5,961 research outputs found

    Health Efforts of the War on Poverty

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    Elimination of the light shift in rubidium gas cell frequency standards using pulsed optical pumping

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    Changes in the intensity of the light source in an optically pumped, rubidium, gas cell frequency standard can produce corresponding frequency shifts, with possible adverse effects on the long-term frequency stability. A pulsed optical pumping apparatus was constructed with the intent of investigating the frequency stability in the absence of light shifts. Contrary to original expectations, a small residual frequency shift due to changes in light intensity was experimentally observed. Evidence is given which indicates that this is not a true light-shift effect. Preliminary measurements of the frequency stability of this apparatus, with this small residual pseudo light shift present, are presented. It is shown that this pseudo light shift can be eliminated by using a more homogeneous C-field. This is consistent with the idea that the pseudo light shift is due to inhomogeneity in the physics package (position-shift effect)

    A Mid-Infrared Galaxy Atlas (MIGA)

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    A mid-infrared atlas of part of the Galactic plane (75āˆ˜<l<148āˆ˜,b=Ā±6āˆ˜75^\circ < l < 148^\circ, b = \pm6^\circ) has been constructed using HIRES processed infrared data to provide a mid-infrared data set for the Canadian Galactic Plane Survey (CGPS). The addition of this data set to the CGPS will enable the study of the emission from the smallest components of interstellar dust at an angular resolution comparable to that of the radio, millimetre, and far-infrared data in the CGPS. The Mid-Infrared Galaxy Atlas (MIGA) is a mid-infrared (12 Ī¼\mum and 25 Ī¼\mum) counterpart to the far-infrared IRAS Galaxy Atlas (IGA), and consists of resolution enhanced (āˆ¼0.5ā€²\sim 0.5' resolution) HIRES images along with ancillary maps. This paper describes the processing and characteristics of the atlas, the cross-beam simulation technique used to obtain high-resolution ratio maps, and future plans to extend both the IGA and MIGA.Comment: 38 pages (including 15 tables), 13 figures (8 dithered GIF and 5 EPS). Submitted to Astrophysical Journal Supplement Series. A preprint with higher resolution figures is available at http://www.cita.utoronto.ca/~kerton/publications.htm

    In vitro determination of hemoglobin A1c for diabetes diagnosis and management: technology update

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    It is fascinating to consider the analytical improvements that have occurred since glycated hemoglobin was first used in routine clinical laboratories for diabetes monitoring around 1977; at that time methods displayed poor precision, there were no calibrators or material with assayed values for quality control purposes. This review outlines the major improvements in hemoglobin A1c (HbA1c) measurement that have occurred since its introduction, and reflects on the increased importance of this hemoglobin fraction in the monitoring of glycemic control. The use of HbA1c as a diagnostic tool is discussed in addition to its use in monitoring the patient with diabetes; the biochemistry of HbA1c formation is described, and how these changes to the hemoglobin molecule have been used to develop methods to measure this fraction. Standardization of HbA1c is described in detail; the development of the IFCC Reference Measurement Procedure for HbA1c has enabled global standardization to be achieved which has allowed global targets to be set for glycemic control and diagnosis. The importance of factors that may interfere in the measurement of HbA1c are highlighted

    Space augmentation of military high-level waste disposal

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    Space disposal of selected components of military high-level waste (HLW) is considered. This disposal option offers the promise of eliminating the long-lived radionuclides in military HLW from the earth. A space mission which meets the dual requirements of long-term orbital stability and a maximum of one space shuttle launch per week over a period of 20-40 years, is a heliocentric orbit about halfway between the orbits of earth and Venus. Space disposal of high-level radioactive waste is characterized by long-term predictability and short-term uncertainties which must be reduced to acceptably low levels. For example, failure of either the Orbit Transfer Vehicle after leaving low earth orbit, or the storable propellant stage failure at perihelion would leave the nuclear waste package in an unplanned and potentially unstable orbit. Since potential earth reencounter and subsequent burn-up in the earth's atmosphere is unacceptable, a deep space rendezvous, docking, and retrieval capability must be developed

