Introduction: Caffeine is a psychostimulant possessing arousal, motor activation, and reinforcing properties, which is consumed daily by most adolescents aged 12-19 years. Although current understanding of the implications of adolescent caffeine consumption for school behaviors remains incomplete, studies have shown that in addition to acute effects of the drug, in common with other habit-forming psychoactive substances, regular use leads to physical dependence, evidenced by recurring negative withdrawal symptoms.
Methods: Employing two waves of longitudinal data, we tested the prospective association between daily caffeine use and homeroom teacher-observed self-control and problem behavior in a sample of middle-school students in 20 schools in West Virginia in the United States.
Background: The school climate concept has been promising, but has long-standing critiques that have not been adequately addressed to date. The School as a Protective Factor approach represents one attempt to offer a new approach that builds on and extends beyond the concept of school climate while addressing previously identified limitations.
Contributions To Theory: The School as a Protective Factor approach offers a new framework for conceptualizing, measuring, and establishing protective school social and learning environments that co-promote academic achievement and student health in schools, especially student mental health and substance use/abuse prevention.
Background: The conceptual framework for School as a Protective Factor approach was presented in a companion article in this issue of the journal. The current article describes the validation of the School as a Protective Factor-Brief (SPF-Brief), a 13-item survey measuring the 3 core constructs and 13 defining characteristics of this framework.
Methods: The SPF-Brief was validated through 2 studies.
The Icelandic Prevention Model (IPM) follows a systematic but flexible process of community capacity building, data collection, analysis, dissemination, and community-engaged decision-making to guide the data-informed selection, prioritization, and implementation of intervention strategies in preventing adolescent substance use. This paper describes two new evaluation tools intended to assess the: 1) integrity of IPM implementation, and 2) unique aspects of IPM implementation in different community contexts. These evaluation tools include a: 1) five-phase IPM Evaluation Framework for Assessing Value Across Communities, Cultures, and Outcomes (IPM-EF); and 2) 10-Step IPM Implementation Integrity and Consistency Assessment (IPM-IICA) that utilizes both quantitative (scored) and qualitative (narrative) data elements to characterize implementation integrity and consistency at both community coalition and school community levels.
View Article and Find Full Text PDFDetecting introgression between closely related populations or species is a fundamental objective in evolutionary biology. Existing methods for detecting migration and inferring migration rates from population genetic data often assume a neutral model of evolution. Growing evidence of the pervasive impact of selection on large portions of the genome across diverse taxa suggests that this assumption is unrealistic in most empirical systems.
View Article and Find Full Text PDFMachine learning has increasingly been applied to a wide range of questions in phylogenetic inference. Supervised machine learning approaches that rely on simulated training data have been used to infer tree topologies and branch lengths, to select substitution models, and to perform downstream inferences of introgression and diversification. Here, we review how researchers have used several promising machine learning approaches to make phylogenetic inferences.
View Article and Find Full Text PDFExperiments were conducted over a 3-yr period to evaluate the effects of bacterial inoculants on the fermentation profile and aerobic stability of whole-plant corn silage (WPC), snaplage (SNA), and high-moisture corn (HMC). Whole-plant corn was inoculated with Lentilactobacillus buchneri PJB1 in combination with Lactiplantibacillus plantarum MTD1 or with Lpb. plantarum alone (experiments 1 and 2).
View Article and Find Full Text PDFMotivation: The application of machine learning approaches in phylogenetics has been impeded by the vast model space associated with inference. Supervised machine learning approaches require data from across this space to train models. Because of this, previous approaches have typically been limited to inferring relationships among unrooted quartets of taxa, where there are only three possible topologies.
View Article and Find Full Text PDFUnderstanding the processes that generate and maintain biodiversity at and below the species level is a central goal of evolutionary biology. Here we explore the spatial and temporal drivers of diversification of the treefrog subgroup Dendropsophus rubicundulus, a subgroup of the D. microcephalus species group, over periods of pronounced geological and climatic changes in the Neotropical savannas that they inhabit.
