A latent growth curve model to estimate electronic screen use patterns amongst adolescents aged 10 to 17 years

Background: High quality, longitudinal data describing young people's screen use across a number of distinct forms of screen activity is missing from the literature. This study tracked multiple screen use activities (passive screen use, gaming, social networking, web searching) amongst 10- to 17-year-old adolescents across 24 months. Methods: This study tracked the screen use of 1948 Australian students in Grade 5 (n = 636), Grade 7 (n = 672), and Grade 9 (n = 640) for 24 months. At approximately six-month intervals, students reported their total screen time as well as time spent on social networking, passive screen use, gaming, and web use. Patterns of screen use were determined using latent growth curve modelling. Results: In the Grades 7 and 9 cohorts, girls generally reported more screen use than boys (by approximately one hour a day), though all cohorts of boys reported more gaming. The different forms of screen use were remarkably stable, though specific cohorts showed change for certain forms of screen activity. Conclusion: These results highlight the diverse nature of adolescent screen use and emphasise the need to consider both grade and sex in future research and policy

Parental Acceptanceâ\u80\u93Rejection and Adolescent Maladjustment: Mothersâ\u80\u99 and Fathersâ\u80\u99 Combined Roles

In this study we examined the relationship between adolescent reports of paternal and maternal acceptance–rejection and adolescent maladjustment to test the hypothesis that inter-parental inconsistency was a specific risk factor for maladjustment. The participants were 2624 adolescents (1316 boys) aged between 10 and 16 years. Perceived maternal and paternal acceptance–rejection—defined in terms of the framework of interpersonal acceptance–rejection theory—and anxiety–depression symptoms and aggressive behaviors were assessed. The intraclass correlation coefficients were performed to evaluate the impact of inter-parental inconsistency on adolescent adjustment. Moreover, a cluster analysis was used to uncover patterns in combinations of maternal and paternal acceptance–rejection. Our findings show that, in general, adolescents perceive their mothers and fathers as similarly accepting or rejecting. Parental rejection was associated with adolescent maladjustment. Inter-parental inconsistency in acceptance–rejection was also associated with maladaptive symptoms and behaviors. Living in a non-intact family amplified the effects of rejection and inter-parental inconsistency. Effects of parental rejection are observed also during adolescence; both parents are equally influential and even one rejecting parent is risk factor for adolescent maladjustment

Improving the oral bioavailability of beneficial polyphenols through designed synergies

A substantial and growing consumer demand exists for plant-based functional foods that improve general health and wellbeing. Amongst consumed phytochemicals, the polyphenolic compounds tend to be the most bioactive. Many commonly consumed polyphenols have been shown to have specific and potent health-promoting activities when assessed by high-throughput in vitro assays and when administered to experimental animals by injection. However, very few have been shown to have any beneficial effects in animals or man when orally consumed, because of the poor bioavailability exhibited by most polyphenols following the ingestion. Consumed polyphenols, like most pharmaceuticals, are regarded as xenobiotics by the body and must overcome many barriers, including extensive enzymatic and chemical modification during digestion and absorption, to reach their site(s) of action. This is especially true for polyphenols targeting the brain, which is protected by the tightly regulated blood–brain barrier. Interestingly, many polyphenols are also known to specifically modify some of the metabolic and transport processes that govern bioavailability. Therefore, the opportunity exists to increase the bioactivity of beneficial polyphenols by designing specific synergistic interactions with polyphenols that improve their oral bioavailability. This hypothesis and review paper will discuss some of the endogenous systems that limit the bioavailability of ingested polyphenols to the body and the brain, and the means by which bioavailability may be improved by specifically designing synergies between orally consumed polyphenols