A fully Eulerian multiphase model of windblown sand coupled with morphodynamic evolution: Erosion, transport, deposition, and avalanching

Abstract Modeling unsteady windblown sand dynamics requires not only treatment of the sand present in the air as a suspended constituent of a mixture but also consideration of erosion and sedimentation phenomena and consequently of the morphodynamic evolution of the sand-bed surface, including avalanching, especially in the presence of natural or human-built obstacles, artifacts, and infrastructures. With this aim in mind, we present a comprehensive multiphase model capable of accurately simulating all the physical phenomena mentioned above, producing satisfactory results, with reasonable computational effort. As test cases, two- and three-dimensional simulations of dune evolution are reported, as is windblown sand transport over a straight vertical wall. Examples of sand transport around other obstacles are given to show the flexibility of the model and its usefulness for such engineering applications

Semistable Higgs bundles on Calabi-Yau manifolds

We provide a partial classification of semistable Higgs bundles over a simply connected Calabi-Yau manifolds. Applications to a conjecture about a special class of semistable Higgs bundles are given. In particular, the conjecture is proved for K3 and Enriques surfaces, and some related classes of surfaces

COVID-19 and the impact on the cranio-oro-facial trauma care in Italy: An epidemiological retrospective cohort study

The coronavirus disease 2019 (COVID-19) has deeply modified the organization of hospitals, health care centers, and the patient’s behavior. The aim of this epidemiological retrospective cohort study is to evaluate if and how the COVID-19 pandemic has determined a modification in cranio-oro-facial traumatology service. Methods: The dataset included hospital emergency room access of a six-month pre-pandemic period and six months into pandemic outbreak. The variables collected were: patient age, gender, type of emergency access with relative color code, Glasgow Coma Scale Score, type of discharge. Results: 537 vs 237 (pre-pandemic vs pandemic) patients accessed the hospital emergency room and the mean age decreased from 60.79 ± 25.34 to 56.75 ± 24.50 year. Yellow and green code access went from 28.9% and 66.1% to 37.5% and 57.7% (pre-pandemic vs pandemic). Glasgow Coma Scale (GCS) shows an increase of 16.6% vs 27.8% of 15 grade score, a 28.7% vs 28.5% of the 14 grade score and reduction of 13 and 12 grade 40.2% and 14.5% vs 37.1 and 9.7% (pre-pandemic vs pandemic). Conclusions: Since the COVID-19 outbreak continues, epidemiological data are still necessary to perform public health intervention strategies and to appropriately predict the population needs, in order to properly manage the COVID-19 related to oral pathologies as well as the most common health problems

Life Cycle Inventory (LCI) analysis of the Sicilian artistic and traditional ceramics as a tool for sustainable manufacturing

In the last few decades, greater attention is being paid by the Italian industrial ceramics sector to the environmental impacts related to ceramics production cycle and many companies have acquired voluntary environmental certifications (ISO 14001 or EMAS) or labeling (Ecolabel or EPD). This is not the case with the artistic ceramics sector in which few companies are certified. One of the most common and used tool for evaluating the environmental impact of products is the Life Cycle Assessment (LCA) methodology. This paper presents the preliminary results from a Life Cycle Inventory (LCI) analysis of the artistic ceramics sector in Caltagirone (Italy). Representative life cycle inventories are essential for any good quality LCA. They represent the fundamental blocks for compiling the full LCA of the ceramics production process, hence promoting environmental sustainability

Modeling sand slides by a mechanics-based degenerate parabolic equation

Avalanching plays a crucial role in granular materials dynamics, in particular in the evolution of the shape of the leeward side of sand dunes. This paper presents a physically-based mathematical model capable of reproducing the kinematic evolution of the surface of sand piles and to obtain eventually the stationary configurations, in the presence of external sources as well. Simulation results with different boundary conditions and geometries are reported in order to show the high flexibility of the model. The model is also validated by means of comparison with the experimental results of different authors