4,232 research outputs found
A systematic review of school-based alcohol and other drug prevention programs
Background: Alcohol use in adolescents constitutes a major public health concern. Europe is the heaviest drinking
region of the world. Several school-based alcohol prevention programs have been developed but it is not clear whether
they are really effective. The present study was aimed at identifying the typology with the best evidence of effectiveness
in European studies. Methods: A systematic search of meta-analyses and/or randomized controlled trials (RCTs) on interventions
school-based prevention programs aimed at preventing alcohol consumption or changing the attitudes to consume
alcohol. Results: A meta-analysis published in 2011 and 12 RCTs more recently published were identified. The
meta-analysis evaluated 53 RCTs but only 11.3% of them were conducted in Europe. Globally, 23 RCTs (43.4%) showed
some evidence of effectiveness, and 30 RCTs (56.6%) did not find significant difference between the groups. According
to the conclusions of the meta-analysis, the Unplugged program should be considered as a practice option in Europe.
Among the other 12 RCTs, 42% were conducted in Europe. Globally, 7 studies (58.3%) achieved positive results, and 5
studies (41.7%) did not find significant differences or produced a mixed pattern of results. Three of the 5 European trials
(60%) used the Unplugged program with positive results. Conclusion: Even if further studies should be conducted to confirm
these results, Unplugged appears to be the prevention project with the best evidence of effectiveness in European
studies
Book Reviews
Obra ressenyada: Leonor RUIZ GURILLO ; Xose A. PADILLA GARCÍA, Dime cómo ironizas y te diré quién eres. Una aproximación pragmática a la ironía. Frankfurt am Main: Peter Lang, 2009
Blazar Flaring Patterns (B-FlaP): Classifying Blazar Candidates of Uncertain type in the third Fermi-LAT catalog by Artificial Neural Networks
The Fermi Large Area Telescope (LAT) is currently the most important facility
for investigating the GeV -ray sky. With Fermi LAT more than three
thousand -ray sources have been discovered so far. 1144 () of
the sources are active galaxies of the blazar class, and 573 () are
listed as Blazar Candidate of Uncertain type (BCU), or sources without a
conclusive classification. We use the Empirical Cumulative Distribution
Functions (ECDF) and the Artificial Neural Networks (ANN) for a fast method of
screening and classification for BCUs based on data collected at -ray
energies only, when rigorous multiwavelength analysis is not available. Based
on our method, we classify 342 BCUs as BL Lacs and 154 as FSRQs, while 77
objects remain uncertain. Moreover, radio analysis and direct observations in
ground-based optical observatories are used as counterparts to the statistical
classifications to validate the method. This approach is of interest because of
the increasing number of unclassified sources in Fermi catalogs and because
blazars and in particular their subclass High Synchrotron Peak (HSP) objects
are the main targets of atmospheric Cherenkov telescopes.Comment: 18 pages, 17 figures, accepted for publication on MNRA
Updated status of Anostraca, Notostraca and Spinicaudata (Crustacea Branchiopoda) in Sicily (Italy): review and new records.
A survey on distribution, phenology and status of large branchiopod crustaceans (Branchiopoda:
Anostraca, Notostraca, Spinicaudata) in Sicily and in circum-Sicilian islands was carried out
from autumn 2000 to winter 2004/2005 with the purpose of providing an organised contribution to
the knowledge of the distribution of these crustaceans in the region. Data from literature on Sicilian
large branchiopods has been briefly reviewed, and field surveys allowed us to add new data on their
actual consistency in the area. Current Sicilian large branchiopod fauna is characterised by a low
species richness and diversity, having possibly been impoverished by the high anthropic impact
which has interested the Sicilian wetlands.
