3,715 research outputs found

    English Language Instruction, Student Engagement, and Sustainable Practices in Rural Ecuador

    Get PDF
    St. John’s University’s Vincentian Institute for Social Action aims to develop student commitment to social justice through required coursework, international travel, and community service. A strong theoretical foundation ensures that administrators and students are consistently reflecting on the dynamics of power and engaging with community members in an ethical manner. Our framework should continue conversations with the community about the value of foreign language education in their particular regional and global context and encourage students to see themselves as part of a sustainable process. Where many universities and organizations provide volunteer experiences similar in theory, we hope to improve on traditional models by supporting projects that are driven by scholarly research and community-based partnership, that in the end, effectively serve the needs of the community and its members with dignity

    Long wavelength local density of states oscillations near graphene step edges

    Full text link
    Using scanning tunneling microscopy and spectroscopy, we have studied the local density of states (LDOS) of graphene over step edges in boron nitride. Long wavelength oscillations in the LDOS are observed with maxima parallel to the step edge. Their wavelength and amplitude are controlled by the energy of the quasiparticles allowing a direct probe of the graphene dispersion relation. We also observe a faster decay of the LDOS oscillations away from the step edge than in conventional metals. This is due to the chiral nature of the Dirac fermions in graphene.Comment: 5 pages, 4 figures, to appear in Phys. Rev. Let

    SIMPLE INSTRUCTIONS ON THE CROUCH POSITION IMPROVE PERFORMANCE IN THE COUNTERMOVEMENT JUMP

    Get PDF
    The purpose of this study was to determine how simple instructions that modify the depth of countermovement lead to changes in the jump height and the biomechanical parameters related to centre of mass displacement and force application. Twenty-nine active males participated in this investigation and they performed three countermovement jumps using a self-selected crouch position, three countermovement jumps with a deeper crouch position and three countermovement jumps with a shallower crouch position in random order. The results of this study suggest that is possible to improve the jump performance in amateur competitive males with slight modification of the centre of mass displacement having the same physical condition level without any training intervention

    GAIT COORDINATION VARIABILITY BETWEEN TRAINED RUNNERS AND NON-RUNNERS

    Get PDF
    The objective of this study was to examine the differences in coordination variability in gait running between trained runners and non-runners. Kinematic data were collected from 20 participants divided into two groups (runners and non-runners) during treadmill running. Coordination variability was evaluated by calculating continuous relative phase (CRP) for four coupling pairs. The CRP variability averaged over the entire stance phase was equal between both groups of runners in the coupling joint analysed (t 0.192). The result suggest that the skill level did not influence on the CRP variability in running gait

    Confined photon modes with triangular symmetry in hexagonal microcavities in 2D photonic Crystals

    Get PDF
    We present theoretical and experimental studies of the size and thickness dependencies of the optical emission spectra from microcavities with hexagonal shape in films of two-dimensional photonic crystal. A semiclassical plane-wave model, which takes into account the electrodynamic properties of quasi-2D planar photonic microcavity, is developed to predict the eigenfrequencies of the confined photon modes as a function of both the hexagon-cavity size and the film thickness. Modes with two different symmetries, triangular and hexagonal, are critically analyzed. It is shown that the model of confined photon modes with triangular symmetry gives a better agreement between the predicted eigenmodes and the observed resonances.Comment: 14 pages, 6 figure

    Offshore aquaculture as climate change adaptation in coastal areas: sea surface temperature trends in the Western Mediterranean Sea

    Get PDF
    The warming of the Mediterranean Sea surface is currently estimated to have been 0.4°C per decade for the period 1985-2006, and the increase in water temperature may have negatively affected marine aquaculture, e.g. by decreasing productivity. Development of aquaculture without adequate planning can lead to unsustainable economic feasibility due to future climate stressors. In this sense, offshore mariculture could be an alternative for mitigating the effect of coastal warming. The purpose of this study was to evaluate the suitability of the coastline in terms of global warming and sea surface temperature trends in locations where fish aquaculture is currently being developed, as well as the spatial changes of thermal anomalies up to 30 km from the coast, during the last 31 yr in the western Mediterranean (Spanish coast). This study was conducted using EU Copernicus Marine Service Information, covering the period 1981-2018, with a spatial resolution of 4 × 4 km. The results show that, over the last decade, the Mediterranean coastal environment off the Iberian Peninsula has experienced an increase in temperature of around 1ºC due to global change, with a clear latitudinal pattern modified by mesoscale oceanographic processes. The development of offshore aquaculture at some latitudes mitigates the extreme aestival effects on surface water temperatures. Strategic plans for aquaculture development should be able to forecast and incorporate future climate projections and local oceanographic conditions, and offshore aquaculture may provide an alternative in some regions, depending on local oceanographic conditions

    An Improved Phase Filter for Differential SAR Interferometry Based on an Iterative Method

    Get PDF
    Phase quality is a key element in the analysis of the deformation of the Earth's surface carried out with differential synthetic aperture radar interferometry. Various decorrelation sources may degrade the surface deformation estimates, and thus, phase filters are needed for this kind of application. The well-known Goldstein filter is the most widely used due to its simple implementation and computational efficiency. In the past years, improved filters have been proposed, which are based on this filter but introduce variations in the data processing. The effectiveness of these filters mostly depends on the size of the filtering window, the weight of the smoothed spectrum, and the kernel used to filter the spectrum. In this paper, we evaluate the performance of four of these filters and present a new method that outperforms all of them. The proposed filter is based on an iterative method in which the original phase is denoised progressively with adaptive filtering windows of different sizes. The effectiveness of the filter is controlled by the interferometric coherence, a direct indicator of the phase quality. Moreover, we introduce some modifications regarding the processing of the power spectrum. Specifically, we propose to smooth the original phase using a new filter which is based on a Chebyshev interpolation scheme. The performance of the new filter has been tested on both simulated and real interferograms, acquired by RADARSAT-2 and the Uninhabited Aerial Vehicle Synthetic Aperture Radar, which mapped two different geological events that caused surface deformation.This work was supported in part by the Spanish Ministry of Economy, Industry and Competitiveness, in part by the State Agency of Research (AEI), in part by the European Funds for Regional Development under Project TIN2014-55413-C2-2-P and Project TEC2017-85244-C2-1-P, in part by the U.K. Natural Environmental Research Council through the Looking Inside the Continents under Grant NE/K011006/1, in part by the Rapid deployment of a seismic array in Ecuador following the April 16th 2016 M7.8 Pedernales earthquake under Grant NE/P008828/1, and in part by the Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics under Grant COMET, GA/13/M/031
    • …
    corecore