Operativni sustav za prognoziranje hipoksije u sjevernom Jadranu

The northern Adriatic Sea (NA), the northernmost region of the Mediterranean Sea, is affected by strong anthropogenic pressure (e.g., tourism, fisheries, maritime traffic, discharge from agriculture and industry), superimposed to a large river runoff. The consequent pressure exerted on the NA ecosystem either triggers or worsens massive mucilage insurgence, harmful algal blooms, eutrophication and even anoxic/hypoxic events. This work focuses on the anoxic/hypoxic events. During the summer-autumn period, the NA is often exposed to these events, which can be categorised as either coastal (relatively frequent south of the Po River delta during the summer) and offshore (rare, affecting wider areas). In order to improve our knowledge about these processes and to meet the needs of local governments and decision makers, an operational system for monitoring and forecasting anoxic and hypoxic events has been set up in the framework of the EU LIFE "EMMA" project. The system is composed of a meteo-oceanographic buoy; a numerical prediction system based on the Regional Ocean Modelling System (ROMS), including a Fasham-type module for biogeochemical fluxes; and periodic oceanographic surveys. Every day since June 2007, the system provides 3-hourly forecasts of marine currents, thermohaline and biogeochemical fields for the incoming three days. The system has demonstrated its ability to produce accurate temperature forecasts and relatively good salinity and dissolved oxygen forecasts. The Root Mean Square Error of the dissolved oxygen forecast was largely due to the mean bias. The system is currently being improved to include a better representation of benthic layer biogeochemical processes and several adjustments of the model. While developing model improvements, dissolved oxygen forecasts were improved with the removal of the 10-day mean bias.Sjeverni Jadran (NA), najsjeverniji dio Sredozemnog mora, pod utjecajem je jakog antropogenog djelovanja (poput turizma, ribarenja, morskog prometa, istjecanje onečišćujućih tvari u poljoprivredi i industriji) te dodatno, velikog dotoka rijeka. Posljedično, djelovanje na NA ekosustav potiče ili pojačava uzdizanje sluzavih nakupina, štetno cvjetanje algi, eutrofikaciju pa čak i događaje anoksije/hipoksije. Ovaj se rad fokusira na anoksiju/hipoksiju. Tijekom ljetno-jesenskog razdoblja, NA je često izložen ovim doga|ajima, koji se mogu kategorizirati kao obalni (relativno učestali južno od delte rijeke Po ljeti) ili udaljeni od obale (rijetki, zahvaćajući šira područja). Kako bi poboljšali poznavanje tih procesa te zbog potreba lokalne uprave, uspostavljen je operativni sustav za praćenje i prognoziranje anoksije i hipoksije u okviru EU LIFE "EMMA" projekta. Sustav se sastoji od meteorološko-oceanografske plutače; sustava za numeričku prognozu, koji se temelji na regionalnom oceanografskom modelu (ROMS), uključujući modul Fasham-tipa za biogeokemijske tokove; i periodičnim oceanografskim istraživanjima. Svakog dana, počev od lipnja 2007, sustav omogućava 3-satne prognoze morskih struja te termohalina i biogeokemijska polja za sljedeća tri dana. Sustav se pokazao sposobnim za davanje točnih prognoza temperature i relativno dobrih prognoza saliniteta i otopljenog kisika. Korijen srednje kvadratne pogreške prognoziranog otopljenog kisika postojao je uglavnom zbog srednje pristranosti (biasa). Sustav je trenutno poboljšan tako da uključuje bolji prikaz biogeokemijskih procesa u području sloja bentosa i nekoliko prilagodba modela. Tijekom poboljšavanja modela, uklanjanjem 10-dnevne srednje pristranosti (biasa) poboljšane su prognoze otopljenog kisika

Bevande da tenere sotto controllo: gli Energy Drinks

Nel mondo si consumano globalmente circa 260 miliardi di litri di bibite preconfezionate, di cui 10 miliardi di energy drinks, diventati negli ultimi anni sempre più popolari soprattutto tra i giovani, che il più delle volte li associano ad alcolici e superalcolici. Nonostante l'enorme popolarità a livello mondiale non tutti i paesi ne hanno concesso l'autorizzazione alla vendita. Infatti, nati come bevande destinate a fornire una maggiore quantità di energia rispetto alle bevande tradizionali, nella loro composizione riportano una serie di ingredienti che, in un organismo in evoluzione, quale quello degli adolescenti, possono dare origine ad una serie di effetti indesiderati

Impact of Control Point Angular Separation on the Dosimetric Accuracy of VMAT Plans

n/

Zn-air battery with a PEDOT: PSS cathode as a viable option for wearable medical devices

