4,134 research outputs found

    A systematic review of school-based alcohol and other drug prevention programs

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    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

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    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

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    The Fermi Large Area Telescope (LAT) is currently the most important facility for investigating the GeV γ\gamma-ray sky. With Fermi LAT more than three thousand γ\gamma-ray sources have been discovered so far. 1144 (40%\sim40\%) of the sources are active galaxies of the blazar class, and 573 (20%\sim20\%) 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 γ\gamma-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.

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    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

    Optical counterparts of undetermined type γ\gamma-ray Active Galactic Nuclei with blazar-like Spectral Energy Distributions

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    During its first four years of scientific observations, the Fermi Large Area Telescope (Fermi-LAT) detected 3033 γ\gamma-ray sources above a 4σ\sigma significance level. Although most of the extra-Galactic sources are active galactic nuclei (AGN) of the blazar class, other families of AGNs are observed too, while a still high fraction of detections (30%\sim 30\%) remains with uncertain association or classification. According to the currently accepted interpretation, the AGN γ\gamma-ray emission arises from inverse Compton (IC) scattering of low energy photons by relativistic particles confined in a jet that, in the case of blazars, is oriented very close to our line of sight. Taking advantage of data from radio and X-ray wavelengths, which we expect to be produced together with γ\gamma-rays, providing a much better source localization potential, we focused our attention on a sample of γ\gamma-ray Blazar Candidates of Undetermined Type (BCUs), starting a campaign of optical spectroscopic observations. The main aims of our investigation include a census of the AGN families that contribute to γ\gamma-ray emission and a study of their redshift distribution, with the subsequent implications on the intrinsic source power. We furthermore analyze which γ\gamma-ray properties can better constrain the nature of the source, thus helping in the study of objects not yet associated with a reliable low frequency counterpart. In this communication we report on the instruments and techniques used to identify the optical counterparts of γ\gamma-ray sources, we give an overview on the status of our work, and we discuss the implications of a large scale study of γ\gamma-ray emitting AGNs.Comment: 9 pages, 2 figures, proceedings of the 10th Serbian Conference on Spectral Line Shapes in Astrophysics. JOAA, accepte

    The Use and Perception of ICT Among Educators: The Italian Case

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    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

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    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

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    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
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