Risk-based tunnel design for consequences of road accidents. The role of tunnel lenght

Tunnel extension is an under-analysed variable in road tunnel accidents despite being a dimensioning parameter for the purposes of users’ safety according to Directive 2004/54/EC. Recent studies have shown a correlation between the tunnel length and consequences of accidents. The analysis of fire events which occurred in tunnels indicates that in many cases fires are triggered by road accidents. By analysing the road accidents in Italy, the study aims to assess the relative risk of accidents with serious consequences for different classes of road tunnels. The second objective was to assess, using a vehicle type (or size) approach, the corresponding probability of accidents involving vehicles or trucks and special vehicles resulting in serious consequences (domino effect). We analysed the Italian National Institute of Statistics (Istat) dataset on tunnel accidents which occurred between 2018 and 2020 on Italian public roads, involving at least one vehicle. Of these, we extracted tunnel accidents, classified by tunnel length and estimated the corresponding probability of serious consequences. The analysis identified 1,885 case studies of tunnel accidents that occurred in approximately 265 long tunnels and 450 short tunnels and underpasses. Compared with “controls”, “size” was found to be more than double in long tunnels where the related probability of serious accident consequences exceeded 50% more than those of short tunnels. We found that the related probability associated with serious accident consequences in tunnels over 500 m in length was higher than in short tunnels, except for trucks and special vehicles. Road accidents and research on risk evaluation of the effects associated with long and short tunnels are rare. The study aims to fill these gaps

Risk based tunnel design by vehicle involved in road crashes. Models and tunnel length

Between 2018 and 2020, in the approximately 2,600 km of Italian road tunnels, 2,899 people were injured and 60 died in 1,885 road accidents. The accident frequency was lower than on open roads, while the injury/fatality rate was higher. Using the recursive partitioning and regression trees method (rpart), we developed two accident models useful for predicting the probability of involvement of "vehicle type" in short and long tunnels. Variables such as the type of accident, the circumstances, the type of road, the carriageway, the time of the accident, the journey purpose (whether work-related or not), and the length of the tunnel defined the nodes and paths of the regression tree associated with a vehicle type involved. The “road type” was the best predictors for short tunnels while the “journey purpose” was the best predictor for long tunnels. The most important result of the study refers to the similarity between the probability of an accident in short and long tunnels for a specific segment of road users: commuting and non-commuting car drivers and drivers of heavy goods vehicles on-duty. The study showed that this road user segment in short tunnels has an accident probability half that observed in long tunnels

Impact of solid lipid nanoparticles on 3T3 fibroblasts viability and lipid profile: The effect of curcumin and resveratrol loading

This study focused on the impact in 3T3 fibroblasts of several types of empty and curcumin- and resveratrol-loaded solid lipid nanoparticles (SLN) on cell viability and lipid metabolism in relation to their lipid content and encapsulated drug. SLN, prepared by hot homogenization/ultrasonication, were characterized with respect to size, polydispersity index, and zeta potential. Compritol® 888 ATO at different concentrations (4%, 5%, and 6% wt/wt) was chosen as lipid matrix while Poloxamer 188 (from 2.2% to 3.3% wt/wt) and Transcutol (TRC; 2% or 4%) were added as nanoparticle excipients. Prepared SLN were able to encapsulate high drug amount (encapsulation efficiency percentage of about 97–99%). All empty SLN did not show cytotoxicity (by MTT assay, at 24 h of incubation) in 3T3 cells independently of the lipid and TRC amount, while a viability reduction in the range 5–11% and 12–27% was observed in 3T3 cells treated with curcumin-loaded and resveratrol-loaded SLN, respectively. SLN without TRC did not affect cell lipid metabolism, independently from the lipid content. Empty and loaded SLN formulated with 4% of Compritol and 4% of TRC significantly affected, after 24 h of incubation at the dose of 5 μl/ml, cell polar lipids (phospholipids and free cholesterol) and fatty acid profile, with respect to control cells. Loaded compounds significantly modulated the impact of the corresponding empty formulation on cell lipids. Therefore, the combined impact on lipid metabolism of SLN and loaded drug should be taken in consideration in the evaluation of the toxicity, potential application, and therapeutic effects of new formulations

Zoxamide accumulation and retention evaluation after nanosuspension technology application in tomato plant

BACKGROUND: Low water solubility of pesticide requires formulations with high levels of stabilizers and organic solvents. Moreover, only 0.1% of the applied pesticides formulation reaches the target, while 99.9% spreads in the surrounding environment. Therefore, there is the need for more efficient and environmentally sustainable alternatives. RESULTS: Zoxamide (ZO) nanosuspension was prepared through a media milling technique by using the stabilizer polysorbate 80. The thin and acicular crystals obtained, showed particle size of 227 nm, polydispersion index of 0.247 and zeta potential of −28 mV. Dimensional data and morphology of ZO nanocrystals alone, on tomato leaves and berries, were confirmed by scanning electron microscopy. The reduction in size for ZO crystals obtained after the milling process increased pesticide water solubility till 39.6 mg L−1, about 1.6 the solubility obtained with a conventional commercial formulation. Field and dip contamination trials performed on tomato plants showed the nanosuspension's ability to increase ZO deposition and accumulation versus a coarse ZO suspension and commercial formulation, respectively. CONCLUSIONS: The nanoformulation proposed, resulted in low cost and was easy to make. Moreover, the organic solvent-free composition together with a low surfactant addition assured a minor environmental impact. Finally, the increased retention and deposition of the fungicide can reduce the amounts of ZO formulation applied to tomatoes