Many-body models for molecular nanomagnets

We present a flexible and effective ab-initio scheme to build many-body models for molecular nanomagnets, and to calculate magnetic exchange couplings and zero-field splittings. It is based on using localized Foster-Boys orbitals as one-electron basis. We apply this scheme to three paradigmatic systems, the antiferromagnetic rings Cr8 and Cr7Ni and the single molecule magnet Fe4. In all cases we identify the essential magnetic interactions and find excellent agreement with experiments.Comment: 5 pages, 3 figure

Optimized Confinement of Fermions in Two Dimensions

One of the challenging features of studying model Hamiltonians with cold atoms in optical lattices is the presence of spatial inhomogeneities induced by the confining potential, which results in the coexistence of different phases. This paper presents Quantum Monte Carlo results comparing meth- ods for confining fermions in two dimensions, including conventional diagonal confinement (DC), a recently proposed 'off-diagonal confinement' (ODC), as well as a trap which produces uniform den- sity in the lattice. At constant entropy and for currently accessible temperatures, we show that the current DC method results in the strongest magnetic signature, primarily because of its judicious use of entropy sinks at the lattice edge. For d-wave pairing, we show that a constant density trap has the more robust signal and that ODC can implement a constant density profile. This feature is important to any prospective search for superconductivity in optical lattices

Quantum Monte Carlo estimators for the positron-electron annihilation rate in bound and low-energy scattering states

Variational and exact estimators for the positron-electron annihilation rate in bound states of systems containing a positron in the framework of quantum Monte Carlo methods are presented. The modification needed to compute the effective number of electrons Z(eff) when scattering states are concerned is also discussed. The algorithms are tested against four cases for which close to exact results are available, finding an overall good agreement. The systems are Ps(-), PsH, and the s-wave scattering component of e(+)H and e(+)He

The Storm Doesn’t Touch me!—The Role of Perceived Employability of Students and Graduates in the Pandemic Era

Perceived Employability acquires growing relevance as a psychological protective resource now that new entrants in the labour market from higher education are experiencing a deterioration of their occupational prospects due to the COVID-19 pandemic, which brings worries and jeopardises psychological well-being. This study aims to extend research on perceived employability among Italian University students and graduates. Perceived employability is posited to predict flourishing directly and indirectly by reducing material, social, and health worries related to COVID-19. Moreover, this study contends that perceived employability buffers the positive impact of perceived adverse conditions of the labour market on worries, changing the effect on flourishing. In total, 471 university students and graduates completed an online survey. The analyses reveal that perceived employability positively influences flourishing directly and indirectly by reducing COVID-19-related worries. Nevertheless, the results do not support the moderating action of perceived employability. Despite some limitations (e.g., a cross-sectional design), this study significantly advances the exploration of perceived employability as a critical personal resource to deal with the transition to work under pandemic-related crises. This study draws on its results to advise higher education to increase perceived employability, such as through career guidance activities and work-based learning experiences

A Low-Cost Monitoring Platform and Visual Interface to Analyse Thermal Comfort in Smart Building Applications Using a Citizen–Scientist Strategy

Smart building issues are critical for current energy and comfort managing aspects in built environments. Nevertheless, the diffusion of smart monitoring solutions via user-friendly graphical interfaces is still an ongoing issue subject to the need to diffuse a smart building culture and a low-cost series of solutions. This paper proposes a new low-cost IoT sensor network, exploiting Raspberry Pi and Arduino platforms, for collecting real-time data and evaluating specific thermal comfort indicators (PMV and PPD). The overall architecture was accordingly designed, including the hardware setup, the back-end and the Android user interface. Eventually, three distinct prototyping platforms were deployed for initial testing of the general system, and we analysed the obtained results for different building typologies and seasonal periods, based on collected data and users’ preferences. This work is part of a large educational and citizen science activity