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The Social Norms Approach is a widely used intervention strategy for promoting positive health-related behaviors. The Approach operates on the premise that individuals misperceive their peers’ behaviors and attitudes, with evidence of under- and over-estimations of behaviors and peer approval for a range of positive and negative behaviors respectively. The greater these misperceptions, the more likely an individual is to engage in negative behaviors such as consuming heavier amounts of alcohol and other substances and reduce positive behaviors such as eating healthily and using sun protection. However, there are many complexities associated with the use of social norms feedback in interventions and empirical studies. Many social norms interventions do not attempt to change misperceptions of social norms or measure changes in normative perceptions pre- and post-intervention. This has led to a conflation of generic social norms interventions with those that are explicitly testing the Approach’s assumptions that it is misperceptions of peer norms which drive behavior. The aim of the present review was to provide a critical appraisal of the use of the Social Norms Approach as an intervention strategy for health-related behaviors, identify the current issues with its evidence base, highlight key opportunities and challenges facing the approach, and make recommendations for good practice when using the approach. There are three core challenges and areas for improved practice when using the Social Norms Approach. Firstly, improvements in the methodological rigor and clarity of reporting of ‘social norms’ research, ensuring that studies are testing the approach’s assumption of the role of misperceptions on behaviors are differentiated from studies investigating other forms of ‘social norms.’ Secondly, the need for a more explicit, unified and testable theoretical model outlining the development of normative misperceptions which can be translated into interventional studies. Finally, a need for a more robust evaluation of social norms interventions in addition to randomized controlled trials, such as the inclusion of process evaluations, qualitative studies of participant experiences of social norms feedback, and alternative study designs better suited for real-world public health settings. Such improvements are required to ensure that the Social Norms Approach is adequately tested and evaluated.

We present observations of 136 RS CVn active binary systems obtained with the ROSAT Position Sensitive Proportional Counter (PSPC) during the All-Sky Survey phase of the mission. Of this sample, 112 targets were detected in exposures of ~600 s or less. This represents the largest sample of RS CVn systems observed to date at any wavelength, including X-rays. Furthermore, since the entire sky was surveyed, these data do not suffer from any biases other than those present in the methods used to discover the RS CVn binaries. A maximum value of FV/Fboi ~ 10" 3 , where F x is the surface flux, is found with no apparent dependence on (B-V) color. This is consistent with the hypothesis that there is a maximum ("saturated") coronal heating rate for the most active and rapidly rotating stars. No correlation between L x and L hol is evident in the data. We observe a decrease in surface flux with increasing period for the entire sample, but this trend results from the giants and subgiants since for dwarfs the surface fluxes are independent of rotation period. For the evolved stars, the flux-period relation results from the strong correlation of period and stellar radius. No dependence of X-ray emission on t> rot , orbital separation or the Roche lobe filling fraction is observed. We demonstrate that the secondary does not affect the activity level of the system other than inducing, and maintaining, rapid rotation in the active star. Except for dwarfs, the rotation period provides the best stellar or orbital parameter to predict the X-ray surface flux level. Comparison of the X-ray properties of the RS CVn systems with 6 cm radio and C rv ultraviolet emission is also presented.

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We analyze Goddard High-Resolution Spectrograph data to infer the properties of local interstellar gas and the deuterium/hydrogen (D/H) ratio for lines of sight toward four nearby late-type starsÈHR 1099, 31 Comae, b Ceti, and b Cassiopeiae. The data consist of spectra of the hydrogen and deuterium Lya lines, and echelle spectra of the Mg II h and k lines toward all stars except b Cas. Spectra of the RS CVnÈtype spectroscopic binary system HR 1099 were obtained near opposite quadratures to determine the intrinsic stellar emission line proÐle and the interstellar absorption separately. Multiple-velocity components were found toward HR 1099 and b Cet. The spectra of 31 Com and b Cet are particularly interesting because they sample lines of sight toward the north and south Galactic poles, respectively, for which H I and D I column densities were not previously available.The north Galactic pole appears to be a region of low hydrogen density like the "" interstellar tunnel ÏÏ toward v CMa. The temperature and turbulent velocities of the local interstellar medium (LISM) that we measure for the lines of sight toward HR 1099, 31 Com, b Cet, and b Cas are similar to previously measured values (T B 7000 K and m \ 1.0È1.6 km s~1). The deuterium/hydrogen ratios found for these lines of sight are also consistent with previous measurements of other short lines of sight, which suggest D/H B 1.6 ] 10~5. In contrast, the Mg abundance measured for the b Cet line of sight [implying a logarithmic depletion of D(Mg) \ ]0.30^0.15] is about 5 times larger than the Mg abundance previously observed toward a Cen, and about 20 times larger than all other previous measurements for the LISM. These results demonstrate that metal abundances in the LISM vary greatly over distances of only a few parsecs.