633 resultados para Cambrian explosion
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RESUMO - Visa-se explicitar a origem, a razão de ser, a natureza e o que se perspectiva da relação entre a Epidemiologia e a Saúde Pública, através de uma leitura histórica. As duas entidades foram-se definindo e fazendo sentido em conjunto, com sucessos e, também, muita polémica, desde há milénios e até meados do século XIX. Nesta época, uma combinação de circunstâncias proporcionou-lhes uma explosão de crescimento e de definição, de par com várias outras áreas disciplinares. Desde o antigo relato bíblico de como boa alimentação explica o bom estado de saúde, até à valorização científica das condicionantes sociais e económicas da saúde por Marmot e Rose, passando por «miasmas» causando doença e pela deslocação do conceito de risco individual de saúde para o de risco populacional — com as implicações inerentes a essa importante inovação —, este percurso permite identificar as fundações de tão notável simbiose, explicar o estado presente, vê-la evoluir e achar nela o significado do património hoje disponível, e o que ele promete. Algumas discrepâncias quanto à designação dos seus métodos, bem como a contínua discussão quanto à sua verdadeira natureza e orientação futura, atestam a juventude da Epidemiologia como disciplina científica. Entretanto, a Saúde Pública esforça-se por manter a sua essência integradora, à medida que outras disciplinas contribuem mais para que concretize os seus objectivos; é desafiada pela exposição das populações, em larga escala, a factores de doença, por vezes de intensidade mínima, e pelo surgimento de novas doenças ou a ampliação do volume de outras na população, muitas vezes não respeitando fronteiras. A história dessa simbiose mostra bem que conhecer o modo como uma doença se origina permite controlá-la na população, ou mesmo evitá-la, e que é grande o número de problemas que, em sinergia, as duas disciplinas podem clarificar e resolver. Assim, a Epidemiologia oferece à Saúde Pública explicações (olhos, inteligência e linguagem) para os problemas de saúde das populações — o que permite à segunda saber sobre o quê agir —, cenários de possível evolução dos problemas — o que permite aos decisores optarem em função de diferentes pressupostos, sobre como agir — e capacidade de juízo sobre os resultados das acções empreendidas, em simultâneo com a elevação do nível de consciência, de compreensão e de intervenção quanto ao que se está a passar, tanto pelos profissionais, como pela população — transferência do conhecimento. Facilmente se antecipa que a relação entre as duas disciplinas irá evoluir para maior complexidade e, também, solicitação e exigência da Saúde Pública sobre a Epidemiologia, que terá que corresponder em utilidade. E esta, continuando a subespecializar-se e a sofisticar-se tanto nos métodos, como nos enfoques sobre categorias específicas de factores, precisará de progredir muito na gestão da sua consistência enquanto corpo de conhecimento integrado e com peculiaridades metodológicas, à semelhança da Saúde Pública.O modo como evoluirá a relação entre ambas depende ainda da evolução dos próprios problemas, conceitos, teorias e soluções relacionados com a saúde das populações, e ainda do desenvolvimento das demais disciplinas chamadas à integração por ambas, para enfrentarem esses desafios. Nomeadamente, a Epidemiologia terá que gerir com perícia dificuldades já identificadas, como: incorporar métodos qualitativos de investigação na sua fortíssima tradição e cultura quantitativa; operacionalizar satisfatoriamente o conceito de «risco atribuível na população», ao serviço da definição de prioridades de acção dirigida às necessidades de saúde; aperfeiçoar modelos de interpretação causal que respeitem a multicausalidade; aproveitar as técnicas estatísticas de análise multivariada, sem se perder na abstracção dos seus modelos; desenvolver a investigação nas dimensões positivas de saúde, além da doença, para contribuir melhor para a realização da Saúde Pública, sua principal cliente e fornecedora de oportunidades.--------------------------ABSTRACT - The aim of the author is to explicit the origin, the rationale, the nature and the prospects of the relationship between Epidemiology and Public health, through an historic approach. The two entities have been defining and making sense together, by achieving successes, but also with much controversy, since millennia ago, until mid XIX century. A combination of circumstances provided them the opportunity for an explosion of growth and definition, then, alongside several other disciplines. From the ancient biblical report on how good food explains good health, up to the scientific appreciation of both social and economical constraints to health by Marmot and Rose, passing through «miasma» causing disease and through displacing from individual health risk to population risk — with the inherent implications of that important innovation —, this route allows the identification of the foundations of such remarkable symbiosis, the explanation of current status, to see its evolution and find in it the meaning of today’s heritage and what it promises. Some discrepancies on the name of its methods, as well as the continuing discussion about its true nature and future orientation, attest Epidemiology’s youth as a scientific discipline. Meanwhile, Public Health strives to keep its integrating essence, while other disciplines increasingly contribute so that it achieves its objectives; it is challenged by large scale population exposure to disease factors, sometimes with a minimum intensity, and by new diseases emerging in the population or by old ones getting amplified, often not respecting regions boundaries. The history of such a symbiosis shows that knowing the way a disease is generated allows to control it in the population, or even to avoid it, and that the number of problems that the two disciplines are able to