabilidad en la gestión de la identidad esté garantizada en todos los niveles de la Administración Pública. Por último, mediante la integración de la solución de delegación dinámica de identidad y la arquitectura de interoperabilidad propuestas se presenta una solución al problema de la delegación en un escenario pan‐Europeo de gestión de identidad, dando lugar a una arquitectura global de interoperabilidad pan‐Europea con soporte a la delegación de identidad. SUMMARY The i2010 European Union Plan aims to ensure European leadership in ICT and to promote the positive contribution that information and communication technologies can make to the economic, social and personal quality of life, bearing in mind that, to date, success in Europe has been based on promoting fair competition in telecommunications markets and on creating a borderless market for contents and digital media. In this line, the European Commission has established that the different member states should contribute actively to the development and secure use of telematic services among their citizens. More specifically, it is attributed to national, regional and local Public Administrations to have a supportive role of the Information Society, requiring them to gradually provide the citizens with Internet‐based access to all administrative procedures acts. As a first step for the secure use of telematic services offered by public institutions, it is necessary to provide the citizens with a digital identity to enable them to identify themselves unequivocally to a Service Provider or to other citizens. For this reason, most European countries ‐ and others in the rest of the world ‐ are promoting reliable systems for managing electronic identity (eIDM), so that citizens, businesses and government departments (even in different Member States) can identify and certify their operations with precision, speed and simplicity. However, the identity management by Public Administrations is a major challenge that becomes more difficult when interoperability between administrations of different countries is needed, due to the fact that individuals and entities have different identification credentials according to their own national legal framework. Aware of the problem, the European Union has launched a series of projects with the aim of achieving interoperability of eIDMs between public institutions of different Member States. However, the solutions adopted to date are insufficient because they do not foresee all possible cases of user interaction with the institutions. In particular, solutions do not take into account a very important aspect that is offered in different national legal systems, namely, the delegation of identity, by which a citizen can authorize another to act on his/her behalf to access certain services provided by public institutions. In this thesis a collection of contributions that provide solution to different aspects of the aforementioned problems are carried out. The solutions, in global, enable interoperability and identity delegation in some of the Identity Management Systems applied to Public Administration environment. In the case of delegation, a dynamic identity delegation system between generic entities is defined. This system makes it possible to solve the problem of delegated access to telematic services offered by Public Administrations. The proposed solution is based on the generation of a piece of information called delegation token. This delegation token, derived from a Proxy Certificate, allows the establishment of identity delegation by an entity that delegates (delegator) in other entity (delegatee) making use of a subset of delegator attributes. It also establishes restrictions on services that can be used by the delegated entity and the expiry date of delegation. In addition to this, the mechanisms necessary to revoke and check the revocation status of a delegation token are presented. To do this, a solution to univocally identify delegation tokens and the creation of a completely new entity, called Token Delegation Revocation Authority, are proposed. The most remarkable characteristics of the proposed delegation system are its security, enough for it to be used in the Public Administration environment, the fact that it does not require off‐line processes in order to generate the delegation, and the possibility of performing the delegation instantaneously and without neither complex processes nor the intervention of a large number of entities. The proposed delegation token can be completely incorporated into current Public Key Infrastructure (PKI). Thus, since most of the European Public Administrations base their digital identity systems on PKI and X.509 identity certificates, the solution can be adopted in a real environment without great changes or performance modifications. Regarding interoperability, an exhaustive analysis and evaluation of most significant proposals on Identity Management Systems that aim to achieve interoperability carried out in the European Union framework until now are performed. A high level identity management interoperability architecture for Public Administrations is also proposed. This architecture is sufficiently generic to be applied to both pan‐European environment and national, regional or local environments, thus interoperability in identity management at all Public Administration levels is guaranteed. Finally, through the integration of the proposed dynamic identity delegation solution and the high level interoperability architecture, a solution to the problem of identity delegation in a pan‐European identity management environment is suggested, leading to a pan‐European global interoperability architecture with identity delegation support.

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The relevance of renewable energy has grown significantly in our global society. Important efforts are oriented to sustain it. Renewable energy depends on different technical, financial environmental and social complex processes. From the point of view of industrial construction sector this research evaluates some of the current trends in energy generation and use in Venezuela as well as environmental consequences and risks that derive from these. Additionally, authors highlight the importance of infrastructure as key issue to sustain renewable energy generation and use. The study present references of some energy renewable projects in process in Venezuela and the main problems that constrain their performance. Conclusions evidence the complex nature of industrial construction and suggest the need to improve industrial construction competitivenes as a strategy oriented to enhance renewable energy offer in the country. Additionally it is proposed to all stakeholders to work toghether to correct the conditions that currently limit industrial construction development. This is part of ongoing research.

