3,256 research outputs found

    Making assessment a team sport: a qualitative study of facilitated group feedback in internal medicine residency

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    Purpose: Competency-based medical education relies on feedback from workplace-based assessment (WBA) to direct learning. Unfortunately, WBAs often lack rich narrative feedback and show bias towards Medical Expert aspects of care. Building on research examining interactive assessment approaches, the Queen’s University Internal Medicine residency program introduced a facilitated, team-based assessment initiative (“Feedback Fridays”) in July 2017, aimed at improving holistic assessment of resident performance on the inpatient medicine teaching units. In this study, we aim to explore how Feedback Fridays contributed to formative assessment of Internal Medicine residents within our current model of competency-based training. Method: A total of 53 residents participated in facilitated, biweekly group assessment sessions during the 2017 and 2018 academic year. Each session was a 30-minute facilitated assessment discussion done with one inpatient team, which included medical students, residents, and their supervising attending. Feedback from the discussion was collected, summarized, and documented in narrative form in electronic WBA forms by the program’s assessment officer for the residents. For research purposes, verbatim transcripts of feedback sessions were analyzed thematically. Results: The researchers identified four major themes for feedback: communication, intra- and inter-personal awareness, leadership and teamwork, and learning opportunities. Although feedback related to a broad range of activities, it showed strong emphasis on competencies within the intrinsic CanMEDS roles. Additionally, a clear formative focus in the feedback was another important finding. Conclusions: The introduction of facilitated team-based assessment in the Queen’s Internal Medicine program filled an important gap in WBA by providing learners with detailed feedback across all CanMEDS roles and by providing constructive recommendations for identified areas for improvement

    High-Accuracy Measurements of Total Column Water Vapor From the Orbiting Carbon Observatory-2

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    Accurate knowledge of the distribution of water vapor in Earth's atmosphere is of critical importance to both weather and climate studies. Here we report on measurements of total column water vapor (TCWV) from hyperspectral observations of near-infrared reflected sunlight over land and ocean surfaces from the Orbiting Carbon Observatory-2 (OCO-2). These measurements are an ancillary product of the retrieval algorithm used to measure atmospheric carbon dioxide concentrations, with information coming from three highly resolved spectral bands. Comparisons to high-accuracy validation data, including ground-based GPS and microwave radiometer data, demonstrate that OCO-2 TCWV measurements have maximum root-mean-square deviations of 0.9-1.3mm. Our results indicate that OCO-2 is the first space-based sensor to accurately and precisely measure the two most important greenhouse gases, water vapor and carbon dioxide, at high spatial resolution [1.3 x 2.3 km(exp. 2)] and that OCO-2 TCWV measurements may be useful in improving numerical weather predictions and reanalysis products

    Evaluation and attribution of OCO-2 XCO_2 uncertainties

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    Evaluating and attributing uncertainties in total column atmospheric CO_2 measurements (XCO_2) from the OCO-2 instrument is critical for testing hypotheses related to the underlying processes controlling XCO_2 and for developing quality flags needed to choose those measurements that are usable for carbon cycle science. Here we test the reported uncertainties of version 7 OCO-2 XCO_2 measurements by examining variations of the XCO_2 measurements and their calculated uncertainties within small regions (∼  100 km  ×  10.5 km) in which natural CO_2 variability is expected to be small relative to variations imparted by noise or interferences. Over 39 000 of these small neighborhoods comprised of approximately 190 observations per neighborhood are used for this analysis. We find that a typical ocean measurement has a precision and accuracy of 0.35 and 0.24 ppm respectively for calculated precisions larger than  ∼  0.25 ppm. These values are approximately consistent with the calculated errors of 0.33 and 0.14 ppm for the noise and interference error, assuming that the accuracy is bounded by the calculated interference error. The actual precision for ocean data becomes worse as the signal-to-noise increases or the calculated precision decreases below 0.25 ppm for reasons that are not well understood. A typical land measurement, both nadir and glint, is found to have a precision and accuracy of approximately 0.75 and 0.65 ppm respectively as compared to the calculated precision and accuracy of approximately 0.36 and 0.2 ppm. The differences in accuracy between ocean and land suggests that the accuracy of XCO2 data is likely related to interferences such as aerosols or surface albedo as they vary less over ocean than land. The accuracy as derived here is also likely a lower bound as it does not account for possible systematic biases between the regions used in this analysis

