4,645 research outputs found
Discrete choice models of labour suppluy, behavioural microsimulation and the Spanish tax reform
In this paper, we demonstrate the potential of behavioural microsimulation models as powerful tools for the ex ante evaluation of public policies. The subject of our analysis is the impact of recent Spanish Income Tax reforms on efficiency and household and social welfare. We also analyze the likely effects of some basic income - flat tax and vital minimum - flat tax schemes. The analysis is carried out using a microsimulation model in which labour supply is explicitly taken into account. Instead of following the traditional continuous approach (Hausman 1981, 1985a, and 1985b), we estimate the direct utility function using the methodology proposed by Van Soest (1995). Our data come from a sample of Spanish individuals in the 1995 wave of the EC Household Panel. We show that in the Spanish case, the redistribution policies considered have only little impact on the efficiency of the economy. On the contrary, they strongly affect social welfare.microsimulation models ; evaluation of public policies
New floristic data of alien vascular plants from Sicily
New records of Commelina communis, Euphorbia hypericifolia, Melia azedarach, Nicotiana tabacum, and Xanthoceras sorbifolium are reported for the Sicilian flora
Study of the performance of the NA62 Small-Angle Calorimeter at the DANE Linac
The measurement of with 10% precision by the
NA62 experiment requires extreme background suppression. The Small Angle
Calorimeter aims to provide an efficient veto for photons flying at angles down
to zero with respect to the kaon flight direction. The initial prototype was
upgraded and tested at the Beam Test Facility of the DANE Linac at
Frascati. The energy resolution and the efficiency were measured and are
presented.Comment: 5 pages, 7 figure
Small-scale flows in SUMER and TRACE high-cadence co-observations
We report on the physical properties of small-scale transient flows observed
simultaneously at high cadence with the SUMER spectrometer and the TRACE imager
in the plage area of an active region. Our major objective is to provide a
better understanding of the nature of transient phenomena in the solar
atmosphere by using high-cadence imager and spectrometer co-observations at
similar spatial and temporal resolution. A sequence of TRACE Fe IX/X 171 A and
high-resolution MDI images were analysed together with simultaneously obtained
SUMER observations in spectral lines covering a temperature range from 10 000 K
to 1 MK. We reveal the existence of numerous transient flows in small-scale
loops (up to 30 Mm) observed in the plage area of an active region. These flows
have temperatures from 10 000 K (the low temperature limit of our observations)
to 250 000 K. The coronal response of these features is uncertain due to a
blending of the observed coronal line Mg X 624.85 A. The duration of the events
ranges from 60 s to 19 min depending on the loop size. Some of the flows reach
supersonic velocities. The Doppler shifts often associated with explosive
events or bi-directional jets can actually be identified with flows (some of
them reaching supersonic velocities) in small-scale loops. Additionally, we
demonstrate how a line-of-sight effect can give misleading information on the
nature of the observed phenomena if only either an imager or a spectrometer is
used.Comment: 7 pages, 6 figures, accepted by A&
Surface-enhanced Raman spectroscopy in 3D electrospun nanofiber mats coated with gold nanorods
Nanofibers functionalized by metal nanostructures and particles are exploited
as effective flexible substrates for SERS analysis. Their complex
three-dimensional structure may provide Raman signals enhanced by orders of
magnitude compared to untextured surfaces. Understanding the origin of such
improved performances is therefore very important for pushing nanofiber-based
analytical technologies to their upper limit. Here we report on polymer
nanofiber mats which can be exploited as substrates for enhancing the Raman
spectra of adsorbed probe molecules. The increased surface area and the
scattering of light in the nanofibrous system are individually analyzed as
mechanisms to enhance Raman scattering. The deposition of gold nanorods on the
fibers further amplifies Raman signals due to SERS. This study suggests that
Raman signals can be finely tuned in intensity and effectively enhanced in
nanofiber mats and arrays by properly tailoring the architecture, composition,
and light-scattering properties of the complex networks of filaments.Comment: 29 pages, 9 figures, 1 Tabl
Molecular and taxonomic characterization of a endophytic fungus isolated from Helleborus bocconei subsp. intermedius (Ranunculaceae)
A non-sporulating fungus was isolated from different organs of Helleborus bocconei subsp. intermedius (Ranunculaceae) endemic to southern Italy and Sicily, known for the traditional use of dried roots in the treatment of lung diseases of cattle and horses.
