444 research outputs found
Radiation calculations for the ATLAS detector and experimental hall
This paper describes the calculations performed to characterise the radiation field in the ATLAS detector at the LHC and to design the shielding of the detector and experimental areas. After a short description of the ATLAS detector, the simulations made with the MC code FLUKA are described in some detail. The radiation fields calculated in the inner cavity, in the calorimeters, in the experimental cavern, in the shafts and in an external skyshine region are presented
Functional forms of socio-territorial inequities in breast cancer screening â A French cross-sectional study using hierarchical generalised additive models
To reduce the breast cancer burden, the French National Organised Breast Cancer Screening Programme (FNOBCSP) was implemented in 2004. The recommended participation rate has never been achieved and socio-territorial inequities in participation have been reported on several occasions. We investigated the functional forms and consistency of the relationships between neighbourhood deprivation, travel time to the nearest accredited radiology centre and screening uptake. We used two-level hierarchical generalised additive models in 8 types of territories classified by socio-demographic and economic factors. The first level was 368,201 women aged 50â72 invited to the 2013â2014 screening campaign in metropolitan France. They were nested in 41 dĂ©partements, the level of organisation of the FNOBCSP. The effect of travel time showed two main patterns: it was either linear (with participation decreasing as travel time increased) or participation first increased with increasing travel time to a peak around 5â15 min and decreased afterward. In nearly all types and dĂ©partements, the probability of participation decreased linearly with increasing deprivation. Territorial inequities in participation were more context-dependent and complex than social inequities. Inequities in participation represent a loss of opportunity for individuals who already have the worst cancer outcomes. Evidence-based public health policies are needed to increase the effectiveness and equity of breast cancer screening
Parametrization of semi-dynamical quantum reflection algebra
We construct sets of structure matrices for the semi-dynamical reflection
algebra, solving the Yang-Baxter type consistency equations extended by the
action of an automorphism of the auxiliary space. These solutions are
parametrized by dynamical conjugation matrices, Drinfel'd twist representations
and quantum non-dynamical -matrices. They yield factorized forms for the
monodromy matrices.Comment: LaTeX, 24 pages. Misprints corrected, comments added in Conclusion on
construction of Hamiltonian
Structures in BC_N Ruijsenaars-Schneider models
We construct the classical r-matrix structure for the Lax formulation of BC_N
Ruijsenaars-Schneider systems proposed in hep-th 0006004. The r-matrix
structure takes a quadratic form similar to the A_N Ruijsenaars-Schneider
Poisson bracket behavior, although the dynamical dependence is more
complicated. Commuting Hamiltonians stemming from the BC_N
Ruijsenaars-Schneider Lax matrix are shown to be linear combinations of
particular Koornwinder-van Diejen ``external fields'' Ruijsenaars-Schneider
models, for specific values of the exponential one-body couplings. Uniqueness
of such commuting Hamiltonians is established once the first of them and the
general analytic structure are given.Comment: 18 pages, gzip latex fil
Spin chains from dynamical quadratic algebras
We present a construction of integrable quantum spin chains where local
spin-spin interactions are weighted by ``position''-dependent potential
containing abelian non-local spin dependance. This construction applies to the
previously defined three general quadratic reflection-type algebras:
respectively non-dynamical, semidynamical, fully dynamical.Comment: 12 pages, no figures; v2: corrected formulas of the last sectio
Liquid/Liquid Extraction Kinetics of Eu(III) and Am(III) by Extractants Designed for the Industrial Reprocessing of Nuclear Wastes
Results about the kinetics of extraction of Eu(III) and Am(III) by extractants designed for the industrial reprocessing of nuclear wastes are reported. They were obtained using the rotating membrane cell (RMC) technique. Extraction and stripping kinetic rate constants were determined for various compositions of the aqueous and organic phases. The transfer was studied at liquid/liquid interfaces between an aqueous nitric acid solution and an organic solvent containing the diglycolamide extractant molecule N,N,NâČ,NâČ-tetra-n-octyl-diglycolamide (TODGA) or a mixture of the bipyridine molecule CyMe4BTBP with TODGA (the latter being used as a phase-transfer catalyst), dissolved in an aliphatic diluent. In some experiments, an aqueous ligand (a sulfonated bis triazinyl pyridine, SO3-Ph-BTP, or a PyTri-diol) was added to the aqueous phase as a stripping agent. The diffusion coefficients of Eu(III) and Am(III), which are key in the analysis of the kinetic data, were measured using the RMC and the closed capillary technique. Whenever possible, mechanisms are proposed to interpret the experimental results
An assessment of nitrification inhibitors to reduce nitrous oxide emissions from UK agriculture
A trial was conducted consisting of 14 experiments across sites in England of contrasting soil type and annual rainfall to assess the effectiveness of nitrification inhibitors (predominantly dicyandiamide (DCD) but limited assessment also of 3, 4-dimethylpyrazole phosphate (DMPP) and a commercial product containing two pyrazole derivatives) in reducing direct nitrous oxide (N _2 O) emissions from fertilizer nitrogen (N), cattle urine and cattle slurry applications to land. Measurements were also made of the impact on ammonia (NH _3 ) volatilization, nitrate (NO _3 ^â ) leaching, crop yield and crop N offtake. DCD proved to be very effective in reducing direct N _2 O emissions following fertilizer and cattle urine applications, with mean reduction efficiencies of 39, 69 and 70% for ammonium nitrate, urea and cattle urine, respectively. When included with cattle slurry a mean, non-significant reduction of 56% was observed. There were no N _2 O emission reductions observed from the limited assessments of the other nitrification inhibitors. Generally, there were no impacts of the nitrification inhibitors on NH _3 volatilization, NO _3 ^â leaching, crop yield or crop N offtake. Use of DCD could give up to 20% reduction in N _2 O emissions from UK agriculture, but cost-effective delivery mechanisms are required to encourage adoption by the sector. Direct N _2 O emissions from the studied sources were substantially lower than IPCC default values and development of UK country-specific emission factors for use in inventory compilation is warranted
Reflection -matrices related to Temperley-Lieb -matrices
The general solutions of the reflection equation associated with
Temperley-Lieb -matrices are constructed. Their parametrization is defined
and the Hamiltonians of corresponding integrable spin systems are given.Comment: 11 pages, no figures. References added and a few misprints corrected.