View Article and Find Full Text PDFAbstractMembers of the sea anemone genus are abundant in temperate rocky habitats and fouling communities. Their biogeographic history is expected to reflect changes in currents and habitats that have influenced benthic communities, such as the climate-influenced changes that occurred during the Last Glacial Maximum. More recently, however, anthropogenic influences such as shipping transportation and the creation of artificial habitat have altered and affected the composition of modern-day marine communities.
View Article and Find Full Text PDFBackground: Preventing nicotine use onset among children and youth is an important public health goal. One possible contributor that has received little empirical investigation is caffeine use. The goal of this study was to examine the possible contribution of caffeine to nicotine onset during early adolescence.
View Article and Find Full Text PDFBackground: Young people who experience higher levels of social support from their schools and families have been shown to be less likely to develop symptoms of negative mental health outcomes such as depression and anxiety. This raises questions concerning how young people's stress and psychological changes due to the COVID-19 pandemic as well as social support during this time have affected their overall mental health. The aim of this study was to assess the association between sources of parental- and school-level social support and youth perceptions of COVID-19-related emotional impact on mental health among early adolescent girls and boys in Appalachia.
View Article and Find Full Text PDFPreventing or delaying the onset of alcohol use among children and youth is an important public health goal. One possible factor in alcohol use onset among early adolescents is caffeine. The aim of this study was to assess the possible contribution of caffeine to the onset of alcohol use during early adolescence.
View Article and Find Full Text PDFBackground: Alcohol use impairs psychosocial and neurocognitive development and increases the vulnerability of youth to academic failure, substance use disorders, and other mental health problems. The early onset of alcohol use in adolescents is of particular concern, forecasting substance abuse in later adolescence and adulthood. To date, evidence suggests that youth in rural areas are especially vulnerable to contextual and community factors that contribute to the early onset of alcohol use.
View Article and Find Full Text PDFBayesian skyline plots (BSPs) are a useful tool for making inferences about demographic history. For example, researchers typically apply BSPs to test hypotheses regarding how climate changes have influenced intraspecific genetic diversity over time. Like any method, BSP has assumptions that may be violated in some empirical systems (e.
View Article and Find Full Text PDFPleistocene glacial cycles drastically changed the distributions of taxa endemic to temperate rainforests in the Pacific Northwest, with many experiencing reduced habitat suitability during glacial periods. In this study, we investigate whether glacial cycles promoted intraspecific divergence and whether subsequent range changes led to secondary contact and gene flow. For seven invertebrate species endemic to the PNW, we estimated species distribution models (SDMs) and projected them onto current and historical climate conditions to assess how habitat suitability changed during glacial cycles.
View Article and Find Full Text PDFTraditionally, single-copy orthologs have been the gold standard in phylogenomics. Most phylogenomic studies identify putative single-copy orthologs using clustering approaches and retain families with a single sequence per species. This limits the amount of data available by excluding larger families.
View Article and Find Full Text PDFBackground: The major greenhouse gas from ruminants is enteric methane (CH) which in 2010, was estimated at 2.1 Gt of CO equivalent, accounting for 4.3% of global anthropogenic greenhouse gas emissions.
View Article and Find Full Text PDFThe disjunct temperate rainforests of the Pacific Northwest of North America (PNW) are characterized by late-successional dominant tree species Thuja plicata (western redcedar) and Tsuga heterophylla (western hemlock). The demographic histories of these species, along with the PNW rainforest ecosystem in its entirety, have been heavily impacted by geological and climatic changes the PNW has experienced over the last 5 million years, including mountain orogeny and repeated Pleistocene glaciations. These environmental events have ultimately shaped the history of these species, with inland populations potentially being extirpated during the Pleistocene glaciations.
View Article and Find Full Text PDFPhylogenetics has long relied on the use of orthologs, or genes related through speciation events, to infer species relationships. However, identifying orthologs is difficult because gene duplication can obscure relationships among genes. Researchers have been particularly concerned with the insidious effects of pseudoorthologs-duplicated genes that are mistaken for orthologs because they are present in a single copy in each sampled species.
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