1,634 research outputs found

    It\u27s Not What You Do Its the Way That You Do It: the Influence of Obesity on the Speed and Accuracy of a Discrete Aiming Task

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    The ability to control speed and accuracy of goal directed aiming tasks underpins many activities of daily living. Recent evidence has begun to suggest that obesity can affect the control of movement. This study evaluated perceptual motor control of 183 normal weight, overweight, and obese participants using a discrete Fitts’ task on a digital tablet. In addition, we manipulated tablet orientation to determine whether tablet orientation influences task difficulty with the view to increase the task’s constraints. Our study found that the traditional relationship between target distance and target width hold true for each of the three weight groups in both tablet orientations. Interestingly, no significant differences were found for movement time between the groups, while movement kinematics differed between weight groups. Obese participants demonstrated significantly higher peak acceleration values in the horizontal tablet orientation when compared to their normal weight and overweight counterparts. Further to this, obese participants made significantly more errors than normal weight and overweight groups. These findings suggest that obese individuals have altered control strategies compared to their normal weight peers. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature

    Generative data-driven approaches for stochastic subgrid parameterizations in an idealized ocean model

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    Subgrid parameterizations of mesoscale eddies continue to be in demand for climate simulations. These subgrid parameterizations can be powerfully designed using physics and/or data-driven methods, with uncertainty quantification. For example, Guillaumin and Zanna (2021) proposed a Machine Learning (ML) model that predicts subgrid forcing and its local uncertainty. The major assumption and potential drawback of this model is the statistical independence of stochastic residuals between grid points. Here, we aim to improve the simulation of stochastic forcing with generative models of ML, such as Generative adversarial network (GAN) and Variational autoencoder (VAE). Generative models learn the distribution of subgrid forcing conditioned on the resolved flow directly from data and they can produce new samples from this distribution. Generative models can potentially capture not only the spatial correlation but any statistically significant property of subgrid forcing. We test the proposed stochastic parameterizations offline and online in an idealized ocean model. We show that generative models are able to predict subgrid forcing and its uncertainty with spatially correlated stochastic forcing. Online simulations for a range of resolutions demonstrated that generative models are superior to the baseline ML model at the coarsest resolution

    Théùtralité et arts visuels : le paradoxe du spectateur. Autour « The World as a Stage » et « Un teatre sense teatre »

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    La notion de thĂ©ĂątralitĂ©, d’apparition tardive, exprime dĂšs le dĂ©but un dĂ©placement du thĂ©Ăątre par rapport Ă  lui-mĂȘme. Reprise et controversĂ©e dans l’art contemporain, elle montre non seulement un dĂ©placement thĂ©orique et esthĂ©tique, mais aussi une dialectique particuliĂšre du regard. L’analyse de deux expositions « The World as a Stage » et « Un teatre sense teatre » permet de voir comment la thĂ©ĂątralitĂ© transforme notre perception de l’Ɠuvre d’art dans des propositions artistiques non-thĂ©atrales.The recent notion of theatricality expresses since its inception the idea of a displacement of theatre in relation to itself. Revived and subject to some controversies in contemporary art, it shows not only a theoretical and aesthetic displacement, but also a specific dialectic of the glance. The analysis of two exhibitions, “The World as a Stage” and “Un teatre sense teatre” allows us to see how theatricality transforms our perception of the work of art in artistic proposals that are non-theatrical

    Transposition en architecture des connaissances d’ingĂ©nierie environnementale et des savoirs relatifs au choix des matĂ©riaux

