A Case Study of Eukaryogenesis: The Evolution of Photoreception by Photolyase/Cryptochrome Proteins.

Eukaryogenesis, the origin of the eukaryotes, is still poorly understood. Herein, we show how a detailed all-kingdom phylogenetic analysis overlaid with a map of key biochemical features can provide valuable clues. The photolyase/cryptochrome family of proteins are well known to repair DNA in response to potentially harmful effects of sunlight and to entrain circadian rhythms. Phylogenetic analysis of photolyase/cryptochrome protein sequences from a wide range of prokaryotes and eukaryotes points to a number of horizontal gene transfer events between ancestral bacteria and ancestral eukaryotes. Previous experimental research has characterised patterns of tryptophan residues in these proteins that are important for photoreception, specifically a tryptophan dyad, a canonical tryptophan triad, an alternative tryptophan triad, a tryptophan tetrad and an alternative tetrad. Our results suggest that the spread of the different triad and tetrad motifs across the kingdoms of life accompanied the putative horizontal gene transfers and is consistent with multiple bacterial contributions to eukaryogenesis.

Parental Messages about Substance Use in Early Adolescence: Extending a Model of Drug-Talk Styles.

This study extends a typology of parent-offspring drug talk styles to early adolescents and investigates associations with adolescent substance use. Data come from a self-report survey associated with a school-based, 7th grade drug prevention curriculum. Mixed methods were used to collect data across four measurement occasions spanning 30 months. Findings highlight the frequencies of various drug-talk styles over time (i.e., situated direct, ongoing direct, situated indirect, ongoing indirect, never talked), messages adolescents hear from parents, and comparisons of alcohol, cigarette, and marijuana use by drug-talk style. This study advances an understanding of parent-adolescent communication about substances and holds practical implications for drug prevention efforts.

Adherence and delivery: implementation quality and program outcomes for the seventh-grade keepin' it REAL program.

Poor implementation quality (IQ) is known to reduce program effects making it important to consider IQ for evaluation and dissemination of prevention programs. However, less is known about the ways specific implementation variables relate to outcomes. In this study, two versions of keepin' it REAL, a seventh-grade drug prevention intervention, were implemented in 78 classrooms in 25 schools in rural districts in Pennsylvania and Ohio. IQ was measured through observational coding of 276 videos. IQ variables included adherence to the curriculum, teacher engagement (attentiveness, enthusiasm, seriousness, clarity, positivity), student engagement (attention, participation), and a global rating of teacher delivery quality. Factor analysis showed that teacher engagement, student engagement, and delivery quality formed one factor, which was labeled delivery. A second factor was adherence to the curriculum. Self-report student surveys measured substance use, norms (beliefs about prevalence and acceptability of use), and efficacy (beliefs about one's ability to refuse substance offers) at two waves (pretest, immediate posttest). Mixed model regression analysis which accounted for missing data and controlled for pretest levels examined implementation quality's effects on individual level outcomes, statistically controlling for cluster level effects. Results show that when implemented well, students show positive outcomes compared to students receiving a poorly implemented program. Delivery significantly influenced substance use and norms, but not efficacy. Adherence marginally significantly predicted use and significantly predicted norms, but not efficacy. Findings underscore the importance of comprehensively measuring and accounting for IQ, particularly delivery, when evaluating prevention interventions.

Random assignment of schools to groups in the drug resistance strategies rural project: some new methodological twists.

Random assignment to groups is the foundation for scientifically rigorous clinical trials. But assignment is challenging in group randomized trials when only a few units (schools) are assigned to each condition. In the DRSR project, we assigned 39 rural Pennsylvania and Ohio schools to three conditions (rural, classic, control). But even with 13 schools per condition, achieving pretest equivalence on important variables is not guaranteed. We collected data on six important school-level variables: rurality, number of grades in the school, enrollment per grade, percent white, percent receiving free/assisted lunch, and test scores. Key to our procedure was the inclusion of school-level drug use data, available for a subset of the schools. Also, key was that we handled the partial data with modern missing data techniques. We chose to create one composite stratifying variable based on the seven school-level variables available. Principal components analysis with the seven variables yielded two factors, which were averaged to form the composite inflate-suppress (CIS) score which was the basis of stratification. The CIS score was broken into three strata within each state; schools were assigned at random to the three program conditions from within each stratum, within each state. Results showed that program group membership was unrelated to the CIS score, the two factors making up the CIS score, and the seven items making up the factors. Program group membership was not significantly related to pretest measures of drug use (alcohol, cigarettes, marijuana, chewing tobacco; smallest p > .15), thus verifying that pretest equivalence was achieved.

