500 research outputs found

    Neighborhood and physical activities of Portuguese adolescents

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    <p>Abstract</p> <p>Background</p> <p>This study examines associations between perceptions of neighbourhood environment and physical activity and sports within Portuguese adolescents.</p> <p>Methods</p> <p>The sample consisted of 4,877 individuals of both genders, with an average age of 14 years. The instrument used was the Health Behavior School-aged Children questionnaire.</p> <p>Results</p> <p>Perceptions of the neighbourhood being unsafe for children to play and having no place to spend leisure time were associated with lower levels of exercise among adolescents. The perceptions of the neighbourhood being unsafe for children to play (OR = 1.3, p < .005) and the fact of not having a place to spend leisure time (OR = 1.3, p < .005) p < .005) were associated with lower levels of exercise among adolescents. The perception of these variables is associated to a lower probability of exercising. The neighbourhood characteristics are more important to the practice of outdoor sports than of indoor sports.</p> <p>Conclusion</p> <p>The perceptions of the neighbourhood may influence adolescent's physical activity and sports, in different ways.</p

    On Modeling the Quality of Nutrition for Healthy Ageing Using Fuzzy Cognitive Maps

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    Modelling dietary intake of older adults can prevent nutritional deficiencies and diet-related diseases, improving their quality of life. Towards such direction, a Fuzzy Cognitive Map (FCM)-based modelling approach that models the interdependencies between the factors that affect the Quality of Nutrition (QoN) is presented here. The proposed FCM-QoN model uses a FCM with seven input-one output concepts, i.e., five food groups of the UK Eatwell Plate, Water (H2O), and older adult’s Emotional State (EmoS), outputting the QoN. The weights incorporated in the FCM structure were drawn from an experts’ panel, via a Fuzzy Logic-based knowledge representation process. Using various levels of analysis (causalities, static/feedback cycles), the role of EmoS and H2O in the QoN was identified, along with the one of Fruits/Vegetables and Protein affecting the sustainability of effective food combinations. In general, the FCM-QoN approach has the potential to explore different dietary scenarios, helping health professionals to promote healthy ageing and providing prognostic simulations for diseases effect (such as Parkinson’s) on dietary habits, as used in the H2020 i-Prognosis project (www.i-prognosis.eu)

    Community phylogenetics at the biogeographical scale: cold tolerance, niche conservatism and the structure of North American forests

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    Aim The fossil record has led to a historical explanation for forest diversity gradients within the cool parts of the Northern Hemisphere, founded on a limited ability of woody angiosperm clades to adapt to mid-Tertiary cooling. We tested four predictions of how this should be manifested in the phylogenetic structure of 91,340 communities: (1) forests to the north should comprise species from younger clades (families) than forests to the south; (2) average cold tolerance at a local site should be associated with the mean family age (MFA) of species; (3) minimum temperature should account for MFA better than alternative environmental variables; and (4) traits associated with survival in cold climates should evolve under a niche conservatism constraint. Location The contiguous United States. Methods We extracted angiosperms from the US Forest Service's Forest Inventory and Analysis database. MFA was calculated by assigning age of the family to which each species belongs and averaging across the species in each community. We developed a phylogeny to identify phylogenetic signal in five traits: realized cold tolerance, seed size, seed dispersal mode, leaf phenology and height. Phylogenetic signal representation curves and phylogenetic generalized least squares were used to compare patterns of trait evolution against Brownian motion. Eleven predictors structured at broad or local scales were generated to explore relationships between environment and MFA using random forest and general linear models. Results Consistent with predictions, (1) southern communities comprise angiosperm species from older families than northern communities, (2) cold tolerance is the trait most strongly associated with local MFA, (3) minimum temperature in the coldest month is the environmental variable that best describes MFA, broad-scale variables being much stronger correlates than local-scale variables, and (4) the phylogenetic structures of cold tolerance and at least one other trait associated with survivorship in cold climates indicate niche conservatism. Main conclusions Tropical niche conservatism in the face of long-term climate change, probably initiated in the Late Cretaceous associated with the rise of the Rocky Mountains, is a strong driver of the phylogenetic structure of the angiosperm component of forest communities across the USA. However, local deterministic and/or stochastic processes account for perhaps a quarter of the variation in the MFA of local communities

    Phylogenetic structure of geographical co-occurrence among New World Triatominae species, vectors of Chagas disease

