Changing Attitudes and Facilitating Understanding in the Undergraduate Statistics Classroom: A Collaborative Learning Approach

Collaborative and problem-based learning strategies are theorized to be effective methods for strengthening undergraduate science, technology, engineering, and mathematics education. Peer-Led Team Learning (PLTL) is a collaborative learning technique that engages students in problem solving and discussion under the guidance of a trained peer facilitator. This comparative study investigates the impact of a PLTL-based learning community program on both content mastery and dispositions of undergraduate students taking an introductory course in applied statistics. Results suggest that students participating in the learning community program acquired significantly greater content mastery in statistics when compared to non-participating peers. Moreover, the learning community experience may provide students with a buffer against developing the negative attitudes and perceptions that often pervade the undergraduate applied statistics classroom

Assessing the Impact of a Multi-Disciplinary Peer-Led-Team Learning Program on Undergraduate STEM Education

There has been a national call to transition away from the traditional, passive, lecture-based model of STEM education towards one that facilitates learning through active engagement and problem solving. This mixed-methods research study examines the impact of a supplemental Peer-Led Team Learning (PLTL) program on knowledge and skill acquisition for students in introductory biology, chemistry, calculus and applied statistics courses. Results indicate program participants reliably outperform their matched pairs in courses that emphasize quantitative reasoning. Moreover, program participants report acquiring important insights about learning, collaboration, and engagement in undergraduate STEM education. These results are consistent with previous findings on PLTL and also provide insight into the roles of course context and student population on program outcomes

Changing attitudes and facilitating understanding in the undergraduate statistics classroom: A collaborative learning approach

Collaborative and problem-based learning strategies are theorized to be effective methods for strengthening undergraduate science, technology, engineering, and mathematics education. Peer-Led Team Learning (PLTL) is a collaborative learning technique that engages students in problem solving and discussion under the guidance of a trained peer facilitator. This comparative study investigates the impact of a PLTL-based learning community program on both content mastery and dispositions of undergraduate students taking an introductory course in applied statistics. Results suggest that students participating in the learning community program acquired significantly greater content mastery in statistics when compared to non-participating peers. Moreover, the learning community experience may provide students with a buffer against developing the negative attitudes and perceptions that often pervade the undergraduate applied statistics classroom

Genetic Diversity of Potassium Ion Channel Proteins Encoded by Chloroviruses That Infect Chlorella heliozoae

Chloroviruses are large, plaque-forming, dsDNA viruses that infect chlorella-like green algae that live in a symbiotic relationship with protists. Chloroviruses have genomes from 290 to 370 kb, and they encode as many as 400 proteins. One interesting feature of chloroviruses is that they encode a potassium ion (K+) channel protein named Kcv. The Kcv protein encoded by SAG chlorovirus ATCV-1 is one of the smallest known functional K+ channel proteins consisting of 82 amino acids. The KcvATCV-1 protein has similarities to the family of two transmembrane domain K+ channel proteins; it consists of two transmembrane -helixes with a pore region in the middle, making it an ideal model for studying K+ channels. To assess their genetic diversity, kcv genes were sequenced from 103 geographically distinct SAG chlorovirus isolates. Of the 103 kcv genes, there were 42 unique DNA sequences that translated into 26 new Kcv channels. The new predicted Kcv proteins differed from KcvATCV-1 by 1 to 55 amino acids. The most conserved region of the Kcv protein was the filter, the turret and the pore helix were fairly well conserved, and the outer and the inner transmembrane domains of the protein were the most variable. Two of the new predicted channels were shown to be functional K+ channels

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Detecting the impact of temperature on transmission of Zika, dengue, and chikungunya using mechanistic models

Recent epidemics of Zika, dengue, and chikungunya have heightened the need to understand the seasonal and geographic range of transmission by Aedes aegypti and Ae. albopictus mosquitoes. We use mechanistic transmission models to derive predictions for how the probability and magnitude of transmission for Zika, chikungunya, and dengue change with mean temperature, and we show that these predictions are well matched by human case data. Across all three viruses, models and human case data both show that transmission occurs between 18–34°C with maximal transmission occurring in a range from 26–29°C. Controlling for population size and two socioeconomic factors, temperature-dependent transmission based on our mechanistic model is an important predictor of human transmission occurrence and incidence. Risk maps indicate that tropical and subtropical regions are suitable for extended seasonal or year-round transmission, but transmission in temperate areas is limited to at most three months per year even if vectors are present. Such brief transmission windows limit the likelihood of major epidemics following disease introduction in temperate zones

Assessing the Impact of a Multi-Disciplinary Peer-Led-Team Learning Program on Undergraduate STEM Education

There has been a national call to transition away from the traditional, passive, lecture-based model of STEM education towards one that facilitates learning through active engagement and problem solving. This mixed-methods research study examines the impact of a supplemental Peer-Led Team Learning (PLTL) program on knowledge and skill acquisition for students in introductory biology, chemistry, calculus and applied statistics courses. Results indicate program participants reliably outperform their matched pairs in courses that emphasize quantitative reasoning. Moreover, program participants report acquiring important insights about learning, collaboration, and engagement in undergraduate STEM education. These results are consistent with previous findings on PLTL and also provide insight into the roles of course context and student population on program outcomes

A pilot study evaluating a one-session attention modification training to decrease overeating in obese children.