Unpacking the Effect of Parental Monitoring on Early Adolescent Problem Behavior: Mediation by Parental Knowledge and Moderation by Parent-Youth Warmth.

This study explores the monitoring process longitudinally among a sample of rural early adolescents and addresses two research questions (1) Does maternal knowledge mediate the relationship between three aspects of the parental monitoring process and adolescent problem behavior: active parent monitoring efforts, youth disclosure, and parental supervision? (2) Are these meditational pathways moderated by the affective quality of the parent-child relationship? Parent efforts to monitor youth and youth disclosure in the Fall of Grade 6 predicted substance use and delinquency in Grade 8. These relations were mediated by increases in maternal knowledge assessed in the Spring of Grade 6, suggesting that the protective effects of these constructs are partially indirect. Supervision was not significantly related to maternal knowledge or problem behavior. Parent efforts to monitor were more strongly related to maternal knowledge in families with high levels of positive affect than in families with low levels of positive affect.

From kids, through kids, to kids: examining the social influence strategies used by adolescents to promote prevention among peers.

Recent technological advances have increased the interest and ability of lay audiences to create messages; however, the feasibility of incorporating lay multimedia messages into health campaigns has seldom been examined. Drawing on the principle of cultural grounding and narrative engagement theory, this article seeks to examine what types of messages adolescents believe are most effective in persuading their peers to resist substance use and to provide empirical data on the extent to which audience-generated intervention messages are consistent with the associated campaign philosophy and branding. Data for the current study are prevention messages created by students as part of a four-lesson substance use prevention "booster" program delivered to eighth-grade students in 20 rural schools in Pennsylvania and Ohio during 2010-2011. Content analysis results indicate that didactic message strategies were more common in audience-generated messages than narrative strategies, although strategy was somewhat dependent on the medium used. Two of the most common strategies that adolescents used to persuade peers not to use substances were negative consequences and identity appeals, and messages varied in the degree to which they were consistent with the theoretical underpinnings and program philosophy of the prevention campaign. Implications of the current study for understanding the social construction of substance use prevention messages among adolescents and incorporating audience-generated messages in health communication campaigns are discussed.

Describing teacher-student interactions: a qualitative assessment of teacher implementation of the 7th grade keepin' it REAL substance use intervention.

Variations in the delivery of school-based substance use prevention curricula affect students' acquisition of the lesson content and program outcomes. Although adaptation is sometimes viewed as a lack of fidelity, it is unclear what types of variations actually occur in the classroom. This observational study investigated teacher and student behaviors during implementation of a middle school-based drug prevention curriculum in 25 schools across two Midwestern states. Trained observers coded videos of 276 lessons, reflecting a total of 31 predominantly Caucasian teachers (10 males and 21 females) in 73 different classes. Employing qualitative coding procedures, the study provides a working typology of implementation patterns based on varying levels of teacher control and student participation. These patterns are fairly consistent across lessons and across classes of students, suggesting a teacher-driven delivery model where teachers create a set of constraints within which students vary their engagement. Findings provide a descriptive basis grounded in observation of classroom implementation that can be used to test models of implementation fidelity and quality as well as impact training and other dissemination research.

Adapting school-based substance use prevention curriculum through cultural grounding: a review and exemplar of adaptation processes for rural schools.

A central challenge facing twenty-first century community-based researchers and prevention scientists is curriculum adaptation processes. While early prevention efforts sought to develop effective programs, taking programs to scale implies that they will be adapted, especially as programs are implemented with populations other than those with whom they were developed or tested. The principle of cultural grounding, which argues that health message adaptation should be informed by knowledge of the target population and by cultural insiders, provides a theoretical rational for cultural regrounding and presents an illustrative case of methods used to reground the keepin' it REAL substance use prevention curriculum for a rural adolescent population. We argue that adaptation processes like those presented should be incorporated into the design and dissemination of prevention interventions.

Parental support and monitoring influences on adolescent alcohol use: A peer selection mediation model.

