3,704 research outputs found

    A scoping review of social determinants of health curricula in post-graduate medical education

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    Social determinants of health are responsible for 50% of ill health. The Royal College of Physicians and Surgeons of Canada CanMEDS role of “physician advocate” requires physicians to attain competency in this particular domain, but physician trainees feel this is not well covered in their training programs. This study performed a scoping review of social determinants of health curricula that had been described, implemented and evaluated in post-graduate medical education. A search using MEDLINE(OvidSP) database, with search terms “residency,” ”curriculum,” and “social determinants” with no age, language, and publication date restrictions was done.Researchers identified a total of 12 studies, all from the United States, in internal medicine (n=4), pediatrics (n=4), family medicine (n=2), or multiple (n=2) residency programs. Most curricula (n=8, 67%), were longitudinal, and most contained both patient or community exposure (n=11, 92%) and/or classroom-based components (n=10, 83%). Most (78%) curricula improved participant related outcomes, including exam performance, awareness regarding personal practice, confidence, improved screening for social determinants of health and referral to support services. Program specific outcomes were frequently positive (50%) and included resident satisfaction and high course evaluation scores, high representation of resident and faculty from minority groups, applicability of training to underserviced populations, and improved engagement of marginalized community members. When evaluated, academic outcomes were always positive, and included acceptance of scholarly projects to national conferences, publication of research work, grants earned to support health projects, local or national awards for leadership and community engagement, and curriculum graduates later pursuing related Masters degrees and/or establishing medical practices in underserved areas. Only one study reported a patient-related outcome, with advice provided by health care providers considered by patients to be helpful. Researchers used these results to design recommendations for creation of a post-graduate curriculum to address social determinants of health were provided

    Coherence-Induced Bias Reduction in Synthetic Aperture Sonar Along-Track Micronavigation

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    Subwavelength motion estimation is vital for the production of focused synthetic aperture sonar (SAS) imagery. The required precision is obtainable from the sonar data itself through a process termed micronavigation. Along-track micronavigation is achieved by a similar technique to that used in correlation velocity logs (CVLs), where sparse estimates of the spatial coherence function are interpolated to estimate the location of the peak coherence and hence estimate the interping vehicle motion. However, along-track micronavigation estimates made using this technique are biased, which limits the utility of these measurements for long-term navigation of autonomous underwater vehicles (AUVs). Three sources of along-track motion estimation bias are considered in this article. First, imperfect temporal registration between the signals results in coherence estimates that are negatively biased as a function of the temporal offset. Second, the sparse estimates of the spatial coherence function are obtained by cross-correlation of complex baseband signals, a process which is known to result in positively biased coherence estimates, especially when the true coherence is low. Finally, mismatches between the underlying spatial coherence function and the interpolation kernel used to estimate the peak coherence location also result in along-track micronavigation bias. In this article, we describe and evaluate three methods for reducing along-track micronavigation bias. We introduce a temporal registration of the signals before coherence estimation, which reduces the impact of negative coherence bias due to temporal offsets. The remaining coherence estimation bias is reduced by combining multiple coherence estimates in a Bayesian coherence estimator. Additionally, an improved interpolation kernel is derived with a significantly improved fit compared to the current gold standard Gaussian interpolation kernel. The improvements in along-track micronavigation accuracy are demonstrated using two simulated data sets, which both allow comparison with ground truth. The first involves direct simulation of the spatial coherence from a given interping geometry using the pulse-echo formulation of the van Cittert-Zernike theorem, while the second involves simulation of raw sonar echo data using a point-scatterer model. Using these simulations, a reduction in along-track micronavigation bias of 48.5%-99.5% is demonstrated, with reductions in along-track micronavigation error standard deviation of up to 34%. This improvement expands the potential for SAS-equipped AUVs to reduce their long-term navigation drift, facilitating longer underwater transits, improved target localization, and reduced track misalignment in repeat-pass operations.</p

    Two perspectives on rebooting computer music education: Composition and computer science

