Studies using animal models have found considerable evidence of neurological damage resulting from exposure to 3,4- methylenedioxymethamphetamine (MDMA, ecstasy). Yet, studies comparing the cognitive performance of human recreational ecstasy users to ecstasy naïve controls have produced inconsistent results. The present study is a meta-analysis of the published empirical literature on the cognitive sequelae of human recreational ecstasy use. The pooled effect size estimate for combined cognitive domains was statistically significant and moderate in size. Small to large, statistically significant aggregate effect sizes resulted for eight of the nine cognitive ability domains included in the analysis. Moderator analyses suggested that frequent ecstasy use is associated with greater cognitive impairment, cognitive impairment can occur after relatively low amounts of total lifetime cumulative use, and recovery of functioning does not occur within one year post cessation.

Human Immunodeficiency Virus (HIV) continues to disproportionately affect men who have sex with men (MSM). Gay, bisexual, and other MSM are estimated to account for two percent of the population, yet they constitute more than half of all individuals living with HIV in the United States (Centers for Disease Control [CDC], 2010). Collectively, both HIV-diagnosed (HIV-D) and HIV-nondiagnosed (HIV-ND) MSM report a variety of reasons for intentional and unintentional nonuse of condoms. Depending on partner status, HIV-D MSM are in the unique position of having the potential both to increase risk of infecting others with HIV and to expose themselves to further complication (e.g., superinfection) when they engage in unprotected anal intercourse (UAI). HIV-ND MSM are at risk of seroconversion each time they engage in UAI with an infected partner or partner of unknown HIV status. Elucidating reasons for continued engagement in UAI specific to both HIV-D and HIV-ND MSM likely is an important step in the process of effective prevention. The current study employed meta-analytic methods to evaluate HIV-risk correlates in both HIV-D and HIV-ND MSM. In addition to several individual risk correlates, within the context of the Information-Motivation-Behavioral Skills Model, Behavioral Skills variables were related to condom use in HIV-ND MSM and Motivation variables were related to condom use in both HIV-D and HIV-ND MSM. A sufficient number of studies were not available to examine Information-based risk correlates in either subgroup. Results of the present study may guide future best practice in harm reduction for both HIV-D and HIV-ND MSM

Research on the effects of downsizing has focused on several levels including the global, organization, and the individual. However, this research, at the individual level, focused specifically on the effects of downsizing on the survivors of the organization. Downsizing refers to activities undertaken by management to improve the efficiency, productivity, and competitiveness of the organization by reducing the workforce size. Many researchers explain the types of response we can expect from survivors of a corporate downsizing. The possible attitudes and behaviors due to downsizing are of particular interest to managers, because managers will inevitably face a workforce at least partially staffed with survivors of downsizing activities. The purpose of this research is to give a better understanding of the effects of downsizing on survivors. This is accomplished by systematically analyzing and combining the findings of independent studies through meta-analysis. This research investigates the variables and variable relationships which represent effects of downsizing on the survivors. The individual downsizing studies are the sources of the variables used to measure behaviors and attitudes prevalent among downsizing survivors. The results of this research give a summary of the cumulated correlations for sixteen(16) variable relationships specifying the strength, direction, and the range of the correlations. These findings enable the manager to preview, in a combined sense, a certain set of downsizing survivor responses. These results support the findings reported in the independent studies and by other downsizing researchers. The studies that did not qualify for use in the meta-analysis cumulation procedures are analyzed, through the meta-analysis vote count method, and show that the majority of the survivors had experienced negative downsizing effects. Included also is an analysis of the small sample of studies done in the public versus those done in the non-public sectors that shows no real differences, due possibly to the small sample size. This research, through the use of meta-analysis, confirms the findings of the independent studies and gives more statistical reliability and confidence to the findings. / Ph. D.

Children of today are gaining exposure to electronic reading environments at earlier ages and in greater frequencies than prior generations, as evidenced by the ubiquity of modern technologies. Such technologies provide affordances beyond basic text by supporting the screen-based rendering of aural, visual, and gestural elements. This research investigates, by way of a fixed effects meta-analysis, the overall effect of electronic reading environments on the comprehension outcomes of children between the 4th and 8th grades. Findings yielded three published studies between 2016 and 2020. Results from a total population sample of 2,125 students across the United States, showed small but significant effects of reading technology on comprehension. The implications of these findings are discussed in light of their pedagogical applications and future research directions.

Meta-analysis of 23 between-group direct observation studies of children with ADHD and typically developing peers indicates significant deficiencies in children with ADHD's ability to pay attention in classroom settings. Comparison with 59 single case design studies of children with ADHD suggests generalizability of between-group comparisons. Weighted regression analysis determined that several methodological differences – sample characteristics, diagnostic procedures, and observational coding schema – have significant effects on observed levels of attentive behavior in the classroom. Best case estimation indicates that after accounting for these factors, children with ADHD are on-task approximately 65% of the time compared to 85% for their classroom peers. Children with ADHD were also more variable in their attentive behavior across studies. Implications for conceptual models of ADHD are discussed.

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