1000 resultados para movement entrepreneurs


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We used a geolocation method based on tidal amplitude and water depth to assess the horizontal movements of 14 cod Gadus morhua equipped with time-depth recorders (TDR) in the North Sea and English Channel. Tracks ranged from 40 to 468 d and showed horizontal movements of up to 455 km and periods of continuous localised residence of up to 360 d. Cod spent time both in midwater (43% of total time) and near the seabed (57% of total time). A variety of common vertical movement patterns were seen within periods of both residence and directed horizontal movement. Hence particular patterns of vertical movement could not unequivocally define periods of migration or localised residence. After long horizontal movements, cod tended to adopt resident behaviour for several months and then return to broadly the same location where they were tagged, indicating a geospatial instinct. The results suggest that residence and homing behaviour are important features of Atlantic cod behaviour.

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Leatherback turtles Dermochelys coriacea spend most of their life in oceanic environments, whose physical and biological characteristics are primarily forged by sea current circulation. Water mass movements can mechanically act on swimming turtles, thus determining their routes, and can differentially distribute their planktonic prey. By integrating satellite tracking data with contemporaneous remote-sensing information, we analysed the post-nesting journeys of 9 leatherbacks with respect to oceanographic surface conditions. Tracked turtles showed large variations in migration routes and in final destinations, apparently without heading for specific foraging areas. Their complex tracks spread over wide regions around South Africa. Leatherbacks were greatly influenced by the currents encountered during their movements, with their trajectories displaying curves or revolutions in the presence of (and in accordance with) rotating water masses. An impressive similarity was observed between large parts of the turtle routes and those of surface drifters tracked in the same regions. Finally, leatherbacks remained associated for long periods with specific oceanographic features, which most probably offered them profitable foraging opportunities. These results agree with previous findings in showing a strong influence of oceanic currents and mesoscale features on the movements of South African leatherbacks, and additionally identify the role of current-related features in causing the observed route variability and in determining high-quality foraging hotspots for leatherbacks moving in the ocean.

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Recent advances in telemetry technology have created a wealth of tracking data available for many animal species moving over spatial scales from tens of meters to tens of thousands of kilometers. Increasingly, such data sets are being used for quantitative movement analyses aimed at extracting fundamental biological signals such as optimal searching behavior and scale-dependent foraging decisions. We show here that the location error inherent in various tracking technologies reduces the ability to detect patterns of behavior within movements. Our analyses endeavored to set out a series of initial ground rules for ecologists to help ensure that sampling noise is not misinterpreted as a real biological signal. We simulated animal movement tracks using specialized random walks known as Lévy flights at three spatial scales of investigation: 100-km, 10-km, and 1-km maximum daily step lengths. The locations generated in the simulations were then blurred using known error distributions associated with commonly applied tracking methods: the Global Positioning System (GPS), Argos polar-orbiting satellites, and light-level geolocation. Deviations from the idealized Lévy flight pattern were assessed for each track after incrementing levels of location error were applied at each spatial scale, with additional assessments of the effect of error on scale-dependent movement patterns measured using fractal mean dimension and first-passage time (FPT) analyses. The accuracy of parameter estimation (Lévy μ, fractal mean D, and variance in FPT) declined precipitously at threshold errors relative to each spatial scale. At 100-km maximum daily step lengths, error standard deviations of ≥10 km seriously eroded the biological patterns evident in the simulated tracks, with analogous thresholds at the 10-km and 1-km scales (error SD ≥ 1.3 km and 0.07 km, respectively). Temporal subsampling of the simulated tracks maintained some elements of the biological signals depending on error level and spatial scale. Failure to account for large errors relative to the scale of movement can produce substantial biases in the interpretation of movement patterns. This study provides researchers with a framework for understanding the limitations of their data and identifies how temporal subsampling can help to reduce the influence of spatial error on their conclusions.

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BACKGROUND
Fundamental movement skill (FMS) proficiency is positively associated with physical activity and fitness levels. The objective of this study was to systematically review evidence for the benefits of FMS interventions targeting youth.

METHODS
A search with no date restrictions was conducted across 7 databases. Studies included any school-, home-, or community-based intervention for typically developing youth with clear intent to improve FMS proficiency and that reported statistical analysis of FMS competence at both preintervention and at least 1 other postintervention time point. Study designs included randomized controlled trials (RCTs) using experimental and quasi-experimental designs and single group pre-post trials. Risk of bias was independently assessed by 2 reviewers.

RESULTS
Twenty-two articles (6 RCTs, 13 quasi-experimental trials, 3 pre-post trials) describing 19 interventions were included. All but 1 intervention were evaluated in primary/elementary schools. All studies reported significant intervention effects for ≥1 FMS. Meta-analyses revealed large effect sizes for overall gross motor proficiency (standardized mean difference [SMD] = 1.42, 95% confidence interval [CI] 0.68–2.16, Z = 3.77, P < .0002) and locomotor skill competency (SMD = 1.42, 95% CI 0.56–2.27, Z = 3.25, P = .001). A medium effect size for object control skill competency was observed (SMD = 0.63, 95% CI 0.28–0.98, Z = 3.53, P = .0004). Many studies scored poorly for risk of bias items.

CONCLUSIONS
School- and community-based programs that include developmentally appropriate FMS learning experiences delivered by physical education specialists or highly trained classroom teachers significantly improve FMS proficiency in youth.

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David Tittensor offers a groundbreaking new perspective on the Gülen movement, a Turkish Muslim educational activist network that emerged in the 1960s and has grown into a global empire with an estimated worth of $25 billion. Named after its leader Fethullah Gülen, the movement has established more than 1,000 secular educational institutions in over 140 countries, aiming to provide holistic education that incorporates both spirituality and the secular sciences.

Despite the movement's success, little is known about how its schools are run, or how Islam is operationalized. Drawing on thirteen months of ethnographic fieldwork in Turkey, Tittensor explores the movement's ideo-theology and how it is practiced in the schools. His interviews with both teachers and graduates from Africa, Indonesia, Central Asia, and Turkey show that the movement is a missionary organization, but of a singular kind: its goal is not simply widespread religious conversion, but a quest to recoup those Muslims who have apparently lost their way and to show non-Muslims that Muslims can embrace modernity and integrate into the wider community. Tittensor also examines the movement's operational side and shows how the schools represent an example of Mohammad Yunus's social business model: a business with a social cause at its heart.

The House of Service is an insightful exploration of one of the world's largest transnational Muslim associations, and will be invaluable for those seeking to understand how Islam will be perceived and practiced in the future.