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The recognition of the relevance of energy, especially of the renewable energies generated by the sun, water, wind, tides, modern biomass or thermal is growing significantly in the global society based on the possibility it has to improve societies′ quality of life, to support poverty reduction and sustainable development. Renewable energy, and mainly the energy generated by large hydropower generation projects that supply most of the renewable energy consumed by developing countries, requires many technical, legal, financial and social complex processes sustained by innovations and valuable knowledge. Besides these efforts, renewable energy requires a solid infrastructure to generate and distribute the energy resources needed to solve the basic needs of society. This demands a proper construction performance to deliver the energy projects planned according to specifications and respecting environmental and social concerns, which implies the observance of sustainable construction guidelines. But construction projects are complex and demanding and frequently face time and cost overruns that may cause negative impacts on the initial planning and thus on society. The renewable energy issue and the large renewable energy power generation and distribution projects are particularly significant for developing countries and for Latin America in particular, as this region concentrates an important hydropower potential and installed capacity. Using as references the performance of Venezuelan large hydropower generation projects and the Guri dam construction, this research evaluates the tight relationship existing between sustainable construction and knowledge management and their impact to achieve sustainability goals. The knowledge management processes are proposed as a basic strategy to allow learning from successes and failures obtained in previous projects and transform the enhancement opportunites into actions to improve the performance of the renewable energy power generation and distribution projects.

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As it is known, there are five types of neurons in the mammalian retinal layer allowing the detection of several important characteristics of the visual image impinging onto the visual system, namely, photoreceptors, horizontal cells, amacrine, bipolar and ganglion cells. And it is a well known fact too, that the amacrine neuron architecture allows a first detection for objects motion, being the most important retinal cell to this function. We have already studied and simulated the Dowling retina model and we have verified that many complex processes in visual detection is performed with the basis of the amacrine cell synaptic connections. This work will show how this structure may be employed for motion detection

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Durante los últimos años, el imparable crecimiento de fuentes de datos biomédicas, propiciado por el desarrollo de técnicas de generación de datos masivos (principalmente en el campo de la genómica) y la expansión de tecnologías para la comunicación y compartición de información ha propiciado que la investigación biomédica haya pasado a basarse de forma casi exclusiva en el análisis distribuido de información y en la búsqueda de relaciones entre diferentes fuentes de datos. Esto resulta una tarea compleja debido a la heterogeneidad entre las fuentes de datos empleadas (ya sea por el uso de diferentes formatos, tecnologías, o modelizaciones de dominios). Existen trabajos que tienen como objetivo la homogeneización de estas con el fin de conseguir que la información se muestre de forma integrada, como si fuera una única base de datos. Sin embargo no existe ningún trabajo que automatice de forma completa este proceso de integración semántica. Existen dos enfoques principales para dar solución al problema de integración de fuentes heterogéneas de datos: Centralizado y Distribuido. Ambos enfoques requieren de una traducción de datos de un modelo a otro. Para realizar esta tarea se emplean formalizaciones de las relaciones semánticas entre los modelos subyacentes y el modelo central. Estas formalizaciones se denominan comúnmente anotaciones. Las anotaciones de bases de datos, en el contexto de la integración semántica de la información, consisten en definir relaciones entre términos de igual significado, para posibilitar la traducción automática de la información. Dependiendo del problema en el que se esté trabajando, estas relaciones serán entre conceptos individuales o entre conjuntos enteros de conceptos (vistas). El trabajo aquí expuesto se centra en estas últimas. El proyecto europeo p-medicine (FP7-ICT-2009-270089) se basa en el enfoque centralizado y hace uso de anotaciones basadas en vistas y cuyas bases de datos están modeladas en RDF. Los datos extraídos de las diferentes fuentes son traducidos e integrados en un Data Warehouse. Dentro de la plataforma de p-medicine, el Grupo de Informática Biomédica (GIB) de la Universidad Politécnica de Madrid, en el cuál realicé mi trabajo, proporciona una herramienta para la generación de las necesarias anotaciones de las bases de datos RDF. Esta herramienta, denominada Ontology Annotator ofrece la posibilidad de generar de manera manual anotaciones basadas en vistas. Sin embargo, aunque esta herramienta muestra las