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We present the results of a numerical study comparing photometric and physical properties of simulated z= 6–9 galaxies to the observations taken by the Wide Field Camera 3 instrument aboard the Hubble Space Telescope. Using cosmological hydrodynamical simulations we find good agreement with observations in colour–colour space at all studied redshifts. We also find good agreement between observations and our Schechter luminosity function fit in the observable range, Muv≤−18, provided that a moderate dust extinction effect exists for massive galaxies. However beyond what currently can be observed, simulations predict a very large number of low‐mass galaxies and evolving steep faint‐end slopes from αL=−2.15 at z= 6 to αL=−2.64 at z= 9, with a dependence of |αL| ∝ (1 +z)0.59. During the same epoch, the normalization ϕ* increases and the characteristic magnitude becomes moderately brighter with decreasing redshift. We find similar trends for galaxy stellar mass function with evolving low‐mass end slope from αM=−2.26 at z= 6 to αM=−2.87 at z= 9, with a dependence of |αM| ∝ (1 +z)0.65. Together with our recent result on the high escape fraction of ionizing photons for low‐mass galaxies, our results suggest that the low‐mass galaxies are important contributor of ionizing photons for the reionization of the Universe at z≥ 6.

Background Telehealth technology has become more available to providers as a means of treating chronic diseases. Consideration of the applicability of telehealth technology in the treatment of schizophrenia calls for a review of the evidence base in light of the special needs and challenges in the treatment of this population. Our aims are to assess the types and nature of distant interventions for patients with schizophrenia, either telephone-based, internet-based or video-based telehealth systems. Methods The following databases—MEDLINE, PsycINFO, CINAHL, the Cochrane Library, the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, and EMBASE— were searched for the following terms alone or in combination with schizophrenia: telepsychiatry or telemedicine or telepsychology or satellite communication or remote communication. Inclusion criteria were: 1) articles dealing with telephone-, internet- or video-based interventions and 2) studies emphasizing development of an intervention, feasibility or clinical trials. Exclusions included were: 1) single case reports and 2) papers not written in English. With our search terms, we retrieved a total of 390 articles, of which 18 unique articles were relevant. Results Based on the limited data available, the use of modalities involving the telephone, internet and videoconferencing appears to be feasible in patients with schizophrenia. In addition, preliminary evidence suggests these modalities appear to improve patient outcomes. Discussion More research is needed. Investigators need to improve existing telehealth systems. In addition, researchers need to focus on developing newer interventions and determining whether these approaches can improve patient outcomes.

We present the results of a numerical study examining the effect of an H 2 -based star formation (SF) model on the rest-frame UV luminosity function and star formation rate function (SFRF) of z 6 galaxies, and the implications for reionization. Using cosmological hydrodynamical simulations outfitted with an H 2 -SF model, we find good agreement with our previous results (non-H 2 SF model) and observations at M uv −18. However, at M uv > −18, we find that the LF deviates from both our previous work and current observational extrapolations, producing significantly fewer low-luminosity galaxies and exhibiting additional turnover at the faint end. We constrain the redshift evolution of this turnover point using a modified Schechter function that includes additional terms to quantify the turnover magnitude (M t uv ) and subsequent slope (β). We find that M t uv evolves from M t uv = −17.33 (at z = 8) to −15.38 (z = 6), while β becomes shallower by Δβ = 0.22 during the same epoch. This occurs in an M uv range that will be observable by James Webb Space Telescope. By integrating the SFRF, we determine that even though the H 2 -SF model significantly reduces the number density of low-luminosity galaxies at M uv > −18, it does not suppress the total SFR density enough to affect the capability of SF to maintain reionization.

This study investigated the effects of a smoking prevention program that emphasized refusal skills training on 1730 adolescents in three high schools and six middle schools. Classes within these schools were randomly assigned to treatment or no-treatment conditions to avoid confounding schools with treatment condition. The effects of attrition on the internal and external validity of the study were examined. Although the results indicated an apparent effect of the program at the 1-year follow-up in deterring continued smoking among those who were smoking at pretest, this result may have been due to a higher rate of attrition among high-rate smokers in the treatment condition than in the control condition. Attrition also affected external validity. Across both conditions, subjects who were smoking at pretest and who were at risk to smoke were more likely to be missing at follow-up. The program did have an effect on the refusal skills of participants and the validity of this effect was not jeopardized by differential attrition.