19,073 research outputs found

    Mission design for a ballistic slow flyby Comet Encke 1980

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    Preliminary mission analyses for a proposed 1980 slow flyby (7-9 km/s) of comet Encke are presented. Among the topics covered are science objectives, Encke's physical activity and ephemeris accuracy, trajectory and launch-window analysis, terminal guidance, and spacecraft concepts. The nominal mission plan calls for a near-perihelion intercept with two spacecraft launched on a single launch vehicle. Both spacecraft will arrive at the same time, one passing within 500 km from Encke's nucleus on its sunward side, the other cutting through the tail region. By applying a small propulsive correction about three weeks after the encounter, it is possible to retarget both spacecraft for a second Encke intercept in 1984. The potential science return from the ballistic slow flyby is compared with other proposed mission modes for the 1980 Encke flyby mission, including the widely advocated slow flyby using solar-electric propulsion. It is shown that the ballistic slow flyby is superior in every respect

    Are food exposures obtained through commercial market panels representative of the general population? Implications for outbreak investigations

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    Current methods of control recruitment for case-control studies can be slow (a particular issue for outbreak investigations), resource-intensive and subject to a range of biases. Commercial market panels are a potential source of rapidly recruited controls. Our study evaluated food exposure data from these panel controls, compared with an established reference dataset. Market panel data were collected from two companies using retrospective internet-based surveys; these were compared with reference data from the National Diet and Nutrition Survey (NDNS). We used logistic regression to calculate adjusted odds ratios to compare exposure to each of the 71 food items between the market panel and NDNS participants. We compared 2103 panel controls with 2696 reference participants. Adjusted for socio-demographic factors, exposure to 90% of foods was statistically different between both panels and the reference data. However, these differences were likely to be of limited practical importance for 89% of Panel A foods and 79% of Panel B foods. Market panel food exposures were comparable with reference data for common food exposures but more likely to be different for uncommon exposures. This approach should be considered for outbreak investigation, in conjunction with other considerations such as population at risk, timeliness of response and study resources

    Bioprocesses

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    The application of remote sensing techniques to the study of eutrophication in natural waters and the location and characterization of fronts is considered. The specific problem to be studied is examined along with the feasibility and capabability of remote sensing techniques for each application

    Electron microscopic observation on dolichos enation mosaic virus

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    RESP-573

    Sports medicine in Hawaii: care of the high school athlete in Oahu's public schools.

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    A recent study by the National Athletic Trainers Association indicated that injuries occur more often during practice than during games in high school athletics. Results of the 3-year study indicated that 60% of basketball injuries occurred in boys and young men during practice and 59% occurred in women. About 2/3 of the estimated 120,000 injuries suffered by prep wrestlers each year happen during practice. The study found that an average of 331,865 high school football players (1/3 of the million who play football each year) were sidelined by an injury at least once. With these statistics in mind, our study looks at the approach to the management of injury in the public schools that make up the Oahu Inter-scholastic Association (OIA) in the state of Hawaii. The estimated number of student athletes that participate in organized athletics in the OIA is 7,960 and the number of coaches is 1,189
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