There are a number of neurocognitive and behavioral mechanisms that contribute to overeating and obesity, including an attentional bias to food cues. Attention modification programs, which implicitly train attention away from specific cues, have been used in anxiety and substance abuse, and could logically be applied to food cues. The purpose of this study was to evaluate the initial efficacy of a single session attention modification training for food cues (AMP) on overeating in overweight and obese children. Twenty-four obese children who eat in the absence of hunger participated in two visits and were assigned to an attention modification program (AMP) or attentional control program (ACC). The AMP program trained attention away 100% of the time from food words to neutral words. The ACC program trained attention 50% of the time to neutral and 50% of the time to food. Outcome measures included the eating in the absence of hunger free access session, and measures of craving, liking and salivation. Results revealed significant treatment effects for EAH percent and EAH kcal (group by time interactions p&lt;.05). Children in the ACC condition showed a significant increase over time in the number of calories consumed in the free access session (within group t=3.09, p=.009) as well as the percent of daily caloric needs consumed in free access (within group t=3.37, p=.006), whereas children in the AMP group demonstrated slight decreases in these variables (within group t=-0.75 and -0.63, respectively). There was a trend suggesting a beneficial effect of AMP as compared to ACC for attentional bias (group by time interaction p=.073). Changes in craving, liking and saliva were not significantly different between groups (ps=.178-.527). This is the first study to demonstrate that an AMP program can influence eating in obese children. Larger studies are needed to replicate and extend these results

A pilot study evaluating a one-session attention modification training to decrease overeating in obese children.

There are a number of neurocognitive and behavioral mechanisms that contribute to overeating and obesity, including an attentional bias to food cues. Attention modification programs, which implicitly train attention away from specific cues, have been used in anxiety and substance abuse, and could logically be applied to food cues. The purpose of this study was to evaluate the initial efficacy of a single session attention modification training for food cues (AMP) on overeating in overweight and obese children. Twenty-four obese children who eat in the absence of hunger participated in two visits and were assigned to an attention modification program (AMP) or attentional control program (ACC). The AMP program trained attention away 100% of the time from food words to neutral words. The ACC program trained attention 50% of the time to neutral and 50% of the time to food. Outcome measures included the eating in the absence of hunger free access session, and measures of craving, liking and salivation. Results revealed significant treatment effects for EAH percent and EAH kcal (group by time interactions p&lt;.05). Children in the ACC condition showed a significant increase over time in the number of calories consumed in the free access session (within group t=3.09, p=.009) as well as the percent of daily caloric needs consumed in free access (within group t=3.37, p=.006), whereas children in the AMP group demonstrated slight decreases in these variables (within group t=-0.75 and -0.63, respectively). There was a trend suggesting a beneficial effect of AMP as compared to ACC for attentional bias (group by time interaction p=.073). Changes in craving, liking and saliva were not significantly different between groups (ps=.178-.527). This is the first study to demonstrate that an AMP program can influence eating in obese children. Larger studies are needed to replicate and extend these results

Mammalian SWI/SNF complexes promote MyoD-mediated muscle differentiation

Mammalian SWI/SNF complexes are ATP-dependent chromatin remodeling enzymes that have been implicated in the regulation of gene expression, cell-cycle control and oncogenesis. MyoD is a muscle-specific regulator able to induce myogenesis in numerous cell types. To ascertain the requirement for chromatin remodeling enzymes in cellular differentiation processes, we examined MyoD-mediated induction of muscle differentiation in fibroblasts expressing dominant-negative versions of the human brahma-related gene-1 (BRG1) or human brahma (BRM), the ATPase subunits of two distinct SWI/SNF enzymes. We find that induction of the myogenic phenotype is completely abrogated in the presence of the mutant enzymes. We further demonstrate that failure to induce muscle-specific gene expression correlates with inhibition of chromatin remodeling in the promoter region of an endogenous muscle-specific gene. Our results demonstrate that SWI/SNF enzymes promote MyoD-mediated muscle differentiation and indicate that these enzymes function by altering chromatin structure in promoter regions of endogenous, differentiation-specific loci