3,564 research outputs found

    Anomalies in the carbonate system of Red Sea coastal habitats

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    © The Author(s), 2020. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Baldry, K., Saderne, V., McCorkle, D. C., Churchill, J. H., Agust, S., & Duarte, C. M. Anomalies in the carbonate system of Red Sea coastal habitats. Biogeosciences, 17(2), (2020): 423-439, doi:10.5194/bg-17-423-2020.We use observations of dissolved inorganic carbon (DIC) and total alkalinity (TA) to assess the impact of ecosystem metabolic processes on coastal waters of the eastern Red Sea. A simple, single-end-member mixing model is used to account for the influence of mixing with offshore waters and evaporation–precipitation and to model ecosystem-driven perturbations on the carbonate system chemistry of coral reefs, seagrass meadows and mangrove forests. We find that (1) along-shelf changes in TA and DIC exhibit strong linear relationships that are consistent with basin-scale net calcium carbonate precipitation; (2) ecosystem-driven changes in TA and DIC are larger than offshore variations in >70 % of sampled seagrass meadows and mangrove forests, changes which are influenced by a combination of longer water residence times and community metabolic rates; and (3) the sampled mangrove forests show strong and consistent contributions from both organic respiration and other sedimentary processes (carbonate dissolution and secondary redox processes), while seagrass meadows display more variability in the relative contributions of photosynthesis and other sedimentary processes (carbonate precipitation and oxidative processes). The results of this study highlight the importance of resolving the influences of water residence times, mixing and upstream habitats on mediating the carbonate system and coastal air–sea carbon dioxide fluxes over coastal habitats in the Red Sea.This research has been supported by the King Abdullah University of Science and Technology (KAUST) (grant nos. BAS/1/1071-01-01 and BAS/1/1072-01-01) and the Investment in Science fund at WHOI

    Fairy circle landscapes under the sea

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    Short-scale interactions yield large-scale vegetation patterns that, in turn, shape ecosystem function across landscapes. Fairy circles, which are circular patches bare of vegetation within otherwise continuous landscapes, are characteristic features of semiarid grasslands. We report the occurrence of submarine fairy circle seascapes in seagrass meadows and propose a simple model that reproduces the diversity of seascapes observed in these ecosystems as emerging from plant interactions within the meadow. These seascapes include two extreme cases, a continuous meadow and a bare landscape, along with intermediate states that range from the occurrence of persistent but isolated fairy circles, or solitons, to seascapes with multiple fairy circles, banded vegetation, and "leopard skin" patterns consisting of bare seascapes patterns consisting of bare seascapes dotted with plant patches. The model predicts that these intermediate seascapes extending across kilometers emerge as a consequence of local demographic imbalances along with facilitative and competitive interactions among the plants with a characteristic spatial scale of 20 to 30 m, consistent with known drivers of seagrass performance. The model, which can be extended to clonal growth plants in other landscapes showing fairy rings, reveals that the different seascapes observed hold diagnostic power as to the proximity of seagrass meadows to extinction points that can be used to identify ecosystems at risks

    Does the experience influence the efficacy of football coach? A perspective from coaches with different levels of experience as player and as coach

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    The experience is as an important predictor of the football coach efficacy. To study its relevance in valuation of efficacy factors we used the CESp (Duarte et al., 2010), an adapted version of the Coaching Efficacy Scale (CES), of Feltz et al. (1999), in a sample of 60 football coaches from different competitive levels working in Portugal, which were categorized according to their experience as players (professionals and non-professionals) and as coaches (high and reduced). Based on the analysis of the results it was concluded that: 1) professional experience as a player does not interfere in valuing of the efficacy factors; 2) professional experience as a coach involves a factor´s different valuation, with a significance level on character factor; 3) coaches with less experience as athletes and coaches shows less consistency in the practical application of the factors with regard to their hierarchy and frequency of its use. This is a study that allows a deeper understanding of the importance of experience in football coach performance, emphasizing the need to consider the different levels of experience in coach training, and still require subsequent studies, particulary with coaches who work in other contexts, in order to better support the applicability of the results

    Evaluating weaknesses of "perceptual-cognitive training" and "brain training" methods in sport: An ecological dynamics critique

