Publications by authors named "Steven Giles"

Unlabelled: The prevalence of in youth with overweight and obesity is a global health concern, necessitating clinical interventions to treat obesity effectively through lifestyle modification. Interventions in adolescents have demonstrated improvements in healthy eating and physical activity with only modest weight loss outcomes. Consequently, there is growing interest in developing strategies to enhance the effectiveness of clinical interventions in adolescents.

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To control community transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the 2020 global pandemic, most countries implemented strategies based on direct human testing, face covering, and surface disinfection. Under the assumption that the main route of transmission includes aerosols and respiratory droplets, efforts to detect SARS-CoV-2 in fomites have focused on locations suspected of high prevalence (e.g.

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Purpose: To be effective, evidence-based programs should be delivered as prescribed. This suggests that adaptations that deviate from intervention goals may limit a program's effectiveness. This study examines the impact that number and quality of adaptations have on substance use outcomes.

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The fundamental mechanisms that control eukaryotic development include extensive regulation at the level of transcription. Gene regulatory networks, composed of transcription factors, their binding sites in DNA, and their target genes, are responsible for executing transcriptional programs. While divergence of these control networks drives species-specific gene expression that contributes to biological diversity, little is known about the mechanisms by which these networks evolve.

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We examine whether teachers' communicator style relates to student engagement, teacher-student relationships, student perceptions of teacher immediacy, as well as observer ratings of delivery skills during the implementation of All Stars, a middle school-based substance use prevention program. Data from 48 teachers who taught All Stars up to 3 consecutive years and their respective seventh-grade students (n = 2,240) indicate that having an authoritative communication style is negatively related to student engagement with the curriculum and the quality of the student-teacher relationship, while having an expressive communicator style improves teachers' immediacy to student needs. Adaptations made by a subsample of teachers (n = 27) reveal that those who were more expressive asked students more questions, used more motivational techniques, and introduced more new concepts than authoritarian teachers.

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Streptomyces sp. strain Wigar10 was isolated from a surface-sterilized garlic bulb (Allium sativum var. Purple Stripe).

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Sexual reproduction in fungi requires induction of signaling pheromones within environments that are conducive to mating. The fungus Cryptococcus neoformans is currently the fourth greatest cause of infectious death in regions of Africa and undergoes mating in phytonutrient-rich environments to create spores with infectious potential. Here we show that under conditions where sexual development is inhibited, a ∼17-fold excess of MFα pheromone transcript is synthesized and then degraded by a DEAD box protein, Vad1, resulting in low steady state transcript levels.

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Cell type specification is a fundamental process that all cells must carry out to ensure appropriate behaviors in response to environmental stimuli. In fungi, cell identity is critical for defining "sexes" known as mating types and is controlled by components of mating type (MAT) loci. MAT-encoded genes function to define sexes via two distinct paradigms: 1) by controlling transcription of components common to both sexes, or 2) by expressing specially encoded factors (pheromones and their receptors) that differ between mating types.

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PURPOSE: This study describes topics covered by coaches assisting teachers implementing a research-based drug prevention program and explores how coaching affected student outcomes. DESIGN: The All Stars drug prevention curriculum was implemented by 16 urban teachers who received four coaching sessions. Two coaches participated.

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The purpose of this study was to extend the literature in both substance use implementation and persuasive health communication by examining the extent to which students' need for cognition and impulsive decision-making moderated the relationship between teachers' classroom communication behavior and program outcomes in an evidence-based middle school substance use prevention curriculum. Participants included 48 teachers and their respective 7th grade students who participated in a randomized trial testing the effectiveness of personal coaching as a means to improve the quality with which teachers implemented the All Stars curriculum. Need for cognition and impulse decision-making were both associated with positive changes in lifestyle incongruence and commitments to not use substances for students whose teachers displayed greater interactive teaching.

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Little is known about the trajectories over time of classroom teachers' fidelity to drug prevention curricula. Using the "Concerns-Based Adoption Model" (C-BAM) as a theoretical framework, we hypothesized that teachers' fidelity would improve with repetition. Participants comprised 23 middle school teachers who videotaped their administration of three entire iterations of the All Stars curriculum.

