194 research outputs found

    Influence of Warping on Stress for Restrained Concrete Slabs: For Application to CRCP

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    Continuously-reinforced concrete pavement (CRCP) is widely used in transportation system because of its low maintenance requirement. However, the need for large volumes of steel creates a high cost for new construction. The Illinois Tollway is preparing to substantially renovate highways in and around Chicago and this work seeks to understand how concretes of varying mixture designs can be made thinner by reducing the amount of built-in stress. The experiment examines warping in beams subjected to various degrees of restraint, in an effort to assess effectiveness at reducing warping in continuously reinforced concrete pavements. Value added methodologies such as internal curing with fine lightweight aggregate and topically-applied shrinkage-reducing admixture (SRA) were applied to a controlled concrete mixture design. The experimental program examines the warping of a composite concrete-steel beam with differing degrees of restraint, accomplished through using a 1/4 and ½” steel plate with a 2.5 concrete section . Each beam undergoes seven days of uni-axial warping, subjected to a controlled temperature and humidity environment (23+/-2C and 50 +/- 2 % RH), with a linear variable differential transformer to monitor endpoint deflection. Results indicate that as degree of restraint increases, the associated, or built-in , stress increases too; however, the deflection decreases by as much as a factor of two between unrestrained and 1/2 restraint. These findings potentially serve as a solution for effectively reducing the amount of concrete necessary for sustained loading associated with CRCP while mitigating warping and stresses associated

    Changes in the relationship between self-reference and emotional valence as a function of dysphoria

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    The self-positivity bias is found to be an aspect of normal cognitive function. Changes in this bias are usually associated with changes in emotional states, such as dysphoria or depression. The aim of the present study was to clarify the role of emotional valence within self-referential processing. By asking non-dysphoric and dysphoric individuals to rate separately the emotional and self-referential content of a set of 240 words, it was possible to identify the differences in the relationship between self-reference and emotional valence, which are associated with dysphoria. The results support the existence of the self-positivity bias in non-dysphoric individuals. More interestingly, dysphoric individuals were able to accurately identify the emotional content of the word stimuli. They failed, however, to associate this emotional valence with self-reference. These findings are discussed in terms of attributional self-biases and their consequences for cognition

    Atomic diffraction from nanostructured optical potentials

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    We develop a versatile theoretical approach to the study of cold-atom diffractive scattering from light-field gratings by combining calculations of the optical near-field, generated by evanescent waves close to the surface of periodic nanostructured arrays, together with advanced atom wavepacket propagation on this optical potential.Comment: 8 figures, 10 pages, submitted to Phys. Rev.

    Applications of Laboratory Technology in the Evaluation of the Risk of Rabies Transmissions by Biting Dogs and Cats

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    While rabies is not a common disease in domestic animal species of the United States, potential exposures to rabies in the form of bites are very common and increasing. A nationwide study conducted among general hospitals shows that 1 percent of emergency room visits are for animal bites, of which 80-90 percent are inflicted by the dog (Callaham 1980). This figure is conservative, as the study did not include pediatric hospitals, the bite of victims that progress only to a physician\u27s office, or those that receive no medical care at all. In Missouri alone, this study would infer about 1500 dog bites per year reaching only the general hospital. The number of dog and other animal bites across the country is unknown but may safely be assumed to be staggering in magnitude

    Rivastigmine: an open-label, observational study of safety and effectiveness in treating patients with Alzheimer's disease for up to 5 years

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    BACKGROUND: Rivastigmine, a butyl- and acetylcholinesterase inhibitor, is approved for symptomatic treatment of Alzheimer's disease (AD). Data supporting the safety and efficacy of second-generation cholinesterase inhibitors, such as rivastigmine, are available for treatment up to 1 year, with limited data up to 2 1/2 years. The purpose of this report is to present safety and effectiveness data for rivastigmine therapy in patients with mild to moderately severe AD receiving treatment for up to 5 years. METHODS: An observational approach was used to study 37 patients with originally mild to moderate AD receiving rivastigmine as a therapy for AD in an open-label extension (ENA713, B352 Study Group, 1998). RESULTS: The initial trial demonstrated rivastigmine was well-tolerated and effective in terms of cognition, global functioning and activities of daily living. In this open label extension, high-dose rivastigmine therapy was safe and well tolerated over a 5-year period. Two thirds of the participants still enrolled at week 234 were in the original high-dose rivastigmine group during the double-blind phase, suggesting that early therapy may confer some benefit in delaying long-term progression of symptoms. CONCLUSIONS: Long-term cholinesterase inhibition therapy with rivastigmine was well tolerated, with no dropouts due to adverse effects past the initial titration period. Early initiation of treatment, with titration to high-dose therapy, may have an advantage in delaying progression of the illness

