1,010 research outputs found
Broad-band X-ray analysis of local mid-infrared selected Compton-thick AGN candidates
The estimate of the number and space density of obscured AGN over cosmic time
still represents an open issue. While the obscured AGN population is a key
ingredient of the X-ray background synthesis models and is needed to reproduce
its shape, a complete census of obscured AGN is still missing. Here we test the
selection of obscured sources among the local 12-micron sample of Seyfert
galaxies. Our selection is based on a difference up to three orders of
magnitude in the ratio between the AGN bolometric luminosity, derived from the
spectral energy distribution (SED) decomposition, and the same quantity
obtained by the published XMM-Newton 2-10 keV luminosity.
The selected sources are UGC05101, NGC1194 and NGC3079 for which the
available X-ray wide bandpass, from Chandra and XMM-Newton plus NuSTAR data,
extending to energies up to ~30-45 keV, allows us an accurate determination of
the column density, and hence of the true intrinsic power.
The newly derived NH values clearly indicate heavy obscuration (about 1.2,
2.1 and 2.4 x10^{24} cm-2 for UGC05101, NGC1194 and NGC3079, respectively) and
are consistent with the prominent silicate absorption feature observed in the
Spitzer-IRS spectra of these sources (at 9.7 micron rest frame). We finally
checked that the resulting X-ray luminosities in the 2-10 keV band are in good
agreement with those derived from the mid-IR band through empirical L_MIR-L_X
relations.Comment: 14 pages, 6 figures, accepted for publication in MNRA
Searching with Friends
We study how active labor market policies affect the exchange of information and support among jobseekers. Leveraging a unique social network survey in Ethiopia, we find that a randomized job-search assistance intervention reduces information sharing and support between treated jobseekers and their active job-search partners. Due to lower job-search support, untreated individuals search less and, suggestively, have worse employment outcomes. These results are explained by a model of networks where unemployed individuals form job-search partnerships to exploit the complementarities of job search. These partnerships are broken if policy creates inequality in the access to information about job vacancies
First record of Ozognathus cornutus (LeConte, 1859) (Coleoptera Ptinidae) from Sardinia, Italy.
Ozognathus cornutus (LeConte, 1859) is recorded on the invasive alien tree Robinia pseudocacia L. (Fabaceae) in an urban area in Italy. The species has already been reported in two other Italian regions, but this is the first record for the Sardinian fauna. Due to the great adaptability of this alien species and the increasingly cosmopolitan trend, we suggest monitoring it with caution for early detection and to plan an appropriate rapid management response
Efficient second harmonic generation from thin films of V-shaped benzo[b]thiophene based molecules
We have designed an original approach for efficient Second Harmonic Generation of tailored V-shape benzo[b]thiophene molecular systems enabling versatile and flexible one-step, dry and technologically friendly thin film processing. The designed moieties show χ(2) values at least as high as the reference LiNbO3 single crystal, without poling processing and matching the constrains of integrated optical configuration for nonlinear optical devices. This may open the way to a new class of organic materials exploitable for photonic applications
Innovation Technology to Empower Safety, Health and Welfare in Agriculture and Agro-food Systems
Abstract The level of the vacuum in machine milking is one of the principal parameters which influence the integrity of the tissues and the milk quality. Many studies have shown that while raising the level of the vacuum increases the speed of milk emission, it can also generate congestion in the teat, formation of oedema, increase in residual milk and in the number of somatic cells. Thus milking should be performed with the lowest possible level of vacuum which is compatible with not excessively prolonging milking time. In Italy the vacuum level is unjustifiably high -on average 42 -46 kPa-while in other European countries the usually level is 4-5 kPa lower. In order to define the milking techniques which best satisfy the physiological needs of dairy sheep, we have compared milking performances at a low vacuum level (28 kPa) and at a standard level (42 kPa). The effects of the working conditions were evaluated by analyzing the milk emission curves and the vacuum fluctuations registered in the milkline and in the short milk tube. Results showed that using a vacuum of 28 kPa increased the latency time, reduced both average and peak milk flow, and increased the average milking time per head by 17%. The reduction of vacuum did not produce significant variations in vacuum fluctuations in the short milk tube (10.4 kPa at 28 kPa and 9.0 kPa at 42 kPa) and also in the milkline where the vacuum fluctuations were less than 2 kPa
Far UV responsivity of commercial silicon photodetectors
Abstract Responsivity measurements have been performed on commercial silicon photodetectors in the UV range 200–400 nm. The microstrip and pixel detectors have been reverse biased in fully depleted condition (more than 25 V reverse bias) and in partially depleted condition (5 V reverse bias). We have also performed measurements in back illumination geometry, of particular interest in most industrial applications. Promising results obtained with commercial photodetectors in the UV range in terms of photocurrent stability and sensitivity open a variety of applications
Opioid overdose risk during and after drug treatment for heroin dependence: An incidence density case–control study nested in the VEdeTTE cohort
Introduction and Aims: To corroborate protective effects of a range of drug treatment modalities against overdose mortality risk. Design and Methods: Nested case–control study, with incidence density sampling, selecting controls retrospectively at each case event. Cases and controls came from a sub-cohort of opioid-dependent patients (n = 4444) from two Italian regions (Lazio and Piedmont). From 1998 to 2005, there were 91 overdose deaths (cases) matched to 352 controls. The primary outcome was overdose mortality and the primary exposure was drug treatment: opioid agonist treatment (OAT), opioid detoxification, residential community, psychosocial and other pharmacological treatment. Conditional logistic regression models generated intervention effects comparing mortality risk in and out of treatment, adjusting for confounding variables. Results: Overall, drug treatment reduced overdose mortality risk by 80% [adjusted odds ratio (AOR) 0.18, 95% confidence interval (CI) 0.10–0.33, P < 0.001] compared to being out of treatment. There was a particularly strong protective effect of OAT on overdose mortality (AOR 0.08, 95% CI 0.03–0.23, P < 0.001) compared to being out of treatment. There was evidence of a substantially elevated risk of overdose in the first month of leaving treatment (AOR 23.50, 95% CI 7.84–70.19, P < 0.001) compared to being in treatment. Discussion and Conclusions: The nested case–control design strengthened earlier findings that OAT in Italy has strong protective effects on overdose mortality risk, much stronger than has been previously seen in other Western European settings
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