11 research outputs found
Combining regional rainfall frequency analysis and rainfall-runoff modelling to derive frequency distributions of peak flows in ungauged basins: a proposal for Sicily region (Italy)
Abstract. In the present study an attempt is made to provide a general Monte Carlo approach for deriving flood frequency curves in ungauged basins in Sicily region (Italy). The proposed procedure consists of (i) a regional frequency analysis of extreme rainfall series, combined with Huff curves-based synthetic hyetographs, for design storms and (ii) a rainfall-runoff model, based on the Time-Area technique, to generate synthetic hydrographs. Validation of the procedure is carried out on four gauged river basins in Sicily region (Italy), where synthetic peak flow frequency curves, obtained by simulating 1000 flood events, are compared with observed values. Results of the application reveal that the proposed Monte Carlo approach is suitable to reproduce with reasonable accuracy the hydrologic response of the investigated basins. Given its relative simplicity, the developed procedure can be easily extended to poorly gauged or ungauged basins
Flood and landslide warning based on rainfall thresholds and soil moisture indexes: the HEWS (Hydrohazards Early Warning System) for Sicily
Abstract. The main focus of the paper is to present a flood and landslide early warning system, named HEWS (Hydrohazards Early Warning System), specifically developed for the Civil Protection Department of Sicily, based on the combined use of rainfall thresholds, soil moisture modelling and quantitative precipitation forecast (QPF). The warning system is referred to 9 different Alert Zones in which Sicily has been divided into and based on a threshold system of three different increasing critical levels: ordinary, moderate and high. In this system, for early flood warning, a Soil Moisture Accounting (SMA) model provides daily soil moisture conditions, which allow to select a specific set of three rainfall thresholds, one for each critical level considered, to be used for issue the alert bulletin. Wetness indexes, representative of the soil moisture conditions of a catchment, are calculated using a simple, spatially-lumped rainfallâstreamflow model, based on the SCS-CN method, and on the unit hydrograph approach, that require daily observed and/or predicted rainfall, and temperature data as input. For the calibration of this model daily continuous time series of rainfall, streamflow and air temperature data are used. An event based lumped rainfallârunoff model has been, instead, used for the derivation of the rainfall thresholds for each catchment in Sicily characterised by an area larger than 50âŻkm2. In particular, a Kinematic Instantaneous Unit Hydrograph based lumped rainfallârunoff model with the SCS-CN routine for net rainfall was developed for this purpose. For rainfall-induced shallow landslide warning, empirical rainfall thresholds provided by Gariano et al. (2015) have been included in the system. They were derived on an empirical basis starting from a catalogue of 265 shallow landslides in Sicily in the period 2002â2012. Finally, Delft-FEWS operational forecasting platform has been applied to link input data, SMA model and rainfall threshold models to produce warning on a daily basis for the entire region
Combining regional rainfall frequency analysis and rainfall-runoff modelling to derive frequency distributions of peak flows in ungauged basins: a proposal for Sicily region (Italy)
Abstract. In the present study an attempt is made to provide a general Monte Carlo approach for deriving flood frequency curves in ungauged basins in Sicily region (Italy). The proposed procedure consists of (i) a regional frequency analysis of extreme rainfall series, combined with Huff curves-based synthetic hyetographs, for design storms and (ii) a rainfall-runoff model, based on the Time-Area technique, to generate synthetic hydrographs. Validation of the procedure is carried out on four gauged river basins in Sicily region (Italy), where synthetic peak flow frequency curves, obtained by simulating 1000 flood events, are compared with observed values. Results of the application reveal that the proposed Monte Carlo approach is suitable to reproduce with reasonable accuracy the hydrologic response of the investigated basins. Given its relative simplicity, the developed procedure can be easily extended to poorly gauged or ungauged basins
