Studio dell'inquinamento acustico da traffico ferroviario mediante modelli di simulazione: applicazione a casi reali

La tesi rappresenta un tentativo di replicare la misura del rumore ferroviario condotta da RFI. Si compone di una parte di effettiva misura del rumore tramite fonometro, di successiva analisi dei dati e di una parte finale di simulazione con successiva taratura del modelloope

Polysaccharide hydrogels for multiscale 3D printing of pullulan scaffolds

Structurally and mechanically similar to the extracellular matrix (ECM), biomimetic hydrogels offer a number of opportunities in medical applications. However, the generation of synthetic microenvironments that simulate the effects of natural tissue niches on cell growth and differentiation requires new methods to control hydrogel feature resolution, biofunctionalization and mechanical properties. Here we show how these goals can be achieved by using a pullulan-based hydrogel, engineered in composition and server as cell-adhesive hydrogel, 3D photo-printable in dimension, ranging from the macro- to the micro-scale dimensions, and of tunable mechanical properties. For this, we used absorbers that limit light penetration, achieving 3D patterning through stereolithography with feature vertical resolution of 200 μm and with overall dimension up to several millimeters. Furthermore, we report the fabrication of 3D pullulan-modified hydrogels by two-photon lithography, with sub-millimetric dimensions and minimum feature sizes down to some microns. These materials open the possibility to produce multiscale printed scaffolds that here we demonstrate to be inert for cell adhesion, but biologically compatible and easily functionalizable with cell adhesive proteins. Under these conditions, successful cell cultures were established in 2D and 3D. Keywords: Hydrogel, Biomaterials, Polysaccharide, Pullulan, 3D printing, Two photon laser lithography, Mesenchymal stromal cell

Quantitative assessment of common practice procedures in the fair evaluation of embedded options in insurance contracts

This work analyses the common industry practice used to evaluate financial options written on with-profit policies issued by European insurance companies. In the last years regulators introduced, with the Solvency II directive, a market consistent valuation framework for determining the fair value of asset and liabilities of insurance funds. A relevant aspect is how to deal with the estimation of sovereign credit and liquidity risk, that are important components in the valuation of the majority of insurance funds, which are usually heavily invested in treasury bonds. The common practice is the adoption of the certainty equivalent approach (CEQ) for the risk neutral evaluation of insurance liabilities, which results in a deterministic risk adjustment of the securities cash flows. In this paper, we propose an arbitrage free stochastic model for interest rate, credit and liquidity risks, that takes into account the dependences between different government bond issuers. We test the impact of the common practice against our proposed model, via Monte Carlo simulations. We conclude that in the estimation of options whose pay-off is determined by statutory accounting rules, which is often the case for European traditional with-profit insurance products, the deterministic adjustment for risk of the securities cash flows is not appropriate, and that a more complete model such as the one described in this article is a viable and sensible alternative in the context of market consistent evaluations

Stroke management during the coronavirus disease 2019 (COVID-19) pandemic: experience from three regions of the north east of Italy (Veneto, Friuli-Venezia-Giulia, Trentino-Alto-Adige)

Background: Efficiency of care chain response and hospital reactivity were and are challenged for stroke acute care management during the pandemic period of coronavirus disease 2019 (COVID-19) in North-Eastern Italy (Veneto, Friuli-Venezia-Giulia, Trentino-Alto-Adige), counting 7,193,880 inhabitants (ISTAT), with consequences in acute treatment for patients with ischemic stroke. Methods: We conducted a retrospective data collection of patients admitted to stroke units eventually treated with thrombolysis and thrombectomy, ranging from January to May 2020 from the beginning to the end of the main first pandemic period of COVID-19 in Italy. The primary endpoint was the number of patients arriving to these stroke units, and secondary endpoints were the number of thrombolysis and/or thrombectomy. Chi-square analysis was used on all patients; furthermore, patients were divided into two cohorts (pre-lockdown and lockdown periods) and the Kruskal-Wallis test was used to test differences on admission and reperfusive therapies. Results: In total, 2536 patients were included in 22 centers. There was a significant decrease of admissions in April compared to January. Furthermore, we observed a significant decrease of thrombectomy during the lockdown period, while thrombolysis rate was unaffected in the same interval across all centers. Conclusions: Our study confirmed a decrease in admission rate of stroke patients in a large area of northern Italy during the lockdown period, especially during the first dramatic phase. Overall, there was no decrease in thrombolysis rate, confirming an effect of emergency care system for stroke patients. Instead, the significant decrease in thrombectomy rate during lockdown addresses some considerations of local and regional stroke networks during COVID-19 pandemic evolution

In silico toxicology protocols

The present publication surveys several applications of in silico (i.e., computational) toxicology approaches across different industries and institutions. It highlights the need to develop standardized protocols when conducting toxicity-related predictions. This contribution articulates the information needed for protocols to support in silico predictions for major toxicological endpoints of concern (e.g., genetic toxicity, carcinogenicity, acute toxicity, reproductive toxicity, developmental toxicity) across several industries and regulatory bodies. Such novel in silico toxicology (IST) protocols, when fully developed and implemented, will ensure in silico toxicological assessments are performed and evaluated in a consistent, reproducible, and well-documented manner across industries and regulatory bodies to support wider uptake and acceptance of the approaches. The development of IST protocols is an initiative developed through a collaboration among an international consortium to reflect the state-of-the-art in in silico toxicology for hazard identification and characterization. A general outline for describing the development of such protocols is included and it is based on in silico predictions and/or available experimental data for a defined series of relevant toxicological effects or mechanisms. The publication presents a novel approach for determining the reliability of in silico predictions alongside experimental data. In addition, we discuss how to determine the level of confidence in the assessment based on the relevance and reliability of the information

Studio dell'inquinamento acustico da traffico ferroviario mediante modelli di simulazione: applicazione a casi reali

La tesi rappresenta un tentativo di replicare la misura del rumore ferroviario condotta da RFI. Si compone di una parte di effettiva misura del rumore tramite fonometro, di successiva analisi dei dati e di una parte finale di simulazione con successiva taratura del modell