    Towards self-protecting ubiquitous systems : monitoring trust-based interactions

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    The requirement for spontaneous interaction in ubiquitous computing creates security issues over and above those present in other areas of computing, deeming traditional approaches ineffective. As a result, to support secure collaborations entities must implement self-protective measures. Trust management is a solution well suited to this task as reasoning about future interactions is based on the outcome of past ones. This requires monitoring of interactions as they take place. Such monitoring also allows us to take corrective action when interactions are proceeding unsatisfactorily. In this vein, we first present a trust-based model of interaction based on event structures. We then describe our ongoing work in the development of a monitor architecture which enables self-protective actions to be carried out at critical points during principal interaction. Finally, we discuss some potential directions for future work

    Analysis of air quality management with emphasis on transportation sources

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    The current environment and practices of air quality management were examined for three regions: Denver, Phoenix, and the South Coast Air Basin of California. These regions were chosen because the majority of their air pollution emissions are related to mobile sources. The impact of auto exhaust on the air quality management process is characterized and assessed. An examination of the uncertainties in air pollutant measurements, emission inventories, meteorological parameters, atmospheric chemistry, and air quality simulation models is performed. The implications of these uncertainties to current air quality management practices is discussed. A set of corrective actions are recommended to reduce these uncertainties

    Experimental Generation and Observation of Intrinsic Localized Spin Wave Modes in an Antiferromagnet

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    By driving with a microwave pulse the lowest frequency antiferromagnetic resonance of the quasi 1-D biaxial antiferromagnet (C_2 H_5 NH_3)_2 CuCl_4 into an unstable region intrinsic localized spin waves have been generated and detected in the spin wave gap. These findings are consistent with the prediction that nonlinearity plus lattice discreteness can lead to localized excitations with dimensions comparable to the lattice constant.Comment: 10 pages, 4 figures, accepted for publication in Physical Review Letter

    Bauhinia Rhapsody : the literary journal of Lingnan University 2018-2019

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    Editor\u27s Note The Lingnan Literary Journal itself, the book you have now in your hands, is a work of Lingnan University students. That which we write and leave behind is how we communicate with the future, and it is in this way that the students of Lingnan, here during the 2018-2019 academic year, will continue to have impact long after they have left the campus here in Tuen Mun, nestled against the foothills of Hong Kongā€™s mountains. The work you see here is that of my own students, from either of my two classes, Arts, Creative Writing & Journalism, taught in the Fall and Spring of my time here, and Journalism Principles & Social Media, taught only in the Spring. Save for Mary Garcia who designed the covers, the editorial team came from my Fall class. There is also the writing and visual efforts of students I have never met in person, but which spoke to all of us. Others I met along the way at numerous events on campus, engaging them in conversation and asking them to submit their work. The team also recruited, through passive means like posters, and through setting up tables on campus. Still other constributions came from Professor Inghamā€™s class, gifting us with interesting intertextual work based on songs and poems, a favorite method of his for inspiring his studentsā€™ creativity. Mikeā€™s deep desire to engage with his students, in and out of the classroom, was also something that inspired me to always try to give more and reach out to students across the spectrum at Lingnan. I believe through my efforts and the efforts of so many others, the journal as you see it now represents a broad range of Lingnanā€™s diverse student body, locals and exchange students alike.https://commons.ln.edu.hk/eng_studentjournal/1003/thumbnail.jp

    Factors Influencing Consumer Likelihood of Purchasing a Flexible-Fuel or Hybrid Automobile

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    Developing fuels and vehicles that reduce our reliance on fossil fuels has become a priority due to the threat of global climate change and desire for reduced dependence on oil imports. Flexible-fuel vehicles that can run on ethanol/gasoline blends of up to 85% ethanol and hybrid electric vehicles present two such opportunities. While production of both flexible-fuel and hybrid vehicles is increasing, there is still a great deal of uncertainty about how consumers will respond to these products. To address this uncertainty, data was collected through an online survey of automobile owners that asked respondents how likely they were to choose either a flexible-fuel or hybrid vehicle as their next vehicle. A bivariate probit model was used to jointly analyze responses to these two questions. The results show that, while there was some overlap in the factors correlated with perceived likelihood of choosing one of these two types of automobiles, there were also clear differences. These results should benefit policymakers, marketers and academics seeking a better understanding of the respective markets for these vehicles.flexible-fuel vehicles, ethanol, E85, hybrid electric vehicles, Demand and Price Analysis, Environmental Economics and Policy, Resource /Energy Economics and Policy,
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