6,366 research outputs found
Measurement of the Higgs properties at CMS
The studies of the properties of the recently found boson performed by CMS are presented. The analyses reported here use the data sample of 5.1 fbâ1 at âs = 7TeV and 12.1 fbâ1 at âs = 8TeV delivered by LHC and collected by the CMS experiment. The background-only hypothesis is excluded with a 6.9Ï significance. The mass of the new boson is measured to be 125.8 ± 0.4(stat) ± 0.4(syst) GeV/c2, combining the diphoton and four lepton channels. Several spin and intrinsic parity hypotheses are tested. The SM coupling structure is tested combining the measurements in all the considered final states, and a good Agreement is found with the Standard Model predictions
A new formulation of the Gram-Charlier method: Performance for fitting non-normal distribution
The Gram-Charlier expansion was derived in an attempt to express non-normal densities as infinite series involving the normal density and its derivatives, using the moments data as input terms. In classic Gram-Charlier expansion
the random variable is standardized, so that the Gaussian parameters are Always fixed and referred to the mean equal to zero and to the standard deviation equal to one. This assumption seems to be too strong. An improvement of
Gram-Charlier expansion was obtained by an optimization process, directed to choose new values of Gaussian parameters. In order to check the performance of the new approach, an estimate of the gamma probability density function was calculated. Two probability density functions, characterized by a different degree of skewness and kurtosis, were considered. The study has shown that in comparison with the classic assumption, the new one always gives the best results in terms of probability density function reproducibility and allows the best evaluation of the input moments. Further the comparison between estimated moments of order higher than the input ones and the theoretical moments shows a good reproduction. Finally the method seems to suggest that a less restrictive condition can be considered respect to the usual convergence criterium of the Gram-Charlier expansion
Narrow beam dosimetry for high-energy hadrons and electrons
Organ doses and effective dose were calculated with the latest version of the Monte Carlo transport code FLUKA in the case of an anthropomorphic mathematical model exposed to monoenergetic narrow beams of protons, pions and electrons in the energy range 10塉 400 GeV. The target organs considered were right eye, thyroid, thymus, lung and breast. Simple scaling laws to the calculated values are given. The present data and formula should prove useful for dosimetric estimations in case of accidental exposures to high-energy beams
Estimation of fluence rate and absorbed dose rate due to gas bremsstrahlung from electron storage rings
Abstract Bremsstrahlung produced in electron storage rings by interactions with residual gas has been studied in the energy range 100â1000 MeV using the PLUKA code. Photon spectra and quantitative estimates of fluence rate and tissue absorbed dose rate are given. Simple equations are proposed for the fluence rate and the absorbed dose rate according to the results obtained
DEFINITION OF NOVEL HEALTH AND AIR POLLUTION INDEX BASED ON SHORT TERM EXPOSURE AND AIR CONCENTRATION LEVELS
Health impact assessment has become important in the development of air quality policies and in finding the relationships
between pollutants concentration and health effects. In our work we presented a novel index able to evaluate the effects on the
human exposure caused by ambient air pollution in urban areas. The index is able to link both health risk factors and pollutants
levels. The indexes is of additive type and is composed by two terms: the former is based on pollutants concentration and is
connected with EPA air quality index (AQI), while the latter is composed by an adimensional term based on the exposure levels. We
tested the methodology using PM10 as studied pollutants. The spatial and temporal variation of its health impact was evaluated by
means of index maps applying the above methodology in the city of Rome during three selected episodes. Our study shows index
maps for all episodes linked to population and to pollutants
Modelling the influence of shielding on physical and biological organ doses.
