70 research outputs found

    Testing predictions used to build an agrivoltaics installation on a small-scale educational model

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    Models are valuable tools for explaining and testing systems. Small-scale models can be especially useful for educational purposes. For models to be useful, they have to accurately depict the larger system that they are describing. A novel man-made system, known as an agrivoltaic structure, is being constructed at Biosphere 2 near Oracle, Arizona. The word agrivoltaic is a combination of agriculture and photovoltaics, or solar farming. My research involved creating a small-scale version of this system for educational purposes. The model of this system tested two predictions: that plants will grow better in the shade of a panel and that the plants will cool the solar panel through transpiration. These two predictions were tested using low-tech solutions that are affordable for classroom teachers. Predictions were tested using water and scales to measure soil moisture; infrared guns to measure plant and panel temperature; and HOBO air temperature sensors. There was little quantitative data to support the claim that plants grew better in shade than sun; however, the model system is young and may need time to grow. While some observational evidence supported the second prediction, the data was not significant. Both sets of data appeared to be highly dependent on environmental factors, such as sun position. Even without upholding the predictions, this model worked well as an educational tool, allowing students to better understand the value of research and the benefits and limitations of models

    Cornwall Avenue revitalization: south anchor site

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    This project proposes a revitalization of the downtown area of Bellingham, WA, in an attempt to reestablish the city center\u27s primacy as a commercial center. This EIA focuses on the southern section of the entire proposal. New development proposed for this project includes a four-story mixed use department store on the corner of Chestnut Street and Cornwall Avenue as well as a 260-space, four-story, above-ground parking structure on the corner of Cornwall Avenue and East Maple Street Mixed-use infill is also proposed for existing structures on Cornwall Avenue Addressing transportation issues, the project proposes that certain one-way streets be converted to two-way streets in the downtown area, a bike-share program be implemented, the trail system be further interconnected, and a trolleybus incorporated into the mass transit system

    Predictors for Using a HIV Self-Test Among Migrant and Seasonal Farmworkers in North Carolina

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    Background: Approximately, two million migrant and seasonal farmworkers (MSF) work in the United States annually. Several factors, such as lack of access to healthcare services and health behaviors, contribute to risk of HIV transmission. Relatively few studies have explored MSF knowledge of HIV transmission and testing options. Methods: A 12-question, self-administered survey of farmworkers (n = 178) from 19 migrant camps was conducted. The survey assessed knowledge of factors related to HIV transmission, testing, and intention to use a HIV home-test kit. Results: Participants with knowledge of treatment for HIV (p = 0.03) and that condom use protects against HIV (p = 0.04) were more willing to express intent to use a home test kit than those with less knowledge. Concern among farmworkers that HIV was a very or somewhat serious problem in their community was associated with expressing intent to use a home test kit (OR = 2.3, 95% CI = 0.92–5.5). Respondents with less knowledge were less likely to use a home test kit. Conclusions: MSF were concerned about HIV in their community and would be willing to use to a home test kit. This pilot study provides a basis for additional research related to HIV testing within the MSF community.ECU Open Access Publishing Support Fun

    Faint High Latitude Carbon Stars Discovered by the Sloan Digital Sky Survey: Methods and Initial Results

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    We report the discovery of 39 Faint High Latitude Carbon Stars (FHLCs) from Sloan Digital Sky Survey commissioning data. The objects, each selected photometrically and verified spectroscopically, range over 16.6 < r* < 20.0, and show a diversity of temperatures as judged by both colors and NaD line strengths. At the completion of the Sloan Survey, there will be many hundred homogeneously selected and observed FHLCs in this sample. We present proper motion measures for each object, indicating that the sample is a mixture of extremely distant (>100 kpc) halo giant stars, useful for constraining halo dynamics, plus members of the recently-recognized exotic class of very nearby dwarf carbon (dC) stars. Motions, and thus dC classification, are inferred for 40-50 percent of the sample, depending on the level of statistical significance invoked. The new list of dC stars presented here, although selected from only a small fraction of the final SDSS, doubles the number of such objects found by all previous methods. (Abstract abridged).Comment: Accepted for publication in The Astronomical Journal, Vol. 124, Sep. 2002, 40 pages, 7 figures, AASTeX v5.

    Animal Welfare in Conservation Breeding: Applications and Challenges

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    Animal welfare and conservation breeding have overlapping and compatible goals that are occasionally divergent. Efforts to improve enclosures, provide enriching experiences, and address behavioral and physical needs further the causes of animal welfare in all zoo settings. However, by mitigating stress, increasing behavioral competence, and enhancing reproduction, health, and survival, conservation breeding programs must also focus on preparing animals for release into the wild. Therefore, conservation breeding facilities must strike a balance of promoting high welfare, while minimizing the effects of captivity to increase population sustainability. As part of the Hawaii Endangered Bird Conservation Program, San Diego Zoo Global operates two captive breeding facilities that house a number of endangered Hawaiian bird species. At our facilities we aim to increase captive animal welfare through husbandry, nutrition, behavior-based enrichment, and integrated veterinary practices. These efforts help foster a captive environment that promotes the development of species-typical behaviors. By using the “Opportunities to Thrive” guiding principles, we outline an outcome-based welfare strategy, and detail some of the related management inputs, such as transitioning to parental rearing, and conducting veterinary exams remotely. Throughout we highlight our evidence-based approach for evaluating our practices, by monitoring welfare and the effectiveness of our inputs. Additionally we focus on some of the unique challenges associated with improving welfare in conservation breeding facilitates and outline concrete future steps for improving and evaluating welfare outcomes that also meet conservation goals

    Association of PHACTR1 with Coronary Artery Calcium Differs by Sex and Cigarette Smoking.