    Making assessment a team sport: a qualitative study of facilitated group feedback in internal medicine residency

    Get PDF
    Purpose: Competency-based medical education relies on feedback from workplace-based assessment (WBA) to direct learning. Unfortunately, WBAs often lack rich narrative feedback and show bias towards Medical Expert aspects of care. Building on research examining interactive assessment approaches, the Queen’s University Internal Medicine residency program introduced a facilitated, team-based assessment initiative (“Feedback Fridays”) in July 2017, aimed at improving holistic assessment of resident performance on the inpatient medicine teaching units. In this study, we aim to explore how Feedback Fridays contributed to formative assessment of Internal Medicine residents within our current model of competency-based training. Method: A total of 53 residents participated in facilitated, biweekly group assessment sessions during the 2017 and 2018 academic year. Each session was a 30-minute facilitated assessment discussion done with one inpatient team, which included medical students, residents, and their supervising attending. Feedback from the discussion was collected, summarized, and documented in narrative form in electronic WBA forms by the program’s assessment officer for the residents. For research purposes, verbatim transcripts of feedback sessions were analyzed thematically. Results: The researchers identified four major themes for feedback: communication, intra- and inter-personal awareness, leadership and teamwork, and learning opportunities. Although feedback related to a broad range of activities, it showed strong emphasis on competencies within the intrinsic CanMEDS roles. Additionally, a clear formative focus in the feedback was another important finding. Conclusions: The introduction of facilitated team-based assessment in the Queen’s Internal Medicine program filled an important gap in WBA by providing learners with detailed feedback across all CanMEDS roles and by providing constructive recommendations for identified areas for improvement

    Achieving Zero Stress in Iridium, Chromium, and Nickel Thin Films

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    We examine a method for achieving zero intrinsic stress in thin films of iridium, chromium, and nickel deposited by magnetron sputter deposition. The examination of the stress in these materials is motivated by efforts to advance the optical performance of light-weight x-ray space telescopes into the regime of sub-arc second resolution that rely on control of the film stress to values within 10-100 MPa. A characteristic feature of the intrinsic stress behavior in chromium and nickel is their sensitivity to the magnitude and sign of the intrinsic stress with argon gas pressure, including the existence of a critical pressure that results in zero film stress. This critical pressure scales linearly with the film's density. While the effect of stress reversal with argon pressure has been previously reported by Hoffman and others for nickel and chromium, we have discovered a similar behavior for iridium. Additionally, we have identified zero stress in iridium shortly after island coalescence. This feature of film growth is used for achieving a total internal stress of -2.89 MPa for a 15.8 nm thick iridium film. The surface roughness of this low-stress film was examined using scanning probe microscopy (SPM) and x-ray reflectivity (XRR) at CuK and these results presented and discussed

    Search for Light Gluinos via the Spontaneous Appearance of pi+pi- Pairs with an 800 GeV/c Proton Beam at Fermilab

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    We searched for the appearance of pi+pi- pairs with invariant mass greater than 648 MeV in a neutral beam. Such an observation could signify the decay of a long-lived light neutral particle. We find no evidence for this decay. Our null result severely constrains the existence of an R0 hadron, which is the lightest bound state of a gluon and a light gluino, and thereby also the possibility of a light gluino. Depending on the photino mass, we exclude the R0 in the mass and lifetime ranges of 1.2 -- 4.6 GeV and 2E-10 -- 7E-4 seconds, respectively. (To Appear in Phys. Rev. Lett.)Comment: Documentstyle aps,epsfig,prl (revtex), 6 pages, 7 figure

    A Measurement of the KL Charge Asymmetry

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    We present a measurement of the charge asymmetry δL\delta_L in the mode KLπ±eνK_L \to \pi^{\pm}e^{\mp}\nu based on 298 million analyzed decays. We measure a value of δL=(3322±58(stat)±47(sys))106\delta_L = (3322 \pm 58(stat) \pm 47(sys))\cdot 10^{-6}, in good agreement with previous measurements and 2.4 times more precise than the current best published result. The result is used to place more stringent limits on CPT and ΔS=ΔQ\Delta S = \Delta Q violation in the neutral kaon system.Comment: Submitted to Physical Review Letters, Dec 31, 2001. 4 pages, 4 figure

