3,232 research outputs found

    Finding the Center of Mass of a Soft Spring

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    This article shows how to use calculus to find the center of mass position of a soft cylindrical helical spring that is suspended vertically. The spring is non-uniformly stretched by the action of gravity. A general expression for the vertical position of the center of mass is obtained.Comment: LaTeX, 7 pages, 2 figures. Minor changes to agree with published versio

    Enhancing Student Learning in the Online Instructional Environment Through the Use of Universal Design for Learning

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    As college faculty who prepare future teachers, we strive to teach our students through instruction and modeling best practices in teaching. We constantly evaluate our teaching and make adjustments to include updated knowledge about effective instruction. The evaluation and adjustments made to our courses lend themselves to action research. We take what we learn from our research and make appropriate changes to better meet the diverse needs of students. This article provides an overview of a final project that used Universal Design for Learning (UDL) for assessing student knowledge. This research focused on the principle of Multiple Means of Action and Expression and the impact the UDL final project had on student learning as well as overall perceptions of the project. Results indicate that participants enjoyed the final project and that it impacted their learning. Students reported enjoying having choice in how they demonstrated their understanding of the content

    Betty Jean Oaks Talking About Farm Life in Primera, Cameron County, Texas During 1920s and 1930s

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    An interview with Betty Jean (Hamilton) Oaks, an RGV community member, explores her experience in the border region. Conducted by Ruby Aguilar, a local school teacher participating in the Porciones to Colonias project. Betty Jean was born in 1925 in Primera, TX. Mrs. Oaks provides an overview of her genealogy and describes farm life in the Valley, providing details about crops and harvests, transportation, local businesses, and more. Betty J. Oaks was interviewed by Ruby A. Aguilar. Mayra Zepeda (videographer)https://scholarworks.utrgv.edu/chapsoralhistories/1109/thumbnail.jp

    A report on the nonlinear squeezed states and their non-classical properties of a generalized isotonic oscillator

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    We construct nonlinear squeezed states of a generalized isotonic oscillator potential. We demonstrate the non-existence of dual counterpart of nonlinear squeezed states in this system. We investigate statistical properties exhibited by the squeezed states, in particular Mandel's parameter, second-order correlation function, photon number distributions and parameter A3A_3 in detail. We also examine the quadrature and amplitude-squared squeezing effects. Finally, we derive expression for the ss-parameterized quasi-probability distribution function of these states. All these information about the system are new to the literature.Comment: Accepted for publication in J. Phys. A: Math. Theo

    A baseline assessment of migratory and resident bird use of a prairie restoration site in eastern Washington

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    Prairies, and other types of grassland ecosystems, have suffered some of the most profound losses worldwide, due to anthropogenic factors such as fossil fuel extraction, agriculture, and climate change. Likewise, organisms inhabiting grassland ecosystems have become extirpated across much of their historical range, not the least of which has been a 50% decline in grassland birds since the 1960s. In response to losses of intact prairie in eastern Washington, a 120-ac site has been established on the EWU campus to regenerate native prairie and monitor changes in the ecosystem as native plants recolonize and replace non-natives. Because birds are an important indicator species of ecosystem health, the goal of our research was to estimate baseline abundance and diversity of birds at the prairie restoration site before restoration takes place. We also assessed bird abundance and diversity at a small, intact prairie remnant 20 mi north of the EWU campus to compare current bird use of the restoration site with that of an intact prairie system. We assessed bird abundance and bird diversity using the line-transect method. We established one transect at each site, and counted all birds seen or heard within 50 meters of the transects. Our findings will provide a baseline of knowledge about how and when birds will begin to reinhabit the EWU restoration site and inform future restoration efforts on the benefits and outcomes of restoring native grasslands locally, and worldwide


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    Mathematical programming-based systems analysis is used to examine the consequences of alternative operation configuration for the agricultural operations within the Texas Department of Criminal Justice. Continuation versus elimination of the total operation as well as individual operating departments are considered. Methodology includes a firm systems operation model combined with capital budgeting and an integer programming based investment model. Results indicate the resources realize a positive return as a whole, but some enterprises are not using resources profitably. The integer investment model is found to be superior for investigating whether to continue multiple interrelated enterprises.agribusiness, enterprise selection, mathematical programming, optimal enterprise organization, Agribusiness,

    Methylomic markers of persistent childhood asthma: a longitudinal study of asthma-discordant monozygotic twins.

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    This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.Asthma is the most common chronic inflammatory disorder in children. The aetiology of asthma pathology is complex and highly heterogeneous, involving the interplay between genetic and environmental risk factors that is hypothesized to involve epigenetic processes. Our aim was to explore whether methylomic variation in early childhood is associated with discordance for asthma symptoms within monozygotic (MZ) twin pairs recruited from the Environmental Risk (E-Risk) longitudinal twin study. We also aimed to identify differences in DNA methylation that are associated with asthma that develops in childhood and persists into early adulthood as these may represent useful prognostic biomarkers. RESULTS: We examined genome-wide patterns of DNA methylation in buccal cell samples collected from 37 MZ twin pairs discordant for asthma at age 10. DNA methylation at individual CpG sites demonstrated significant variability within discordant MZ twin pairs with the top-ranked nominally significant differentially methylated position (DMP) located in the HGSNAT gene. We stratified our analysis by assessing DNA methylation differences in a sub-group of MZ twin pairs who remained persistently discordant for asthma at age 18. The top-ranked nominally significant DMP associated with persisting asthma is located in the vicinity of the HLX gene, which has been previously implicated in childhood asthma. CONCLUSIONS: We identified DNA methylation differences associated with childhood asthma in peripheral DNA samples from discordant MZ twin pairs. Our data suggest that differences in DNA methylation associated with childhood asthma which persists into early adulthood are distinct from those associated with asthma which remits.Medical Research Council (MRC)National Institute of Child Health and Development (NICHD)American Asthma FoundationMRC Centenary Awar
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