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    Background: Coronary artery calcium (CAC) is a marker of subclinical atherosclerosis and is a complex heritable trait with both genetic and environmental risk factors, including sex and smoking. Methods: We performed genome-wide association (GWA) analyses for CAC among all participants and stratified by sex in the COPDGene study (n = 6144 participants of European ancestry and n = 2589 participants of African ancestry) with replication in the Diabetes Heart Study (DHS). We adjusted for age, sex, current smoking status, BMI, diabetes, self-reported high blood pressure, self-reported high cholesterol, and genetic ancestry (as summarized by principal components computed within each racial group). For the significant signals from the GWA analyses, we examined the single nucleotide polymorphism (SNP) by sex interactions, stratified by smoking status (current vs. former), and tested for a SNP by smoking status interaction on CAC. Results: We identified genome-wide significant associations for CAC in the chromosome 9p21 region [CDKN2B-AS1] among all COPDGene participants (p = 7.1 Ă— 10-14) and among males (p = 1.0 Ă— 10-9), but the signal was not genome-wide significant among females (p = 6.4 Ă— 10-6). For the sex stratified GWA analyses among females, the chromosome 6p24 region [PHACTR1] had a genome-wide significant association (p = 4.4 Ă— 10-8) with CAC, but this signal was not genome-wide significant among all COPDGene participants (p = 1.7 Ă— 10-7) or males (p = 0.03). There was a significant interaction for the SNP rs9349379 in PHACTR1 with sex (p = 0.02), but the interaction was not significant for the SNP rs10757272 in CDKN2B-AS1 with sex (p = 0.21). In addition, PHACTR1 had a stronger association with CAC among current smokers (p = 6.2 Ă— 10-7) than former smokers (p = 7.5 Ă— 10-3) and the SNP by smoking status interaction was marginally significant (p = 0.03). CDKN2B-AS1 had a strong association with CAC among both former (p = 7.7 Ă— 10-8) and current smokers (p = 1.7 Ă— 10-7) and the SNP by smoking status interaction was not significant (p = 0.40). Conclusions: Among current and former smokers of European ancestry in the COPDGene study, we identified a genome-wide significant association in the chromosome 6p24 region [PHACTR1] with CAC among females, but not among males. This region had a significant SNP by sex and SNP by smoking interaction on CAC

    Extensive soot compaction by cloud processing from laboratory and field observations

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    Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models

    Extensive Soot Compaction by Cloud Processing from Laboratory and Field Observations

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    Soot particles form during combustion of carbonaceous materials and impact climate and air quality. When freshly emitted, they are typically fractal-like aggregates. After atmospheric aging, they can act as cloud condensation nuclei, and water condensation or evaporation restructure them to more compact aggregates, affecting their optical, aerodynamic, and surface properties. Here we survey the morphology of ambient soot particles from various locations and different environmental and aging conditions. We used electron microscopy and show extensive soot compaction after cloud processing. We further performed laboratory experiments to simulate atmospheric cloud processing under controlled conditions. We find that soot particles sampled after evaporating the cloud droplets, are significantly more compact than freshly emitted and interstitial soot, confirming that cloud processing, not just exposure to high humidity, compacts soot. Our findings have implications for how the radiative, surface, and aerodynamic properties, and the fate of soot particles are represented in numerical models.Peer reviewe

    New insights on the Draco dwarf spheroidal galaxy from SDSS: a larger radius and no tidal tails

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    We have investigated the spatial extent and structure of the Draco dwarf spheroidal galaxy using deep wide-field multicolor CCD photometry from the Sloan Digital Sky Survey (SDSS). Our study covers an area of 27 square degrees around the center of the Draco dwarf. We show that the spatial distribution of Draco's red giants, red horizontal branch stars and subgiants down to i=21.7 mag does not provide evidence for the existence of tidally induced tails or a halo of unbound stars. The radial profile can be fit by King models as well as by a generalized exponential. The core radius and the limiting (or tidal) radius along the major axis are 7.7' and 40.1', respectively, making Draco 40% larger than previously measured. Down to our magnitude limit tidal effects can only exist at a level of 10^-3 of the central surface density of Draco or below. The regular structure of Draco found from the new data argues against it being a portion of an unbound tidal stream and lends support to the assumption of dynamical equilibrium. We estimate Draco's total mass to be 2.2 - 3.5 times 10^7 solar masses. We obtain an overall mass-to-light ratio of 146+-42 or 92+-28 solar masses depending on the details of the mass and luminosity estimates. In summary, our results strengthen the case for a strongly dark matter dominated, bound stellar system. (Abstract strongly abridged).Comment: 30 pages, 11 figures (in part with degraded resolution). Accepted for publication in the Astronomical Journa

    Whole-Genome Sequencing Uncovers Two Loci for Coronary Artery Calcification and Identifies Arse as a Regulator of Vascular Calcification

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    Coronary artery calcification (CAC) is a measure of atherosclerosis and a well-established predictor of coronary artery disease (CAD) events. Here we describe a genome-wide association study (GWAS) of CAC in 22,400 participants from multiple ancestral groups. We confirmed associations with four known loci and identified two additional loci associated with CAC (ARSE and MMP16), with evidence of significant associations in replication analyses for both novel loci. Functional assays of ARSE and MMP16 in human vascular smooth muscle cells (VSMCs) demonstrate that ARSE is a promoter of VSMC calcification and VSMC phenotype switching from a contractile to a calcifying or osteogenic phenotype. Furthermore, we show that the association of variants near ARSE with reduced CAC is likely explained by reduced ARSE expression with the G allele of enhancer variant rs5982944. Our study highlights ARSE as an important contributor to atherosclerotic vascular calcification, and a potential drug target for vascular calcific disease
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