Perceptions about alcohol use during pregnancy in France, Portugal and Spain: a cross-cultural qualitative study

info:eu-repo/semantics/publishedVersio

The swansong in context: long-timescale X-ray variability of NGC 4051

On 9-11 May 1998, the highly-variable, low luminosity Seyfert 1 galaxy NGC4051 was observed in an unusual low flux state by BeppoSAX (Guainazzi et al. 1998) RXTE and EUVE. We present fits of the 4-15 keV RXTE spectrum and BeppoSAX MECS spectrum obtained during this observation, which are consistent with the interpretation that the source had switched off, leaving only the spectrum of pure reflection from distant cold matter. We place this result in context by showing the X-ray lightcurve of NGC4051 obtained by our RXTE monitoring campaign over the past two and a half years, which shows that the low state lasted for ~150 days before the May observations (implying that the reflecting material is > 10^17 cm from the continuum source) and forms part of a lightcurve showing distinct variations in long-term average flux over timescales > months. We show that the long-timescale component to X-ray variability is intrinsic to the primary continuum and is probably distinct from the variability at shorter timescales, possibly associated with variations in the accretion flow of matter onto the central black hole. As the source approaches the low state, the variability process becomes non-linear. NGC4051 may represent a microcosm of all X-ray variability in radio quiet active galactic nuclei (AGNs), displaying in a few years a variety of flux states and variability properties which more luminous AGNs may pass through on timescales of decades to thousands of years.Comment: 5 pages, accepted for publication in MNRA

Correlation among job-induced stress, overall well-being, and cardiovascular risk in Italian workers of logistics and distribution

Introduction: Work-related stress is an occupational risk that has been linked to the development of cardiovascular disease (CVD). While previous studies have explored this association in various work contexts, none have focused specifically on logistics and distribution personnel. These workers may be exposed to significant job stress, which potentially increases the risk of CVD. Methods: In this study, we aimed to examine the relationship between work-related stress and cardiovascular risk in a sample of 413 healthy workers of a logistics and distribution company. To assess work-related stress and cardiovascular risk, we used the organisational well-being questionnaire proposed by the Italian National Anti-Corruption Authority, the Framingham Heart Study General Cardiovascular Disease (CVD) Risk Prediction Score and the WHO General Wellbeing Index (WHO-5). Results: Our results revealed that individuals with low job support had a significantly higher CVD risk score and lower well-being index than those reporting high job support. Furthermore, workers with high-stress tasks showed higher well-being index scores than those with passive tasks. Approximately 58% of the subjects were classified as low CVD risk (CVD risk <10%), approximately 31% were classified as moderate risk (CVD risk between 10 and 20%) and 11% were considered high risk (CVD risk >20%). The overall median CVD risk for the population was moderate (6.9%), with individual scores ranging from 1 to 58%. Discussion: Further analyses confirmed the protective effect of work support, also identifying physical inactivity, regular alcohol consumption and low educational level as factors contributing to an increased risk of CVD. Interestingly, factors such as job control and work support demonstrated a positive impact on psychological well-being. These results emphasise the importance of intervention strategies aimed at promoting health in the workplace. By addressing these combined factors, organisations can effectively reduce the risk of CVD and improve the general well-being of their workforce

Chandra View of the Dynamically Young Cluster of Galaxies A1367 I. Small-Scale Structures

The 40 ks \emph{Chandra} ACIS-S observation of A1367 provides new insights into small-scale structures and point sources in this dynamically young cluster. Here we concentrate on small-scale extended structures. A ridge-like structure around the center (``the ridge'') is significant in the \chandra\ image. The ridge, with a projected length of $\sim$ 8 arcmin (or 300 h$_{0.5}^{-1}$ kpc), is elongated from northwest (NW) to southeast (SE), as is the X-ray surface brightness distribution on much larger scales ($\sim$ 2 h$_{0.5}^{-1}$ Mpc). The ridge is cooler than its western and southern surroundings while the differences from its eastern and northern surroundings are small. We also searched for small-scale structures with sizes $\sim$ arcmin. Nine extended features, with sizes from $\sim$ 0.5$'$ to 1.5$'$, were detected at significance levels above 4 $\sigma$. Five of the nine features are located in the ridge and form local crests. The nine extended features can be divided into two types. Those associated with galaxies (NGC 3860B, NGC 3860 and UGC 6697) are significantly cooler than their surroundings (0.3 - 0.9 keV vs. 3 - 4.5 keV). The masses of their host galaxies are sufficient to bind the extended gas. These extended features are probably related to thermal halos or galactic superwinds of their host galaxies. The existence of these relatively cold halos imply that galaxy coronae can survive in cluster environment (e.g., Vikhlinin et al. 2001). Features of the second type are not apparently associated with galaxies. Their temperatures may not be significantly different from those of their surroundings. This class of extended features may be related to the ridge. We consider several possibilities for the ridge and the second type of extended features. The merging scenario is preferred.Comment: To appear in ApJ, Vol 576, 2002, Sep., a high-resolution version is in http://cfa160.harvard.edu/~sunm/a1367_a.ps.g

Bright ULXs from Ring Galaxies

Collisional Ring Galaxies (RiGs), with their expanding ring of gas and stars and their high star formation rate are unique objects where to study the most massive products of star formation and shed some light on the nature of ultra luminous X-ray sources (ULXs) found on their rings. We have recently constructed the X-ray luminosity function of ULXs in RiGs which is mostly consistent with previous results but shows two bright objects at the highest luminosity above the extrapolation of previous models for ULXs. They could be the best cases of Intermediate Mass Black Holes, or further ULXs powered by neutron stars, or even something different (e.g Supernovae). We will describe in detail the RiGs and their properties and compare the derived XLF with previous results

The Chandra survey of the COSMOS field II: source detection and photometry

The Chandra COSMOS Survey (C-COSMOS) is a large, 1.8 Ms, Chandra program, that covers the central contiguous ~0.92 deg^2 of the COSMOS field. C-COSMOS is the result of a complex tiling, with every position being observed in up to six overlapping pointings (four overlapping pointings in most of the central ~0.45 deg^2 area with the best exposure, and two overlapping pointings in most of the surrounding area, covering an additional ~0.47 deg^2). Therefore, the full exploitation of the C-COSMOS data requires a dedicated and accurate analysis focused on three main issues: 1) maximizing the sensitivity when the PSF changes strongly among different observations of the same source (from ~1 arcsec up to ~10 arcsec half power radius); 2) resolving close pairs; and 3) obtaining the best source localization and count rate. We present here our treatment of four key analysis items: source detection, localization, photometry, and survey sensitivity. Our final procedure consists of a two step procedure: (1) a wavelet detection algorithm, to find source candidates, (2) a maximum likelihood Point Spread Function fitting algorithm to evaluate the source count rates and the probability that each source candidate is a fluctuation of the background. We discuss the main characteristics of this procedure, that was the result of detailed comparisons between different detection algorithms and photometry tools, calibrated with extensive and dedicated simulations.Comment: Accepted for publication in The Astrophysical Journal Supplement Serie