146,858 research outputs found
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E-government: A comparison of strategies in local authorities in the UK and Norway
In Europe almost all countries have implemented some form of e-government, not to mention the UK and Norway which are now both well into their sixth year of e-government implementation. These six years have seen various strategic plans formulated, implemented and also intermittently postponed in the two countries. Although time may result in the amplification of e-government experience for Norway and the UK, the postponement of implementation deadlines indicates that not only political and social issues, but also strategic and organisational issues need to be addressed when formulating plans for deploying e-government. Using empirical research this paper examines the strategies adopted by the UK and Norway in the context of aligning central and local government plans for implementing e-government services. While technical, political and social issues are considered as key areas to be addressed in any e-government exploitation plan; this paper examines how different perspectives on e-government definition, strategy, awareness and related organisational change influence implementation. The need to align central and local e-government plans, guidelines for local level implementation, user centred solutions, strong leadership and a common understanding of the definition of e-government are highlighted in the paper as some of the key components of good e-government implementation practice
On the Power-Law Tail in the Mass Function of Protostellar Condensations and Stars
We explore the idea that the power-law tail in the mass function of
protostellar condensations and stars arises from the accretion of ambient cloud
material on to a condensation, coupled with a nonuniform (exponential)
distribution of accretion lifetimes. This model allows for the generation of
power-law distributions in all star-forming regions, even if condensations
start with a lognormal mass distribution, as may be expected from the central
limit theorem, and supported by some recent numerical simulations of turbulent
molecular clouds. For a condensation mass with growth rate , an analytic three-parameter probability density function is derived; it
resembles a lognormal at low mass and has a pure power-law high-mass tail. An
approximate power-law tail is also expected for other growth laws, and we
calculate the distribution for the plausible case .
Furthermore, any single time snapshot of the masses of condensations that are
still accreting (and are of varying ages) also yields a distribution with a
power-law tail similar to that of the IMF.Comment: 5 pages, 4 figures, to appear in MNRAS (Letters section
Opportunistic infection as a cause of transient viremia in chronically infected HIV patients under treatment with HAART
When highly active antiretroviral therapy is administered for long periods of
time to HIV-1 infected patients, most patients achieve viral loads that are
``undetectable'' by standard assay (i.e., HIV-1 RNA copies/ml). Yet
despite exhibiting sustained viral loads below the level of detection, a number
of these patients experience unexplained episodes of transient viremia or viral
"blips". We propose here that transient activation of the immune system by
opportunistic infection may explain these episodes of viremia. Indeed, immune
activation by opportunistic infection may spur HIV replication, replenish viral
reservoirs and contribute to accelerated disease progression. In order to
investigate the effects of concurrent infection on chronically infected HIV
patients under treatment with highly active antiretroviral therapy (HAART), we
extend a simple dynamic model of the effects of vaccination on HIV infection
[Jones and Perelson, JAIDS 31:369-377, 2002] to include growing pathogens. We
then propose a more realistic model for immune cell expansion in the presence
of pathogen, and include this in a set of competing models that allow low
baseline viral loads in the presence of drug treatment. Programmed expansion of
immune cells upon exposure to antigen is a feature not previously included in
HIV models, and one that is especially important to consider when simulating an
immune response to opportunistic infection. Using these models we show that
viral blips with realistic duration and amplitude can be generated by
concurrent infections in HAART treated patients.Comment: 30 pages, 9 figures, 1 table. Submitted to Bulletin of Mathematical
Biolog
Coal-rock interface detector
A coal-rock interface detector is presented which employs a radioactive source and radiation sensor. The source and sensor are separately and independently suspended and positioned against a mine surface of hydraulic pistons, which are biased from an air cushioned source of pressurized hydraulic fluid
The identification and production of varieties that increase the value of oats as a profitable component of organic production
Two experiments, one comprising husked, and the other naked, oats were established at Wakelyns Agroforestry, Suffolk in October 2004 to determine traits and varieties of oats suited to organic systems, and whether growing variety mixtures conferred any advantage. Unselected F2 breeding lines were also included for selection. Husked varieties had relatively higher yields; this may have been partly the result of poor establishment in the naked varieties. Variety height was found to be an important characteristic; tall oat varieties out-yielded the dwarfs. Two of the three variety mixtures containing the naked oat variety Expression yielded 8 and 9 % higher than the average of the component varieties. The data will be verified in the second year of replicated trials (2005/06), which will include the best performing husked and naked varieties, and a mixture of superior IGER-bred F2 breeding lines
The use of ERTS/LANDSAT imagery in relation to airborne remote sensing for terrain analysis in Western Queensland, Australia
The author has identified the following significant results. LANDSAT 1 and 2 imagery contrast the geology of the Cloncurry-Dobbyn and the Gregory River-Mt. Isa areas very clearly. Known major structural features and lithological units are clearly displayed while, hitherto unknown lineaments were revealed. Throughout this area, similar rock types produce similar spectral signatures, e.g. quartzites produce light signatures, iron rich rocks produce dark signatures. More geological data are discernible at the 1:50,000 scale than on the 1:250,000 scale. Ore horizons may be identified at the 1:50,000 scale, particularly where they are associated with iron rich rocks. On the level plains north of Cloncurry, distinctive spectral signatures produced by the combined reflectances of plant cover, soils, and geology, distinguish different types of superficial deposits. Existing and former channels of the Cloncurry and Williams Rivers are distinguished at the 1:50,000 scale on both the LANDSAT 1 and 2 imagery. On the Cloncurry Plains, fence lines are discernible on the 1:50,000 LANDSAT 2 imagery
Production of Millisecond Dips in Sco X-1 Count Rates by Dead Time Effects
Chang et al. (2006) reported millisecond duration dips in the X-ray intensity
of Sco X-1 and attributed them to occultations of the source by small
trans-Neptunian objects (TNOs). We have found multiple lines of evidence that
these dips are not astronomical in origin, but rather the result of high-energy
charged particle events in the RXTE PCA detectors. Our analysis of the RXTE
data indicates that at most 10% of the observed dips in Sco X-1 could be due to
occultations by TNOs, and, furthermore, we find no positive or supporting
evidence for any of them being due to TNOs. We therefore believe that it is a
mistake to conclude that any TNOs have been detected via occultation of Sco
X-1.Comment: Submitted to ApJ; uses emulateapj.cls, 8 pages with 8 figure
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Reduction of internal noise in auditory perceptual learning
This paper examines what mechanisms underlie auditory perceptual learning. Fifteen normal hearing adults performed two-alternative, forced choice, pure tone frequency discrimination for four sessions. External variability was introduced by adding a zero-mean Gaussian random variable to the frequency of each tone. Measures of internal noise, encoding efficiency, bias, and inattentiveness were derived using four methods (model fit, classification boundary, psychometric function, and double-pass consistency). The four methods gave convergent estimates of internal noise, which was found to decrease from 4.52 to 2.93âHz with practice. No group-mean changes in encoding efficiency, bias, or inattentiveness were observed. It is concluded that learned improvements in frequency discrimination primarily reflect a reduction in internal noise. Data from highly experienced listeners and neural networks performing the same task are also reported. These results also indicated that auditory learning represents internal noise reduction, potentially through the re-weighting of frequency-specific channels
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