949 resultados para Corina Chacon Navas


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Frog jumping is an excellent model system for examining the structural basis of interindividual variation in burst locomotor performance. Some possible factors that affect jump performance, such as total body size, hindlimb length, muscle mass, and muscle mechanical and biochemical properties, were analysed at the interindividual (intraspecies) level in the tree frog Hyla multilineata. The aim of this study was to determine which of these physiological and anatomical variables both vary between individuals and are correlated with interindividual variation in jump performance. The model produced via stepwise linear regression analysis of absolute data suggested that 62% of the interindividual variation in maximum jump distance could be explained by a combination of interindividual variation in absolute plantaris muscle mass, total hindlimb muscle mass ( excluding plantaris muscle), and pyruvate kinase activity. When body length effects were removed, multiple regression indicated that the same independent variables explained 43% of the residual interindividual variation in jump distance. This suggests that individuals with relatively large jumping muscles and high pyruvate kinase activity for their body size achieved comparatively large maximal jump distances for their body size.

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Over the last 50 yr, thermal biology has shifted from a largely physiological science to a more integrated science of behavior, physiology, ecology, and evolution. Today, the mechanisms that underlie responses to environmental temperature are being scrutinized at levels ranging from genes to organisms. From these investigations, a theory of thermal adaptation has emerged that describes the evolution of thermoregulation, thermal sensitivity, and thermal acclimation. We review and integrate current models to form a conceptual model of coadaptation. We argue that major advances will require a quantitative theory of coadaptation that predicts which strategies should evolve in specific thermal environments. Simply combining current models, however, is insufficient to understand the responses of organisms to thermal heterogeneity; a theory of coadaptation must also consider the biotic interactions that influence the net benefits of behavioral and physiological strategies. Such a theory will be challenging to develop because each organism's perception of and response to thermal heterogeneity depends on its size, mobility, and life span. Despite the challenges facing thermal biologists, we have never been more pressed to explain the diversity of strategies that organisms use to cope with thermal heterogeneity and to predict the consequences of thermal change for the diversity of communities.

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Two of the greatest crises that civilisation faces in the 21st century are the predicted rapid increases in the ageing population and levels of metabolic disorders such as obesity and type 2 diabetes. A growing amount of evidence now supports the notion that energy balance is a key determinant not only in metabolism but also in the process of cellular ageing. Much of genetic evidence for a metabolic activity-driven ageing process has come from model organisms such as worms and flies where inactivation of the insulin receptor signalling cascade prolongs lifespan. At its most simplistic, this poses a conundrum for ageing in humans – can reduced insulin receptor signalling really promote lifespan and does this relate to insulin resistance seen in ageing? In higher animals, caloric restriction studies have confirmed a longer lifespan when daily calorie intake is reduced to 60% of normal energy requirement. This suggests that for humans, it is energy excess which is a likely driver of metabolic ageing. Interventions that interfere with the metabolic fate of nutrients offer a potentially important target for delaying biological ageing.

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Increasingly, lab evaluations of mobile applications are incorporating mobility. The inclusion of mobility alone, however, is insufficient to generate a realistic evaluation context since real-life users will typically be required to monitor their environment while moving through it. While field evaluations represent a more realistic evaluation context, such evaluations pose difficulties, including data capture and environmental control, which mean that a lab-based evaluation is often a more practical choice. This paper describes a novel evaluation technique that mimics a realistic mobile usage context in a lab setting. The technique requires that participants monitor their environment and change the route they are walking to avoid dynamically changing hazards (much as reallife users would be required to do). Two studies that employed this technique are described, and the results (which indicate the technique is useful) are discussed.

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Despite being nominated as a key potential interaction technique for supporting today's mobile technology user, the widespread commercialisation of speech-based input is currently being impeded by unacceptable recognition error rates. Developing effective speech-based solutions for use in mobile contexts, given the varying extent of background noise, is challenging. The research presented in this paper is part of an ongoing investigation into how best to incorporate speechbased input within mobile data collection applications. Specifically, this paper reports on a comparison of three different commercially available microphones in terms of their efficacy to facilitate mobile, speech-based data entry. We describe, in detail, our novel evaluation design as well as the results we obtained.