clarify and solve together in synergy is considerable. Therefore, Epidemiology offers Public Health explanations (eyes, intelligence and language) for populations’s health problems — allowing that the latter knows on what to act —, scenarios on how problems may tend to evolve — allowing decision-makers to make their choices as a function of different assumptions, on how to act — and judgement capabilities on the results of already undertaken actions, accompanied by the raising of conscience level, understanding and intervention of what is going on by both professionals and the population – knowledge transfer. It is easy to anticipate that the relationship between both disciplines will develop towards increasing complexity and demand from Public Health to Epidemiology, and that this one will have to correspond in usefulness. And the latter, while continuing its subspecialisation and sophistication either in its methods, or in its approaches to specific factor categories, will need to progress in managing its consistency as an integrated body of knowledge having methodological peculiarities, similarly to Public Health. Further, the way the relationship between both will evolve depends on the evolution of the problems themselves, of the concepts, theories and solutions related to the health of populations, and on the development of remaining disciplines called to integration by both, in other to face those problems. Namely, Epidemiology will have to manage with expertise some already known difficulties, as: the inclusion of qualitative research methods in its very strong quantitative tradition and culture; to grant satisfactory operation to the «population attributable risk» concept, in support to the definition of action priorities envisaging health needs; to improve causal interpretation models that comply with multicausality; to take advantage of multivariate statistical techniques, without get
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Poster presented in The 28th GI/ITG International Conference on Architecture of Computing Systems (ARCS 2015). 24 to 26, Mar, 2015. Porto, Portugal.
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Presented at SEMINAR "ACTION TEMPS RÉEL:INFRASTRUCTURES ET SERVICES SYSTÉMES". 10, Apr, 2015. Brussels, Belgium.
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The colors that are seen in dermoscopy depend on the anatomic level of the skin at which the chromophores are seen. Blue color can be found in a variety of melanocytic and nonmelanocytic lesions. An 89-year-old man presented with a 3-year history of a slow-growing, hyperpigmented patch located on the distal third of the right arm. Dermoscopy showed an atypical network, irregularly distributed globules, pigmented internal streaks and a milky-red area. Based on these findings a diagnosis of slow-growing malignant melanoma was made. Simultaneously, a well-defined blue papule was seen on the proximal third of the same arm. Dermoscopy disclosed a homogeneous blue pattern. After clinical and dermoscopic correlation our differential diagnosis for this blue lesion included cutaneous melanoma metastasis, blue nevus and foreign body reaction. The patient recalled its onset 75 years ago after a grenade explosion. We also discuss the blue lesion appearance under reflectance confocal microscopy and high-definition optical coherence tomography. Histopathological examination after excision of the hyperpigmented patch and blue papule revealed a melanoma in situ and a foreign body reaction, respectively. The diagnostic evaluation of a blue lesion should always rely on the integration of all data, especially clinical and dermoscopic features. Other non-invasive techniques, like reflectance confocal microscopy and high-definition optical coherence tomography can also be important aids for its differential diagnosis.
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Dissertação para Obtenção do Grau de Mestre em Engenharia e Gestão Industrial
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Ontologies formalized by means of Description Logics (DLs) and rules in the form of Logic Programs (LPs) are two prominent formalisms in the field of Knowledge Representation and Reasoning. While DLs adhere to the OpenWorld Assumption and are suited for taxonomic reasoning, LPs implement reasoning under the Closed World Assumption, so that default knowledge can be expressed. However, for many applications it is useful to have a means that allows reasoning over an open domain and expressing rules with exceptions at the same time. Hybrid MKNF knowledge bases make such a means available by formalizing DLs and LPs in a common logic, the Logic of Minimal Knowledge and Negation as Failure (MKNF). Since rules and ontologies are used in open environments such as the Semantic Web, inconsistencies cannot always be avoided. This poses a problem due to the Principle of Explosion, which holds in classical logics. Paraconsistent Logics offer a solution to this issue by assigning meaningful models even to contradictory sets of formulas. Consequently, paraconsistent semantics for DLs and LPs have been investigated intensively. Our goal is to apply the paraconsistent approach to the combination of DLs and LPs in hybrid MKNF knowledge bases. In this thesis, a new six-valued semantics for hybrid MKNF knowledge bases is introduced, extending the three-valued approach by Knorr et al., which is based on the wellfounded semantics for logic programs. Additionally, a procedural way of computing paraconsistent well-founded models for hybrid MKNF knowledge bases by means of an alternating fixpoint construction is presented and it is proven that the algorithm is sound and complete w.r.t. the model-theoretic characterization of the semantics. Moreover, it is shown that the new semantics is faithful w.r.t. well-studied paraconsistent semantics for DLs and LPs, respectively, and maintains the efficiency of the approach it extends.
