406 research outputs found

    Explorer 12 observations of charged particles in the inner radiation zone

    Get PDF
    Explorer XII satellite observations of charged particles in inner radiation zon

    Correlated satellite measurements of low-energy electron precipitation and ground based observations of a visible auroral arc

    Get PDF
    Comparison of Injun 5 satellite measurements of low energy electron precipitation and ground based observations of visible auroral ar

    Observations of charged particle precipitation over the auroral zone during a magnetic substorm

    Get PDF
    An array of sensitive electrostatic analyzers was launched on the satellite INJUN 5 into a nearly polar, low altitude orbit. A series of three traversals of the northern auroral zone in the local evening sector on 3 December 1968 has provided high energy- and time-resolution observations of low-energy proton and electron intensities within the energy range 50 smaller than E smaller than 15,000 eV before, during and after a polar magnetic substorm. The region of high intensities of plasma-sheet electrons expanded dramatically during the substorm, extending 3.5 deg farther poleward and approximately 4.5 deg farther equatorward relative to that of the preceding pass

    Electron precipitation in the post midnight sector of the auroral zones

    Get PDF
    Comprehensive measurements of the angular distributions and energy spectra of electron intensities with electrostatic analyzer arrays on board the low-altitude satellite Injun 5 are reported. These are for the post-midnight sector of the auroral zones during the high-intensity events accompanying magnetic substorms. Precipitation features on closed terrestrial field lines well equatorward of the trapping boundary for energetic electrons with E greater than 45 keV were examined. No evidences of maxima in the differential energy spectra or of strongly field-aligned currents which are indicative of quasi-static electric fields aligned parallel to the geomagnetic field were found. Precipitation of low-energy electron intensities fluctuated on time scales greater than 2 seconds as viewed at the satellite position. This precipitation was characterized by isotropy for all pitch angles outside the atmospheric backscatter cone

    Breakout Session: Increasing Study Recruitment and Retention: Working with Communities to Use Social Media

    Get PDF
    Overview: Social media and research: What are the options? -- Ethical considerations -- Gateway to Community-Based Participatory Research. Conclusion: Social media has the potential to improve the methods and scope of community research. A number of technical and ethical issues remain unresolved

    Race, Ethnicity, Language, Social Class, and Health Communication Inequalities: A Nationally-Representative Cross-Sectional Study

    Get PDF
    BACKGROUND: While mass media communications can be an important source of health information, there are substantial social disparities in health knowledge that may be related to media use. The purpose of this study is to investigate how the use of cancer-related health communications is patterned by race, ethnicity, language, and social class. METHODOLOGY/PRINCIPAL FINDINGS: In a nationally-representative cross-sectional telephone survey, 5,187 U.S. adults provided information about demographic characteristics, cancer information seeking, and attention to and trust in health information from television, radio, newspaper, magazines, and the Internet. Cancer information seeking was lowest among Spanish-speaking Hispanics (odds ratio: 0.42; 95% confidence interval: 0.28-0.63) compared to non-Hispanic whites. Spanish-speaking Hispanics were more likely than non-Hispanic whites to pay attention to (odds ratio: 3.10; 95% confidence interval: 2.07-4.66) and trust (odds ratio: 2.61; 95% confidence interval: 1.53-4.47) health messages from the radio. Non-Hispanic blacks were more likely than non-Hispanic whites to pay attention to (odds ratio: 2.39; 95% confidence interval: 1.88-3.04) and trust (odds ratio: 2.16; 95% confidence interval: 1.61-2.90) health messages on television. Those who were college graduates tended to pay more attention to health information from newspapers (odds ratio: 1.98; 95% confidence interval: 1.42-2.75), magazines (odds ratio: 1.86; 95% confidence interval: 1.32-2.60), and the Internet (odds ratio: 4.74; 95% confidence interval: 2.70-8.31) and had less trust in cancer-related health information from television (odds ratio: 0.44; 95% confidence interval: 0.32-0.62) and radio (odds ratio: 0.54; 95% confidence interval: 0.34-0.86) compared to those who were not high school graduates. CONCLUSIONS/SIGNIFICANCE: Health media use is patterned by race, ethnicity, language and social class. Providing greater access to and enhancing the quality of health media by taking into account factors associated with social determinants may contribute to addressing social disparities in health

    Plasmas in Saturn's magnetosphere

    Get PDF
    The solar wind plasma analyzer on board Pioneer 2 provides first observations of low-energy positive ions in the magnetosphere of Saturn. Measurable intensities of ions within the energy-per-unit charge (E/Q) range 100 eV to 8 keV are present over the planetocentric radial distance range about 4 to 16 R sub S in the dayside magnetosphere. The plasmas are found to be rigidly corotating with the planet out to distances of at least 10 R sub S. At radial distances beyond 10 R sub S, the bulk flows appear to be in the corotation direction but with lesser speeds than those expected from rigid corotation. At radial distances beyond the orbit of Rhea at 8.8 R sub S, the dominant ions are most likely protons and the corresponding typical densities and temperatures are 0.5/cu cm and 1,000,000 K, respectively, with substantial fluctuations. It is concluded that the most likely source of these plasmas in the photodissociation of water frost on the surface of the ring material with subsequent ionization of the products and radially outward diffusion. The presence of this plasma torus is expected to have a large influence on the dynamics of Saturn's magnetosphere since the pressure ratio beta of these plasmas approaches unity at radial distances as close to the planet as 6.5 R sub S. On the basis of these observational evidences it is anticipated that quasi-periodic outward flows of plasma, accompanied with a reconfiguration of the magnetosphere beyond about 6.5 R sub S, will occur in the local night sector in order to relieve the plasma pressure from accretion of plasma from the rings

    Attitudes of a Multiethnic Group of Immigrants towards Online Social Networking and Physical Activity: Results from Focus Group Discussions

    Get PDF
    Background and Purpose: Sedentary behavior contributes to the risk of obesity and cardiovascular disease. Increasing physical activity is particularly important for new immigrants to the U.S., since the risk of obesity and cardiovascular disease increases with acculturation to U.S. society. This study examined facilitators and barriers of using social media to provide information on physical activity, perceptions of the benefits of physical activity, and barriers to physical activity in low English proficiency immigrants in a New England city. Methods: Three focus groups were conducted to collect information from 25 adults in a New England city (Mean= 47.7+13.2 year, 68% female, 64% Asian). Results: Participants reported using social media to connect with family and friends, rather than to make new social connections. Barriers to social media use included access and privacy concerns. While the participants believed physical activity was necessary for health, they identified a number of barriers to exercise, including lack of access to exercise facilities, financial issues, and information on safe and effective ways to exercise. Conclusion: Using social media may be a convenient way to provide information about physical activity to low English proficiency immigrants, but researchers need to address the barriers to utilizing social media and engaging in physical activity
    • …
    corecore