A rigorous implementation of the Jeans--Landau--Teller approximation

Rigorous bounds on the rate of energy exchanges between vibrational and translational degrees of freedom are established in simple classical models of diatomic molecules. The results are in agreement with an elementary approximation introduced by Landau and Teller. The method is perturbative theory ``beyond all orders'', with diagrammatic techniques (tree expansions) to organize and manipulate terms, and look for compensations, like in recent studies on KAM theorem homoclinic splitting.Comment: 23 pages, postscrip

Numerical investigation on load transfer effects in bogies of urban rail vehicles

Urban rail vehicles can present many types of architecture, definitely different from those of traditional rail vehicles. When dealing with long articulated tramcars, complex coupling effects between the vertical and lateral dynamics may arise. Making reference to a modern tramcar, the coupling phenomena are investigated in detail by means of numerical simulation, considering the dynamic behaviour during the negotiation of curves with or without superelevation

Italian validation of the “vocal test about mental states” (TVSM), a new advanced theory of mind task for school age children

Recently researches on Theory of Mind (the ability to impute mental states to the self and to the others as cause of behaviors) are focused on the understanding of complex mental states, both epistemic and emotional states, that develops after the age of four, when children reach the comprehension of the false belief. There are few Theory of Mind tasks that specifically assess this ability, that become more and more sophisticated during the development. In particular, these tasks require to understand mental states from narrative (short stories) or visual stimuli (eyes or faces expressions). Adopting a wide definition of Theory of Mind, conceptualized as a multicomponential ability, we propose a new instrument, the “Vocal Test about Mental States” (TVSM), that assesses the understanding of a wide range of complex epistemic and emotional mental states from non verbal vocal cues. In this work we describe the test construction, validation (on a sample of 220 children) and reliability (Cronbach's alpha, on a sample of 170 children, and test-retest, on a sample of 141 children). The test showed good psychometric properties: it is a valid advanced Theory of Mind task. Moreover, we found that the performance in the TVSM is predicted by the verbal ability (assessed with the PPVT-R) and not by the nonverbal IQ (Raven's matrices)