5,346 research outputs found

    Policy Barriers to School Improvement: What's Real and What's Imagined?

    Get PDF
    Some of the most promising reforms are happening where school leaders are thinking differently about how to get the strongest student outcomes from the limited resources available. But even principals who use their autonomy to aggressively reallocate resources say that persistent district, state, and federal barriers prohibit them from doing more.What are these barriers? What do they block principals from doing? Is there a way around them?CRPE researchers probed these questions with principals in three states (NH, CT, MD). These principals cited numerous district, state, and federal barriers standing in the way of school improvement. The barriers, 128 in all, fell into three categories: 1) barriers to instructional innovations, 2) barriers to allocating resources differently, and 3) barriers to improving teacher quality.Upon investigation, researchers found that principals have far more authority than they think. Only 31% of the barriers cited were "real" -- immovable statutes, policies, or managerial directives that bring the threat of real consequences if broken.The report recommends educating principals on the authority they already possess, to help them find workarounds to onerous rules. The report also outlines a number of specific state and district policy changes to grant schools the autonomy they need to improve student outcomes

    Getting Down to Dollars and Cents: What Do School Districts Spend to Deliver Student-Centered Learning?

    Get PDF
    Student-centered learning (SCL) is an approach to learning that emphasizes authentic instruction, mastery-based assessment, and engaging students in real-life experiences that take their learning beyond the school walls and school day -- all in an effort to connect students' learning to their experiences, strengths, and interests. This report offers the first detailed look into how districts and schools deal with funding issues when they adopt the SCL approach. Researchers examined district spending on SCL by comparing spending at SCL high schools to traditional high schools with similar characteristics. The researchers also performed a statistical analysis using New York City's high schools, which included 79 SCL schools. The report finds that districts don't need to spend more on these schools if they fund all schools fairly, and then allow schools to make choices about how they use their resources. The report's policy recommendations include encouraging SCL school leaders to think about spending tradeoffs to keep budgets in balance and supporting principals' efforts to secure resources from the community

    Chemiluminescent Tags for Tracking Insect Movement in Darkness: Application to Moth Photo-Orientation

    Get PDF
    The flight tracks of Manduca sexta (Lepidoptera: Sphingidae) flying toward a 5 watt incandescent light bulb were recorded under low light conditions with the aid of a camera-mounted photomultiplier and a glowing marker technique. Small felt pads bearing a chemiluminescent (glowi ma­erial, Cyalume®, were affixed to the abdomens of free-flying moths. insects orienting to a dim incandescent bulb were easily visible to the naked eye and were clearly captured on videotape. On their initial approach to the light source, M. sexta were found to orient at a mean angle of -0.220 ± 2.70 (mean ± SEM). The speed of the initial approach flight (OA ± 0.03 m/s) was significantly faster than the speed immediately after passing the light (0.29 ± 0.02 m/s; t =6.4, PM. sexta initially fly approximately at a light source and only after passing it, do they engage in circular flight around the source. M. sexta flight to lights does not entirely match any paths predicted by several light orientation mechanisms, including the commonly invoked light compass theory

    A simple nonlinear model of a generic axisymmetric wave energy converter

    Get PDF
    The aim of this work is to develop a simple nonlinear model of a wave energy converter (WEC) for capturing power from ocean waves and converting it into electrical power. A generic axisymmetric device is considered, which consists of a vertical circular cylinder surrounded by a circular annulus. The nonlinear system of equations of motion of this generic WEC are derived; these include the nonlinear term arising from viscous drag due to boundary layer separation. The expressions for radiation damping and added mass are determined by dimensional analysis. These equations are then solved numerically and the results are displayed graphically in a number of figures. Consideration of these graphs leads to conclusions that should be taken into account by the design engineer

    Optimal 2,3-Trees

    Get PDF
    The 2,3-trees that are optimal in the sense of having minimal expected number of nodes visited per access are characterized in terms of their “profiles”. The characterization leads directly to a linear-time algorithm for constructing a K-key optimal 2,3-tree for a sorted list of K keys. A number of results are derived that demonstrate how different in structure these optimal 2,3-trees are from their “average” cousins

    Associations of self-reported and device-assessed physical activity with fatigue, quality of life, and sleep quality in adults living with and beyond cancer

    Get PDF
    BACKGROUND: Greater physical activity is associated with improved outcomes in people living with and beyond cancer. However, most studies in exercise oncology use self-reported measures of physical activity. Few have explored agreement between self-reported and device-based measures of physical activity in people living with and beyond cancer. This study aimed to describe physical activity in adults affected by cancer across self-reported and device-assessed activity, to explore levels of agreement between these measures in terms of their utility for categorizing participants as meeting/not meeting physical activity guidelines, and to explore whether meeting guidelines is associated with fatigue, quality of life, and sleep quality. METHODS: A total of 1348 adults living with and beyond cancer from the Advancing Survivorship Cancer Outcomes Trial completed a survey assessing fatigue, quality of life, sleep quality, and physical activity. The Godin-Shephard Leisure-Time Physical Activity Questionnaire was used to calculate a Leisure Score Index (LSI) and an estimate of moderate-to-vigorous physical activity (MVPA). Average daily steps and weekly aerobic steps were derived from pedometers worn by participants. RESULTS: The percentage of individuals meeting physical activity guidelines was 44.3% using LSI, 49.5% using MVPA, 10.8% using average daily steps, and 28.5% using weekly aerobic steps. Agreement (Cohen's κ) between self-reported and pedometer measures ranged from 0.13 (LSI vs. average daily steps) to 0.60 (LSI vs. MVPA). After adjusting for sociodemographic and health-related covariates, meeting activity guidelines using all measures was associated with not experiencing severe fatigue (odds ratios (ORs): 1.43-1.97). Meeting guidelines using MVPA was associated with no quality-of-life issues (OR = 1.53). Meeting guidelines using both self-reported measures were associated with good sleep quality (ORs: 1.33-1.40). CONCLUSION: Less than half of all adults affected by cancer are meeting physical activity guidelines, regardless of measure. Meeting guidelines is associated with lower fatigue across all measures. Associations with quality of life and sleep differ depending on measure. Future research should consider the impact of physical activity measure on findings, and where possible, use multiple measures

    Results from the Palo Verde neutrino oscillation experiment

    Get PDF
    The ν̅e flux and spectrum have been measured at a distance of about 800 m from the reactors of the Palo Verde Nuclear Generating Station using a segmented Gd-loaded liquid scintillator detector. Correlated positron-neutron events from the reaction ν̅ep→e+n were recorded for a period of 200 d including 55 d with one of the three reactors off for refueling. Backgrounds were accounted for by making use of the reactor-on and reactor-off cycles, and also with a novel technique based on the difference between signal and background under reversal of the e+ and n portions of the events. A detailed description of the detector calibration, background subtraction, and data analysis is presented here. Results from the experiment show no evidence for neutrino oscillations. ν̅e→ν̅x oscillations were excluded at 90% C.L. for Δm2>1.12×10-3 eV2 for full mixing and sin22θ>0.21 for large Δm2. These results support the conclusion that the observed atmospheric neutrino oscillations do not involve νe
    • …
    corecore