Distributions of "physical" and "biological" dose in different organs were calculated by coupling the FLUKA MC transport code with a geometrical human phantom inserted into a shielding box of variable shape, thickness and material. While the expression "physical dose" refers to the amount of deposited energy per unit mass (in Gy), "biological dose" was modelled with "Complex Lesions" (CL), clustered DNA strand breaks calculated in a previous work based on "event-by-event" track-structure simulations. The yields of complex lesions per cell and per unit dose were calculated for different radiation types and energies, and integrated into a version of FLUKA modified for this purpose, allowing us to estimate the effects of mixed fields. As an initial test simulation, the phantom was inserted into an aluminium parallelepiped and was isotropically irradiated with 500 MeV protons. Dose distributions were calculated for different values of the shielding thickness. The results were found to be organ-dependent. In most organs, with increasing shielding thickness the contribution of primary protons showed an initial flat region followed by a gradual decrease, whereas secondary particles showed an initial increase followed by a decrease at large thickness values. Secondary particles were found to provide a substantial contribution, especially to the biological dose. In particular, the decrease of their contribution occurred at larger depths than for primary protons. In addition, their contribution to biological dose was generally greater than that of primary protons
Infering Air Quality from Traffic Data using Transferable Neural Network Models
This work presents a neural network based model for inferring air quality from traffic measurements.
It is important to obtain information on air quality in urban environments in order to meet legislative and policy requirements. Measurement equipment tends to be expensive to purchase and maintain. Therefore, a model based approach capable of accurate determination of pollution levels is highly beneficial.
The objective of this study was to develop a neural network model to accurately infer pollution levels from existing data sources in Leicester, UK.
Neural Networks are models made of several highly interconnected processing elements. These elements process information by their dynamic state response to inputs. Problems which were not solvable by traditional algorithmic approaches frequently can be solved using neural networks.
This paper shows that using a simple neural network with traffic and meteorological data as inputs, the air quality can be estimated with a good level of generalisation and in near real-time.
By applying these models to links rather than nodes, this methodology can directly be used to inform traffic engineers and direct traffic management decisions towards enhancing local air quality and traffic management simultaneously.Universidad de MĂĄlaga. Campus de Excelencia Internacional AndalucĂa Tech
Tablet splitting in elderly patients with dementia: The case of quetiapine
Quetiapine is an atypical antipsychotic approved for treating schizophrenia, bipolar depression, and mania but is frequently used in an off-label manner to control the behavioral and psychological symptoms of dementia in elderly patients with dementia. Due to the need to personalize doses for elderly patients with dementia, quetiapine tablet manipulation is widespread in hospital settings, long-term care facilities, and patient homes. The aim of this study was to assess the impact of the different splitting techniques on quetiapine fumarate tablets by analysing the obtained sub-divided tablets and to discuss compliance with the European Pharmacopoeia limits on whole and split tablets. Quetiapine fumarate tablets of two dose strengths were taken at random (in a number able to assure a power of 0.8 during statistical comparison) and were split with a kitchen knife or tablet cutter. The weight and the drug content were determined for each half tablet. The obtained data were compared to the European Pharmacopoeia limits. The differences between the different splitting techniques were statistically tested. Data showed that split tablets, independently of the dose strength and the technique employed, were not compliant with the European Pharmacopoeia specifications for both entire and subdivided tablets in terms of weight and content uniformity. Thus, such a common practice could have potential effects on treatment efficacy and toxicity, especially when also considering the fragility of the elderly target population in which polypharmacotherapy is very common. These results indicate a compelling need for flexible quetiapine formulations that can assure more accurate dose personalization
The hadronic models for cosmic ray physics: the FLUKA code solutions
FLUKA is a general purpose Monte Carlo transport and interaction code used
for fundamental physics and for a wide range of applications. These include
Cosmic Ray Physics (muons, neutrinos, EAS, underground physics), both for basic
research and applied studies in space and atmospheric flight dosimetry and
radiation damage. A review of the hadronic models available in FLUKA and
relevant for the description of cosmic ray air showers is presented in this
paper. Recent updates concerning these models are discussed. The FLUKA
capabilities in the simulation of the formation and propagation of EM and
hadronic showers in the Earth's atmosphere are shown.Comment: 8 pages, 9 figures. Invited talk presented by M.V. Garzelli at
ISVHECRI2006, International Symposium on Very High Energy Cosmic Rays,
Weihai, China, August 15 - 22 200
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