4,061 research outputs found

    Study of low frequency hydromagnetic waves using ATS-1 data

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    Low frequency oscillations of the magnetic field at ATS-1 were analyzed for the 25 month data interval, Dec., 1966 through 1968. Irregular oscillations and those associated with magnetic storms were excluded from the analysis. Of the 222 events identified, 170 were found to be oscillating predominantly transverse to the background magnetic field. The oscillations were observed to occur most frequently in the early afternoon hours. They also seemed to occur more frequently during Dec., Jan., and Feb. than at any other time of the year. During a given event, the frequency was fairly constant. The event duration varied between a minimum of 10 min. and a maximum of 14 hrs and 26 min. During a given event the amplitude varied

    Opportunities for Energy Conservation and Improved Comfort From Wind Washing Retrofits in Two-Story Homes - Part I

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    Wind washing is a general term referring to diminished thermal control caused by air movement over or through a thermal barrier. The primary focus of this paper is towards a specific type of wind washing where wind can push attic air into the floor cavity between first and second stories of the home through ineffective (or missing) air barriers separating attic space from the floor cavity. A second type of wind washing studied in this project involved insulation batts on knee walls where space between the batts and the wall board allowed air movement against the gypsum wall board. During hot weather, the first type of wind washing pushes hot air into the floor cavity (between the first and second stories) thereby heating ceiling, floor, and interior wall surfaces (see Figures 1 and 2). Condensation may occur on cold supply duct surfaces within the floor cavity resulting in ceiling moisture damage. In cold climates, cold air from wind washing can chill surfaces within the interior floor space and result in frozen water pipes. Through the summer of 2009, a field study tested thirty-two two-story homes and found significant wind washing potential in 40% of the homes. Part I of this paper will highlight the evaluation methods used and the extent of wind washing found in this study. Repairs and energy monitoring were completed in six of these homes to evaluate retrofit methods and cost effectiveness of retrofit solutions. These results are discussed in Part II of this paper.Florida Solar Energy Center, University of Central Florid

    Toward a descriptive model of galactic cosmic rays in the heliosphere

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    Researchers review the elements that enter into phenomenological models of the composition, energy spectra, and the spatial and temporal variations of galactic cosmic rays, including the so-called anomalous cosmic ray component. Starting from an existing model, designed to describe the behavior of cosmic rays in the near-Earth environment, researchers suggest possible updates and improvements to this model, and then propose a quantitative approach for extending such a model into other regions of the heliosphere

    Significant initial results from the environmental measurements experiment on ATS-6

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    The Applications Technology Satellite (ATS-6), launched into synchronous orbit on 30 May 1974, carried a set of six particle detectors and a triaxial fluxgate magnetometer. The particle detectors were able to determine the ion and electron distribution functions from 1 to greater than 10 to the 8th power eV. It was found that the magnetic field is weaker and more tilted than predicted by models which neglect internal plasma and that there is a seasonal dependence to the magnitude and tilt. ATS-6 magnetic field measurements showed the effects of field-aligned currents associated with substorms, and large fluxes of field-aligned particles were observed with the particle detectors. Encounters with the plasmasphere revealed the existence of warm plasma with temperatures up to 30 eV. A variety of correlated waves in both the particles and fields were observed: pulsation continuous oscillations, seen predominantly in the plasmasphere bulge; ultralow frequency (ULF) standing waves; ring current proton ULF waves; and low frequency waves that modulate the energetic electrons. In additon, large scale waves on the energetic-ion-trapping boundary were observed, and the intensity of energetic electrons was modulated in association with the passage of sector boundaries of the interplanetary magnetic field

    Opportunities for Energy Conservation and Improved Comfort From Wind Washing Retrofits in Two-Story Homes - Part I