fuentes de datos a anotar de manera gráfica, la gran mayoría de usuarios encuentran difícil el manejo de la herramienta , y pierden demasiado tiempo en el proceso de anotación. Es por ello que surge la necesidad de desarrollar una herramienta más avanzada, que sea capaz de asistir al usuario en el proceso de anotar bases de datos en p-medicine. El objetivo es automatizar los procesos más complejos de la anotación y presentar de forma natural y entendible la información relativa a las anotaciones de bases de datos RDF. Esta herramienta ha sido denominada Ontology Annotator Assistant, y el trabajo aquí expuesto describe el proceso de diseño y desarrollo, así como algunos algoritmos innovadores que han sido creados por el autor del trabajo para su correcto funcionamiento. Esta herramienta ofrece funcionalidades no existentes previamente en ninguna otra herramienta del área de la anotación automática e integración semántica de bases de datos. ---ABSTRACT---Over the last years, the unstoppable growth of biomedical data sources, mainly thanks to the development of massive data generation techniques (specially in the genomics field) and the rise of the communication and information sharing technologies, lead to the fact that biomedical research has come to rely almost exclusively on the analysis of distributed information and in finding relationships between different data sources. This is a complex task due to the heterogeneity of the sources used (either by the use of different formats, technologies or domain modeling). There are some research proyects that aim homogenization of these sources in order to retrieve information in an integrated way, as if it were a single database. However there is still now work to automate completely this process of semantic integration. There are two main approaches with the purpouse of integrating heterogeneous data sources: Centralized and Distributed. Both approches involve making translation from one model to another. To perform this task there is a need of using formalization of the semantic relationships between the underlying models and the main model. These formalizations are also calles annotations. In the context of semantic integration of the information, data base annotations consist on defining relations between concepts or words with the same meaning, so the automatic translation can be performed. Depending on the task, the ralationships can be between individuals or between whole sets of concepts (views). This paper focuses on the latter. The European project p-medicine (FP7-ICT-2009-270089) is based on the centralized approach. It uses view based annotations and RDF modeled databases. The data retireved from different data sources is translated and joined into a Data Warehouse. Within the p-medicine platform, the Biomedical Informatics Group (GIB) of the Polytechnic University of Madrid, in which I worked, provides a software to create annotations for the RDF sources. This tool, called Ontology Annotator, is used to create annotations manually. However, although Ontology Annotator displays the data sources graphically, most of the users find it difficult to use this software, thus they spend too much time to complete the task. For this reason there is a need to develop a more advanced tool, which would be able to help the user in the task of annotating p-medicine databases. The aim is automating the most complex processes of the annotation and display the information clearly and easy understanding. This software is called Ontology Annotater Assistant and this book describes the process of design and development of it. as well as some innovative algorithms that were designed by the author of the work. This tool provides features that no other software in the field of automatic annotation can provide.

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Actualmente en nuestro planeta producimos 1.300 millones de toneladas de residuos urbanos al año. Si los extendemos sobre la superficie de un cuadrado de lado 100 m (una hectárea) alcanzarían una altura de 146 km. ¿Cuál es el origen de nuestros residuos? ¿A dónde va esta basura? ¿Cómo nos afecta? ¿Tiene alguna utilidad? Se trata de un problema antiguo que, en los últimos tiempos, ha adquirido una nueva dimensión por el tipo y la cantidad de residuos generados. Las primeras preocupaciones de la ciudad por ordenar estos problemas dieron lugar al establecimiento de espacios o lugares específicos para la acumulación de los residuos urbanos: los vertederos. Los desechos hoy se generan más rápidamente que los medios disponibles para reciclarlos o tratarlos. Los vertederos de residuos urbanos son y seguirán siendo, a corto y medio plazo, soluciones válidas por ser un método de gestión relativamente barato, sobre todo en los países en vías de desarrollo. Como consecuencia y necesidad de lo anterior, se plantea demostrar que la recuperación y la transformación de estos vertederos de residuos urbanos (lugares del deterioro), una vez abandonados, es posible y que además pueden dar lugar a nuevos espacios públicos estratégicos de la ciudad contemporánea. Son espacios de oportunidad, vacíos monumentales producto de una reactivación arquitectónica y paisajística realizada a partir de complejos procesos de ingeniería medioambiental. Pero las soluciones aplicadas a los vertederos de residuos urbanos desde mediados del siglo XX se han realizado