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    Laptop ensembles and orchestras, in addition to being hubs for collectives of experimental musicians, have become a popular feature in music technology tertiary education curricula. The (short) history of such groups reveals tensions in what these groups are for, and where they fit within their enfolding institutions. Are the members programmers, composers, or performers? Should laptop ensemble courses focus on performance practice, composition, or digital synthesis? Should they be anarchic or hierarchical? Eschewing potential answers, we instead pose a new question: what happens when computer science students and music students are jumbled together in the same group? In this paper, we discuss what a laptop ensemble might have to offer both groups of students and describe the results of our experiments in running joint laptop ensemble courses. We conclude with questions that motivate further iterations of our laptop ensemble as a promising site of computer music education in a modern university environment

    The impact of drought on carers

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    Carers have, on average, a more tenuous and weaker attachment to the labour market than non-carers because they face a complex set of demands on their time and must balance the needs of other people. Accordingly, it is plausible that regional shocks from droughts may adversely affect carers compared to other residents. This paper combines meteorological data with recent census data to illustrate that drought in agricultural labour markets has a greater impact on employment outcomes for carers than other residents. Furthermore, the employment differential is not manifest for part-time employment outcomes. Implications for policy makers are considered in some detail

    Japan: State and People in the Twentieth Century - Papers presented at the STICERD 20th Anniversary Symposium in July 1998

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    The four papers and comments in this volume deal with different aspects of the relationship between state and people in twentieth century Japan. Ben-Ami Shillony's paper is concerned with religious aspects of this relationship, in particular concerning the role of the emperor, while Barbara Molony is concerned with the position of women. Sheldon Garon's paper deals with the state's propaganda to promote saving, while Werner Pascha addresses the broader issue of the position of central government and the possibility of Japan's moving towards more of a federal structure.Japan, religion, emperor, women, saving, federalism

    Model-based 3D micro-navigation and bathymetry estimation for interferometric synthetic aperture sonar

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    Sub-wavelength navigation information is vital for the formation of all synthetic aperture sonar (SAS) data products. This challenging requirement can be achieved using the redundant phase centre (RPC) or displaced phase centre antenna (DPCA) micro-navigation algorithm, which uses cross-correlation of signals with inter-ping coherence to estimate time delays and hence make navigation estimates. In this paper a new approach to micro- navigation for interferometric synthetic aperture sonar is introduced. The algorithm makes 3D vehicle position estimates for each sonar ping by making use of time delays measured between all possible pairs of redundant phase centre arrays, using both interferometric arrays on each side of the vehicle. Simultaneous estimation of coarse bathymetry allows the SAS images to be projected onto ground-range. The method is based on non-linear minimization of the difference in modelled and measured time delays and surges between redundant phase centre arrays. The approach is demonstrated using data collected by the CMRE MUSCLE AUV using its 270-330 kHz SAS during the MANEX’14 experiment. SAS images have been projected onto the coarsely estimated bathymetry, and interferograms have been formed. The coarse bathymetry estimate and vehicle navigation estimate are validated by the quality of the image focussing and the near-zero phase of the interferogram. The method has the potential to improve through-the-sensor navigation aiding and to increase the accuracy of single-pass bathymetry estimation. Future development of the algorithm for repeat-pass operation has the potential to enable repeat-pass track registration in three dimensions. The method is therefore an important step towards improved coherent change detection and high resolution bathymetry estimation

    Terahertz electron-hole recollisions in GaAs/AlGaAs quantum wells: robustness to scattering by optical phonons and thermal fluctuations

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    Electron-hole recollisions are induced by resonantly injecting excitons with a near-IR laser at frequency fNIRf_{\text{NIR}} into quantum wells driven by a ~10 kV/cm field oscillating at fTHz=0.57f_{\text{THz}} = 0.57 THz. At T=12T=12 K, up to 18 sidebands are observed at frequencies fsideband=fNIR+2nfTHzf_{\text{sideband}}=f_{\text{NIR}}+2n f_{\text{THz}}, with 82n28-8 \le 2n \le 28. Electrons and holes recollide with total kinetic energies up to 57 meV, well above the ELO=36E_{\text{LO}} = 36 meV threshold for longitudinal optical (LO) phonon emission. Sidebands with order up to 2n=222n=22 persist up to room temperature. A simple model shows that LO phonon scattering suppresses but does not eliminate sidebands associated with kinetic energies above ELOE_{\text{LO}}.Comment: 5 pages, 4 figure