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    Les dĂ©marches environnementales s’accompagnent de plus en plus d’approches et d’outils d’aide Ă  la conception. Toutefois, ces savoir-faire techniques s’avĂšrent peu exploitĂ©s dans les projets architecturaux. Partant de ce constat, notre recherche porte sur la qualitĂ© environnementale des matĂ©riaux et procĂ©dĂ©s de mise en Ɠuvre. Elle vise Ă  alimenter, par la mise au jour de savoirs et de mĂ©thodes innovantes, les pratiques opĂ©rationnelles en architecture. \ud La mise au jour d'outils d'aide Ă  la conception simplifiĂ©e informant un public non spĂ©cialiste sur diffĂ©rents champs d'Ă©tudes explicites et relatifs Ă  la qualitĂ© des matĂ©riaux, est une Ă©volution importante dans le domaine de l’architecture.Nous avançons diffĂ©rentes propositions innovantes pour l’intelligibilitĂ© et la cohĂ©rence de futurs outils d’aide Ă  la conception. Nous les illustrons par la mise en place d’un prototype d’outil MaTerre’iO renseignant globalement les concepteurs en architecture sur les savoirs liĂ©s aux matĂ©riaux et plus spĂ©cifiquement sur les connaissances de l’ingĂ©nierie environnementale.\ud La principale retombĂ©e de notre travail de recherche est de contribuer Ă  Ă©difier une passerelle innovante entre les disciplines-----------------------------------------------------------------------------------------------------------------------------Nowadays, environmental proceedings can use more and more methods and design tools to start with the conception. However, these technical methods turn out to be untapped into architectural projects. This question orientated our research towards environmental quality of materials and processes of implementation. Through the update of the knowledge and innovative methods, our work tends to increase the capacity of operational practice in architecture. \ud The implementation of a design assistance tool - easy to use for non experts and providing several clearly configuration fields, based on caseworks and linked to quality of materials - is a significant evolution in architectural communities. \ud We point up several innovative propositions for future design assistance tools. We illustrate it by the setting up of a prototype named MaTerre’iO. This mock up informs architectural designers about the knowledge upon materials, and more specifically on the environmental engineering knowledge.\ud The main repercussion of our researched work is to contribute to initiate an innovating interface between environmental engineering topics and expectations of architectural design.\ud \u

    Disentangling the origins of cultivated sweet potato (Ipomoea batatas (L.) Lam.)

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    Sweet potato (Ipomoea batatas (L.) Lam., Convolvulaceae) counts among the most widely cultivated staple crops worldwide, yet the origins of its domestication remain unclear. This hexaploid species could have had either an autopolyploid origin, from the diploid I. trifida, or an allopolyploid origin, involving genomes of I. trifida and I. triloba. We generated molecular genetic data for a broad sample of cultivated sweet potatoes and its diploid and polyploid wild relatives, for noncoding chloroplast and nuclear ITS sequences, and nuclear SSRs. Our data did not support an allopolyploid origin for I. batatas, nor any contribution of I. triloba in the genome of domesticated sweet potato. I. trifida and I. batatas are closely related although they do not share haplotypes. Our data support an autopolyploid origin of sweet potato from the ancestor it shares with I. trifida, which might be similar to currently observed tetraploid wild Ipomoea accessions. Two I. batatas chloroplast lineages were identified. They show more divergence with each other than either does with I. trifida. We thus propose that cultivated I. batatas have multiple origins, and evolved from at least two distinct autopolyploidization events in polymorphic wild populations of a single progenitor species. Secondary contact between sweet potatoes domesticated in Central America and in South America, from differentiated wild I. batatas populations, would have led to the introgression of chloroplast haplotypes of each lineage into nuclear backgrounds of the other, and to a reduced divergence between nuclear gene pools as compared with chloroplast haplotypes. (Résumé d'auteur

    Approches à base de fréquences pour la simplification lexicale

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    National audienceLa simplification lexicale consiste Ă  remplacer des mots ou des phrases par leur Ă©quivalent plus simple. Dans cet article, nous prĂ©sentons trois modĂšles de simplification lexicale, fondĂ©s sur diffĂ©rents critĂšres qui font qu'un mot est plus simple Ă  lire et Ă  comprendre qu'un autre. Nous avons testĂ© diffĂ©rentes tailles de contextes autour du mot Ă©tudiĂ© : absence de contexte avec un modĂšle fondĂ© sur des frĂ©quences de termes dans un corpus d'anglais simplifiĂ© ; quelques mots de contexte au moyen de probabilitĂ©s Ă  base de n-grammes issus de donnĂ©es du web ; et le contexte Ă©tendu avec un modĂšle fondĂ© sur les frĂ©quences de cooccurrences. ABSTRACT Studying frequency-based approaches to process lexical simplification Lexical simplification aims at replacing words or phrases by simpler equivalents. In this paper, we present three models for lexical simplification, focusing on the criteria that make one word simpler to read and understand than another. We tested different contexts of the considered word : no context, with a model based on word frequencies in a simplified English corpus ; a few words context, with n-grams probabilites on Web data, and an extended context, with a model based on co-occurrence frequencies. MOTS-CLÉS : simplification lexicale, frĂ©quence lexicale, modĂšle de langue

    The GH51 α-l-arabinofuranosidase from Paenibacillus sp. THS1 is multifunctional, hydrolyzing main-chain and side-chain glycosidic bonds in heteroxylans.

