Development of a Methodology for the Identification of High Emitting Mobile Sources in Narrow and Deep Street Canyons

In urban areas transport represents a significant source of atmospheric pollutants and greenhouse gases (GHG). In the case of vehicular transport, a significant contribution to total emissions is given by a category of vehicles with excessively high emissions of one or more pollutants defined as high emitting vehicles (high-emitters). High emitters can contribute a disproportionally way to total emissions of many airborne pollutants (NOx, COV, PM and GHGs). Remote sensing (RS) techniques have been developed with the aim to identify high emitterss but until now they have found only few practical applications. Among RS technologies, point sampling (PS) is the most promising for implementation in narrow and deep street canyons due to the limited impact on both pedestrians and architecture and the small space occupancy. In this paper we present results of preliminary monitoring campaigns carried out in a narrow and deep street canyon in Naples (Italy) in low-traffic conditions. Fine particles (FPs) concentration (20-1000 nm) were monitored using a condensation particle counter (CPC). Time patterns of FPs concentration have been analyzed by a code developed in MATLAB to identify FP concentration peaks and successively to attribute each identified peak to a specific vehicle. To study the effect of operating conditions (wind speed and direction) on the plume formed by vehicle exhausts, CFD simulations have been also carried out. Results show good performances of the code in the identification of FPs peaks and a limited effect of ambient parameters on the dispersion of the plumes inside the street canyon studied

The rate of sedimentation from turbulent suspension: an experimental model with application to pyroclastic density currents and discussion on the grain-size dependence of flow runout

Large‐scale experiments generating ground‐hugging multiphase flows were carried out with the aim of modelling the rate of sedimentation, of pyroclastic density currents. The current was initiated by the impact on the ground of a dense gas‐particle fountain issuing from a vertical conduit. On impact, a thick massive deposit was formed. The grain size of the massive deposit was almost identical to that of the mixture feeding the fountain, suggesting that similar layers formed at the impact of a natural volcanic fountain should be representative of the parent grain‐size distribution of the eruption. The flow evolved laterally into a turbulent suspension current that sedimented a thin, tractive layer. A good correlation was found between the ratio of transported/sedimented load and the normalized Rouse number of the turbulent current. A model of the sedimentation rate was developed, which shows a relationship between grain size and flow runout. A current fed with coarser particles has a higher sedimentation rate, a larger grain‐size selectivity and runs shorter than a current fed with finer particles. Application of the model to pyroclastic deposits of Vesuvius and Campi Flegrei of Southern Italy resulted in sedimentation rates falling inside the range of experiments and allowed definition of the duration of pyroclastic density currents which add important information on the hazard of such dangerous flows. The model could possibly be extended, in the future, to other geological density currents as, for example, turbidity currents

Conceptual Study of a Thermal Storage Module for Solar Power Plants with Parabolic Trough Concentrators

The thermal storage technology (TSE) has a relevant strategic importance for the success of solar plants devoted to electric energy and heat production. The major benefits in the use of storage include higher efficiency and reduction in the mean levelled cost of the electric energy unit (LEC). Sensible heat storage systems within solid media have been identified, both technically and economically, as a very promising solution. The development of such a storage technology, adopting concrete, could reduce the specific cost to less than 20\u20ac per kWh of thermal capacity; additionally, such a solution is suitable for small-medium size plants with a power ranging from 1 MW to 5 MW, to be easily introduced in the Italian territory and with reduced operational and maintenance needs. In large size CSP systems, as the ARCHIMEDE plant built by ENEL with ENEA technology, a high temperature fluid storage (between 400 and 500\ub0C) is required. Such a temperature seems at present not adequate to allow for adopting concrete, whereas the production of concrete able to sustain 250-300\ub0C appears as a reachable objective. It is supposed to study a storage system characterised by a parallelepiped structure with appropriate section, selfbearing and supported on its major axis, as well as by a piping system directing the thermovector fluid within the cemented matrix

High innate attractiveness to black targets in the blue blowfly, Calliphora vomitoria (L.) (Diptera: Calliphoridae)

Calliphora vomitoria is a myiasis-causing fly in many animal species including humans. The control of blowflies is still anchored on the use of chemicals. However, mass trapping and lure-and-kill techniques represent a promising alternative to pesticides. Visual and olfactory cues are the main stimuli routing the fly's landing behavior. Notably, color attractiveness has been barely explored in flies of medical and veterinary importance, with special reference to blowflies. In this study, we investigated the innate color preferences in C. vomitoria adults, testing binary combinations of painted targets under laboratory conditions. The identity of tested species C. vomitoria was confirmed by DNA sequencing (18S and cox1 genes). C. vomitoria flies showed a significant preference for black colored targets in all tested binary color combinations, after 5, 15, 30 and 60 min of exposure. Black targets were significantly preferred over blue, red, yellow and white ones. Spectral characteristics of all tested color combinations were quantified and the innate attraction of blowflies towards black targets was discussed in relation to their behavioral ecology. To the best of our knowledge, this is the first report on innate color preferences in the Calliphora genus. Our findings can be useful to develop new, cheap and reliable monitoring traps as well as â\u80\u9clure and killâ\u80\u9d tools to control blowfly pests

Molecular determinants for the activating/blocking actions of the 2H-1,4-benzoxazine derivatives, a class of potassium channel modulators targeting the skeletal muscle KATP channels

The 2H-1,4-benzoxazine derivatives are modulators of the skeletal muscle ATP-sensitive-K+ channels (KATP), activating it in the presence of ATP but inhibiting it in the absence of nucleotide. To investigate the molecular determinants for the activating/blocking actions of these compounds, novel molecules with different alkyl or aryl-alkyl substitutes at position 2 of the 1,4-benzoxazine ring were prepared. The effects of the lengthening of the alkyl chain and of branched substitutes, as well as of the introduction of aliphatic/aromatic rings on the activity of the molecules, were investigated on the skeletal muscle KATP channels of the rat, in excised-patch experiments, in the presence or absence of internal ATP (10 -4 M). In the presence of ATP, the 2-n-hexyl analog was the most potent activator (DE50 = 1.08 × 10-10 M), whereas the 2-phenylethyl was not effective. The rank order of efficacy of the openers was 2-n-hexyl ≥2-cyclohexylmethyl >2-isopropyl = 2-n-butyl = 2-phenyl ≥ 2-benzyl = 2-isobutyl analogs. In the absence of ATP, the 2-phenyl analog was the most potent inhibitor (IC50 = 2.5 × 10-11 M); the rank order of efficacy of the blockers was 2-phenyl ≥ 2-n-hexyl > 2-n-butyl > 2-cyclohexylmethyl, whereas the 2-phenylethyl, 2-benzyl, and 2-isobutyl 1,4-benzoxazine analogs were not effective; the 2-isopropyl analog activated the KATP channel even in the absence of nucleotide. Therefore, distinct molecular determinants for the activating or blocking actions for these compounds can be found. For example, the replacement of the linear with the branched alkyl substitutes at the position 2 of the 1,4-benzoxazine nucleus determines the molecular switch from blockers to openers. These compounds were 100-fold more potent and effective as openers than other KCO against the muscle KATP channels. Copyright © 2008 The American Society for Pharmacology and Experimental Therapeutics