    Search for the Decay Kl -> pi0 e+ e-

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    We report on a search for the decay Kl -> pi0 e+ e- carried out by the KTeV/E799 experiment at Fermilab. This decay is expected to have a significant CP violating contribution and the measurement of its branching ratio could support the CKM mechanism for CP violation or could point to new physics. Two events were observed in the 1997 data with an expected background of 1.06 +-0.41 events, and we set an upper limit Br(Kl -> pi0 e+ e-) < 5.1 x 10^-10 at the 90% confidence level.Comment: 13 pages, 2 figure

    Orbiting Carbon Observatory-2 (OCO-2) cloud screening algorithms: validation against collocated MODIS and CALIOP data

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    The objective of the National Aeronautics and Space Administration's (NASA) Orbiting Carbon Observatory-2 (OCO-2) mission is to retrieve the column-averaged carbon dioxide (CO₂) dry air mole fraction (XCO2) from satellite measurements of reflected sunlight in the near-infrared. These estimates can be biased by clouds and aerosols, i.e., contamination, within the instrument's field of view. Screening of the most contaminated soundings minimizes unnecessary calls to the computationally expensive Level 2 (L2) X_(CO₂) retrieval algorithm. Hence, robust cloud screening methods have been an important focus of the OCO-2 algorithm development team. Two distinct, computationally inexpensive cloud screening algorithms have been developed for this application. The A-Band Preprocessor (ABP) retrieves the surface pressure using measurements in the 0.76 µm O₂ A band, neglecting scattering by clouds and aerosols, which introduce photon path-length differences that can cause large deviations between the expected and retrieved surface pressure. The Iterative Maximum A Posteriori (IMAP) Differential Optical Absorption Spectroscopy (DOAS) Preprocessor (IDP) retrieves independent estimates of the CO₂ and H₂O column abundances using observations taken at 1.61 µm (weak CO₂ band) and 2.06 µm (strong CO₂ band), while neglecting atmospheric scattering. The CO₂ and H₂O column abundances retrieved in these two spectral regions differ significantly in the presence of cloud and scattering aerosols. The combination of these two algorithms, which are sensitive to different features in the spectra, provides the basis for cloud screening of the OCO-2 data set. To validate the OCO-2 cloud screening approach, collocated measurements from NASA's Moderate Resolution Imaging Spectrometer (MODIS), aboard the Aqua platform, were compared to results from the two OCO-2 cloud screening algorithms. With tuning of algorithmic threshold parameters that allows for processing of  ≃ 20–25 % of all OCO-2 soundings, agreement between the OCO-2 and MODIS cloud screening methods is found to be  ≃ 85 % over four 16-day orbit repeat cycles in both the winter (December) and spring (April–May) for OCO-2 nadir-land, glint-land and glint-water observations. No major, systematic, spatial or temporal dependencies were found, although slight differences in the seasonal data sets do exist and validation is more problematic with increasing solar zenith angle and when surfaces are covered in snow and ice and have complex topography. To further analyze the performance of the cloud screening algorithms, an initial comparison of OCO-2 observations was made to collocated measurements from the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) aboard the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). These comparisons highlight the strength of the OCO-2 cloud screening algorithms in identifying high, thin clouds but suggest some difficulty in identifying some clouds near the surface, even when the optical thicknesses are greater than 1

    Search for the Decay KLπ0μ+μK_L \to \pi^0 \mu^+ \mu^-

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    We report on a search for the decay \klpimumu carried out as a part of the KTeV experiment at Fermilab. This decay is expected to have a significant CPCP violating contribution and a direct measurement will either support the CKM mechanism for CP violation or point to new physics. Two events were observed in the 1997 data with an expected background of 0.87±0.150.87 \pm 0.15 events, and we set an upper limit \BR{\klpimumu} <3.8×1010 <3.8 \times 10^{-10} at the 90% confidence level.Comment: See also "Observation of the Decay KLμ+μγγK_L\to \mu^+\mu^- \gamma \gamma", also by the KTeV collaboratio
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