686 research outputs found
Vibration characteristics of ring-stiffened orthotropic shells of revolution
Computer program solves vibration modes and frequencies of thin shells of revolution having general meridional curvature and orthotropic elastic properties in order to evaluate the dynamic behavior of structures with thin shelled components
Towards a publicly available, map-based regional software tool to estimate unregulated daily streamflow at ungauged rivers
Streamflow information is critical for addressing any number of hydrologic problems. Often, streamflow information is needed at locations that are ungauged and, therefore, have no observations on which to base water management decisions. Furthermore, there has been increasing need for daily streamflow time series to manage rivers for both human and ecological functions. To facilitate negotiation between human and ecological demands for water, this paper presents the first publicly available, map-based, regional software tool to estimate historical, unregulated, daily streamflow time series (streamflow not affected by human alteration such as dams or water withdrawals) at any user-selected ungauged river location. The map interface allows users to locate and click on a river location, which then links to a spreadsheet-based program that computes estimates of daily streamflow for the river location selected. For a demonstration region in the northeast United States, daily streamflow was, in general, shown to be reliably estimated by the software tool. Estimating the highest and lowest streamflows that occurred in the demonstration region over the period from 1960 through 2004 also was accomplished but with more difficulty and limitations. The software tool provides a general framework that can be applied to other regions for which daily streamflow estimates are needed
Third Report on Chicken Genes and Chromosomes 2015
Following on from the First Report on Chicken Genes and Chromosomes [Schmid et al., 2000] and the Second Report in 2005 [Schmid et al., 2005], we are pleased to publish this long-awaited Third Report on the latest developments in chicken genomics. The First Report highlighted the availability of genetic and physical maps, while the Second Report was published as the chicken genome sequence was released. This report comes at a time of huge technological advances (particularly in sequencing methodologies) which have allowed us to examine the chicken genome in detail not possible until now. This has also heralded an explosion in avian genomics, with the current availability of more than 48 bird genomes [Zhang G et al., 2014b; Eöry et al., 2015], with many more planned
The Origins Space Telescope: mission concept overview
The Origins Space Telescope (OST) will trace the history of our origins from the time dust and heavy elements permanently altered the cosmic landscape to present-day life. How did the universe evolve in response to its changing ingredients? How common are life-bearing planets? To accomplish its scientific objectives, OST will operate at mid- and far-infrared wavelengths and offer superlative sensitivity and new spectroscopic capabilities. The OST study team will present a scientifically compelling, executable mission concept to the 2020 Decadal Survey in Astrophysics. To understand the concept solution space, our team studied two alternative mission concepts. We report on the study approach and describe both of these concepts, give the rationale for major design decisions, and briefly describe the mission-enabling technology
More than Fast Food: Development of a Story Map to Compare Adolescent Perceptions and Observations of Their Food Environments and Related Food Behaviors
The purpose of this convergent, multiphase, mixed methods study was to better understand the perceptions of adolescents’ food environments and related food behaviors using grounded visualization and story mapping. Adolescents from one high school (13–16 years) in the southeastern United States were evaluated via data from health behavior surveys (n = 75), school environment maps, focus groups (n = 5 groups), and Photovoice (n = 6) from October 2016 to April 2017. Data from each phase were integrated using grounded visualization and new themes were identified (n = 7). A story map using ArcGIS Online was developed from data integration, depicting the newly identified themes. Participants failed to meet national recommendations for fruit and vegetable intake (2.71 cups). Focus group and Photovoice findings indicated the need for convenience food items in all environments. The story map is an online, interactive dissemination of information, with five maps, embedded quotes from focus groups, narrative passages with data interpretation, pictures to highlight themes, and a comparison of the participants’ food environments. Story mapping and qualitative geographic information systems (GIS) approaches may be useful when depicting adolescent food environments and related food behaviors. Further research is needed when evaluating story maps and how individuals can be trained to create their own maps
More than Fast Food: Development of a Story Map to Compare Adolescent Perceptions and Observations of Their Food Environments and Related Food Behaviors
The purpose of this convergent, multiphase, mixed methods study was to better understand the perceptions of adolescents’ food environments and related food behaviors using grounded visualization and story mapping. Adolescents from one high school (13–16 years) in the southeastern United States were evaluated via data from health behavior surveys (n = 75), school environment maps, focus groups (n = 5 groups), and Photovoice (n = 6) from October 2016 to April 2017. Data from each phase were integrated using grounded visualization and new themes were identified (n = 7). A story map using ArcGIS Online was developed from data integration, depicting the newly identified themes. Participants failed to meet national recommendations for fruit and vegetable intake (2.71 cups). Focus group and Photovoice findings indicated the need for convenience food items in all environments. The story map is an online, interactive dissemination of information, with five maps, embedded quotes from focus groups, narrative passages with data interpretation, pictures to highlight themes, and a comparison of the participants’ food environments. Story mapping and qualitative geographic information systems (GIS) approaches may be useful when depicting adolescent food environments and related food behaviors. Further research is needed when evaluating story maps and how individuals can be trained to create their own maps
End-to-end numerical modeling of the Roman Space Telescope coronagraph
The Roman Space Telescope will have the first advanced coronagraph in space,
with deformable mirrors for wavefront control, low-order wavefront sensing and
maintenance, and a photon-counting detector. It is expected to be able to
detect and characterize mature, giant exoplanets in reflected visible light.
