403 research outputs found

    Teachers\u27 Experiences with Interactions in Online Classes: A Case Study

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    The purpose of this qualitative case study is to describe the experiences of teachers interacting with students in an online learning environment at Township School District. The theory guiding this study is Moore’s transactional distance theory as it examines how meaningful interactions can minimize the transactional distance in distance learning or remote learning environments. Data from teacher interviews, focus groups, and teacher generated writing samples were used to provide an understanding of how teachers support and promote interactions in online learning environments. Participants were teachers with at least one-year experience teaching remotely or online. All participants were from the same medium sized school district in central Illinois, with a student population of nearly 8,000. This study adds to the literature by sharing high school teachers’ perspectives and experiences of creating and supporting interactions in an online learning environment. The central research question asked, “What are the experiences of high school teachers creating and fostering meaningful interactions in online learning environments?” NVivo coding was utilized to identify codes generated directly from participant responses. The results of the study indicated that teachers created and supported a variety of meaningful interactions. Teachers experienced challenges, adopted new teaching strategies, embraced interactive digital content, and gained a new perspective on students’ home life

    Mechanically fastened joints in woven fabric composites

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    Strength analysis for composite bolted joints involves the mating of a stress analysis with an appropriate mode specific failure criterion for each of the primary failure modes. The stress analysis and failure criteria are independent of each other and can be manipulated separately in order to optimize the strength analysis package formed by their coupling. Material properties tests were conducted on rubber toughened graphite-epoxy material to measure the basic strength and stiffness in the warp and fill directions and in shear. Test matrices are summarized for investigations of laminate configuration, stacking sequence, fastener diameter, edge distance, fastener half spacing, laminate thickness, and fastener torque. A three dimensional finite element analysis computer program was written and failure criteria for net tension, shearout, and bearing were determined

    Use of Capsaicin for Desensitization of the Cough Reflex

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    Somatotyping of Division I Athletes

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    Somatotyping has previously examined athletes\u27 genetic morphology. Categorization of somatotyping can be utilized in athletes for specialized, adaptive sports performance. PURPOSE: The purpose of this study was to report somatotyping differences (ectomorph, mesomorph, and endomorph) in selected Division I athletes. METHOD: 39 male football athletes and seven female softball Division I athletes were recruited for this investigation. Height (m), weight (kg), waist-to-hip ratio (cm), and a 4-site skinfold measurement was collected. Skinfold locations were recorded from the triceps (mm), subscapular (mm), supraspinal (mm), and the medial calf (mm). Biepicondylar breadth measures of the humerus (cm), and the femur (cm) were recorded at a respective 90°. Additionally, the girth of the subject’s dominant upper arm (cm) and dominant calf (cm) were recorded. All measurement locations were taken from the Heath-Carter Anthropometric protocol, respectfully. The Heath Carter Somatotype Worksheet consists of a rating scale that is based on a 3-component categorization. All measures are considered when calculating a participant\u27s score. Scores between .5 and 2.5 are low, 3 to 5 are moderate, 5.5 to 7 are high and anything over a 7.5 is considered very high. The first component calculated scores of endomorphy, the second calculated mesomorphy scores, and the last component calculated ectomorph scores. Using these measurements, equations are used to determine a participant’s score to a specific somatotype. The athletes\u27 numbers were then processed and plotted on a 2-D graph plotting the somatotype (X= ectomorph-endomorph, Y=2 x mesomorphy- (endomorphy+ectomorph)). RESULTS: There was a clear indication that somatotyping had variety based on sports and position specialization in football athletes. Football athletes consisted of 6 endomorphs, 30 mesomorphs, and 3 ectomorphs, while softball athletes consisted of 7 meso-endomorphs. CONCLUSION: Due to the anthropometric position differences in male football athletes there was a considerable amount of variety and lack of specificity, while the female softball athletes consisted of a lesser variety in anthropometric measures

    Spatial divergence in the proportions of genes encoding toxic peptide synthesis among populations of the cyanobacterium Planktothrix in European lakes