Molecular characterization of endophytic fungus based on the internal transcribed spacer (ITS) region of the rRNA gene sequences was done. The DNA sequence of full length ITS region of the studied fungus was a 100% match to that of Chaetomium strumarium strain dH 21642 (GenBank accession number JX280851.1). The morphological characters of colony and mycelium of this microfungus are reported here
Discrete choice models of labour suppluy, behavioural microsimulation and the Spanish tax reform
In this paper, we demonstrate the potential of behavioural microsimulation models as powerful tools for the ex ante evaluation of public policies. The subject of our analysis is the impact of recent Spanish Income Tax reforms on efficiency and household and social welfare. We also analyze the likely effects of some basic income - flat tax and vital minimum - flat tax schemes. The analysis is carried out using a microsimulation model in which labour supply is explicitly taken into account. Instead of following the traditional continuous approach (Hausman 1981, 1985a, and 1985b), we estimate the direct utility function using the methodology proposed by Van Soest (1995). Our data come from a sample of Spanish individuals in the 1995 wave of the EC Household Panel. We show that in the Spanish case, the redistribution policies considered have only little impact on the efficiency of the economy. On the contrary, they strongly affect social welfare.Dans cet article, on démontre le potentiel des modèles de microsimulation avec comportements dans l'évaluation ex ante des politiques publiques. Le sujet de notre analyse est l'impact sur l'efficacité et sur le bien-être des ménages, des réformes récentes de l'impôt sur les revenus implémentées en Espagne. On analyse aussi les effets de certains scénarios de réforme inspirés de la logique du revenu minimum - impôt linéaire. L'analyse est effectuée à l'aide d'un modèle de microsimulation avec réactions d'offre de travail. Au lieu de suivre l'approche traditionnelle à la Hausman (1981, 1985a, 1985b), on estime directement les paramètres de la fonction d'utilité en employant la méthodologie proposée par Van Soest (1995). Les données ont été récupérées à partir de la vague 1995 du Panel européen des ménages (ECHP). On démontre que, dans le cas espagnol, les politiques redistributives implémentées ont des effets mineurs sur l'efficacité économique, par contre, elles augmentent de façon importante le bien-être social
Multiclass scheduling algorithms for the DAVID metro network
Abstract—The data and voice integration over dense wavelength-division-multiplexing (DAVID) project proposes a metro network architecture based on several wavelength-division-multiplexing (WDM) rings interconnected via a bufferless optical switch called Hub. The Hub provides a programmable interconnection among rings on the basis of the outcome of a scheduling algorithm. Nodes connected to rings groom traffic from Internet protocol routers and Ethernet switches and share ring resources. In this paper, we address the problem of designing efficient centralized scheduling algorithms for supporting multiclass traffic services in the DAVID metro network. Two traffic classes are considered: a best-effort class, and a high-priority class with bandwidth guarantees. We define the multiclass scheduling problem at the Hub considering two different node architectures: a simpler one that relies on a complete separation between transmission and reception resources (i.e., WDM channels) and a more complex one in which nodes fully share transmission and reception channels using an erasure stage to drop received packets, thereby allowing wavelength reuse. We propose both optimum and heuristic solutions, and evaluate their performance by simulation, showing that heuristic solutions exhibit a behavior very close to the optimum solution. Index Terms—Data and voice integration over dense wavelength-division multiplexing (DAVID), metropolitan area network, multiclass scheduling, optical ring, wavelength-division multiplexing (WDM). I
Association between Resistin Levels and All-Cause and Cardiovascular Mortality: A New Study and a Systematic Review and Meta-Analysis.
CONTEXT: Studies concerning the association between circulating resistin and mortality risk have reported, so far, conflicting results.
OBJECTIVE: To investigate the association between resistin and both all-cause and cardiovascular (CV) mortality risk by 1) analyzing data from the Gargano Heart Study (GHS) prospective design (n=359 patients; 81 and 58 all-cause and CV deaths, respectively); 2) performing meta-analyses of all published studies addressing the above mentioned associations.
DATA SOURCE AND STUDY SELECTION: MEDLINE and Web of Science search of studies reporting hazard ratios (HR) of circulating resistin for all-cause or CV mortality.
DATA EXTRACTION: Performed independently by two investigators, using a standardized data extraction sheet.
DATA SYNTHESIS: In GHS, adjusted HRs per one standard deviation (SD) increment in resistin concentration were 1.28 (95% CI: 1.07-1.54) and 1.32 (95% CI: 1.06-1.64) for all-cause and CV mortality, respectively. The meta-analyses included 7 studies (n=4016; 961 events) for all-cause mortality and 6 studies (n=4,187: 412 events) for CV mortality. Pooled HRs per one SD increment in resistin levels were 1.21 (95% CI: 1.03-1.42, Q-test p for heterogeneity<0.001) and 1.05 (95% CI: 1.01-1.10, Q-test p for heterogeneity=0.199) for all-cause and CV mortality, respectively. At meta-regression analyses, study mean age explained 9.9% of all-cause mortality studies heterogeneity. After adjusting for age, HR for all-cause mortality was 1.24 (95% CI: 1.06-1.45).
CONCLUSIONS: Our results provide evidence for an association between circulating resistin and mortality risk among high-risk patients as are those with diabetes and coronary artery disease
A prototype large-angle photon veto detector for the P326 experiment at CERN
The P326 experiment at the CERN SPS has been proposed with the purpose of
measuring the branching ratio for the decay K^+ \to \pi^+ \nu \bar{\nu} to
within 10%. The photon veto system must provide a rejection factor of 10^8 for
\pi^0 decays. We have explored two designs for the large-angle veto detectors,
one based on scintillating tiles and the other using scintillating fibers. We
have constructed a prototype module based on the fiber solution and evaluated
its performance using low-energy electron beams from the Frascati Beam-Test
Facility. For comparison, we have also tested a tile prototype constructed for
the CKM experiment, as well as lead-glass modules from the OPAL electromagnetic
barrel calorimeter. We present results on the linearity, energy resolution, and
time resolution obtained with the fiber prototype, and compare the detection
efficiency for electrons obtained with all three instruments.Comment: 8 pages, 9 figures, 2 tables. Presented at the 2007 IEEE Nuclear
Science Symposium, Honolulu HI, USA, 28 October - 3 November 200
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