    A Global Upper Atmosphere Observatory Using of Lidar on the International Space Station

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    A concept for hosting a lidar facility for the upper atmosphere on the International Space Station (ISS) is presented and discussed. The concept is based on utilizing an existing Large Space Optics mirror having a 2.37-m aperture as the primary mirror in its receiver. This large aperture provides for hosting several transmitter systems to retrieve density, temperature, and wind measurements for several upper atmospheric species. Thus the concept provides for measurements over a wide altitude range (80-600 km), at various time and spatial resolutions, and hosting on the ISS provides nearly global coverage. The baseline concept includes transmitters and receivers for atomic oxygen (80-500 km), metastable helium (400-600 km), and sodium (80-110 km). The facility is conceived as being flexible such that other transmitter/receiver systems could be added to allow the possibility of other species to be studied, such as iron. The presentation discusses the transformative science that would be gained by such an observatory by combining the nearly global coverage afforded by the ISS orbit with the extension of powerful lidar techniques to high altitudes. The challenges in realizing such an observatory are discussed, as are current plans and partnerships to meet those challenges. The presentation also reports on the development status of several components, primarily various independent transmitter/receiver systems, that are under consideration for the baseline observatory. Several institutions are performing these developments

    Differential Requirement for Utrophin in the Induced Pluripotent Stem Cell Correction of Muscle versus Fat in Muscular Dystrophy Mice

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    Duchenne muscular dystrophy (DMD) is an incurable degenerative muscle disorder. We injected WT mouse induced pluripotent stem cells (iPSCs) into mdx and mdx∶utrophin mutant blastocysts, which are predisposed to develop DMD with an increasing degree of severity (mdx <<< mdx∶utrophin). In mdx chimeras, iPSC-dystrophin was supplied to the muscle sarcolemma to effect corrections at morphological and functional levels. Dystrobrevin was observed in dystrophin-positive and, at a lesser extent, utrophin-positive areas. In the mdx∶utrophin mutant chimeras, although iPSC-dystrophin was also supplied to the muscle sarcolemma, mice still displayed poor skeletal muscle histopathology, and negligible levels of dystrobrevin in dystrophin- and utrophin-negative areas. Not only dystrophin-expressing tissues are affected by iPSCs. Mdx and mdx∶utrophin mice have reduced fat/body weight ratio, but iPSC injection normalized this parameter in both mdx and mdx∶utrophin chimeras, despite the fact that utrophin was compromised in the mdx∶utrophin chimeric fat. The results suggest that the presence of utrophin is required for the iPSC-corrections in skeletal muscle. Furthermore, the results highlight a potential (utrophin-independent) non-cell autonomous role for iPSC-dystrophin in the corrections of non-muscle tissue like fat, which is intimately related to the muscle

    The 2010 Interim Report of the Long-Baseline Neutrino Experiment Collaboration Physics Working Groups

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    Corresponding author R.J.Wilson ([email protected]); 113 pages, 90 figuresCorresponding author R.J.Wilson ([email protected]); 113 pages, 90 figuresIn early 2010, the Long-Baseline Neutrino Experiment (LBNE) science collaboration initiated a study to investigate the physics potential of the experiment with a broad set of different beam, near- and far-detector configurations. Nine initial topics were identified as scientific areas that motivate construction of a long-baseline neutrino experiment with a very large far detector. We summarize the scientific justification for each topic and the estimated performance for a set of far detector reference configurations. We report also on a study of optimized beam parameters and the physics capability of proposed Near Detector configurations. This document was presented to the collaboration in fall 2010 and updated with minor modifications in early 2011

    The 2010 Interim Report of the Long-Baseline Neutrino Experiment Collaboration Physics Working Groups

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    In early 2010, the Long-Baseline Neutrino Experiment (LBNE) science collaboration initiated a study to investigate the physics potential of the experiment with a broad set of different beam, near- and far-detector configurations. Nine initial topics were identified as scientific areas that motivate construction of a long-baseline neutrino experiment with a very large far detector. We summarize the scientific justification for each topic and the estimated performance for a set of far detector reference configurations. We report also on a study of optimized beam parameters and the physics capability of proposed Near Detector configurations. This document was presented to the collaboration in fall 2010 and updated with minor modifications in early 2011.Comment: Corresponding author R.J.Wilson ([email protected]); 113 pages, 90 figure
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