Space-weighted seismic attenuation mapping of the aseismic source of Campi Flegrei 1983-84 unrest

Peer reviewedPublisher PD

Prediction of extreme events in the OFC model on a small world network

We investigate the predictability of extreme events in a dissipative Olami-Feder-Christensen model on a small world topology. Due to the mechanism of self-organized criticality, it is impossible to predict the magnitude of the next event knowing previous ones, if the system has an infinite size. However, by exploiting the finite size effects, we show that probabilistic predictions of the occurrence of extreme events in the next time step are possible in a finite system. In particular, the finiteness of the system unavoidably leads to repulsive temporal correlations of extreme events. The predictability of those is higher for larger magnitudes and for larger complex network sizes. Finally, we show that our prediction analysis is also robust by remarkably reducing the accessible number of events used to construct the optimal predictor.Comment: 5 pages, 4 figure

Crack-Like Processes Governing the Onset of Frictional Slip

We perform real-time measurements of the net contact area between two blocks of like material at the onset of frictional slip. We show that the process of interface detachment, which immediately precedes the inception of frictional sliding, is governed by three different types of detachment fronts. These crack-like detachment fronts differ by both their propagation velocities and by the amount of net contact surface reduction caused by their passage. The most rapid fronts propagate at intersonic velocities but generate a negligible reduction in contact area across the interface. Sub-Rayleigh fronts are crack-like modes which propagate at velocities up to the Rayleigh wave speed, VR, and give rise to an approximate 10% reduction in net contact area. The most efficient contact area reduction (~20%) is precipitated by the passage of slow detachment fronts. These fronts propagate at anomalously slow velocities, which are over an order of magnitude lower than VR yet orders of magnitude higher than other characteristic velocity scales such as either slip or loading velocities. Slow fronts are generated, in conjunction with intersonic fronts, by the sudden arrest of sub-Rayleigh fronts. No overall sliding of the interface occurs until either of the slower two fronts traverses the entire interface, and motion at the leading edge of the interface is initiated. Slip at the trailing edge of the interface accompanies the motion of both the slow and sub-Rayleigh fronts. We might expect these modes to be important in both fault nucleation and earthquake dynamics.Comment: 19 page, 5 figures, to appear in International Journal of Fractur

Geophysical responses to an environmentally-boosted volcanic unrest

The spatiotemporal relationship between geophysical, environmental, and geochemical responses during volcanic unrest is essentially unknown, making their joint use and interpretation for eruption forecasting challenging. Here, Empirical Orthogonal Functions analysis applied to GPS data allows the separation of the dominant deep-sourced inflation from environmentally controlled signals associated with extension at Campi Flegrei caldera. This separation bridges the gap between deformation, seismic and geochemical responses, clarifying the processes underlying the ongoing volcanic unrest. Persistent meteoric forcing during the 2017–2018 hydrological year changed the decadal trend of seismic energy and secondary deformation components, pairing their spatial patterns. The result was a block in the carbon dioxide released in 2018 at Solfatara, the primary stress-release valve at the caldera. The subsequent overpressure weakened the fractured eastern caldera, opening pathways for deep, hot materials to reach the surface. Our results give insight into how environmental forcing can favor volcanic unrest in pressurized calderas

Non autosufficienza: analisi e proposte per un nuovo modello di tutela

L\u2019Unione europea ha recentemente ribadito, nell\u2019ambito dell\u2019iniziativa circa il Pilastro Europeo dei Diritti Sociali, l\u2019esigenza di rinnovamento dei sistemi di welfare per realizzare risposte efficaci a nuovi bisogni, a tal fine incoraggiando strategie di innovazione sociale. In Italia ci\uf2 \ue8 particolarmente vero con riferimento al problema della non autosufficienza: siamo uno dei Paesi pi\uf9 longevi al mondo, ma la qualit\ue0 della vita in termini di buona salute e/o limitazioni funzionali non \ue8 altrettanto confortante. La risposta sia pubblica che privata continua ad essere nettamente inadeguata sotto il profilo quali/quantitativo: frammentazione disorganizzata di interventi con conseguente rischio di inappropriatezza delle prestazioni, dispersione delle gi\ue0 scarse risorse e attribuzione alle famiglie dell\u2019onere organizzativo e in gran parte di quello economico dell\u2019assistenza. Lo studio intende definire i contorni di un possibile nuovo modello di copertura della non autosufficienza basato su una logica di welfare life-cycle che superi la rigida struttura a silos che caratterizza il vigente sistema di welfare, fornendo indicazioni circa la sua concreta fattibilit\ue0, in particolare individuando le diverse componenti del modello; possibili attori e relative relazioni; i costi e le relative coperture; i necessari interventi legislativi. L\u2019analisi sar\ue0 condotta nel rispetto dei seguenti principi: a) approccio multidimensionale integrato, che realizzi sinergie fra servizi sanitari e sociali, professionalit\ue0 diverse, diversi attori pubblici e privati, profit e non profit; b) approccio culturale focalizzato non sulla malattia ma sulla persona e il suo progetto di cura e di vita sotto il profilo clinico ma anche con riferimento al contesto familiare, economico, ambientale. Il fine \ue8 la definizione di percorsi diagnostico-terapeutici assistenziali (PDTA) personalizzati che coinvolgano attivamente non solo il paziente, ma anche i caregiver di riferimento. La sua realizzazione deve rispondere a criteri di flessibilit\ue0 e modularit\ue0, con focus sul differenziale fra intervento delineato dal PDTA e intervento pubblico, tenendo conto della diversa declinazione territoriale e delle diverse capacit\ue0 di spesa dei soggetti interessati; c) valorizzazione del momento collettivo e della bilateralit\ue0 quali elementi di contenimento di costi e ampliamento dei tradizionali perimetri di copertura