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    Background: Conceptually, multi functional enzymes are attractive because in the case of complex polymer hydrolysis having two or more activities defined by a single enzyme offers the possibility of synergy and reduced enzyme cocktail complexity. Nevertheless, multi functional enzymes are quite rare and are generally multi domain assemblies with each activity being defined by a separate protein module. However, a recent report described a GH51 arabinofuranosidase from Alicyclobacillus sp. A4 that displays both α l arabinofuranosidase and ÎČ d xylanase activities, which are defined by a single active site. Following on from this, we describe in detail another multi functional GH51 arabinofuranosidase and discuss the molecular basis of multifunctionality. Results: THSAbf is a GH51 α l arabinofuranosidase. Characterization revealed that THSAbf is active up to 75 °C, stable at 60 °C and active over a broad pH range (4–7). THSAbf preferentially releases para nitrophenyl from the l arabino furanoside ( k cat / K M = 1050 s − 1 mM − 1 ) and to some extent from d galactofuranoside and d xyloside. THSAbf is active on 4 O methylglucuronoxylans from birch and beechwood (10.8 and 14.4 U mg − 1 , respectively) and on sugar beet branched and linear arabinans (1.1 ± 0.24 and 1.8 ± 0.1 U mg − 1 ). Further investigation revealed that like the Alicyclo - bacillus sp. A4 α l arabinofuranosidase, THSAbf also displays endo xylanase activity, cleaving ÎČ 1,4 bonds in heteroxy lans. The optimum pH for THASAbf activity is substrate dependent, but ablation of the catalytic nucleophile caused a general loss of activity, indicating the involvement of a single active center. Combining the α l arabinofuranosidase with a GH11 endoxylanase did not procure synergy. The molecular modeling of THSAbf revealed a wide active site cleft and clues to explain multi functionality

    Storage oil hydrolysis during early seedling growth

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    Storage oil breakdown plays an important role in the life cycle of many plants by providing the carbon skeletons that support seedling growth immediately following germination. This metabolic process is initiated by lipases (EC: 3.1.1.3), which catalyze the hydrolysis of triacylglycerols (TAGs) to release free fatty acids and glycerol. A number of lipases have been purified to near homogeneity from seed tissues and analysed for their in vitro activities. Furthermore, several genes encoding lipases have been cloned and characterised from plants. However, only recently has data been presented to establish the molecular identity of a lipase that has been shown to be required for TAG breakdown in seeds. In this review we briefly outline the processes of TAG synthesis and breakdown. We then discuss some of the biochemical literature on seed lipases and describe the cloning and characterisation of a lipase called SUGAR-DEPENDENT1, which is required for TAG breakdown in Arabidopsis thaliana seeds

    Filling a blank on the map: 60 years of fisheries in Equatorial Guinea

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    Despite a scarcity of pertinent information, it has been possible to reconstruct time series of marine fisheries catches for Equatorial Guinea from 1950 to 2010 using per capita fish consumption and population numbers for small-scale fisheries, catch rates and number of vessels for industrial fisheries and discard rates to estimate the discarded bycatch. Small-scale fisheries, industrial large-scale fisheries, domestic and legal and illegal foreign fisheries and their discards are all included. Total catches were estimated at 2.7 million tonnes over the time period considered, of which 653 000 t were caught domestically compared to 187 000 t reported by FAO. This shows that fisheries have more importance for Equatorial Guinea's food security than the official data suggest. In contrast to what is suggested by official figures, fisheries were shown to be strongly impacted by civil and political unrest; notably, they declined overall because of civil and political conflicts, socio-demographic dynamics, and a growing role of the newly discovered oil resources, which directly and indirectly threaten the food security of the people of Equatorial Guinea
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