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    It has been frequently reported that seasonal changes in toxin production by cyanobacteria are due to changes in the proportion of toxic/nontoxic genotypes in parallel to increases or decreases in population density during the seasonal cycle of bloom formation. In order to find out whether there is a relationship between the proportion of genes encoding toxic peptide synthesis and population density of Planktothrix spp. we compared the proportion of three gene regions that are indicative of the synthesis of the toxic heptapeptide microcystin (mcyB), and the bioactive peptides aeruginoside (aerB) and anabaenopeptin (apnC) in samples from 23 lakes of five European countries (n=153). The mcyB, aerB, and apnC genes occurred in 99%, 99%, and 97% of the samples, respectively, and on average comprised 60 ± 3%, 22 ± 2%, and 54 ± 4% of the total population, respectively. Although the populations differed widely in abundance (10−3–103 mm3 L−1) no dependence of the proportion of the mcyB, aerB, and apnC genes on the density of the total population was found. In contrast populations differed significantly in their average mcyB, aerB, and apnC gene proportions, with no change between prebloom and bloom conditions. These results emphasize stable population-specific differences in mcyB, aerB, and apnC proportions that are independent from seasonal influences

    Regional and scale-specific effects of land use on amphibian diversity [poster]

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    Background/Question/Methods Habitat loss and degradation influence amphibian distributions and are important drivers of population declines. Our previous research demonstrated that road disturbance, development and wetland area consistently influence amphibian richness across regions of the U.S. Here, we examined the relative importance of these factors in different regions and at multiple spatial scales. Understanding the scales at which habitat disturbance may be affecting amphibian distributions is important for conservation planning. Specifically, we asked: 1) Over what spatial scales do distinct landscape features affect amphibian richness? and 2) Do road types (non-rural and rural) have similar effects on amphibian richness? This is the second year of a collaborative, nationwide project involving 11 U.S. colleges integrated within undergraduate biology curricula. We summarized North American Amphibian Monitoring Program data in 13 Eastern and Central U.S states and used geographic information systems to extract landscape data for 471 survey locations. We developed models to quantify the influence of landscape variables on amphibian species richness and site occupancy across five concentric buffers ranging from 300m to 10,000m. Results/Conclusions Across spatial scales, development, road density and agriculture were the best predictors of amphibian richness and site occupancy by individual species. Across regions, we found that scale did not exert a large influence on how landscape features influenced amphibian richness as effects were largely comparable across buffers. However, development and percent impervious surface had stronger influence on richness at smaller spatial scales. Richness was lower at survey locations with higher densities of non-rural and rural roads, and non-rural road density had a larger negative effect at smaller scales. Within regions, landscape features driving patterns of species richness varied. The scales at which these factors were associated with richness were highly variable within regions, suggesting the scale effects may be region specific. Our project demonstrates that networks of undergraduate students can collaborate to compile and analyze large ecological data sets, while engaging students in authentic and inquiry-based learning in landscape-scale ecology

    Complex chloroplast RNA metabolism: just debugging the genetic programme?

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    <p>Abstract</p> <p>Background</p> <p>The gene expression system of chloroplasts is far more complex than that of their cyanobacterial progenitor. This gain in complexity affects in particular RNA metabolism, specifically the transcription and maturation of RNA. Mature chloroplast RNA is generated by a plethora of nuclear-encoded proteins acquired or recruited during plant evolution, comprising additional RNA polymerases and sigma factors, and sequence-specific RNA maturation factors promoting RNA splicing, editing, end formation and translatability. Despite years of intensive research, we still lack a comprehensive explanation for this complexity.</p> <p>Results</p> <p>We inspected the available literature and genome databases for information on components of RNA metabolism in land plant chloroplasts. In particular, new inventions of chloroplast-specific mechanisms and the expansion of some gene/protein families detected in land plants lead us to suggest that the primary function of the additional nuclear-encoded components found in chloroplasts is the transgenomic suppression of point mutations, fixation of which occurred due to an enhanced genetic drift exhibited by chloroplast genomes. We further speculate that a fast evolution of transgenomic suppressors occurred after the water-to-land transition of plants.</p> <p>Conclusion</p> <p>Our inspections indicate that several chloroplast-specific mechanisms evolved in land plants to remedy point mutations that occurred after the water-to-land transition. Thus, the complexity of chloroplast gene expression evolved to guarantee the functionality of chloroplast genetic information and may not, with some exceptions, be involved in regulatory functions.</p
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