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    Wind washing is a general term referring to diminished thermal control caused by air movement over or through a thermal barrier. The primary focus of this paper is towards a specific type of wind washing where wind can push attic air into the floor cavity between first and second stories of the home through ineffective (or missing) air barriers separating attic space from the floor cavity. A second type of wind washing studied in this project involved insulation batts on knee walls where space between the batts and the wall board allowed air movement against the gypsum wall board. During hot weather, the first type of wind washing pushes hot air into the floor cavity (between the first and second stories) thereby heating ceiling, floor, and interior wall surfaces (see Figures 1 and 2). Condensation may occur on cold supply duct surfaces within the floor cavity resulting in ceiling moisture damage. In cold climates, cold air from wind washing can chill surfaces within the interior floor space and result in frozen water pipes. Through the summer of 2009, a field study tested thirty-two two-story homes and found significant wind washing potential in 40% of the homes. Part I of this paper will highlight the evaluation methods used and the extent of wind washing found in this study. Repairs and energy monitoring were completed in six of these homes to evaluate retrofit methods and cost effectiveness of retrofit solutions. These results are discussed in Part II of this paper.Florida Solar Energy Center, University of Central Florid

    Getting To Excellence: What Every Educator Should Know About Consequences of Beliefs, Attitudes, and Paradigms for the Reconstruction of an Academically Unacceptable Middle School

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    In this chapter a discussion of a salient dimension of the external environment in which today’s educators find themselves practicing – the policy context - is presented. Critical elements of this discussion include a truncated history of the encroachment on local control of the schools and the ensuing standardized-tests-based accountability and standardized testing movement. We also pay some attention to growing efforts to push back against these movements. We conclude this chapter with perspectives of a set of scholarly informants on quality, equity, and adequacy. Our effort in this chapter is to trace the political distance traveled from education defined by the diverse beliefs, values, attitudes and paradigms specific to the New England, Middle, and Southern colonies to the current emphasis on standardized-tests-based accountability, standards, and testing as they impact or fail to impact quality, equity, and adequacy – the context in which the Willie Ray Smith, Sr. Science and Medical Technology Magnet Middle School was previously branded academically unacceptable but now academically acceptable

    Impact of fecal microbiota transplantation on gut bacterial bile acid metabolism in humans

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    Fecal microbiota transplantation (FMT) is a promising therapeutic modality for the treatment and prevention of metabolic disease. We previously conducted a double-blind, randomized, placebo-controlled pilot trial of FMT in obese metabolically healthy patients in which we found that FMT enhanced gut bacterial bile acid metabolism and delayed the development of impaired glucose tolerance relative to the placebo control group. Therefore, we conducted a secondary analysis of fecal samples collected from these patients to assess the potential gut microbial species contributing to the effect of FMT to improve metabolic health and increase gut bacterial bile acid metabolism. Fecal samples collected at baseline and after 4 weeks of FMT or placebo treatment underwent shotgun metagenomic analysis. Ultra-high-performance liquid chromatography-mass spectrometry was used to profile fecal bile acids. FMT-enriched bacteria that have been implicated in gut bile acid metabolism included Desulfovibrio fairfieldensis and Clostridium hylemonae. To identify candidate bacteria involved in gut microbial bile acid metabolism, we assessed correlations between bacterial species abundance and bile acid profile, with a focus on bile acid products of gut bacterial metabolism. Bacteroides ovatus and Phocaeicola dorei were positively correlated with unconjugated bile acids. Bifidobacterium adolescentis, Collinsella aerofaciens, and Faecalibacterium prausnitzii were positively correlated with secondary bile acids. Together, these data identify several candidate bacteria that may contribute to the metabolic benefits of FMT and gut bacterial bile acid metabolism that requires further functional validation

    Biomass and nutrient dynamics associated with slash fires in neotropical dry forests

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    Unprecedented rates of deforestation and biomass burning in tropical dry forests are dramatically influencing biogeochemical cycles, resulting in resource depletion, declines in biodiversity, and atmospheric pollution. We quantified the effects of defores- tation and varying levels of slash-fire severity on nutrient losses and redistribution in a second-growth tropical dry forest ("Caatinga") near Serra Talhada, Pernambuco, Brazil. Total aboveground biomass prior to burning was 74 Mg/ha. Nitrogen and phosphorus concentrations were highest in litter, leaves attached to slash, and fine wood debris (<0.64 cm diameter). While these components comprised only 30% of the prefire aboveground biomass, they accounted for -60% of the aboveground pools of N and P. Three experi- mental fires were conducted during the 1989 burning season. In these treatments con- sumption was 78, 88, and 95% of the total aboveground biomass. As much as 96% of the prefire aboveground N and C pools and 56% of the prefire aboveground P pool was lost during combustion processes. Nitrogen losses exceeded 500 kg/ha and P losses exceeded 20 kg/ha in the fires of the greatest severity. With increasing fire severity, the concentrations of N and P in ash decreased while the concentration of Ca increased. This indicates greater amounts of these nutrients were volatilized (i.e., greater ecosystem losses occurred) with increasing fire severity. Following fire, up to 47% of the residual aboveground N and 84% of the residual aboveground P were in the form of ash, which was quickly lost from the site via wind erosion. Fires appeared to have a minor immediate effect on total N, C, or P in the soils. However, soils in forests with no history of cultivation had significantly higher concentrations of C and P than second-growth forests. Based upon the measured losses of nutrients from these single slash-burning events, it would likely require a century or more of fallow for reaccumulation to occur. However, current fallow periods in this region are 15 yr or less