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Digital Businesses have become a major driver for economic growth and have seen an explosion of new startups. At the same time, it also includes mature enterprises that have become global giants in a relatively short period of time. Digital Businesses have unique characteristics that make the running and management of a Digital Business much different from traditional offline businesses. Digital businesses respond to online users who are highly interconnected and networked. This enables a rapid flow of word of mouth, at a pace far greater than ever envisioned when dealing with traditional products and services. The relatively low cost of incremental user addition has led to a variety of innovation in pricing of digital products, including various forms of free and freemium pricing models. This thesis explores the unique characteristics and complexities of Digital Businesses and its implications on the design of Digital Business Models and Revenue Models. The thesis proposes an Agent Based Modeling Framework that can be used to develop Simulation Models that simulate the complex dynamics of Digital Businesses and the user interactions between users of a digital product. Such Simulation models can be used for a variety of purposes such as simple forecasting, analysing the impact of market disturbances, analysing the impact of changes in pricing models and optimising the pricing for maximum revenue generation or a balance between growth in usage and revenue generation. These models can be developed for a mature enterprise with a large historical record of user growth rate as well as for early stage enterprises without much historical data. Through three case studies, the thesis demonstrates the applicability of the Framework and its potential applications.
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Doctoral Thesis Civil Engineering
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The MAP-i Doctoral Program of the Universities of Minho, Aveiro and Porto.
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Rockburst is characterized by a violent explosion of a block causing a sudden rupture in the rock and is quite common in deep tunnels. It is critical to understand the phenomenon of rockburst, focusing on the patterns of occurrence so these events can be avoided and/or managed saving costs and possibly lives. The failure mechanism of rockburst needs to be better understood. Laboratory experiments are undergoing at the Laboratory for Geomechanics and Deep Underground Engineering (SKLGDUE) of Beijing and the system is described. A large number of rockburst tests were performed and their information collected, stored in a database and analyzed. Data Mining (DM) techniques were applied to the database in order to develop predictive models for the rockburst maximum stress (σRB) and rockburst risk index (IRB) that need the results of such tests to be determined. With the developed models it is possible to predict these parameters with high accuracy levels using data from the rock mass and specific project.
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Tese de Doutoramento Engenharia Têxtil
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La programación concurrente es una tarea difícil aún para los más experimentados programadores. Las investigaciones en concurrencia han dado como resultado una gran cantidad de mecanismos y herramientas para resolver problemas de condiciones de carrera de datos y deadlocks, problemas que surgen por el mal uso de los mecanismos de sincronización. La verificación de propiedades interesantes de programas concurrentes presenta dificultades extras a los programas secuenciales debido al no-determinismo de su ejecución, lo cual resulta en una explosión en el número de posibles estados de programa, haciendo casi imposible un tratamiento manual o aún con la ayuda de computadoras. Algunos enfoques se basan en la creación de lenguajes de programación con construcciones con un alto nivel de abstración para expresar concurrencia y sincronización. Otros enfoques tratan de desarrollar técnicas y métodos de razonamiento para demostrar propiedades, algunos usan demostradores de teoremas generales, model-checking o algortimos específicos sobre un determinado sistema de tipos. Los enfoques basados en análisis estático liviano utilizan técnicas como interpretación abstracta para detectar ciertos tipos de errores, de una manera conservativa. Estas técnicas generalmente escalan lo suficiente para aplicarse en grandes proyectos de software pero los tipos de errores que pueden detectar es limitada. Algunas propiedades interesantes están relacionadas a condiciones de carrera y deadlocks, mientras que otros están interesados en problemas relacionados con la seguridad de los sistemas, como confidencialidad e integridad de datos. Los principales objetivos de esta propuesta es identificar algunas propiedades de interés a verificar en sistemas concurrentes y desarrollar técnicas y herramientas para realizar la verificación en forma automática. Para lograr estos objetivos, se pondrá énfasis en el estudio y desarrollo de sistemas de tipos como tipos dependientes, sistema de tipos y efectos, y tipos de efectos sensibles al flujo de datos y control. Estos sistemas de tipos se aplicarán a algunos modelos de programación concurrente como por ejemplo, en Simple Concurrent Object-Oriented Programming (SCOOP) y Java. Además se abordarán propiedades de seguridad usando sistemas de tipos específicos. Concurrent programming has remained a dificult task even for very experienced programmers. Concurrency research has provided a rich set of tools and mechanisms for dealing with data races and deadlocks that arise of incorrect use of synchronization. Verification of most interesting properties of concurrent programs is a very dificult task due to intrinsic non-deterministic nature of concurrency, resulting in a state explosion which make it almost imposible to be manually treat and it is a serious challenge to do that even with help of computers. Some approaches attempts create programming languages with higher levels of abstraction for expressing concurrency and synchronization. Other approaches try to develop reasoning methods to prove properties, either using general theorem provers, model-checking or specific algorithms on some type systems. The light-weight static analysis approach apply techniques like abstract interpretation to find certain kind of bugs in a conservative way. This techniques scale well to be applied in large software projects but the kind of bugs they may find are limited. Some interesting properties are related to data races and deadlocks, while others are interested in some security problems like confidentiality and integrity of data. The main goals of this proposal is to identify some interesting properties to verify in concurrent systems and develop techniques and tools to do full automatic verification. The main approach will be the application of type systems, as dependent types, type and effect systems, and flow-efect types. Those type systems will be applied to some models for concurrent programming as Simple Concurrent Object-Oriented Programming (SCOOP) and Java. Other goals include the analysis of security properties also using specific type systems.