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The exponential growth of studies on the biological response to ocean acidification over the last few decades has generated a large amount of data. To facilitate data comparison, a data compilation hosted at the data publisher PANGAEA was initiated in 2008 and is updated on a regular basis (doi:10.1594/PANGAEA.149999). By January 2015, a total of 581 data sets (over 4 000 000 data points) from 539 papers had been archived. Here we present the developments of this data compilation five years since its first description by Nisumaa et al. (2010). Most of study sites from which data archived are still in the Northern Hemisphere and the number of archived data from studies from the Southern Hemisphere and polar oceans are still relatively low. Data from 60 studies that investigated the response of a mix of organisms or natural communities were all added after 2010, indicating a welcomed shift from the study of individual organisms to communities and ecosystems. The initial imbalance of considerably more data archived on calcification and primary production than on other processes has improved. There is also a clear tendency towards more data archived from multifactorial studies after 2010. For easier and more effective access to ocean acidification data, the ocean acidification community is strongly encouraged to contribute to the data archiving effort, and help develop standard vocabularies describing the variables and define best practices for archiving ocean acidification data.

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The objective of this study is to investigate how the team of health professionals of the Family Health Strategies program and clients in Currais Novos/RN deal with the use (or not) of medicinal plants as one of the complementary and holistic practices in the Individual Health System (SUS in Portuguese). The research is carried out using a qualitative approach, applying semi-structured interviews, related to the proposed objective, as the instruments of data collection. The interviews applied to professionals and clients were based on questionnaires and were recorded, with their permission, then transcribed in a field diary. The subjects of the study were doctors, nurses, dentists and community health agents of the Family Health Strategies team, totaling 24 (twenty four) health professionals, as well as ten volunteers identified in the research as people who use medicinal plants for health care purposes. From this study, we verify the great importance that health professionals and clients attribute to the use of medicinal plants, as well as evidence that family tradition is the main vehicle for the dissemination of knowledge regarding their use. Most medicinal plants had popular indications similar of those used scientifically, however, 70% of the clients reported never having had medical health advice or encouragement to use medicinal plants in their treatments. Half of the group of professionals interviewed reported not feeling safe in prescribing medicinal plants; approximately 25% reported having received information on the subject during their undergraduate program. Expected outcomes of this study include instigating the implementation of treatment protocols by the health professionals, and broadening holistic care practices, as well as access to alternative therapeutic options, client participation, ultimately strengthening the link between primary care and Family Health Strategies

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Wireless Sensor and Actuator Networks (WSAN) are a key component in Ubiquitous Computing Systems and have many applications in different knowledge domains. Programming for such networks is very hard and requires developers to know the available sensor platforms specificities, increasing the learning curve for developing WSAN applications. In this work, an MDA (Model-Driven Architecture) approach for WSAN applications development called ArchWiSeN is proposed. The goal of such approach is to facilitate the development task by providing: (i) A WSAN domain-specific language, (ii) a methodology for WSAN application development; and (iii) an MDA infrastructure composed of several software artifacts (PIM, PSMs and transformations). ArchWiSeN allows the direct contribution of domain experts in the WSAN application development without the need of specialized knowledge on WSAN platforms and, at the same time, allows network experts to manage the application requirements without the need for specific knowledge of the application domain. Furthermore, this approach also aims to enable developers to express and validate functional and non-functional requirements of the application, incorporate services offered by WSAN middleware platforms and promote reuse of the developed software artifacts. In this sense, this Thesis proposes an approach that includes all WSAN development stages for current and emerging scenarios through the proposed MDA infrastructure. An evaluation of the proposal was performed by: (i) a proof of concept encompassing three different scenarios performed with the usage of the MDA infrastructure to describe the WSAN development process using the application engineering process, (ii) a controlled experiment to assess the use of the proposed approach compared to traditional method of WSAN application development, (iii) the analysis of ArchWiSeN support of middleware services to ensure that WSAN applications using such services can achieve their requirements ; and (iv) systematic analysis of ArchWiSeN in terms of desired characteristics for MDA tool when compared with other existing MDA tools for WSAN.

