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Measurement of the inclusive electron spectrum from B meson decays and determination of |Vub|
No full textSearching for Fractal Structures in the Universal Steenrod Algebra at Odd Primes
No full textUnlike the p = 2 case, the universal Steenrod algebra Q(p) at odd primes does not have a fractal structure that preserves the length of
monomials. Nevertheless, when p is odd, we detect inside Q(p) two different families of nested subalgebras, each isomorphic (as length-graded algebras) to the respective starting element of the sequence
Modeling university student satisfaction: the case of the humanities and social studies degree programs
No full textThis paper investigates the problem of modeling students’ satisfaction ratings of various aspects of academic teaching in six humanities departments at University of Naples Federico II. In particular, we propose a strategy for analyzing data from the annual survey used to collects feedback from students across the university. The statistical procedure for this data analysis consists of two steps. First, the random forest method is fitted to the data to identify important predictors of student global satisfaction. Second, the probability distribution of student satisfaction ratings is estimated by fitting a mixture distribution with varying parameters (denoted the CUB model). The random forest methods shows that students’ interest in the course topics, together with the course objectives and teaching tools, are the main determinants of student satisfaction. Inclusion of these covariates in the CUB models confirms their dominant role in differentiating students’ evaluations of degree courses
Responsible Gambling Strategies for Internet Gambling: An Empirical Investigation into the Italian Gambling Market
No full textThe aim of this study is to analyse, in the Italian sports betting sector, the impact of Internet gambling on the level of consumption of gambling products and the responsible gambling strategies adopted by the on line gambling operators. From the methodological viewpoint the research work has been organised into two phases. In the first phase, an empirical investigation has been carried out on a sample of Italian consumers directed towards measuring the impact that the use of the Internet has on the volume of bets made on sports events. In the second phase, an analytical work has been performed on the on line gambling websites of the main operators of the Italian sports betting market, directed towards examining the measures adopted for promoting responsible gambling. The results of the empirical research indicate, on the one hand, that in the Italian market, as has happened in other national gambling markets, the legalization of on line sports betting may determine an increase in the level of consumption of gambling products and, thus, in the potential risks of excessive gambling; and, on the other hand, that the normative approach adopted in the Italian gambling market, based on a ‘concession model’ which provides for a strong public control of the gambling operators, has favoured a widespread adoption by the on line betting companies of an articulated series of measures aimed towards harm minimisation in Internet gambling. Thus, the findings of this study contribute towards the economic-managerial literature on the theme of firms’ social responsibility by providing important insights for gambling firms and public policy makers regarding the responsible gambling strategies for Internet gambling adoptable in the markets, such as the Italian one, in which on line gambling is fully regulated
Parallel Plate Channels for Latent Heat Thermal Energy Storages
No full textLately TES systems for thermal applications, such as space
and water heating, air-conditioning, cooling, etc. have received
much attention. In TES system, energy is stored by changing
the temperature of a storage medium or employing the latent
heat of Phase Change Material (PCM). For a TES system, it is
important to have a charging velocity rather high, because for
an assigned system size, it is possible to obtain greater amount
of stored energy in less time. Therefore, the heat transfer
between the working fluid and the TES system should be
improved by increasing the surface exchange area.
In the present work a computational investigation on
thermal energy storage system using Phase Change Material
(PCM) is accomplished. The system is a set of different parallel
plates, half of them are filled with PCM and in the others the
working fluid, air, flows. Various configurations for different
channels per unit of length (CPL) are investigated. A
comparison between a direct model and a porous medium
model is carried out. The porous medium is modeled with the
Darcy-Forchheimer law. Numerical simulations are carried out
using the Ansys-Fluent code for the direct model with 2n
channels for direct and equivalent porous medium
Grey:white matter ratio at diagnosis and the risk of 10-year multiple sclerosis progression
No full textBackground and purpose: Grey matter (GM) and white matter (WM) are both affected in multiple sclerosis (MS). WM is predominantly involved in inflammatory demyelination of relapsing–remitting MS (RRMS), whereas GM is predominantly involved in neurodegenerative processes of secondary progressive MS. Thus, we investigated the ratio between GM and WM volumes in predicting MS evolution. Methods: The present 10-year retrospective cohort study included 149 patients with newly-diagnosed RRMS, undergoing magnetic resonance imaging for segmentation and brain volumetry. The ratio between GM and normal-appearing WM (NAWM) volumes was calculated for each subject. Outcome measures of interest were Expanded Disability Status Scale (EDSS) progression, reaching EDSS 4.0 and conversion to secondary progressive (SP) MS. Results: During a period of 10.6 ± 2.4 years, a median 1.5 EDSS progression was observed (range 0–5.5), 54 subjects (36.2%) reached EDSS 4.0 and 30 subjects (20.1%) converted to SP. With ordinal logistic regression models, EDSS progression was associated with GM:NAWM ratio (coefficient, −2.918; 95% CI, −4.739–1.097). With Cox regression models, subjects with higher GM:NAWM ratio at diagnosis had a 90% lower rate of reaching EDSS 4.0 (hazard ratio, 0.111; 95% CI, 0.020–0.609) and of converting to secondary progressive MS (hazard ratio, 0.017; 95% CI, 0.001–0.203) compared with subjects with lower GM:NAWM ratio. Conclusions: The GM:NAWM ratio is a predictor of disability progression and of SP conversion in subjects with newly diagnosed RRMS, suggesting that GM and NAWM are variably affected in relation to disease evolution from the early phases of MS. © 2016 EA
Treatment by fining agents of red wine affected by phenolic off-odour
No full textAlthough phenolic off-odour is very detrimental for red wine quality, there is a lack of easy-to-use methods
able to decrease the levels of the responsible compounds 4-ethylphenol (4-EP) and 4-ethylguaiacol (4-EG) and to
improve the sensory quality of the contaminated wines. To this aim, an alternative use of fining agents (activated charcoal, PVPP and zeolite) was evaluated. Two levels of ethylphenol contamination were considered: a naturally low contaminated red wine and the same wine spiked with 4-EP and 4-EG. The impact of the treatments on desirable aroma volatiles, polyphenols and colour was also evaluated. The effectiveness in diminishing the intensity of the phenolic off-odour was assessed by descriptive sensory analysis.
The activated charcoal and PVPP significantly decreased the concentrations of 4-ethylguaiacol and 4-ethylphenol in
the naturally contaminated wine, while none of the tested fining agent was effective in the spiked one. Polyphenols
and colour were slightly affected, to the same extent for the two treatments. Charcoal and PVPP additions negatively impacted the concentration of the aroma volatiles, especially esters, with the activated charcoal achieving a higher decrease. The sensory outcome of both treatments was the decrease in the intensity of phenolic off-odour, with charcoal achieving a higher decrease. Interestingly, in spite of the decrease in esters, also a significant increase in the intensity of “red fruit” odour occurred