The need for further surveys directed towards getting the knowledge necessary in order to correctly
understand and manage temporary pools, the elective habitat of a rich and peculiar biota
whose large branchiopods are “flagship species”, is stressed
The Use and Perception of ICT Among Educators: The Italian Case
Abstract When observing the impact of ICT on education, it's possible to distinguish two main areas of interest: how the ICTs are integrated in the educational strategies by teachers and students and how they are used by the students in activities that interfere with the educational process. The purpose of this study was to investigate the school-related uses, perceptions and representations of ICTs among primary and secondary school educators. More specifically, the research focused on the differences in ICT usage among the educators and their opinions on how ICTs are employed by the students, and what is the diffusion of problems connected with ICT misuse among their students. A sample of 796 educators from all over Italy answered to an online questionnaire composed of three parts, assessing their ICT skills, their perception of ICT use in school and their perception of the risks connected with ICT use. Four patterns of ICT use are found among the educators, going from highly skilled users to insecure users. These groups differ in their propensity to using ICTs in their teaching. On the whole, the sample highlighted a request for additional training on ICT use, and a wide diffusion of problems such as Internet addiction or cyberbullying in all the school levels, primary, middle and upper-school
Spectral properties of the narrow-line region in Seyfert galaxies selected from the SDSS-DR7
Although the properties of the narrow-line region (NLR) of active galactic
nuclei(AGN) have been deeply studied by many authors in the past three decades,
many questions are still open. The main goal of this work is to explore the NLR
of Seyfert galaxies by collecting a large statistical spectroscopic sample of
Seyfert 2 and Intermediate-type Seyfert galaxies having a high signal-to-noise
ratio in order to take advantage of a high number of emission-lines to be
accurately measured. 2153 Seyfert 2 and 521 Intermediate-type Seyfert spectra
were selected from Sloan Digital Sky Survey - Data Release 7 (SDSS-DR7) with a
diagnostic diagram based on the oxygen emission-line ratios. All the
emission-lines, broad components included, were measured by means of a
self-developed code, after the subtraction of the stellar component. Physical
parameters, such as internal reddening, ionization parameter, temperature,
density, gas and stellar velocity dispersion were determined for each object.
Furthermore, we estimated mass and radius of the NLR, kinetic energy of the
ionized gas, and black-hole accretion rate. From the emission-line analysis and
the estimated physical properties, it appears that the NLR is similar in
Seyfert 2 and Intermediate-Seyfert galaxies. The only differences, lower
extinction, gas kinematics in general not dominated by the host galaxy
gravitational potential and higher percentage of [O III]5007 blue asymmetries
in Intermediate-Seyfert can be ascribed to an effect of inclination of our line
of sight with respect to the torus axis.Comment: Accepted for publication in MNRA
Optical Emission Lines and the X-Ray Properties of Type 1 Seyfert Galaxies
In this contribution we report on the study of the optical emission lines and
X-ray spectra of a sample of Type 1 AGNs, collected at the Sloan Digital Sky
Survey database and observed by the XMM Newton satellite. Exploiting the
different instruments carried onboard XMM, we identify the spectral components
of the soft and hard energy bands (in the range from 0.3 keV up to 10 keV). The
properties of the X-ray continuum and of the Fe Kalpha line feature are
investigated in relation to the optical broad emission line profiles and
intensity ratios. The resulting picture of emission, absorption and reflection
processes is interpreted by means of a BLR structural model that was developed
on the basis of independent optical and radio observations.Comment: 6 pages, 3 figures, Proceedings of the VIII Serbian Conference on
Spectral Line Shapes in Astrophysics, accepted for publication on Baltic
Astronomy. Corrected typos in V
The Relation between Nuclear Activity and Stellar Mass in Galaxies
The existence of correlations between nuclear properties of galaxies, such as
the mass of their central black holes, and larger scale features, like the
bulge mass and luminosity, represent a fundamental constraint on galaxy
evolution. Although the actual reasons for these relations have not yet been
identified, it is widely believed that they could stem from a connection
between the processes that lead to black hole growth and stellar mass assembly.
The problem of understanding how the processes of nuclear activity and star
formation can affect each other became known to the literature as the
Starburst-AGN connection. Despite years of investigation, the physical
mechanisms which lie at the basis of this relation are known only in part. In
this work, we analyze the problem of star formation and nuclear activity in a
large sample of galaxies. We study the relations between the properties of the
nuclear environments and of their host galaxies. We find that the mass of the
stellar component within the galaxies of our sample is a critical parameter,
that we have to consider in an evolutionary sequence, which provides further
insight in the connection between AGN and star formation processes.Comment: 13 pages, 10 figures, accepted for publication on MNRAS. Reference to
the mass derivation procedure correcte
- …