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The present study investigates the mechanical properties of three types of Ti6Al4V ELI bone screws realized using the laser powder bed fusion (LPBF) process: a fully threaded screw and two groups containing differently arranged sectors made of lattice-based Voronoi (LBV) structure in a longitudinal and transversal position, respectively. This study aims to explore the potentialities related to the introduction of LBV structure and assess its impact on the implant’s primary stability and mechanical performance.

The optimized bone screw designs were realized using the LPBF process. The quality and integrity of the specimens were assessed by scanning electron microscopy and micro-computed tomography. Primary stability was experimentally verified by the insertion and removal of the screws in standard polyurethane foam blocks. Finally, torsional tests were carried out to compare and assess the mechanical strength of the different designs.

The introduction of the LBV structure decreases the elastic modulus of the implant. Longitudinal LBV type screws demonstrated the lowest insertion torque (associated with lower bone damage) while still displaying promising torsional strength and removal force compared with full-thread screws. The use of LBV structure can promote improved functional performances with respect to the reference thread, enabling the use of lattice structures in the biomedical sector.

The paper fulfils an identified interest in designing customized implants with improved primary stability and promising features for secondary stability.

The COVID-19 pandemic has induced tourism destinations to reconsider organisational aspects related to health safety measures, as perceptions of health safety may have become particularly important for tourists. Using data from summer 2020, the period immediately after the outbreak of the pandemic, we investigate the factors that affected tourist perceptions of health safety.

Data come from a survey of tourist-card holders in Trentino, an Italian mountain destination. Through regressions, we assess the conditional correlation between health safety measure evaluations following a holiday and a set of covariates related to the features of the tourist area and the tourists themselves, as well as COVID-19 incidence in their province of residence in the months before the holiday.

Tourist-related features seem not to impact on perceived health safety, whereas some destination- and accommodation-related elements do. In particular, the number of tourist beds affects it negatively, and staying at a hotel does it in a positive way. COVID-19 incidence in one’s home province does not affect perceptions of health safety measures, which suggests a possible sample selection effect and/or the need for more fine-grained data.

This paper is one of the few on the immediate effects of the COVID-19 pandemic using data from a large sample of actual tourists. Our findings point out the importance of the intrinsic features of some places and accommodation in influencing perceptions of safety. We discuss implications for scholars and destination managers.