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Le nuove disposizioni in materia di sicurezza pubblica e di prevenzione del terrorismo
No full textIl tema della sicurezza delle città è relativamente nuovo nel panorama legislativo nazionale, anche se le progettualità ideate per migliorare le
condizioni di sicurezza – oggettiva e percepita – dei cittadini e sviluppare un sistema integrato di interventi, intrecciando il rafforzamento
dell’attività di controllo con l’attività di prevenzione, risalgono agli anni ’90 del XX secolo (ci si riferisce, in particolare, al “Progetto città
sicure”, avviato in Emilia Romagna nel 1994 da studiosi e accademici), anche in ragione dell’urbanesimo che aveva fatto seguito al boom
economico degli anni ‘60.
Bisogna attendere il varo dei primi “pacchetti sicurezza” del XXI secolo ed in particolare la riforma del 2008 per assistere a due rilevanti
innovazioni:
in primo luogo, viene previsto in capo al sindaco, accanto al tradizionale potere di adozione di ordinanze contingibili e urgenti, un ulteriore
potere di ordinanza, svincolato dai presupposti di natura emergenziale;
in secondo luogo, viene introdotto, sempre nell’ambito dell’esercizio del potere di ordinanza, il concetto di “sicurezza urbana”, che si affianca a
quello di “incolumità pubblica” (prima “incolumità dei cittadini”
Development of an innervated human skin equivalent to model nociceptive circuitry in vitro
No full textThe reconstruction of innervated skin equivalents in vitro to recapitulate the somatosensory system is central to advancing our understanding of nociceptive circuitry and holds significant potential for various industrial applications. As skin–nerve crosstalk is increasingly recognized as a key element in skin physiology and nociception, the development of reliable in vitro models to evaluate the functional activity of neuroepithelial junctions is highly warranted. However, existing models often fall short in replicating the full complexity of interactions among sensory neurons, keratinocytes, fibroblasts, Schwann cells, and the extracellular matrix (ECM). In this study, we have developed an Innervated Human Skin Equivalent (IHSE), composed of a fibroblast-populated endogenous ECM enriched with human Schwann cells and topped with a fully differentiated epithelium that recapitulates basal, germinative, and keratinized layers. The IHSE was innervated using axonal projections from rat dorsal root ganglion (R-DRG) sensory neurons cultured on a high-density microelectrode array (HD-MEA). Axons emerging from the neuronal layer progressively extended through the dermal compartment and established connections with the epidermal layer, ultimately forming a well-structured neuroepithelial junction. Real-time electrophysiological recordings from the HD-MEA showed that both neuronal firing rates and the number of active microelectrodes increased as innervation progressed. By day 9, a fully developed neural network was established, featuring both free nerve endings-like structures and mature neuroepithelial junctions. Functional validation was performed by applying a drop of capsaicin solution to the apical side of the epidermis. This induced a distinct spatial and temporal electrical response as captured by the MEA, indicating activation of nociceptive terminals at the neuroepithelial junction. The electrical signal propagated to the DRG neurons on the MEA, effectively replicating the in vivo nociceptive transmission pathway. This model provides a relevant physiological platform for studying acute and chronic pain mechanisms and offers a valuable tool for the development of novel pain therapeutics
Reframing Circularity. Modelli di intervento integrati per la rigenerazione della costa metropolitana di Napoli
No full textClimate policies, energy shocks and spillovers between green and brown stock price indices
No full textThis paper examines the effects of climate policies and energy shocks on mean and volatility spillovers between green and brown stock price indices in five countries (Canada, India, Japan, the UK and the US). More specifically, bivariate GARCH-BEKK models including dummy variables controlling for these shocks are estimated using weekly series with start dates ranging from March 13, 2009 to August 24, 2012 (depending on data availability for the green index) and an end date of December 29, 2023. Significant dynamic linkages between green and brown indices are found when climate policy and oil shocks are considered jointly. Some common patterns emerge, such as shifts in spillover dynamics between green and brown assets, but also country-specific effects of the climate policy shocks which reflect differences in regulatory frameworks and policies. By contrast, energy shocks tend to have a more uniform impact. Further, the interaction between climate policy and energy shocks weakens cross-market linkages, enhancing portfolio diversification opportunities for green investors. The conditional correlation analysis confirms this finding, suggesting that green stocks can be used as an effective hedge. These results highlight the benefits of incorporating green assets into diversified portfolios, particularly in financial centers where, in recent years, they have offered higher returns and lower volatility
Pre-processing history dependent foaming behavior and morphing of thermoplastic polyurethane
No full textThermoplastic polyurethanes (TPUs) foams are valued for their low density, energy absorption, low thermal con
ductivity, and, in general, tunable properties. These features make them ideal for applications such as sportswear,
flexible electronics, shape memory sensors, and soft robotics. Foaming of thermoplastic polymers is highly af
fected by the state of the polymer in terms of molecular chain arrangement, crystallinity, and residual stresses,
which, in turn, are strongly influenced by the pre-processing history of the material. These complexities, together
with multiphase morphology, make TPU foaming particularly challenging for achieving high expansion ratios.
