Time trends and predictors of initiation for cigarette and waterpipe smoking among Jordanian school children: Irbid, 2008-2011

Smoking prevalence among adolescents in the Middle East remains high while rates of smoking have been declining among adolescents elsewhere. The aims of this research were to (1) describe patterns of cigarette and waterpipe (WP) smoking, (2) identify determinants of WP smoking initiation, and (3) identify determinants of cigarette smoking initiation in a cohort of Jordanian school children. ^ Among this cohort of school children in Irbid, Jordan, (age ≈ 12.6 at baseline) the first aim (N=1,781) described time trends in smoking behavior, age at initiation, and changes in frequency of smoking from 2008–2011 (grades 7–10). The second aim (N=1,243) identified determinants of WP initiation among WP-naïve students; and the third aim (N=1,454) identified determinants of cigarette smoking initiation among cigarette naïve participants. Determinants of initiation were assessed with generalized mixed models. All analyses were stratified by gender. ^ Baseline prevalence of current smoking (cigarettes or WP) for boys and girls was 22.9% and 8.7% respectively. Prevalence of ever- and current- any smoking, cigarette smoking, WP smoking, and dual cigarette/WP smoking was higher in boys than girls each year (p<0.001). At all time points, prevalence of WP smoking was higher than that of cigarette smoking (p<0.001) for both boys and girls. WP initiation was documented in 39% of boys and 28% of girls. Cigarette initiation was documented in 37% of boys and 24% of girls. Determinants of WP initiation included ever-cigarette smoking, low WP refusal self-efficacy, intention to smoke, and having teachers and friends who smoke WP. Determinants of cigarette smoking initiation included ever-WP smoking, low cigarette refusal self-efficacy, intention to start smoking cigarettes, and having friends and family who smoke.^ These studies reveal intensive smoking patterns at early ages among Jordanian youth in Irbid, characterized by a predominance of WP smoking. WP may be a vehicle for tobacco dependence and subsequent cigarette uptake. The sizeable incidence of WP and cigarette initiation among students of both sexes points to a need for culturally relevant smoking prevention interventions. Gender-specific factors, refusal skills, and smoking cessation of both WP and cigarettes for youth and their parents/teachers would be important components of such initiatives. ^

Mediational effects in cognitive behavioral treatment for anxiety disorders in children and adolescents

The current study examined whether variables that have been found to influence treatment outcome serve as mediators of a child and adolescent cognitive behavioral treatment (CBT) anxiety program at multiple time points throughout the intervention. The study also examined mediating variables measured at multiple time points during treatment to determine the time lags necessary for changes in the mediator variable to translate into changes on treatment gains. Participants were 168 youth (ages 6 to 16 years; 54% males) and their mothers who presented to the Child Anxiety and Phobia Program (CAPP) at Florida International University (FIU). Overall, results indicate that the mediators at multiple time points influenced youth anxiety in a fluctuating manner, such that a decrease in skills at one given session caused changes in youth anxiety at a later session. This dynamic between the mediator and outcome may be reflective of the process of therapeutic change and suggests that skills gained from session to session took time to exert their effect on youth anxiety. The methodology employed helps to elucidate how variables mediate treatment outcome in youth anxiety disorders.

An examination of the effects of a summer book-reading program on the language and early literacy outcomes of toddlers from high risk environments

The current study examined the impact of an early summer literacy program and the mediating effects of the home literacy environment on the language and literacy outcomes of a group of children at-risk for long-term developmental and academic delays. Participating children (n=54) were exposed to an intensive book-reading intervention each summer (June through mid August) over a 3-year period. The current study implemented an ex post facto, quasi-experimental design. This nonequivalent group design involved a pretest and posttest over three time points for a non-randomized treatment group and a matched non-treatment comparison group. Results indicated that literacy scores did improve for the children over the 3-year period; however, language scores did not experience the same rate of change over time. Receptive language was significantly impacted by attendance, and race/ethnicity. Expressive language was impacted significantly by gestational age and attendance. Results also indicated that language outcomes for young children who are exposed to a literacy program were higher than those who did not participate; however, only receptive language yielded significance at the p<.05 level. These study results also found that activities in the home that support literacy and learning do indeed impact language and literacy outcomes for these children, specifically, the age at which a child is read to, the number of books in the home, a child’s enjoyment of reading, and whether a child looks at books on his or her own impact language scores. This study concluded that at-risk young children do benefit from center-based literacy intervention. This literacy experience, however, is also driven by the children's home environment, their attendance to the program, whether they were premature or not and the type of caregiver.

Phylogenetic analysis of within -host serially-sampled viral data

The primary goal of this dissertation is the study of patterns of viral evolution inferred from serially-sampled sequence data, i.e., sequence data obtained from strains isolated at consecutive time points from a single patient or host. RNA viral populations have an extremely high genetic variability, largely due to their astronomical population sizes within host systems, high replication rate, and short generation time. It is this aspect of their evolution that demands special attention and a different approach when studying the evolutionary relationships of serially-sampled sequence data. New methods that analyze serially-sampled data were developed shortly after a groundbreaking HIV-1 study of several patients from which viruses were isolated at recurring intervals over a period of 10 or more years. These methods assume a tree-like evolutionary model, while many RNA viruses have the capacity to exchange genetic material with one another using a process called recombination. ^ A genealogy involving recombination is best described by a network structure. A more general approach was implemented in a new computational tool, Sliding MinPD, one that is mindful of the sampling times of the input sequences and that reconstructs the viral evolutionary relationships in the form of a network structure with implicit representations of recombination events. The underlying network organization reveals unique patterns of viral evolution and could help explain the emergence of disease-associated mutants and drug-resistant strains, with implications for patient prognosis and treatment strategies. In order to comprehensively test the developed methods and to carry out comparison studies with other methods, synthetic data sets are critical. Therefore, appropriate sequence generators were also developed to simulate the evolution of serially-sampled recombinant viruses, new and more through evaluation criteria for recombination detection methods were established, and three major comparison studies were performed. The newly developed tools were also applied to "real" HIV-1 sequence data and it was shown that the results represented within an evolutionary network structure can be interpreted in biologically meaningful ways. ^

Aspects Allogenic Memory in the Gorgonian Coral Swiftia Exserta

Accelerated graft rejection can be used to determine immune memory in the gorgonian coral swiftia exserta. The extent ofthe persistence of immune memory will be determined in this experiment using replicate sets that are time elapsed from 1, 3, and 6 month. Although corals lack circulatory systems which can be a component of adaptive systemic immunity, this study will attempt to determine whether this gorgonian coral is capable of transmitting immune information throughout its colonial body. Results showed that at each of the time points; one, three, and six months the secondary response group and the primary response group were significantly different (at p=0.001) therefore, demonstrating long term immune memory. While the primary response group and the 3rd party specificity response group were similar, both were significantly different (at p=O. 001) from the secondary response group which shows the response to be specific, with memory applicable to the original antigen. Systemic immunity was not determined to be present for 15 em and one week after initial sensitization.