17,473 research outputs found
A comparison of efficient approximations for a weighted sum of chi-squared random variables
Quarkonium production via recombination
The contrast between model predictions for the transverse momentum spectra of
J/Psi observed in Au-Au collisions at RHIC is extended to include effects of
nuclear absorption. We find that the difference between initial production and
recombination is enhanced in the most central collisions. Models utilizing a
combination of these sources may eventually be able to place constraints on
their relative magnitudes.Comment: Based on invited plenary talk at the 2nd International Conference on
Hard and Electromagnetic Probes of High-Energy Nuclear Collisions, Asilomar,
CA, June 9-16, 2006, to be published in Nucl. Phys.
Preliminary Results for LP VPE X-Ray Detectors
Thick epitaxial layers have been grown using Low Pressure Vapour Phase
Epitaxy techniques with low free carrier concentrations . This type of material
is attractive as a medium for X-ray detection, because of its high conversion
efficiency for X-rays in the medically interesting energy range.Comment: 4 pages. PS file only - original in WORD. Also available at
http://ppewww.ph.gla.ac.uk/preprints/97/07
Nutrient characterisation of river inflow into the estuaries of the Gouritz Water Management Area, South Africa
This study provides an overview of the nutrient status of river inflow into the estuaries within the Gouritz Water Management Area (WMA) of South Africa. Riverine inputs are a major source of macronutrients to estuaries and the adjacent coastal environments. Long-term water quality monitoring data (dissolved inorganic nitrogen, i.e. DIN; and dissolved inorganic phosphorus, i.e. DIP), collected by the Department of Water Affairs (DWA), were used to assess historical trends of river nutrient inflow within the Gouritz WMA. The results indicate that DIP concentrations exceeded the eutrophic limits for aquatic ecosystems (DWA) in 50% of the catchments assessed. Anthropogenic activities such as agriculture, wastewater discharge, urbanisation, and afforestation were significant factors influencing nutrient levels within these rivers. For the majority of the river systems (approx. 80%) there was no significant correlation (P > 0.05) between inorganic nutrient levels and freshwater inflow from the catchments. Wastewater treatment plant (WWTP) data (DWA) were assessed to explore the reasons for this ‘disconnect’ between freshwater inflow and inorganic nutrient levels. Results indicate that the Gwaing (267.73 kg·d-1 DIN; 77.46 kg·d-1 DIP), Goukou (49.71 kg·d-1 DIN; 17.38 kg·d-1 DIP), Knysna (41.77 kg·d-1 DIN; 13.92 kg·d-1 DIP) and Hartenbos (37.73 kg·d-1 DIN; 21.39 kg·d-1 DIP) systems received the highest daily loads from WWTPs. The Gwaing and Hartenbos estuaries would be most vulnerable to increased nutrient loading because of their small size and prolonged periods of mouth closure. The study highlights the importance of water quality monitoring of river inflows into coastal ecosystems, as it is needed to assess pollution trends and identify management priorities.Keywords: Water quality, eutrophication, inorganic nutrients, wastewater discharge
TERCEIRIZAÇÃO NA EDUCAÇÃO: PERSPECTIVAS SOBRE O PROJETO DE REGULAMENTAÇÃO DOS SERVIÇOS TERCEIRIZADOS
A partir da aprovação do projeto de lei 4330/04 na câmara dos deputados, o qual propõe a regulamentação dos serviços terceirizados no Brasil, desenvolve-se a discussão acerca dos possíveis impactos deste projeto às relações trabalhistas contemporâneas. A partir dos fundamentos da valorização da força de trabalho no regime capitalista, investiga-se e analisa-se os principais argumentos de alguns estudiosos sobre esta temática, frente à terceirização, confrontando-os com o posicionamento dos gestores educacionais entrevistados. Nota-se, no decorrer do estudo, que a posição dos gestores, em geral, é fundada em uma lógica mercadológica, sendo que sua visão se norteia pelos interesses da organização, o que conflita com a avaliação dos especialistas da área trabalhistas e de estudos sociais, analisados, os quais, sobretudo, tem sua posição consolidada pelos impactos que a proposta de terceirização acarretaria nos trabalhadores, submetendo-os à precariedade, informalidade e baixa remuneração de suas funções, e no serviço/produto entregue aos consumidores
Recent results on GaAs detectors - 137
The present understanding of the charge collection in GaAs detectors with
respect to the materials used and its processing are discussed. The radiation
induced degradation of the charge collection efficiency and the leakage current
of the detectors are summarised. The status of strip and pixel detectors for
the ATLAS experiment are reported along with the latest results from GaAs X-ray
detectors for non-high energy physics applications.Comment: 7 pages. 4 postscript figures + 1 postscript preprint logo + 1 LaTeX
file + 1 style file. Also available at
http://ppewww.ph.gla.ac.uk/preprints/97/05
\epsilon-regularity for systems involving non-local, antisymmetric operators
We prove an epsilon-regularity theorem for critical and super-critical
systems with a non-local antisymmetric operator on the right-hand side.
These systems contain as special cases, Euler-Lagrange equations of
conformally invariant variational functionals as Rivi\`ere treated them, and
also Euler-Lagrange equations of fractional harmonic maps introduced by Da
Lio-Rivi\`ere.
In particular, the arguments presented here give new and uniform proofs of
the regularity results by Rivi\`ere, Rivi\`ere-Struwe, Da-Lio-Rivi\`ere, and
also the integrability results by Sharp-Topping and Sharp, not discriminating
between the classical local, and the non-local situations
Safety and efficacy of oral DMSA therapy for children with autism spectrum disorders: Part A - Medical results
The positive soundscape project : a synthesis of results from many disciplines
This paper takes an overall view of ongoing findings from the Positive Soundscape Project, a large inter-disciplinary soundscapes study which is nearing completion. Qualitative fieldwork (soundwalks and focus groups) and lab-based listening tests have revealed that two key dimensions of the emotional response are calmness and vibrancy. In the lab these factors explain nearly 80% of the variance in listener response. Physiological validation is being sought using fMRI measurements, and these have so far shown significant differences in the response of the brain to affective and neutral soundscapes. A conceptual framework which links the key soundscape components and which could be used for future design is outlined. Metrics are suggested for some perceptual scales and possibilities for soundscape synthesis for design and user engagement are discussed, as are the applications of the results to future research and environmental noise policy
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