For medical sensing devices, such as wound-healing patches, it is necessary to provide wearable and long-term usable power supply. This calls for cost-effective, lightweight batteries. We propose here a metal-air battery composed out of a Zn anode and a poly(3,4-ethylene dioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) cathode. A PEDOT: PSS layer was created by film deposition and used as cathode without binders because of its high-adhesion. Two film types of different thicknesses were analysed. The effect of a 1-butyl- 3-methylimidazolium octyl sulfate ionic liquid, also reported to act as a stabilizer, on the electric performance has been assessed. The electrodes presented low-surface resistivity and a considerable discharge capacity. The results showed that PEDOT: PSS acts properly as an O2 redox reaction matrix and conducting binder in the air electrode, implying that PEDOT: PSS films are suitable for Zn-Air batteries’ cathode. Moreover, we demonstrate a polymer-enabled biocompatible Zn-air battery device with a total thickness of approximately 2 mm, easy to assemble, light-weight and cost-effective. Graphical abstract: [Figure not available: see fulltext.]SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Impact of currents on surface flux computations and their feedback on dynamics at regional scales

A twin numerical experiment was conducted in the seas around the island of Sardinia (Western Mediterranean) to assess the impact, at regional and coastal scales, of the use of relative winds (i.e., taking into account ocean surface currents) in the computation of heat and momentum fluxes through standard (Fairall et al., 2003) bulk formulas. The Regional Ocean Modelling System (ROMS) was implemented at 3 km resolution in order to well resolve mesoscale processes, which are known to have a large influence in the dynamics of the area. Small changes (few percent points) in terms of spatially averaged fluxes correspond to quite large differences of such quantities (about 15 %) in spatial terms and in terms of kinetics (more than 20 %). As a consequence, wind power input <i>P</i> is also reduced by ~ 14 % on average. Quantitative validation with satellite SST suggests that such a modification of the fluxes improves the model solution especially in the western side of the domain, where mesoscale activity (as suggested by eddy kinetic energy) is stronger. Surface currents change both in their stable and fluctuating part. In particular, the path and intensity of the Algerian Current and of the Western Sardinia Current (WSC) are impacted by the modification in fluxes. Both total and eddy kinetic energies of the surface current field are reduced in the experiment where fluxes took into account the surface currents. The main dynamical correction is observed in the SW area, where the different location and strength of the eddies influence the path and intensity of the WSC. Our results suggest that, even at local scales and in temperate regions, it would be preferable to take into account such a contribution in flux computations. The modification of the original code, substantially cost-less in terms of numerical computation, improves the model response in terms of surface fluxes (SST validated) and it also likely improves the dynamics as suggested by qualitative comparison with satellite data

Chemical stability and reversibility of PEDOT:PSS electrodes in view of low-cost biocompatible cellulose-assisted biosensors

The increasing necessity for small electronics and wireless technologies in energetic devices, such as batteries or supercapacitors and in medical devices, such as sensors, drug delivery systems, calls for new materials, devices and preparation methods. In this work, the possibility of using a PEDOT:PSS hydrogel film as a cathode for a biocompatible cellulose-assisted biosensing device has been explored. The effect of film formulation and preparation method on the electrical conductivity is investigated, i.e. adding a cross-linker and different solvent additives on one side and adding an ionic liquid with and without a metal salt on the other side, for two film thicknesses. The chemical composition of the electrode is studied as a function of the used formulation as well as after being used as cathode in the biosensing device. It appeared that the electrode based on the cross-linker was mechanically robust, but suffered in electrical conductivity, despite the enhancement provided by the solvent additives. The electrode based on the ionic liquid showed a considerable increase in electrical performance, although the mechanical stability was not easy to maintain. The thin film showed a higher electrical conductivity. Although the metal salt enhanced somewhat further the electrical performance, the mechanical one suffered considerably. An application of the PEDOT:PSS electrode as cathode in a biosensing device showed promising results. Concentrations of the order of μl were measured without difficulty and the cathode seemed to be chemically stable and therefore reutilisable, opening future applications in reutilisable low-cost wearable biosensors and corresponding wearable batteries. © 2021 Elsevier Lt

Filament formation and evolution in buoyant coastal waters: Observation and modelling

This paper presents a detailed analysis of the formation and subsequent evolution of filament-like structures observed in a relatively small area of the mid-Tyrrhenian Sea (Mediterranean Sea). The filament dynamics and potential impact on the cross-shelf exchange budget are investigated based on a combined use of remote sensing imagery, in situ data and numerical modelling. The complexity of these phenomena is shown by focusing on four distinct events that led to cross-shelf transport, each representative of a different dynamic process and a distinct expected impact on the coastal area. A systematic analysis of available observations for the years 1998-2006 underlines the role of the interplay of atmospheric freshwater fluxes, river loads and wind stress variations, which may create favourable conditions for the convergence of shelf waters (particularly at coastal capes) and the subsequent formation of short-lived filaments along the coast. The response of the buoyant coastal waters to periods of wind reversal and fluctuating freshwater discharge rates is examined through idealised Regional Ocean Modeling System (ROMS) simulations. The filaments observed in remote sensing imagery were well reproduced by the numerical exercise, where the filaments appear as organised submesoscale structures that possess high relative vorticity and develop at the river mouths or adjacent capes. In both scenarios, the filaments appear largely determined by (i) the presence of a buoyancy anomaly, (ii) the angle between the wind pulse direction and the coast and (iii) irregularities in the coastal profile. The ensemble of results suggests that the occurrence of such transient, intense structures may contribute considerably to the biological variability and cross-shelf exchange in coastal areas with similar traits. © 2012 Elsevier Ltd