    Phase wrap error correction by random sample consensus with application to synthetic aperture sonar micro-navigation

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    Accurate time delay estimation between signals is crucial for coherent imaging systems such as synthetic aperture sonar (SAS) and synthetic aperture radar (SAR). In such systems, time delay estimates resulting from the cross-correlation of complex signals are commonly used to generate navigation and scene height measurements. In the presence of noise, the time delay estimates can be ambiguous, containing errors corresponding to an integer number of phase wraps. These ambiguities cause navigation and bathymetry errors and reduce the quality of synthetic aperture imagery. In this article, an algorithm is introduced for the detection and correction of phase wrap errors. The random sample consensus (RANSAC) algorithm is used to fit 1-D and 2-D models to the ambiguous time delay estimates made in the time delay estimation step of redundant phase center (RPC) micronavigation. Phase wrap errors are then corrected by recalculating the phase wrap number using the best-fitting model. The approach is demonstrated using the data collected by the 270&amp;#x2013;330 kHz SAS of the NATO Centre for Maritime Research and Experimentation Minehunting unmanned underwater vehicle for Shallow water Covert Littoral Expeditions. Systems with lower fractional bandwidth were emulated by windowing the bandwidth of the signals to increase the occurrence of phase wrap errors. The time delay estimates were refined using both the RANSAC algorithms using 1-D and 2-D models and the commonly used branch-cuts method. Following qualitative assessment of the smoothness of the full-bandwidth time delay estimates after application of these three methods, the results from the 2-D RANSAC method were chosen as the reference time delay estimates. Comparison with the reference estimates shows that the 1-D and 2-D RANSAC methods outperform the branch-cuts method, with improvements of 29&amp;#x0025;&amp;#x2013;125&amp;#x0025; and 30&amp;#x0025;&amp;#x2013;150&amp;#x0025;, respectively, compared to 16&amp;#x0025;&amp;#x2013;134&amp;#x0025; for the branch-cuts method for this data set.</p

    Phase wrap error correction by random sample consensus with application to synthetic aperture sonar micro-navigation

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    Accurate time delay estimation between signals is crucial for coherent imaging systems such as synthetic aperture sonar (SAS) and synthetic aperture radar (SAR). In such systems, time delay estimates resulting from the cross-correlation of complex signals are commonly used to generate navigation and scene height measurements. In the presence of noise, the time delay estimates can be ambiguous, containing errors corresponding to an integer number of phase wraps. These ambiguities cause navigation and bathymetry errors and reduce the quality of synthetic aperture imagery. In this article, an algorithm is introduced for the detection and correction of phase wrap errors. The random sample consensus (RANSAC) algorithm is used to fit 1-D and 2-D models to the ambiguous time delay estimates made in the time delay estimation step of redundant phase center (RPC) micronavigation. Phase wrap errors are then corrected by recalculating the phase wrap number using the best-fitting model. The approach is demonstrated using the data collected by the 270&amp;#x2013;330 kHz SAS of the NATO Centre for Maritime Research and Experimentation Minehunting unmanned underwater vehicle for Shallow water Covert Littoral Expeditions. Systems with lower fractional bandwidth were emulated by windowing the bandwidth of the signals to increase the occurrence of phase wrap errors. The time delay estimates were refined using both the RANSAC algorithms using 1-D and 2-D models and the commonly used branch-cuts method. Following qualitative assessment of the smoothness of the full-bandwidth time delay estimates after application of these three methods, the results from the 2-D RANSAC method were chosen as the reference time delay estimates. Comparison with the reference estimates shows that the 1-D and 2-D RANSAC methods outperform the branch-cuts method, with improvements of 29&amp;#x0025;&amp;#x2013;125&amp;#x0025; and 30&amp;#x0025;&amp;#x2013;150&amp;#x0025;, respectively, compared to 16&amp;#x0025;&amp;#x2013;134&amp;#x0025; for the branch-cuts method for this data set.</p
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