Previous studies on parental support have consistently shown it predicts lower adolescent alcohol use. Yet findings regarding the influence of parental monitoring have been mixed. The current study aims to resolve this concern while examining peer selection as a mediator of both parenting factors. The current study used structural equation modeling and bootstrapping mediation analysis on data from 3,027 youth across three waves of the Adolescent Alcohol Prevention Trial to examine these factors. We tested a latent path model where the effect of parental support and monitoring in 7th grade on adolescent alcohol use in 9th grade was hypothesized to be mediated by best friends' alcohol use in 8th grade. Results: Higher parental support in seventh grade predicted lower adolescent alcohol use in 9th grade, mediated by lower best friends' use in eighth grade (ab = -0.025, CI = [-0.152, -0.003]). Yet parental monitoring in seventh grade did not predict alcohol use in 9th grade when parental support was included as a co-predictor in the model (ab = 0.018, CI = -0.135 - 0.025). There was also no significant mediation effect for the monitoring to youth drinking path. Adolescent's closeness with their parents may direct them to choose non-drinking friends, which leads to lower alcohol use in high school. Previously suggested effects of parental monitoring may be accounted for by support from parents.

Perceptions of smoking prevalence by youth in countries with and without a tobacco advertising ban.

This study examined a proposed mechanism by which exposure to cigarette advertising may mediate the subsequent smoking of youth. We hypothesized that children's exposure to cigarette advertising leads them to overestimate the prevalence of smoking, and that these distorted perceptions, in turn, lead to increased intentions to smoke. Children in Finland, where there has been a total tobacco advertising ban since 1978, were compared with children in the United States at a time when tobacco advertising was ubiquitous. Samples of 477 8- to 14-year-old Helsinki students and 453 8- to 14-year-old Los Angeles students whose lifetime cigarette use consisted of no more than a puff of a cigarette were administered questionnaires in their classrooms. The primary hypothesis was confirmed. Los Angeles youth were significantly more likely than Helsinki youth to overestimate the prevalence of adult smoking, in spite of the fact that actual adult smoking prevalence in Helsinki was almost twice that of Los Angeles adults. A similar, significant pattern for perceived peer smoking was obtained, with Los Angeles youth being more likely than Helsinki youth to overestimate prevalence, in spite of the actual greater prevalence of youth smoking in Helsinki.

Making the Most of It: Application of Planned Missingness Design to Increase the Efficiency of Diagnostic Assessment.

Multimethod assessment is recommended as "best practice" in clinical assessment and is often implemented through the combined use of symptom rating scales and structured interviews. While this approach increases confidence in the validity of assessment, it also increases burden, expense, and leads to the accumulation of redundant information. To address this problem, we evaluate the use a planned missingness design within the framework of adult Attention Deficit/Hyperactivity Disorder (ADHD) assessment. In a sample of 169 young adults, we fit a two-method measurement (TMM) model using ADHD symptoms obtained from rating scales and a structured diagnostic interview. Based on an estimated 8:1 differential between the cost of conducting an in-person diagnostic interview vs. completing questionnaires online, we conducted a series of Monte Carlo simulations to determine the utility of combining TMM with a planned missingness design. We find that even when costs are kept constant, statistical power of the TMM/planned missingness design was equal to the power that would have been obtained had nearly twice the number of participants with complete data been recruited. Conversely, costs could be decreased by 20-25%, while maintaining statistical power equivalent to a design with complete data. Our results suggest the TMM design is a promising technique for reducing the cost and burden of diagnostic assessment within research settings.

Associations between maternal closeness, suicidal ideation, and risk behaviors in Cape Town.

Health compromising behaviors, such as smoking and other risk behaviors tend to co-occur, and contribute to the leading causes of preventable death, disease, and disability among adolescents and young adults worldwide. The present study assesses a model of the direct and indirect effects of maternal closeness with suicidal ideation on smoking and risky behaviors. The sample consisted of 657 South African youth assessed over two time points with comparison of effects between males and females. Maternal closeness had a significant effect on suicidal ideation among females. Suicidal ideation had a significant effect on risky behaviors among males and lifetime smoking among females. A significant indirect effect was observed from maternal closeness to lifetime smoking among females. These results indicate that suicidal ideation is associated with lifetime smoking and risky behaviors separately among male and female adolescents and highlight the need to focus on the development of mental health preventive interventions for both genders.

Design and analysis of the Community Youth Development Study longitudinal cohort sample.

Communities That Care (CTC) is a prevention system designed to reduce adolescent substance use and delinquency through the selection of effective preventive interventions tailored to a community's specific profile of risk and protection. A community-randomized trial of CTC, the Community Youth Development Study, is currently being conducted in 24 communities across the United States. This article describes the rationale, multilevel analyses, and baseline comparability for the study's longitudinal cohort design. The cohort sample consists of 4,407 fifth- and sixth-grade students recruited in 2004 and 2005 and surveyed annually through ninth grade. Results of mixed-model ANOVAs indicated that students in CTC and control communities exhibited no significant differences (ps > .05) in baseline levels of student outcomes.