1,721,101 research outputs found
Control of Hydrological Seasonal Variability of Ash-fall Pyroclastic Deposits on Rainfall Triggering Debris Flows in Campania (Southern Italy)
No full textAsh-fall pyroclastic deposits covering Campanian mountain slopes (southern Italy) are very prone to instability under heavy and prolonged rainfall. In such a geo-hazard framework, to understand hydrological dynamics of pyroclastic mantle is a further step toward the assessment of rainfall thresholds and landslide hazard. In this research, the hydrological and stability modelling of representative ash-fall pyroclastic soil mantled slopes of the Sarno Mountains is proposed to assess the role of seasonal hydrological variability of the pyroclastic cover on rainfall triggering debris flows. The approach is based on the numerical modelling, from seasonal to inter-annual timescales, of unsaturated/ saturated flows occurring into the pyroclastic mantle upslope of a source area of a debris flow. Modelling results were calibrated by means of field measurements achieved by a monitoring station equipped with tensiometers and Watermark sensors. Among the main results, the recorded pressure head time series showed a dominant unsaturated condition and a very relevant decrease in the summer season, whose effects are not limited to the root zone but extended down to the bedrock interface, about 4 meter deep. This seasonal hydrological regime of the ash-fall pyroclastic mantle was correlated both to the distinctive water retention properties of pyroclastic soils and to the existence of a deciduous forest, which concentrates the evapotranspiration demand during the dry season. Hydrological and stability modeling of the representative slopes allowed the reconstruction of deterministic rainfall thresholds for both dry and wet seasons and the assessment of the significant predisposing role of antecedent hydrological conditions to slope instability during short and heavy rainstorms
Telerehabilitation after Total Knee Replacement: Preliminary Cost-Utility Analysis of an Innovative Device
No full textDisruptive innovation in Healthcare: breaking the old patterns of business modelling and Health Technology Assessment. Preliminary results for the assessment of an innovative knee Telerehabilitation device in Tuscany.
No full textOn state and inertial parameter estimation of free-falling planar rigid bodies subject to unsche dule d frictional impacts
Full text linkThis paper addresses the problem of simultaneous state estimation and inertial and frictional parameter identification for planar rigid-bodies subject to unscheduled frictional impacts. The aim is to evaluate to what level of accuracy, given noisy captured poses of an object free-falling under gravity and impacting the surrounding environment, it is conceivable to reconstruct its states, the sequence of normal and tangential impulses and, concurrently, estimate its inertial properties along with Coulomb’s coefficient of friction at contacts.
To this aim we set up a constrained nonlinear optimization problem, where the unscheduled impacts are handled via a complementarity formulation. To assess the validity of the proposed approach we test the identification results both (i) with respect to ground truth values produced with a simulator, and (ii) with respect to real experimental data. In both cases, we are able to provide accurate/realistic estimates of the inertia-to-mass ratio and friction coefficient along with a satisfactory reconstruction of systems states and contact impulses
Hydrological behavior of ash-fall pyroclastic soil mantled slopes of the Sarno Mountains (Campania - southern Italy)
No full textThe instability of ash-fall pyroclastic deposits that mantle mountain
ranges around the Mount Somma-Vesuvius (Campania, southern Italy) are well known to represent a main geological hazard due to their frequent involvement in shallow flow-like landslides, triggered by high-intensity and prolonged rainfall. In such a geomorphological framework, which is similar to other mountain areas that surround volcanic centers of the world, the comprehension of hydrological dynamics occurring into
pyroclastic deposits is a key factor for assessing and modelling the
landslide hazard. Despite the general relevance of hydrological analysis in studying shallow landslides, this type of approach is particularly
significant for pyroclastic soils due to their special hydrological properties
and complex stratigraphic settings. Along with this goal, in a test area of
the Sarno Mountains, upslope of a debris flow source area, a monitoring
station was installed to assess hydrological processes that predispose and lead to landslide triggering. Monitoring data, covering about three
hydrological years (Dec. 2010 - Dec. 2013), showed a regime of pore