    High-Sensitivity Serum Calcitonin Assays Applied to Screening for Thyroid C-Cell Disease in Multiple Endocrine Neoplasia Type 2A

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    Two serum calcitonin assays with sensitivities ≤ 10 pg/mL were compared to our standard radioimmunoassay (sensitivity 100 pg/mL) in multiple endocrine neoplasia type 2A (MEN 2A) screening. Values from the Nichols displacement radioimmunoassay averaged 38% higher than values from the CIS immunoradiometric assay; values from both were highly correlated, r = 0.845. In three individuals, both of the newer assays revealed abnormalities in pentagastrin tests three to four years before abnormalities were detected by the standard assay. Pentagastrin tests after total thyroidectomy were assayed by the newer methods in patients with medullary thyroid carcinoma (MTC) diagnosed at initial testing (group I); in patients with early MTC diagnosed by prospective screening (group ll); and in patients with pure C-cell hyperplasia detected by prospective screening (group III). At least 64% of group I, at least 25% of group II, but none of group III had detectable postoperative C-cell function. Conclusions: 1) The previous estimate of 12 years as median age of onset of C-cell disease in MEN 2A is probably three to four years too old. 2) Patients diagnosed with early MTC by screening had not necessarily skipped a preneoplastic phase of C-cell hyperplasia. At least some early disease was not detected by the standard assay. Higher sensitivity assays should improve screening for C-cell disease by earlier disease detection. 3) Biochemical cure by thyroidectomy after the development of MTC is not as frequent as previously thought, but the apparent cure rate of pure C-cell hyperplasia remains 100%

    MANAGING COMMON NIGHTHAWKS AT MCCONNELL AIR FORCE BASE, KANSAS, TO REDUCE AIRCRAFT STRIKES

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    McConnell Air Force Base (AFB) experiences a unique bird/aircraft hazard problem with migrating common nighthawks from August to October. Nighthawks are the most commonly struck species at McConnell AFB, representing about 38% of reported bird/aircraft strikes. During August and September, nighthawks represented 82% of the bird strikes found on the airfield. Approaches for managing nighthawks on and around airfields are limited because of the night environment, logistics and an incomplete understanding of nighthawk behavior. We determined the number of nighthawks using McConnell AFB and associated foraging, loafing and roosting areas, analyzed their food habits, and developed a translocation management strategy to reduce hazards to aircraft. During 1998, 1999 and 2000, we observed 600, 540 and 920 nighthawks, respectively, on the airfield. The greatest activity on the airfield occurred from September 27-30 in 1998, September 9- 14 in 1999, and September 6-8 in 2000. The peak number of nighthawks observed using the airfield during these periods was 142, 90 and 118, respectively. Nighthawks foraged around the airfield mainly between 1800 and 2200 and usually roosted on the airfield about 1800 with a peak between 2200 and 0200. During one 2-hour survey period in 1999 and 2000, 37 and 59 nighthawks, respectively, were flushed from the airfield. Thirty-seven nighthawks collected during the study consumed mostly corn earworm moths (Noctuidae) and beetles (Scarabaeidae). Management of nighthawks on McConnell AFB has been difficult because commonly used hazing techniques seem to be ineffective; these birds usually return to the same roosting location after being flushed, which can present an even greater risk to aircraft. We developed and evaluated a unique technique for capturing and translocating nighthawks from the airfield. Only 1 of 214 nighthawks translocated 88 km from McConnell AFB returned. Nighthawk/aircraft strikes at McConnell AFB declined from 9 in 1998, when no translocation was conducted, to 0 in 1999 and 3 in 2000
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