To appear in Theoretical and Mathematical Physics (2011
Comparison of codes assessing galactic cosmic radiation exposure of aircraft crew
The assessment of the exposure to cosmic radiation onboard aircraft is one of the preoccupations of bodies responsible for radiation protection. Cosmic particle flux is significantly higher onboard aircraft than at ground level and its intensity depends on the solar activity. The dose is usually estimated using codes validated by the experimental data. In this paper, a comparison of various codes is presented, some of them are used routinely, to assess the dose received by the aircraft crew caused by the galactic cosmic radiation. Results are provided for periods close to solar maximum and minimum and for selected flights covering major commercial routes in the world. The overall agreement between the codes, particularly for those routinely used for aircraft crew dosimetry, was better than ±20 % from the median in all but two cases. The agreement within the codes is considered to be fully satisfactory for radiation protection purpose
Restauration morpho-dynamique et redynamisation de la section court-circuitée du Rhin en aval du barrage de Kembs (projet INTERREG / EDF)
National audienceThe Upper Rhine River has been heavily impacted by channelization for flood protection and navigation, and then by damming for hydropower generation. In normal non flooding conditions, most of the flows are diverted in a canalized section whereas the regulated âold Rhineâ bypassed reach runs a minimum flow. Between Huningue and Neuf-Brisach, engineering works induced simplification and stabilization of the channel pattern from a formerly braiding sector to a single incised channel, hydrological modifications, bottom armouring due to bedload decrease, and thus ecological alterations. Two complementary and interdisciplinary projects have been initiated to restore alluvial morphodynamics: i) the international âINTERREG IV - Redynamisation of the old Rhineâ project (2009-2012) coordinated by the Alsace region, France; ii) the left bank âcontrolled erosionâ project launched by ElectricitĂ© de France (EDF) within Kembs hydroelectric station relicensing process since 2003-2004. The purpose of these projects is to evaluate the feasibility of an important hydro-morphological and ecological restoration plan on a 45 km long reach, through both field testing of bank erosion techniques at favourable locations, and artificial sediments input from right bank excavations. This will help define possible long term prospective scenarios, in order to restore sustainable sediment transport, morphodynamics variability and associated ecological functions. The study will involve historical analysis, hydro-morphological / hydraulic physical and numerical modelling, physical and ecological monitoring, and sociological aspectsLe Rhin alsacien-allemand a enregistrĂ© de profondes modifications morphologiques et hydrologiques Ă la suite de sa correction et de sa rĂ©gularisation pour la protection contre les crues et la navigation, puis aprĂšs la construction de barrages hydro-Ă©lectriques. Les amĂ©nagements rĂ©alisĂ©s entre Huningue et Neuf-Brisach ont engendrĂ© une simplification et une stabilisation du style fluvial. Un fleuve en tresses a cĂ©dĂ© la place Ă un chenal unique incisĂ©. Le fond de chenal est devenu pavĂ© Ă cause dâune diminution des apports de charge de fond et des altĂ©rations Ă©cologiques ont Ă©tĂ© observĂ©es (simplification des habitats aquatiques et riverains). Deux projets complĂ©mentaires et interdisciplinaires ont Ă©tĂ© engagĂ©s afin de restaurer une dynamique des formes alluviales : i) le projet international INTERREG IV â Redynamisation du Vieux Rhin (2009-2012) sous lâimpulsion de la rĂ©gion Alsace ; ii) le projet dâĂ©rosion maitrisĂ©e des berges de la rive gauche conduit par ElectricitĂ© de France (EDF) dans le cadre du renouvellement de la concession de lâamĂ©nagement de Kembs. Lâobjectif des deux projets est de dĂ©finir un plan de restauration hydro-morphologique et Ă©cologique conduisant Ă la redynamisation dâun tronçon de 45 km. LâĂ©tude repose sur une analyse historique, lâexploitation de modĂšles Ă la fois physiques et numĂ©riques, et les suivis morphologiques in situ dâune recharge artificielle en sĂ©diments et dâĂ©rosions de berge contrĂŽlĂ©es. Ces Ă©tudes de faisabilitĂ© sont complĂ©tĂ©es par des analyses Ă©cologique et sociologique pour apprĂ©cier lâimpact socio-environnemental de ces projets
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