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    The recent upsurge in "brain training and perceptual-cognitive training," proposing to improve isolated processes, such as brain function, visual perception, and decision-making, has created significant interest in elite sports practitioners, seeking to create an "edge" for athletes. The claims of these related "performance-enhancing industries" can be considered together as part of a process training approach proposing enhanced cognitive and perceptual skills and brain capacity to support performance in everyday life activities, including sport. For example, the "process training industry" promotes the idea that playing games not only makes you a better player but also makes you smarter, more alert, and a faster learner. In this position paper, we critically evaluate the effectiveness of both types of process training programmes in generalizing transfer to sport performance. These issues are addressed in three stages. First, we evaluate empirical evidence in support of perceptual-cognitive process training and its application to enhancing sport performance. Second, we critically review putative modularized mechanisms underpinning this kind of training, addressing limitations and subsequent problems. Specifically, we consider merits of this highly specific form of training, which focuses on training of isolated processes such as cognitive processes (attention, memory, thinking) and visual perception processes, separately from performance behaviors and actions. We conclude that these approaches may, at best, provide some "general transfer" of underlying processes to specific sport environments, but lack "specificity of transfer" to contextualize actual performance behaviors. A major weakness of process training methods is their focus on enhancing the performance in body "modules" (e.g., eye, brain, memory, anticipatory sub-systems). What is lacking is evidence on how these isolated components are modified and subsequently interact with other process "modules," which are considered to underlie sport performance. Finally, we propose how an ecological dynamics approach, aligned with an embodied framework of cognition undermines the rationale that modularized processes can enhance performance in competitive sport. An ecological dynamics perspective proposes that the body is a complex adaptive system, interacting with performance environments in a functionally integrated manner, emphasizing that the inter-relation between motor processes, cognitive and perceptual functions, and the constraints of a sport task is best understood at the performer-environment scale of analysis

    How do families represent the functions of deliberate self-harm? A comparison between the social representations from Adolescents and Their Parents

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    Research has recognized the importance of understanding the social representations about the functions of deliberate self-harm, particularly in the context of clinical intervention. In addition, parents can play a relevant role in the rehabilitation of adolescents with these behaviors. However, there are few studies that focused on the description and comparison of the social representations about these functions, particularly in families. This article aimed to analyze the social representations about the functions of deliberate self-harm from adolescents and their parents. We developed two sets of analyses: first we compared the social representations from adolescents without a history of deliberate self-harm and their parents, and secondly we compared the social representations about the functions of deliberate self-harm from adolescents with a history of these behaviors and their parents' social representations. Results revealed significant differences between both groups of families, implying that the groups of participants represent the functions of deliberate self-harm differently. Overall, parents emphasized interpersonal functions and devalued intrapersonal functions. These differences were heightened in the families of adolescents with deliberate self-harm. The present article provides important insights regarding the social representations about the functions of deliberate self-harm and the differences between parents' social representations and their children experiences and social representations.info:eu-repo/semantics/publishedVersio

    Event-driven field estimation for wireless sensor networks

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    This paper introduces and analyzes a field estimation scheme for wireless sensor networks. Our scheme imitates the response of living beings to the surrounding events. The sensors define their periphery of attention based on their own readings. Readings differing from the expected behavior are considered events of interest and trigger the data transmission to the sink. The presented scheme is evaluated with real-site-collected data and the tradeoff between the amount of data sent to the sink and the reconstruction error is analyzed. Results show that signifcant reduction in the data transmission and, as a consequence, in the energy consumption of the network is achievable while keeping low the average reconstruction error.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

    Event-driven field estimation for wireless sensor networks

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    This paper introduces and analyzes a field estimation scheme for wireless sensor networks. Our scheme imitates the response of living beings to the surrounding events. The sensors define their periphery of attention based on their own readings. Readings differing from the expected behavior are considered events of interest and trigger the data transmission to the sink. The presented scheme is evaluated with real-site-collected data and the tradeoff between the amount of data sent to the sink and the reconstruction error is analyzed. Results show that signifcant reduction in the data transmission and, as a consequence, in the energy consumption of the network is achievable while keeping low the average reconstruction error.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

    Big data analyses reveal patterns and drivers of the movements of southern elephant seals

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    The growing number of large databases of animal tracking provides an opportunity for analyses of movement patterns at the scales of populations and even species. We used analytical approaches, developed to cope with big data, that require no a priori assumptions about the behaviour of the target agents, to analyse a pooled tracking dataset of 272 elephant seals (Mirounga leonina) in the Southern Ocean, that was comprised of >500,000 location estimates collected over more than a decade. Our analyses showed that the displacements of these seals were described by a truncated power law distribution across several spatial and temporal scales, with a clear signature of directed movement. This pattern was evident when analysing the aggregated tracks despite a wide diversity of individual trajectories. We also identified marine provinces that described the migratory and foraging habitats of these seals. Our analysis provides evidence for the presence of intrinsic drivers of movement, such as memory, that cannot be detected using common models of movement behaviour. These results highlight the potential for big data techniques to provide new insights into movement behaviour when applied to large datasets of animal tracking.Comment: 18 pages, 5 figures, 6 supplementary figure
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