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    The tropical niche conservatism (TNC) hypothesis is one of the most prominent evolutionary hypotheses that has been supported as an explanation for the diversity gradients of several animal taxa, mainly vertebrates. However, the validity of TNC for less-known taxa such as disease vectors is not clear. Here, we test predictions of TNC in driving the geographical co-occurrence among triatomine species, vector insects of Chagas disease. We aim to infer the relative effects of ecological and evolutionary processes in determining triatomine species richness at broad spatial scales. Location: America. Taxon: Triatominae (Hemiptera: Reduviidae). Methods: We gathered distributional, phylogenetic and climatic information for 63 triatomine species. We apply the phylogenetic field (PF) framework based on the phylogenetic structure of species co-occurrences, considering their climatic preferences. We defined PFs of species by estimating the phylogenetic structure of species co-occurrence within a focal species’ range. Likewise, climatic conditions within focal species’ ranges were defined as their preferred climates. We applied a spatial-phylogenetic statistical framework to evaluate geographical variation of species’ co-occurrence and tested the significance of PFs based on biogeographically informed null models. Results: Phylogenetic fields of 17 out of 59 triatomine species showed a trend from overdispersed to clustered, coincident with tropical to subtropical–temperate climate. Triatomines co-occur with more closely related species in temperate areas and more distantly related species in tropical areas. Temperature seasonality was inversely related to the phylogenetic structure of co-occurrence within species ranges. Main conclusions: Geographical co-occurrence among triatomine species revealed a tropical to subtropical–temperate gradient from overdispersed to clustered PFs and a correspondence between the type of climate in which these species are found and their PFs. Phylogenetic structure within triatomine ranges is explained by their evolutionary history. Our study provides a methodological framework to evaluate the New World triatomine geographical co-occurrence patterns under a phylogenetic perspective and our results make an important contribution to the understanding of the broad-scale biodiversity patterns in Triatominae.Fil: Ceccarelli, Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Justi, Silvia A.. Smithsonian Institution Museum Support Center; Estados Unidos. Walter Reed Army Institute of Research. Entomology Branch; Estados UnidosFil: Rabinovich, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Diniz Filho, José Alexandre F.. Universidade Federal de Goiás; BrasilFil: Villalobos, Fabricio. Universidade Federal de Goiás; Brasil. Instituto de Ecología; Méxic

    Modeling the ecology and evolution of biodiversity: Biogeographical cradles, museums, and graves

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    Individual processes shaping geographical patterns of biodiversity are increasingly understood, but their complex interactions on broad spatial and temporal scales remain beyond the reach of analytical models and traditional experiments. To meet this challenge, we built a spatially explicit, mechanistic simulation model implementing adaptation, range shifts, fragmentation, speciation, dispersal, competition, and extinction, driven by modeled climates of the past 800,000 years in South America. Experimental topographic smoothing confirmed the impact of climate heterogeneity on diversification. The simulations identified regions and episodes of speciation (cradles), persistence (museums), and extinction (graves). Although the simulations had no target pattern and were not parameterized with empirical data, emerging richness maps closely resembled contemporary maps for major taxa, confirming powerful roles for evolution and diversification driven by topography and climate

    Timely and effectively profile bacteria in cystic fibrosis lungs

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    Bacterial lung infections are typical of cystic fibrosis (CF) disease due to accumulation of airway mucus. Despite the use of aggressive antibiotic therapy, the mortality rate of CF patients is still high. Unsuccessful bacterial eradication is often due to several evolutional strategies adopted by bacteria to achieve anaerobic or microaerophilic adaptation and antibiotic resistance, such as biofilm formation and phenotypic switching. By triggering these strategies, bacteria have the potential to better survive to airway stressful conditions, without the fitness costs of irreversible mutations. Indeed, phenotypic switching provides a source of microbial diversity through interchange between phenotypic states, analogue to a mechanism ON/OFF. This interchange of states, often visible in terms of colony morphology, can have serious impact on bacterial virulence, antimicrobial resistance and persistence1. However, the specific correlation between some colony traits and the biological impact is unknown. This study was designed to inspect P. aeruginosa and S. aureus colony phenotypic alterations, particularly morphology changes, by visual inspection, and protein profiles by MALDI MS, and correlate them with some virulence determinants expression and antibiotic susceptibility profiles. The visual identification of colony morphologies was supported by a novel, in-house developed identification system, ColMIS2. MALDI MS profiling grouped colony morphotypes differently from conventional morphological classification and antibiotic susceptibility. However, MALDI MS colony differentiation seems to match with changes in some virulence factors expressed by the different bacterial morphotypes, such as the increase of flagella, swarmer cell differentiation, ability to form biofilm and toxin production. Despite exhibiting distinct colony morphologies, the variants grouped by MALDI shared a common morphological feature, the heterogeneity of colony surface (more than one type of texture). Therefore, these data seems to indicate that MALDI MS clustered colony variants according their virulence that can be inspected by just the heterogeneous surface of the colonies, than the whole morphology. However, this association have to be deeper studied, since other colonies with heterogeneous surfaces were differentially clustered by MALDI MS and, despite decreased virulence, exhibited high resistance to in-use antibiotics. These results highlighted the potential and the need of using a combination of proteomic high-throughput screening of pathogenic bacteria with culturing and physiologic methods to reach a comprehensive understanding of the virulence and antibiotic resistance. Efforts are already underway to develop a new tool based on combinatorial methodologies to help clinical diagnosis and medical decision support, as well the design of new therapeutic strategies. Acknowledgments: The financial support from IBB-CEB and FCT and European Community fund FEDER, through Program COMPETE (FCT PTDC/SAU-SAP/113196/2009/ FCOMP-01-0124-FEDER-016012) and Ana Margarida Sousa PhD Grant (SFRH/BD/72551/2010) are gratefully acknowledged