Over the past decade the performance of the coronagraph in its flight
environment has been simulated with increasingly detailed diffraction and
structural/thermal finite element modeling. With the instrument now being
integrated in preparation for launch within the next few years, the present
state of the end-to-end modeling is described, including the measured flight
components such as deformable mirrors. The coronagraphic modes are thoroughly
described, including characteristics most readily derived from modeling. The
methods for diffraction propagation, wavefront control, and structural and
thermal finite-element modeling are detailed. The techniques and procedures
developed for the instrument will serve as a foundation for future
coronagraphic missions such as the Habitable Worlds Observatory.Comment: 113 pages, 85 figures, to be published in SPIE Journal of
Astronomical Telescopes, Instruments, and System
Expenditure, Coping, and Academic Behaviors Among Food-Insecure College Students at 10 Higher Education Institutes in the Appalachian and Southeastern Regions
Background
A number of studies have measured college student food insecurity prevalence higher than the national average; however, no multicampus regional study among students at 4-y institutions has been undertaken in the Appalachian and Southeast regions of the United States. Objectives
The aims of this study were to determine the prevalence of food insecurity among college students in the Appalachian and Southeastern regions of the United States, and to determine the association between food-insecurity status and money expenditures, coping strategies, and academic performance among a regional sample of college students. Methods
This regional, cross-sectional, online survey study included 13,642 college students at 10 public universities. Food-insecurity status was measured through the use of the USDA Adult Food Security Survey. The outcomes were associations between food insecurity and behaviors determined with the use of the money expenditure scale (MES), the coping strategy scale (CSS), and the academic progress scale (APS). A forward-selection logistic regression model was used with all variables significant from individual Pearson chi-square and Wilcoxon analyses. The significance criterion α for all tests was 0.05. Results
The prevalence of food insecurity at the universities ranged from 22.4% to 51.8% with an average prevalence of 30.5% for the full sample. From the forward-selection logistic regression model, MES (OR: 1.47; 95% CI: 1.40, 1.55), CSS (OR: 1.19; 95% CI: 1.18, 1.21), and APS (OR: 0.95; 95% CI: 0.91, 0.99) scores remained significant predictors of food insecurity. Grade point average, academic year, health, race/ethnicity, financial aid, cooking frequency, and health insurance also remained significant predictors of food security status. Conclusions
Food insecurity prevalence was higher than the national average. Food-insecure college students were more likely to display high money expenditures and exhibit coping behaviors, and to have poor academic performance
Expenditure, Coping, and Academic Behaviors Among Food-Insecure College Students at 10 Higher Education Institutes in the Appalachian and Southeastern Regions
Background
A number of studies have measured college student food insecurity prevalence higher than the national average; however, no multicampus regional study among students at 4-y institutions has been undertaken in the Appalachian and Southeast regions of the United States. Objectives
The aims of this study were to determine the prevalence of food insecurity among college students in the Appalachian and Southeastern regions of the United States, and to determine the association between food-insecurity status and money expenditures, coping strategies, and academic performance among a regional sample of college students. Methods
This regional, cross-sectional, online survey study included 13,642 college students at 10 public universities. Food-insecurity status was measured through the use of the USDA Adult Food Security Survey. The outcomes were associations between food insecurity and behaviors determined with the use of the money expenditure scale (MES), the coping strategy scale (CSS), and the academic progress scale (APS). A forward-selection logistic regression model was used with all variables significant from individual Pearson chi-square and Wilcoxon analyses. The significance criterion α for all tests was 0.05. Results
The prevalence of food insecurity at the universities ranged from 22.4% to 51.8% with an average prevalence of 30.5% for the full sample. From the forward-selection logistic regression model, MES (OR: 1.47; 95% CI: 1.40, 1.55), CSS (OR: 1.19; 95% CI: 1.18, 1.21), and APS (OR: 0.95; 95% CI: 0.91, 0.99) scores remained significant predictors of food insecurity. Grade point average, academic year, health, race/ethnicity, financial aid, cooking frequency, and health insurance also remained significant predictors of food security status. Conclusions
Food insecurity prevalence was higher than the national average. Food-insecure college students were more likely to display high money expenditures and exhibit coping behaviors, and to have poor academic performance
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