Nebulized hypertonic saline containing hyaluronic acid improves tolerability in patients with cystic fibrosis and lung disease compared with nebulized hypertonic saline alone: a prospective, randomized, double-blind, controlled study
Background: Hypertonic saline inhalation has been shown to be effective in patients with cystic fibrosis and lung disease. However, adverse events including marked airway narrowing are reported and a bronchodilator must be given before the administration of the product. Methods: We carried out a prospective, randomized, double-blind, parallel-group, controlled study of a hypertonic saline solution containing hyaluronic acid (Hyaneb) versus standard hypertonic saline therapy to assess whether the presence of hyaluronic acid would improve the tolerability of hypertonic saline. Results and conclusions: The results showed that nebulized Hyaneb was more effective in reducing the need for β 2 bronchodilators and caused a significant reduction in the incidence of adverse effects compared with nebulized hypertonic saline solution alone. Its safety profile indicates that Hyaneb can be used for the treatment of lung disease in cystic fibrosis
Intranasal Administration of a TRAIL Neutralizing Monoclonal Antibody Adsorbed in PLGA Nanoparticles and NLC Nanosystems: An In Vivo Study on a Mouse Model of Alzheimerâs Disease
Alzheimerâs disease (AD) is a neurodegenerative disorder that progressively compromises cognitive functions. Tumor necrosis factor (TNF)-Related Apoptosis Inducing Ligand (TRAIL), a proinflammatory cytokine belonging to the TNF superfamily, appears to be a key player in the inflammatory/immune orchestra of the AD brain. Despite the ability of an anti-TRAIL monoclonal antibody to reach the brain producing beneficial effects in AD mice, we attempted to develop such a TRAIL-neutralizing monoclonal antibody adsorbed on lipid and polymeric nanocarriers, for intranasal administration, in a valid approach to overcome issues related to both high dose and drug transport across the bloodâbrain barrier. The two types of nanomedicines produced showed physico-chemical characteristics appropriate for intranasal administration. As confirmed by enzyme-linked immunosorbent assay (ELISA), both nanomedicines were able to form a complex with the antibody with an encapsulation efficiency of â99%. After testing in vitro the immunoneutralizing properties of the nanomedicines, the latter were intranasally administered in AD mice. The antibodyânanocarrier complexes were detectable in the brain in substantial amounts at concentrations significantly higher compared to the free form of the anti-TRAIL antibody. These data support the use of nanomedicine as an optimal method for the delivery of the TRAIL neutralizing antibody to the brain through the nose-to-brain route, aiming to improve the biological attributes of anti-TRAIL-based therapy for AD treatment
Enhancing triboelectric performances of electrospun poly(vinylidene fluoride) with graphene oxide sheets
Poly(vinylidene fuoride) (PVDF) is an easy processable and electroactive polymer, widely investigated for the preparation
of electrospun membranes for triboelectric nanogenerators (TENG). The presence of graphene oxide (GO) fllers into the
PVDF nanofbers, used as electroactive membranes in TENGs, has been reported to improve their performances as GO can
act as charge trapping site. Nevertheless, the addition of GO also afects the dielectric and rheological properties of the
spinning dispersions and the role of such parameters on the nanofber morphology has not been clarifed yet. In this work,
we investigated the efect of GO on the electrospinning process of PVDFâGO dispersions. In particular, we found that the
addition of GO in PVDF solutions modifes their rheological properties by increasing their viscosity and enhancing their
shear thinning behavior. Consequently, compared to the PVDF solution, the electrospinning process of PVDFâGO composite
solutions results in more homogenous and thinner nanofbers. Both PVDF and PVDFâGO nanofbers showed a similar fraction of electroactive PVDF β-phase, which was higher than 80%. This demonstrates that the relative content of β-phase is not
the main responsible for the observed improvement in TENG performances. Therefore, besides acting as a charge trapping
site, the presence of GO also shrinks the PVDFâGO fbers diameter, resulting in an electrospun membrane with increased
specifc surface area compared to the PVDF counterpart