Neutrino Mass Matrices with Vanishing Determinant and θ13\theta_{13}

We investigate the prospects for scenarios with vanishing determinant neutrino mass matrices and vanishing $\theta_{13}$ mixing angle. Normal and inverse mass hierarchies are considered separately. For normal hierarchy it is found that neutrinoless double beta decay cannot be observed by any of the present or next generation experiments. For inverse hierarchy the neutrinoless double beta decay is, on the contrary, accessible to experiments. We also analyse for both hierarchies the case for texture zeros and equalities between mass matrix elements. No texture zeros are found to be possible nor any such equalities, apart from the obvious ones.Comment: 14 pages, 1 figur

A model for fermion masses and lepton mixing in SO(10) x A4

The discrete flavor symmetry A4 explains very well neutrino data at low energy, but it seems difficult to extend it to grand unified models since in general left-handed and right-handed fields belong to different A4 representations. Recently it has been proposed a model where all the fermions equally transform under A4. We study here a concrete SO(10) realization of such a model providing small neutrino masses through the seesaw mechanism. We fit at tree level the charged fermion masses run up to the unification scale. Some fermion masses properties come from the SO(10) symmetry while lepton mixing angles are consequence of the A4 properties. Moreover, our model predicts the absolute value of the neutrino masses, these ones are in the range $m_\nu\simeq 0.005-0.052 eV$.Comment: 15 pages. V2: Final version to appear in the journa

Remaining inconsistencies with solar neutrinos: can spin flavour precession provide a clue?

A few inconsistencies remain after it has been ascertained that LMA is the dominant solution to the solar neutrino problem: why is the SuperKamiokande spectrum flat and why is the Chlorine rate prediction over two standard deviations above the data. There also remains the ananswered and important question of whether the active neutrino flux is constant or time varying. We propose a scenario involving spin flavour precession to sterile neutrinos with three active flavours that predicts a flat SuperK spectrum and a Chlorine rate prediction more consistent with data. We also argue that running the Borexino experiment during the next few years may provide a very important clue as to the possible variability of the solar neutrino flux.Comment: 3 pages, 2 figures, contribution to TAUP 2009 (Rome

Sexism, homophobia and transphobia in a sample of Italian pre-service teachers: the role of socio-demographic features

Although recent research has highlighted that lesbian, gay, bisexual and transgender (LGBT) youths represent a resilient population, they still suffer from social stigma and oppression, being potentially at additional risk of developing negative mental health outcomes. One of the main environments where violence and harassment against this population are present is the school. Within school contexts, the impact that teachers can have on the educational experiences of LGBT youths seems to be a crucial point. This paper explored sexist, homophobic and transphobic attitudes among 438 pre-service teachers in relation to specific socio-demographic features. Results indicated that being male, heterosexual, conservative and currently religious were positively associated with sexist, homophobic, and transphobic attitudes and feelings, and having a LGBT friend was negatively associated with homophobic and transphobic attitudes and feelings. These results suggest the need to introduce specific training on the deconstruction of gender and sexual stereotypes and prejudices, to provide teachers with efficient tools to address diversity in the classrooms and to implement inclusive school policies. Suggestions for the implementation of good practices are provided

Identity complexity and integration in lesbian, gay, bisexual and heterosexual adolescents and emerging adults: Implications for clinical practice

The present study aimed at assessing whether differences exist in identity complexity and integration between 31 lesbian, gay, and bisexual (LGB) and 33 heterosexual youths (mean age 21.47, SD = 3.27), both Italian and US. Participants completed a newly created questionnaire, the Identity Labels and Life Contexts Questionnaire (ILLCQ), which assesses the interplay between identity dimensions and life contexts. The ILLCQ assesses identity integration on three levels: (a) integration among the different domains of identity in their intersection with the various life contexts (assessed through salience and centrality); (b) integration between an individual’s self-definition and the definition of self made by others (perceived self-recognition); and (c) the integration between how the person perceives her/himself to be and the way she/he shows her/himself to others. Results suggest that identity salience varies significantly across life contexts for both LGB and heterosexual youths. The only significant difference between the LGB and heterosexual groups was higher salience and centrality of the sexual orientation domain for LGB youths. Sexuality represents a core identity domain for LGB participants, and perhaps less so for heterosexual participants. LGB youths reported lower general identity recognition from other people. Implications for clinical practice are discussed