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Homeodomain proteins function in fungi to specify cell types and control sexual development. In the meningoencephalitis-causing fungal pathogen Cryptococcus neoformans, sexual development leads to the production of spores (suspected infectious particles). Sexual development is controlled by the homeodomain transcription factors Sxi1alpha and Sxi2a, but the mechanism by which they act is unknown.

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Cryptococcus neoformans was first described as a human fungal pathogen more than a century ago. One aspect of the C. neoformans infectious life cycle that has been the subject of earnest debate is whether the spores are pathogenic.

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Objective: This study examined the association between restricting calories on intended drinking days and drunkenness frequency and alcohol-related consequences among college students.

Participants: Participants included a random sample of 4,271 undergraduate college students from 10 universities.

Methods: Students completed a Web-based survey regarding their high-risk drinking behaviors and calorie restriction on intended drinking days.

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Spores are essential particles for the survival of many organisms, both prokaryotic and eukaryotic. Among the eukaryotes, fungi have developed spores with superior resistance and dispersal properties. For the human fungal pathogens, however, relatively little is known about the role that spores play in dispersal and infection.

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The purpose of this study was to develop and validate an observation measure designed to capture teachers' use of interactive teaching skills within the delivery of the All Stars substance use prevention program. Coders counted the number of times teachers praised and encouraged students, accepted and used students' ideas, asked questions, self-disclosed personal anecdotes, and corrected student misbehavior. These teacher behaviors loaded on three factors: classroom management, acknowledgment, and student-centered methods.

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For over 3 decades, sexual development in the human fungal pathogen Cryptococcus neoformans and other fungi has been initiated by growing compatible mating partners on V8 juice medium. Although this medium is an efficient inducer of sexual development, the mechanism by which it promotes the process is unknown. To understand how V8 juice medium induces sexual development, we attempted to purify inducing factors from V8 juice, and we carried out a complete compositional analysis of V8 juice.

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Invasive aspergillosis (IA) is a common and life-threatening infection in immunocompromised individuals. A number of environmental and epidemiologic risk factors for developing IA have been identified. However, genetic factors that affect risk for developing IA have not been clearly identified.

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Oxygenated fatty acids, or oxylipins, play an essential role in physiological signaling and developmental processes in animals, plants, and fungi. Previous characterization of three Aspergillus fumigatus dioxygenases (PpoA, PpoB, and PpoC), similar in sequence to mammalian cyclooxygenases, showed that PpoA is responsible for the production of the oxylipins 8R-hydroperoxyoctadecadienoic acid and 5S,8R-dihydroxy-9Z,12Z-octadecadienoic acid and that PpoC is responsible for 10R-hydroxy-8E,12Z-hydroperoxyoctadecadienoic acid. Here, Delta ppo mutants were characterized to elucidate the role of fungal dioxygenases in A.

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Initiation of a protective immune response to infection by the pathogenic fungus Cryptococcus neoformans is mediated in part by host factors that promote interactions between immune cells and C. neoformans yeast. Surfactant protein A (SP-A) contributes positively to pulmonary host defenses against a variety of bacteria, viruses, and fungi in part by promoting the recognition and phagocytosis of these pathogens by alveolar macrophages.

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Research-based substance use prevention curricula typically yield small effects when implemented by school teachers under real-world conditions. Using a randomized controlled trial, the authors examined whether expert coaching improves the effectiveness of the All Stars prevention curriculum. Although a positive effect on students' cigarette use was noted, this finding may be attributed to marked baseline differences on this variable across the intervention and control groups.

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There is now ample evidence that teachers tend to make substantial modifications to both the prescribed content and methods of the curricula they administer, and that such modifications are likely to attenuate curricula effects. We examine the fidelity with which teachers implement "Protecting You, Protecting Me," an underage alcohol use prevention curriculum. Findings suggest that while teachers attempted to implement most sections of a lesson, the lessons taught were consistently--and often extensively--adapted.

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The function of the peroxisomes was examined in the pathogenic basidiomycete Cryptococcus neoformans. Recent studies reveal the glyoxylate pathway is required for virulence of diverse microbial pathogens of plants and animals. One exception is C.

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In the present study, we sought to elucidate the contribution of the Cryptococcus neoformans catalase gene family to antioxidant defense. We employed bioinformatics techniques to identify four members of the C. neoformans catalase gene family and created mutants lacking single or multiple catalase genes.

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