Follow-up observations of X-ray emitting hot subdwarf star: the He-rich sdO BD +37{\deg} 1977

We report on the results of the first XMM-Newton satellite observation of the luminous and helium-rich O-type subdwarf BD +37{\deg} 1977 carried out in April 2014. X-ray emission is detected with a flux of about 4*10^(-14) erg/cm2/s (0.2-1.5 keV), corresponding to a f_X/f_bol ratio about 10^(-7); the source spectrum is very soft, and is well fit by the sum of two plasma components at different temperatures. Both characteristics are in agreement with what is observed in the main-sequence early-type stars, where the observed X-ray emission is due to turbulence and shocks in the stellar wind. A smaller but still significant stellar wind has been observed also in BD +37{\deg} 1977; therefore, we suggest that also in this case the detected X-ray flux has the same origin.Comment: 6 pages. Accepted for publication by Astronomy and Astrophysic

Effect of morphology and defectiveness of graphene-related materials on the electrical and thermal conductivity of their polymer nanocomposites

In this work, electrically and thermally conductive poly (butylene terephthalate) nanocomposites were prepared by in-situ ring-opening polymerization of cyclic butylene terephthalate (CBT) in presence of a tin-based catalyst. One type of graphite nanoplatelets (GNP) and two different grades of reduced graphene oxide (rGO) were used. Furthermore, high temperature annealing treatment under vacuum at 1700{\deg}C was carried out on both RGO to reduce their defectiveness and study the correlation between the electrical/thermal properties of the nanocomposites and the nanoflakes structure/defectiveness. The morphology and quality of the nanomaterials were investigated by means of electron microscopy, x-ray photoelectron spectroscopy, thermogravimetry and Raman spectroscopy. Thermal, mechanical and electrical properties of the nanocomposites were investigated by means of rheology, dynamic mechanical thermal analysis, volumetric resistivity and thermal conductivity measurements. Physical properties of nanocomposites were correlated with the structure and defectiveness of nanoflakes, evidencing a strong dependence of properties on nanoflakes structure and defectiveness. In particular, a significant enhancement of both thermal and electrical conductivities was demonstrated upon the reduction of nanoflakes defectiveness

Effect of processing conditions on the thermal and electrical conductivity of poly (butylene terephthalate) nanocomposites prepared via ring-opening polymerization

Successful preparation of polymer nanocomposites, exploiting graphene-related materials, via melt mixing technology requires precise design, optimization and control of processing. In the present work, the effect of different processing parameters during the preparation of poly (butylene terephthalate) nanocomposites, through ring-opening polymerization of cyclic butylene terephthalate in presence of graphite nanoplatelets (GNP), was thoroughly addressed. Processing temperature (240{\deg}C or 260{\deg}C), extrusion time (5 or 10 minutes) and shear rate (50 or 100 rpm) were varied by means of a full factorial design of experiment approach, leading to the preparation of polybutylene terephthalate/GNP nanocomposite in 8 different processing conditions. Morphology and quality of GNP were investigated by means of electron microscopy, X-ray photoelectron spectroscopy, thermogravimetry and Raman spectroscopy. Molecular weight of the polymer matrix in nanocomposites and nanoflake dispersion were experimentally determined as a function of the different processing conditions. The effect of transformation parameters on electrical and thermal properties was studied by means of electrical and thermal conductivity measurement. Heat and charge transport performance evidenced a clear correlation with the dispersion and fragmentation of the GNP nanoflakes; in particular, gentle processing conditions (low shear rate, short mixing time) turned out to be the most favourable condition to obtain high conductivity values

Perfectionism or Perfectionisms in Orthorexia Nervosa

Purpose: Perfectionism is considered a transdiagnostic construct that characterises eating disorders (EDs) and obsessive-compulsive disorder (OCD) and that could also depict orthorexia nervosa (ON). The principal aim of this study was to investigate what dimensions of perfectionism mostly represent ON. Moreover, it was evaluated if dieting impacted the presence of orthorexic features and perfectionistic behaviour. Methods: The sample consisted of two groups-the "Diet" (n = 93), and the "No Diet" (n = 94) groups-composed of people with high and low orthorexic tendencies, respectively. Participants filled out self-report questionnaires to investigate orthorexic tendencies and different facets of perfectionism. Results: Analyses highlighted that people with high orthorexic tendencies showed higher perfectionistic features and that ON had a significant relationship with different facets of perfectionism. No interactions with diet were found. Therefore, no other differences were highlighted when the group type (Diet/No Diet) was considered. Conclusions: Regardless of diet, different facets of perfectionism characterise ON: perfectionism as a personality trait and perfectionism related to EDs and to obsessive-compulsive features. Our results evidenced that perfectionism could also be considered a useful construct in the conceptualization of orthorexia nervosa

New trends in teacher\u2019s education. Educational placement of the adopted child

In Italy, the number of adopted school-age children is increasing. According to the Commission of Intercountry Adoption (2013), 3106 children were adopted, 47.5% of them are between 5 and 9 years old. The present action-research aims at exploring the spread of good approaches in schools in terms of welcoming of adopted children. For this purpose, 268 teachers of primary schools were involved in analyzing the social representation about adopted children and their family. The results show a simplified vision of the adoptive family, which is described as heroic family or, on the contrary, as a family with difficulty

Prognostic role of chromosome 9P deletion in patients with clear cell renal cell carcinoma

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