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The Brazilian writer, Caio Fernando Abreu, was strongly influenced by a period of changes in social values and perspectives. When he enters the Brazilian literary scene using a writing style free from form and content, he applies in his works all the affliction of the contemporary values. His work embodies all the spirit of a generation that, despite its anxiety for freedom, was still suffocated by the military dictatorship period. Abreu’s narrative also reveals an author with an extreme ability to shift between the erudite and the popular. In his short stories, he develops a performative language mingled by references that turns his text into a sort of Pop Art iconography. Just like Pop Art paintings, full of Coke images, cigarettes, tooth paste and food cans, Abreu’s literary discourse is painted by many symbolical references to modern consumerism, as well as to movies, music and to pop stars. This trace in the writer’s works exerts a great deal of attractiveness on the contemporary reader. In this work, we attempt to analyze this resource in Abreu’s literature under the concepts of cultural studies; thus, we aim at analyzing the various forms of the mass culture expression inside Abreu’s literature, recognizing his allusions as a stylish resource in his writings and highlighting its relevance in the study of the author work. In order to do so, we are based essentially on the reflections of theoreticians: Lipovetsky (1996) and Adorno (2011) who debate the culture and social formation in contemporaneity.

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Bastantes años de práctica de la psicología educativa-comunitaria y especialmente en sus aspectos preventivos y de intervención familiar, hacen plantearse multitud de dudas que no siempre la ciencia escrita consultada resuelve de manera satisfactoria. Es difícil trabajar directamente con los adolescentes sobre los factores de riesgo de padecer TCA, por iatrogenia, pero cuando se actúa con los padres, podríamos conseguir disminuir o impedir, de manera preventiva, padecer este trastorno, sobre todo después de una detección precoz a través de sus factores de riesgo. Así, la hipótesis fundamental planteada es: la información y formación temprana a las familias sobre el desarrollo físico, emocional, social…, las estrategias educativas y de aprendizaje, el cambio y manejo de comportamientos y los criterios básicos en el establecimiento de normas y límites, podrán motivar cambio de actitud y generar estilos educativos que favorecerán la aparición de factores de protección, no solo respecto a los TCA, sino también a otras problemáticas derivadas de la crisis adolescente.. Desde la psicología comunitaria (Smetana, Campione-Barr, y Metzger, 2006) es necesario ajustar los criterios de lo que significa buena investigación en la práctica y tener claro que el objetivo es saber si la práctica implantada se ha hecho según lo previsto, se mantiene en el tiempo y los factores de sostenibilidad que hay que tener en cuenta. (Hoagwood y Johnson, 2003). Las intervenciones según el modelo de salud bio-psico-social (OMS, 1989), están íntimamente relacionadas con lo que las personas hacen, en el medio en el que normalmente se desenvuelven y con los recursos con los que cuentan (Bronfrenbenner, 2005; Tudge, Mokrova, Hatfield y Karnik, 2009). Con estos presupuestos, parece claro, que ni la familia, ni la institución educativa, ni la institución sanitaria por sí solas tienen la respuesta a tan complejas situaciones y es desde el trabajo multidisciplinar desde donde hay que abordarlas (Fernández y Vidal, 2008; Hombrados, 2013). Puede existir un desequilibrio durante la pubertad entre las áreas relacionadas con el proceso emocional y la corteza prefrontal. Este desajuste temporal puede contribuir a la desregulación emocional y un posterior riesgo de sufrir patologías, en muchos casos (Dahl y Gunnar, 2009; Ladouceur, 2012)...

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This project (PP00P1_133632/1), the first author Corina Berli (PP00P1_133632/1 and P2BEP1_158975) and the third author Jennifer Inauen (P2ZHP1_155103) were funded by the Swiss National Science Foundation.

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Peer reviewed

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The difluoromethyl-allo-threonyl hydroxamate-based compound LPC-058 is a potent inhibitor of UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine deacetylase (LpxC) in Gram-negative bacteria. A scalable synthesis of this compound is described. The key step in the synthetic sequence is a transition metal/base-catalyzed aldol reaction of methyl isocyanoacetate and difluoroacetone, giving rise to 4-(methoxycarbonyl)-5,5-disubstituted 2-oxazoline. A simple NMR-based determination of enantiomeric purity is also described.