Embodied perspective-taking indicated by selective disruption from aberrant self motion

Spatial perspective-taking that involves imagined changes in one’s spatial orientation is facilitated by vestibular stimulation inducing a congruent sensation of self-motion. We examined further the role of vestibular resources in perspective-taking by evaluating whether aberrant and conflicting vestibular stimulation impaired perspective-taking performance. Participants (N = 39) undertook either an “own body transformation” (OBT)task, requiring speeded spatial judgments made from the perspective of a schematic figure, or a control task requiring reconfiguration of spatial mappings from one’s own visuo-spatial perspective. These tasks were performed both without and with vestibular stimulation by whole-body Coriolis motion, according to a repeated measures design, balanced for order. Vestibular stimulation was found to impair performance during the first minute post stimulus relative to the stationary condition. This disruption was task-specific, affecting only the OBT task and not the control task, and dissipated by the second minute post-stimulus. Our experiment thus demonstrates selective temporary impairment of perspective-taking from aberrant vestibular stimulation, implying that uncompromised vestibular resources are necessary for efficient perspective-taking. This finding provides evidence for an embodied mechanism for perspective-taking whereby vestibular input contributes to multisensory processing underlying bodily and social cognition. Ultimately, this knowledge may contribute to the design of interventions that help patients suffering sudden vertigo adapt to the cognitive difficulties caused by aberrant vestibular stimulation

Group membership and racial bias modulate the temporal estimation of in-group/out-group body movements

Social group categorization has been mainly studied in relation to ownership manipulations involving highly-salient multisensory cues. Here, we propose a novel paradigm that can implicitly activate the embodiment process in the presence of group affiliation information, whilst participants complete a task irrelevant to social categorization. Ethnically White participants watched videos of White- and Black-skinned models writing a proverb. The writing was interrupted 7, 4 or 1 s before completion. Participants were tasked with estimating the residual duration following interruption. A video showing only hand kinematic traces acted as a control condition. Residual duration estimates for out-group and control videos were significantly lower than those for in-group videos only for the longest duration. Moreover, stronger implicit racial bias was negatively correlated to estimates of residual duration for out-group videos. The underestimation bias for the out-group condition might be mediated by implicit embodiment, affective and attentional processes, and finalized to a rapid out-group categorization

Effects of crustal layering on source parameter inversion from coseismic geodetic data

SUMMARY We study the effect of a superficial layer overlying a half-space on the surface displacements caused by uniform slipping of a dip-slip normal rectangular fault. We compute static coseismic displacements using a 3-D analytical code for different characteristics of the layered medium, different fault geometries and different configurations of bench marks to simulate different kinds of geodetic data (GPS, Synthetic Aperture Radar, and levellings). We perform both joint and separate inversions of the three components of synthetic displacement without constraining fault parameters, apart from strike and rake, and using a non-linear global inversion technique under the assumption of homogeneous half-space. Differences between synthetic displacements computed in the presence of the superficial soft layer and in a homogeneous half-space do not show a simple regular behaviour, even if a few features can be identified. Consequently, also retrieved parameters of the homogeneous equivalent fault obtained by unconstrained inversion of surface displacements do not show a simple regular behaviour. We point out that the presence of a superficial layer may lead to misestimating several fault parameters both using joint and separate inversions of the three components of synthetic displacement and that the effects of the presence of the superficial layer can change whether all fault parameters are left free in the inversions or not. In the inversion of any kind of coseismic geodetic data, fault size and slip can be largely misestimated, but the product (fault length) × (fault width) × slip, which is proportional to the seismic moment for a given rigidity modulus, is often well determined (within a few per cent). Because inversion of coseismic geodetic data assuming a layered medium is impracticable, we suggest that only a case-to-case study involving some kind of recursive determination of fault parameters through data correction seems to give the proper approach when layering is important