Preforms with different thermal and deformation histories are here selected to serve as models for exploring the
relationship between pre-processing and foaming, with and without the addition of fillers. We analyze the ex
pansion ratio, foam morphology, microstructural features, and post-foaming shrinkage of neat TPU, 3D-printed
TPU structures, and TPU composites with multi-walled carbon nanotubes and aluminum nanoparticles using the
batch foaming technique under varying processing conditions. Results show the critical role of pre-processing (in
terms of printing parameters) and addition of fillers in influencing the foamability, and highlight microstructural
control through pre-processing as a key strategy to tailor TPU foams for advanced structural and functional ap
plications. Building on this, we introduce foam-induced morphing, validating mold-free batch foaming as a tool
for designing lightweight systems with precisely tuned mechanics and morphing behavior
Investigating the uniaxial compressive mechanics of graded polymer foams via in-situ synchrotron X-ray microtomography
No full textGraded polymer foams are emerging as transformative materials for structural applications, outperforming uniform foams due to their spatially tailored density and microstructural features. However, harnessing their full potential requires a deep understanding of how their macroscopic mechanical behavior relates to their complex microstructure evolution. In this study, we elucidate the uniaxial compressive response of graded foams using in-situ synchrotron X-ray microtomography, complemented by comparative experiments on uniform foams of varying densities. Our findings reveal that graded foams exhibit both qualitatively and quantitatively distinct mechanical behavior, driven by unique microscale deformation mechanisms. We evaluate and discuss their superior energy absorption performance and demonstrate how the density, cell size and circularity profile evolves under increasing macroscopic strain. Notably, the graded architecture enables precise control over the localization and progression of densification bands, offering unprecedented design flexibility for advanced structural applications
A summary of the Lucy Ashton resistance prediction workshop
No full textA blind full-scale CFD resistance prediction workshop was held in 2024, with the Lucy Ashton paddle steameras its test case. Results from forty participants were received for the three different parts in which the workshopwas organised, which consisted of a grid refinement study with common grids, full-scale simulations for varyingFroude number, and model-scale simulations at a constant Froude number for varying model sizes. This paperpresents a summary of the results gathered for the workshop along with its main findings, and the comparisonwith the results available from the experimental campaign carried out for the Lucy Ashton in the 1950s. Thecomputational results led to lower ship resistance than the experimental data for all conditions, due to the simulations considering the ship to be hydrodynamically smooth and to not heave or pitch. The scatter of the resistanceat full-scale showed a decreasing trend as the Froude number was increased with a median absolute deviation ofat most 2.3 %. The spread in the numerical results obtained for the full-scale conditions was equivalent to thatobserved for the model-scale cases, building further confidence in full-scale CFD
Optimal convergence of IgA collocation methods
No full textIsogeometric collocation discretizes the strong form of a PDE on smooth spline spaces and therefore avoids element integration, but its spatial accuracy is highly sensitive to the placement of the collocation nodes. For this reason methods are tested on linear elliptic problems in order to verify convergence properties. Classical choices such as Greville abscissae may yield suboptimal convergence in both H1 and L2 norms for several spline degrees and problem settings. Node sets derived from (estimated) superconvergent (Cauchy–Galerkin) points – e.g. alternating subsets, clustered variants, or least–squares sets – frequently improve the observed L2 behaviour and in favourable cases approach the Galerkin benchmark, though this is not universal across all degrees, boundary conditions, and PDE types. In this paper we find for the first choices of points that recover optimal convergence for polynomial degrees p=4,6,8. The construction is made in order to recover the symmetry inside every knot span also for even degrees, as done in the above mentioned methods. Although the exact reason for this behaviour could not be clearly identified, the numerical evidence suggests that restoring local symmetry recovers the optimal rate. Unfortunately, as most of the previously proposed methods, this results in a collocation system with more equations than degrees of freedom number of degrees of freedom, thus the overall system is solved in a least–square sense
Analytical estimation model for direct seismic economic losses based on extension and distribution of damage
No full textExisting models for estimating expected losses due to future earthquakes are mainly based on empirical, site-specific data collected after real earthquakes, and generally refer to the maximum damage level observed in buildings. However, the expected direct economic losses also depend on the extension and distribution of damage along the building height. In this paper, a methodology for deriving analytical functions to estimate direct economic losses by explicitly accounting for both the severity and distribution of damage along the building height has been developed and applied to some RC building types widespread in Italy and Southern Europe