exclusivamente desde la ingeniería para tratar de resolver cuestiones técnicas, un modelo agotado que ya no puede gestionar la magnitud que este problema ha alcanzado, haciéndose necesaria e inevitable la participación de la arquitectura para abrir nuevas líneas de investigación y de acción. En estos primeros compases del siglo XXI existe una “nueva” preocupación, un “nuevo” interés en los paradigmas de lo ecológico y de la sostenibilidad, también un interés filosófico (que igualmente otorga un nuevo valor al residuo como recurso), que dirigen su mirada hacia un concepto de paisaje abierto y diferente a modelos anteriores más estáticos, recuperando como punto de partida el ideal pintoresco. El landscape urbanism se consolida como una disciplina capaz de dar respuesta a lo natural y artificial simultáneamente, que sustituye a las herramientas tradicionales de la arquitectura para solucionar los problemas de la ciudad contemporánea, incorporando las infraestructuras de gran escala, como un vertedero de residuos urbanos, y los paisajes públicos que generan como el verdadero mecanismo de organización del urbanismo de hoy. No se trata solo de un modelo formal sino, lo que es más importante: de un modelo de procesos. Esta nueva preocupación permite abordar la cuestión del paisaje de manera amplia, sin restricciones, con un alto grado de flexibilidad en las nuevas propuestas que surgen como consecuencia de estos conceptos, si bien los esfuerzos, hasta la fecha, parecen haberse dirigido más hacia el fenómeno de lo estético, quedando todavía por explorar las consecuencias políticas, sociales, económicas y energéticas derivadas de los residuos. También las arquitectónicas. El proyecto del landscape urbanism se ocupa de la superficie horizontal, del plano del suelo. Desde siempre, la preparación de este plano para desarrollar cualquier actividad humana ha sido un gesto fundacional, un gesto propio necesario de toda arquitectura, que además ahora debe considerarlo como un medio o soporte biológicamente activo. En términos contemporáneos, el interés disciplinar radica en la continuidad y en la accesibilidad del suelo, diluyendo los límites; en que funcione a largo plazo, que se anticipe al cambio, a través de la flexibilidad y de la capacidad de negociación, y que sea público. La recuperación de un vertedero de residuos urbanos ofrece todas estas condiciones. Un breve recorrido por la historia revela los primeros ejemplos aislados de recuperación de estos lugares del deterioro, que han pasado por distintas fases en función de la cantidad y el tipo de los desechos producidos, evolucionando gracias a la tecnología y a una nueva mirada sobre el paisaje, hasta desarrollar una verdadera conciencia de lo ecológico (nacimiento de una ideología). El Monte Testaccio en Roma (siglos I-III d.C.) constituye un caso paradigmático y ejemplar de vertedero planificado a priori no solo como lugar en el que depositar los residuos, sino como lugar que será recuperado posteriormente y devuelto a la ciudad en forma de espacio público. Una topografía de desechos generada por acumulación, organizada y planificada durante tres siglos, que nos hace reflexionar sobre los temas de producción, consumo y proyecto arquitectónico. El Monte Testaccio revela una fuente de inspiración, un arquetipo de gestión sostenible de los recursos y del territorio. A través de la experiencia en la recuperación y transformación en espacios públicos de casos contemporáneos, como el antiguo vertedero de Valdemingómez en Madrid o el de El Garraf en Barcelona, se han analizado las técnicas y las soluciones empleadas para establecer nuevas herramientas de proyecto planteadas en clave de futuro, que revelan la importancia de los procesos frente a la forma, en los cuales intervienen muchos factores (tanto naturales como artificiales), entre ellos la vida y el tiempo de la materia viva acumulada. Son lugares para nuevas oportunidades y ejemplos de una nueva relación con la naturaleza. La reactivación de los vertederos de residuos, a través del proyecto, nos propone una nueva topografía construida en el tiempo, el suelo como soporte, como punto de encuentro de la naturaleza y los sistemas tecnológicos de la ciudad que posibilitan nuevos modos de vida y nuevas actividades. Los vertederos de residuos son inmensas topografías naturales surgidas de procesos artificiales, atalayas desde las que divisar un nuevo horizonte, un nuevo mundo, un nuevo futuro donde sea posible lograr la reversibilidad de nuestros actos del deterioro. Pero la voluntad de estas recuperaciones y transformaciones no consiste exclusivamente en su reintegración al paisaje, sino que han servido como muestra de las nuevas actitudes que la sociedad ha de emprender en relación a los temas medio ambientales. ABSTRACT Here on our planet we currently produce 1.3 billion tonnes of urban waste per year. If we were to spread this over a surface of 100m2 (one hectare), it would reach a height of 146km. What is the origin of this waste? Where does our refuse go? How does it affect us? Does it have any uses? We are dealing with an old problem which, in recent times, has taken on a new dimension due to the type of waste and the amount generated. Cities’ first concerns in resolving these problems gave rise to the establishment of areas or specific places for the accumulation of urban waste: landfills. These days, waste is generated more