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In the celebration of the Oswaldo Cruz Institute centenary, we wanted to stress our concern with the relationship between two of its missions: research and education. What are the educational bases required for science and technology activities on health sciences for the future years? How can scientists collaborate to promote the popularization of academic knowledge and to improve a basic education for citizenship in an ethic and humanistic view? In this article we pointed out to need of commitment, even in the biomedical post-graduation level, of a more integrated philosophy that would be centered on health education, assuming health as a dynamic biological and social equilibrium and emphasizing the need of scientific popularization of science in a cooperative construction way, instead of direct transfer of knowledge, preserving also macro views of health problems in the development of very specific studies. The contemporary explosion of knowledge, particularly biological knowledge, imposes a need of continuous education to face the growing illiteracy. In order to face this challenge, we think that the Oswaldo Cruz Institute honors his dialectic profile of tradition and transformation, always creating new perspectives to disseminate scientific culture in innovated forms.
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Projecte de recerca elaborat a partir d’una estada a la National University of Singapore Singapur, entre juliol i octubre del 2007. Donada l'explosió de la música a l'internet i la ràpida expansió de les col•leccions de música digital, un repte clau en l'àrea de la informació musical és el desenvolupament de sistemes de processament musical eficients i confiables. L'objectiu de la investigació proposada ha estat treballar en diferents aspectes de l'extracció, modelatge i processat del contingut musical. En particular, s’ha treballat en l'extracció, l'anàlisi i la manipulació de descriptors d'àudio de baix nivell, el modelatge de processos musicals, l'estudi i desenvolupament de tècniques d'aprenentatge automàtic per a processar àudio, i la identificació i extracció d'atributs musicals d'alt nivell. S’han revisat i millorat alguns components d'anàlisis d'àudio i revisat components per a l'extracció de descriptors inter-nota i intra-nota en enregistraments monofónics d'àudio. S’ha aplicat treball previ en Tempo a la formalització de diferents tasques musicals. Finalment, s’ha investigat el processat d'alt nivell de música basandonos en el seu contingut. Com exemple d'això, s’ha investigat com músics professionals expressen i comuniquen la seva interpretació del contingut musical i emocional de peces musicals, i hem usat aquesta informació per a identificar automàticament intèrprets. S’han estudiat les desviacions en paràmetres com to, temps, amplitud i timbre a nivell inter-nota i intra-nota.
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Cryptococcal infection had an increased incidence in last years due to the explosion of acquired immune deficiency syndrome epidemic and by using new and effective immunosuppressive agents. The currently antifungal therapies used such as amphotericin B, fluconazole, and itraconazole have certain limitations due to side effects and emergence of resistant strains. So, a permanent search to find new drugs for cryptococcosis treatment is essential. Ocimum gratissimum, plant known as alfavaca (Labiatae family), has been reported earlier with in vitro activity against some bacteria and dermatophytes. In our work, we study the in vitro activity of the ethanolic crude extract, ethyl acetate, hexane, and chloroformic fractions, essential oil, and eugenol of O. gratissimum using an agar dilution susceptibility method towards 25 isolates of Cryptococcus neoformans. All the extracts of O. gratissimum studied showed activity in vitro towards C. neoformans. Based on the minimal inhibitory concentration values the most significant results were obtained with chloroformic fraction and eugenol. It was observed that chloroformic fraction inhibited 23 isolates (92%) of C. neoformans at a concentration of 62.5 µg/ml and eugenol inhibited 4 isolates (16%) at a concentration of 0.9 µg/ml. This screening may be the basis for the study of O. gratissimum as a possible antifungal agent.