11 research outputs found
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Bridging the digital divide for hard-to-reach groups
Boeltzig and Pilling identified specific groups of people who typically are not connected to the Internet and examined the circumstances of each - rural, poor, disabled, seniors, and ethnic minorities. They focused on how these groups of people, such as homebound individuals, could benefit most from using online government services. They also identified technical as well as social barriers that limit access. Their recommendations are aimed at both increasing access for these targeted groups and increasing use by individuals in the targeted groups. They also provide valuable recommendations aimed at service or application providers who have a major role in increasing both access and accessibility.
The case studies resulted in insights and lessons that are broadly applicable. Based on the case studies, the authors offer recommendations that are practical and serve as useful guides to practitioners and policy makers at all levels of government
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US and UK Routes to Employment: Strategies to Improve Integrated Service Delivery to People with Disabilities
In this report, the authors examine the experience of the United States and United Kingdom in developing effective strategies for providing integrated service delivery. The report examines what works and what doesn't work, and provides a roadmap to improving services for individuals with disabilities. While more research is needed, the report identifies 12 strategies to strengthen integrated service delivery systems, and to assist individuals with disabilities in gaining and maintaining productive employment. Implementing these strategies can benefit clients, who have the opportunity to realize their potential more fully; the taxpayer, who is paying less for disability assistance; and society at large, which gains the productive skill of talented individuals
Improved S factor of the 12C(p,γ)13N reaction at E=320–620 keV and the 422 keV resonance
The 12C(p,γ)13N reaction is the onset process of both the CNO and hot CNO cycles that drive massive star, red and asymptotic giant branch star, and novae nucleosynthesis. The 12C(p,γ)13N rate affects the final abundances of the stable 12,13C nuclides with ramifications for meteoritic carbon isotopic abundances and the s-process neutron source strength. Here, an underground measurement of the 12C(p,γ)13N cross section is reported. The present data, obtained at the Felsenkeller shallow-underground laboratory in Dresden (Germany), encompass the 320–620 keV center of mass energy range to include the wide and poorly constrained E=422 keV resonance that dominates the rate at high temperatures. This work's S-factor results, lower than literature by 25%, are included in a comprehensive R-matrix fit, and the energy of the 12+ first excited state of 13N is found to be 2369.6(4) keV with a radiative and proton width of 0.49(3) eV and 34.9(2) keV, respectively. A reaction rate, based on the present R-matrix fit and extrapolation, is suggested
Effect of beam energy straggling on resonant yield in thin gas targets: The cases 22Ne(p, \u3b3)23Na and 14N(p, \u3b3)15O
When deriving resonance strengths using the thick-target yield approximation, for very narrow resonances it may be necessary to take beam energy straggling into account. This applies to gas targets of a few keV width, especially if there is some additional structure in target stoichiometry or detection efficiency. The correction for this effect is shown and tested on recent studies of narrow resonances in the 22Ne(p, \u3b3)23Na and 14N(p, \u3b3)15O reactions
Big Bang 6 Li nucleosynthesis studied deep underground (LUNA collaboration)
The correct prediction of the abundances of the light nuclides produced during the epoch of Big Bang Nucleosynthesis (BBN) is one of the main topics of modern cosmology. For many of the nuclear re- actions that are relevant for this epoch, direct experimental cross section data are available, ushering the so-called \u201cage of precision\u201d. The present work addresses an exception to this current status: the 2 H( \u3b1, \u3b3) 6 Li reaction that controls 6 Li production in the Big Bang. Recent controversial observations of 6 Li in metal-poor stars have heightened the interest in understanding primordial 6 Li production. If confirmed, these observations would lead to a second cosmological lithium problem, in addition to the well-known 7 Li problem. In the present work, the direct experimental cross section data on 2 H( \u3b1, \u3b3) 6 Li in the BBN energy range are reported. The measurement has been performed deep underground at the LUNA (Lab- oratory for Underground Nuclear Astrophysics) 400 kV accelerator in the Laboratori Nazionali del Gran Sasso, Italy. The cross section has been directly measured at the energies of interest for Big Bang Nucle- osynthesis for the first time, at E cm = 80, 93, 120, and 133 keV. Based on the new data, the 2 H( \u3b1, \u3b3) 6 Li thermonuclear reaction rate has been derived. Our rate is even lower than previously reported, thus in- creasing the discrepancy between predicted Big Bang 6 Li abundance and the amount of primordial 6 Li inferred from observations
Big Bang 6Li nucleosynthesis studied deep underground (LUNA collaboration)
The correct prediction of the abundances of the light nuclides produced during the epoch of Big Bang Nucleosynthesis (BBN) is one of the main topics of modern cosmology. For many of the nuclear reactions that are relevant for this epoch, direct experimental cross section data are available, ushering the so-called “age of precision”. The present work addresses an exception to this current status: the 2H(α,γ)6Li reaction that controls 6Li production in the Big Bang. Recent controversial observations of 6Li in metal-poor stars have heightened the interest in understanding primordial 6Li production. If confirmed, these observations would lead to a second cosmological lithium problem, in addition to the well-known 7Li problem. In the present work, the direct experimental cross section data on 2H(α,γ)6Li in the BBN energy range are reported. The measurement has been performed deep underground at the LUNA (Laboratory for Underground Nuclear Astrophysics) 400 kV accelerator in the Laboratori Nazionali del Gran Sasso, Italy. The cross section has been directly measured at the energies of interest for Big Bang Nucleosynthesis for the first time, at Ecm=80, 93, 120, and 133 keV. Based on the new data, the 2H(α,γ)6Li thermonuclear reaction rate has been derived. Our rate is even lower than previously reported, thus increasing the discrepancy between predicted Big Bang 6Li abundance and the amount of primordial 6Li inferred from observations