quickly than the available resources can recycle or process it. Urban waste landfills are and will continue to be, in the short and mid-term, valid solutions, given that they constitute a relatively cheap method for waste management, especially in developing countries. Consequently and necessarily, we plan to demonstrate that it is possible to recover and transform these urban waste landfills (areas of deterioration) once they have been abandoned and that they can give rise to new strategic public areas in contemporary cities. They are areas of opportunity, monumental vacancies produced by an architectural reactivation of the landscape, which is achieved using complex processes of environmental engineering. But the solutions applied to urban waste landfills throughout the 20th century have used engineering exclusively in the attempt to resolve the technical aspects. This is a worn-out model which can no longer handle the magnitude which the problem has attained and therefore, there is an inevitable need for the participation of architecture, which can open new lines of research and action. In these first steps into the 21st century, there is a “new” concern, a “new” interest in the paradigms of environmentalism and sustainability. There is also a philosophical interest (which assigns the new value of ‘resource’ to waste) and all is aimed towards the concept of an open landscape, unlike the previous, more static models, and the intention is to recover picturesque ideals as the starting point. Landscape urbanism has been established as a discipline capable of simultaneously responding to the natural and the artificial, replacing the traditional tools of architecture in order to resolve contemporary cities’ problems. It incorporates large scale infrastructures, such as urban waste landfills, and public landscapes which are generated as the true organisational mechanism of modern day urbanism. It is not merely a formal model, it is more important than that: it is a model of processes. This new concern allows us to address the matter of landscape in a broad way, without restrictions, and with a great degree of flexibility in the new proposals which come about as a consequence of these concepts. However, efforts to date seem to have been more directed at aesthetic aspects and we have yet to explore the political, social, economic and energetic consequences derived from waste – nor have we delved into the architectural consequences. The landscape urbanism project is involved with the horizontal surface, the ground plane. Traditionally, the preparation of this plane for the development of any human activity has been a foundational act, a necessary act of all architecture, but now this plane must be considered as a biologically active medium or support. In contemporary terms, the discipline’s interest lies in the continuity and accessibility of the land, diffusing the limits; in long term functionality; in the anticipation of change, via flexibility and the ability to negotiate; and in it being a public space. The recovery of an urban waste landfill offers all of these conditions. A brief look through history reveals the first isolated examples of recovery of these spaces of deterioration. They have gone through various phases based on the quantity and type of waste produced, they have evolved thanks to technology and a new outlook on the landscape, and a real environmental awareness has been developed (the birth of an ideology). Monte Testaccio in Rome (1st to 3rd Century AD) constitutes a paradigmatic and exemplary case of a landfill that was planned a priori not only as a place to deposit waste but also as a place that would be subsequently recovered and given back to the city in the form of a public space. This spoil mound, generated by organised and planned accumulation over three centuries, makes us reflect on the themes of production, consumption and architectural planning. Monte Testaccio reveals a source of inspiration, an archetype of the sustainable management of resources and land. Using our experience of contemporary cases of land recovery and its transformation into public spaces, such as the former Valdemingómez landfill in Madrid or the Garraf in Barcelona, we analysed the techniques and solutions used in order to establish new project tools. These are proposed with an eye on the future, seeing as they reveal the importance of the processes over the form and involve many factors (both natural and artificial), including the life and age of the accumulated living matter. They are places for new opportunities and examples of our new relationship with nature. The reactivation of landfills, via this project, is a proposal for a new topography built within time, using the ground as the support, as the meeting point between nature and the technological systems of the city which make it possible for new ways of life and new activities to come about. Landfills are immense natural topographical areas produced by artificial processes, watchtowers from which to discern a new horizon, a new world, a new future in which it will be possible to reverse our acts of deterioration. But the intention behind these recoveries and transformations does not only hope for landscape reintegration but it also hopes that they will also serve as a sign of the new attitudes that must be adopted by society with regard to environmental matters.