pressures always ranging in unsaturated conditions. Marked seasonal and interannual variations of pore pressure were observed at different depths with respectively delayed and damped dynamics. These observations were correlated to rainfall patterns and the evapotranspiration regime, which is concentrated during the activity period of the existing deciduous forest. Results of this approach allow understanding hydrological processes at slope scale, to set and calibrate numerical models for estimating rainfall thresholds by a deterministic approach as well as to assess landslide hazard
Interactive business models for Telerehabilitation after Total Knee Replacement: Preliminary results from Tuscany
No full textSpatial modeling of ash-fall pyroclastic deposits for the assessment of rainfall thresholds triggering debris flows in the Sarno and Lattari mountains (Campania, southern Italy)
No full textAmong the mountain ranges that surround the Somma-Vesuvius volcano (southern Italy), the Sarno and Lattari mounts are the closest and those where the highest thicknesses of ash-fall pyroclastic soils were deposited. Therefore, pyroclastic soil mantled slopes along these physiographic units are the most affected by rainfall-induced debris flows that, in these areas, represent one of the major geohazards of Italy. According to their strong societal impact, many studies were focused on the assessment of early warning systems based on the analysis of hydrological forcing that trigger debris flows. In this research, an attempt to consider the effect of spatial variability of ash-fall pyroclastic soil deposits and the related stratigraphic settings was carried out to assess rainfall conditions leading to initial slope instabilities that trigger debris flows. A key point was to model the spatial distribution of ash-fall pyroclastic deposits by considering the orientation of the dispersion axes of the main Plinian eruptions, the distance from the eruptive centre and the slope angle. The resulted conceptual geomorphological models, reconstructed for both the considered mountain ranges, were used to simulate hydrological processes that determine initial slope instabilities and to assess the related rainfall thresholds, taking also into account antecedent conditions
Budget impact of FVIII concentrates taking into account the incidence of de novo inhibitor formation in PTPs: a breakeven analysis applied to ADVATE© in the Italian context
No full textTelerehabilitation after Total Knee Replacement: Preliminary Cost-Effectiveness Analysis of an Innovative Device
No full textA cost-effectiveness analysis for total knee arthroplasty telerehabilitation: proof of concept of a decision model
No full textOBJECTIVES: The study aims to assess the cost-effectiveness of telerehabilitation for Total Knee Arthroplasty (TKA) patients in Italy. TKA was performed 64,936 times in Italy in 2012, reasonably leading to the same number of rehabilitation processes. The most recent cost analysis showed rehabilitation to account for Euro 158 millions per year. Therefore, new strategies aiming at optimizing resources and preserve patients’ wellbeing are claimed.
METHODS: A four-state Markov model (successful TKA; revision; successful revision; death) forecasted costs and clinical outcome over 10 years (cycle length: 1 year) for 1,000 individuals undergoing usual care rehabilitation (UC) or a mixed UC-telerehabilitation (UC-T) program. Published literature provided transition probabilities and clinical outcome (active knee flexion Range Of Motion-ROM); while UC and telerehabilitation costs were estimated through Italian tariffs and panel of experts. Each surgery was assumed to lead to rehabilitation or telerehabilitation, resulting in direct medical and indirect costs (human capital approach). Results were adjusted applying half-cycle correction method and discount rate of 3%. A Probabilistic Sensitivity Analysis (PSA) described parameters uncertainty and results were reported using Incremental Cost-Effectiveness Ratio (ICER) from society and Italian-NHS perspective.
RESULTS: Expected mean health care costs for UC were 1,253.2€/patient over ten years, and UC-T costs were on average 33.7€/patient higher (95% CI €10.8). ROM-degrees for UC and UC-T were respectively 24.5 and 26.8 (mean difference=2.3, 95% CI 0.002). The resulting ICER was 14.5€/ROM-degree (Italian and NHS perspective).Adopting a societal perspective, UC-T was more effective yet appeared cheaper than UC (respectively 1,429 and 1,457€/patient, mean difference -28€/patient (95% CI €10.8)).
CONCLUSIONS: Although the preliminary results have shown that UC-T could be a cost-saving procedure if societal perspective is adopted, these findings are uncertain due to the model assumptions. Therefore, further investigations with patients’ level data and generic outcome measures (e.g. QALY) are required to draw definitive conclusions about cost-effectiveness in telerehabilitation
- …
