Chemical composition and origin of nebulae around Luminous Blue Variables

We use the analysis of the heavy element abundances (C, N, O, S) in circumstellar nebulae around Luminous Blue Variables to infer the evolutionary phase in which the material has been ejected. (1) We discuss the different effects that may have changed the gas composition of the nebula since it was ejected (2) We calculate the expected abundance changes at the stellar surface due to envelope convection in the red supergiant phase. If the observed LBV nebulae are ejected during the RSG phase, the abundances of the LBV nebulae require a significantly smaller amount of mass to be lost than assumed in evolutionary models. (3) We calculate the changes in the surface composition during the main sequence phase by rotation induced mixing. If the nebulae are ejected at the end of the MS-phase, the abundances in LBV nebulae are compatible with mixing times between 5 x 10^6 and 1 x 10^7 years. The existence of ON stars supports this scenario. (4) The predicted He/H ratio in the nebulae are significantly smaller than the current observed photospheric values of their central stars. Combining various arguments we show that the LBV nebulae are ejected during the blue SG phase and that the stars have not gone through a RSG phase. The chemical enhancements are due to rotation induced mixing, and the ejection is possibly triggered by near-critical rotation. During the ejection, the outflow was optically thick, which resulted in a large effective radius and a low effective temperature. This also explains the observed properties of LBV dust.Comment: 18 pages, 4 figures, to be published in The Astrophysical Journal, April 20, 200

Stories of courage in a group of adults with Substance Use Disorder

The treatment for drug addiction is considered a difficult path for the most of patients. As matter of fact, individuals with Substance Use Disorder (SUD) experience numerous challenges before, during and after the treatment (e.g. tackling an unpredictable, uncertain and paradoxically negative future, tackling the anxiety and anticipatory fear of physical pain associated with abstinence; decide to go beyond self-justification and self-deception). Courage could be considered a positive and functional resource to help people with SUD to face challenges and difficulties related to treatment. In connection therewith, the aim of this study was to examine, using an embedded mix method analysis, the personal stories of courage of 80 individuals with SUD in order to identify the themes and types of courage used in their life. The analysis carried out showed that individuals with SUD reported more frequently stories of courage related to their SUD condition respect to other life situation. Moreover, the quantitative analysis showed that participants used more frequently psychological courage respect to moral and physical courage when these stories were referred to their SUD condition then other life situations

NGC 602 Environment, Kinematics and Origins

The young star cluster NGC 602 and its associated HII region, N90, formed in a relatively isolated and diffuse environment in the Wing of the Small Magellanic Cloud. Its isolation from other regions of massive star formation and the relatively simple surrounding HI shell structure allows us to constrain the processes that may have led to its formation and to study conditions leading to massive star formation. We use images from Hubble Space Telescope and high resolution echelle spectrographic data from the Anglo-Australian Telescope along with 21-cm neutral hydrogen (HI) spectrum survey data and the shell catalogue derived from it to establish a likely evolutionary scenario leading to the formation of NGC 602. We identify a distinct HI cloud component that is likely the progenitor cloud of the cluster and HII region which probably formed in blister fashion from the cloud's periphery. We also find that the past interaction of HI shells can explain the current location and radial velocity of the nebula. The surrounding Interstellar Medium is diffuse and dust-poor as demonstrated by a low visual optical depth throughout the nebula and an average HI density of the progenitor cloud estimated at 1 cm^-3. These conditions suggest that the NGC 602 star formation event was produced by compression and turbulence associated with HI shell interactions. It therefore represents a single star forming event in a low gas density region.Comment: Accepted for publication in PASP. 25 pages, 10 figure

The dusty Nebula surrounding HR Car: a Spitzer view

We present mid-IR observations of the Galactic Luminous Blue Variable (LBV) HR Car and its associated nebula carried out with the Spitzer Space Telescope using both IRAC and IRS, as part of a GTO program aimed to study stellar ejecta from evolved stars. Our observations reveal a rich mid-IR spectrum of the inner nebula showing both solid state and atomic gas signatures. Strong low-excitation atomic fine structure lines such as $26.0 \mu$m [\ion{Fe}{2}] and $34.8 \mu$m [\ion{Si}{2}], indicate, for the first time, the presence of a PDR in this object class. While the physics and chemistry of the low-excitation gas appears to be dominated by photodissociation, a possible contribution due to shocks can be inferred from the evidence of gas phase Fe abundance enhancement. The presence of amorphous silicates, inferred from the observed characteristic broad feature at $10 \mu$m located in the inner nebula, suggests that dust has formed during the LBV outburst. This is in contrast with the detection of crystalline dust in other probably more evolved Galactic LBVs, which is similar to the crystalline dust observed in red supergiants. This has been considered to be evidence of dust production during evolutionary phases prior to the outburst.Comment: 27 pages, 6 figures. accepted by Ap

Validation of the Childhood Career Development Scale Among Italian Middle School Students

During early adolescence, individuals engage in exploring educational opportunities, beginning to develop a career identity, contemplate future careers, and make tentative career decisions. Choices made during this period may have a strong effect on one\u2019s academic and career future, and in many countries, young adolescents must make important and sometimes final academic and career choices that impact the rest of their lives. Despite this, research on early adolescence is severely lacking. To address this gap, a validation study of the Childhood Career Development Scale (CCDS) was conducted with a young adolescent Italian sample. Consistent with previous research with younger samples, support was found for an eight-factor structure of the CCDS. Convergent validity was supported by positive associations with exploration, students\u2019 ideas, attitudes, and behaviors regarding their academic and career future and career self-efficacy. These findings support Super\u2019s dimensional model of childhood career development through early adolescence as originally theorized