    Community phylogenetics at the biogeographical scale: cold tolerance, niche conservatism and the structure of North American forests

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    Aim The fossil record has led to a historical explanation for forest diversity gradients within the cool parts of the Northern Hemisphere, founded on a limited ability of woody angiosperm clades to adapt to mid-Tertiary cooling. We tested four predictions of how this should be manifested in the phylogenetic structure of 91,340 communities: (1) forests to the north should comprise species from younger clades (families) than forests to the south; (2) average cold tolerance at a local site should be associated with the mean family age (MFA) of species; (3) minimum temperature should account for MFA better than alternative environmental variables; and (4) traits associated with survival in cold climates should evolve under a niche conservatism constraint. Location The contiguous United States. Methods We extracted angiosperms from the US Forest Service's Forest Inventory and Analysis database. MFA was calculated by assigning age of the family to which each species belongs and averaging across the species in each community. We developed a phylogeny to identify phylogenetic signal in five traits: realized cold tolerance, seed size, seed dispersal mode, leaf phenology and height. Phylogenetic signal representation curves and phylogenetic generalized least squares were used to compare patterns of trait evolution against Brownian motion. Eleven predictors structured at broad or local scales were generated to explore relationships between environment and MFA using random forest and general linear models. Results Consistent with predictions, (1) southern communities comprise angiosperm species from older families than northern communities, (2) cold tolerance is the trait most strongly associated with local MFA, (3) minimum temperature in the coldest month is the environmental variable that best describes MFA, broad-scale variables being much stronger correlates than local-scale variables, and (4) the phylogenetic structures of cold tolerance and at least one other trait associated with survivorship in cold climates indicate niche conservatism. Main conclusions Tropical niche conservatism in the face of long-term climate change, probably initiated in the Late Cretaceous associated with the rise of the Rocky Mountains, is a strong driver of the phylogenetic structure of the angiosperm component of forest communities across the USA. However, local deterministic and/or stochastic processes account for perhaps a quarter of the variation in the MFA of local communities

    Set-Membership Proportionate Affine Projection Algorithms

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    Proportionate adaptive filters can improve the convergence speed for the identification of sparse systems as compared to their conventional counterparts. In this paper, the idea of proportionate adaptation is combined with the framework of set-membership filtering (SMF) in an attempt to derive novel computationally efficient algorithms. The resulting algorithms attain an attractive faster converge for both situations of sparse and dispersive channels while decreasing the average computational complexity due to the data discerning feature of the SMF approach. In addition, we propose a rule that allows us to automatically adjust the number of past data pairs employed in the update. This leads to a set-membership proportionate affine projection algorithm (SM-PAPA) having a variable data-reuse factor allowing a significant reduction in the overall complexity when compared with a fixed data-reuse factor. Reduced-complexity implementations of the proposed algorithms are also considered that reduce the dimensions of the matrix inversions involved in the update. Simulations show good results in terms of reduced number of updates, speed of convergence, and final mean-squared error

    Benchmark Rovibrational Linelists and Einstein A-coefficients for the Primordial Molecules and Isotopologues

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    Complete benchmark rovibrational energy linelists calculated for the primordial polar molecules of the universe, namely HD+, HD, and the HeH+ isotopologues, with accuracy up to 10(-2) cm(-1) for low-lying states, are presented. To allow for these calculations to be performed, new high-accuracy potential energy curves, which include the diagonal Born-Oppenheimer adiabatic corrections and the leading relativistic corrections, are determined. Also, a new approach for calculating non-adiabatic corrections involving an effective vibrational nuclear mass obtained based on the atoms-in-molecules theory is employed. The vibrational and rotational masses are taken as being different and dependent on the nuclear distance. Accurate dipole moment curves are calculated and used to generate lists of Einstein A-coefficients. The energy linelists and the sets of Einstein A-coefficients for HD are upgrades of previous calculations including quasibound states, while for HD+ and HeH+ and its isotopologues the present results represent significant improvement over the previous calculations. The results obtained here suggest that, with the inclusion of the non-adiabatic corrections, the accuracy limit at least for low-lying states might have been reached. Thus, further progress should involve accounting for even smaller effects such as the quantum-electrodynamics corrections. The present results represent the state-of-the-art of theoretical spectroscopy of the primordial polar molecules.CAPES; Polish National Science Centre [DEC-2013/10/E/ST4/00033]; CNPqThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
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