Groundwater redox conditions and conductivity in a contaminant plume from geoelectrical investigations

International audienceAccurate mapping of the electrical conductivity and of the redox potential of the groundwater is important in delineating the shape of a contaminant plume. A map of redox potential in an aquifer is indicative of biodegradation of organic matter and of concentrations of redox-active components; a map of electrical conductivity provides information on the mineralisation of the groundwater. Both maps can be used to optimise the position of pumping wells for remediation. The self-potential method (SP) and electrical resistivity tomography (ERT) have been applied to the contaminant plume associated with the Entressen landfill in south-east France. The self-potential depends on groundwater flow (electrokinetic contribution) and redox conditions ("electro-redox" contribution). Using the variation of the piezometric head in the aquifer, the electrokinetic contribution is removed from the SP signals. A good linear correlation (R2=0.85) is obtained between the residual SP data and the redox potential values measured in monitoring wells. This relationship is used to draw a redox potential map of the overall contaminated site. The electrical conductivity of the subsoil is obtained from 3D-ERT analysis. A good linear correlation (R2=0.91) is observed between the electrical conductivity of the aquifer determined from the 3D-ERT image and the conductivity of the groundwater measured in boreholes. This indicates that the formation factor is nearly homogeneous in the shallow aquifer at the scale of the ERT. From this correlation, a map of the pore water conductivity of the aquifer is obtained. Keywords: self-potential, redox potential, electrical resistivity tomography, fluid conductivity, contaminant plum

A methodological framework for the economic assessment of ict-tools for occupants’ engagement

The concept of smartness in building dates to the 1970s, but, in face of the breakthrough technological developments, a new notion of smart building is currently recognized. We talk about ambient intelligence, referring to a building which is responsive to the needs of the occupants and of the energy system. An ambient-intelligent building is human-centric; new services and interfaces are provided to the buildings occupants to learn and set their preferences, with a positive impact on their comfort level and satisfaction with the indoor environmental quality. ICT and IoT are part of the enabling technologies to exploit the potentials of smart buildings, by unlocking the capability of buildings to interact with the system they belong to. To bolster the diffusion of new technologies, methodologies to get quantitative results proving their effectiveness should be provided. In this paper the application of a well-established economic evaluation tool, the so-called Cost-Benefit Analysis, to the case of the deployment of new ICT-tools for occupants’ engagement is presented. The methodology is adopted within the H2020 Mobistyle project, where two levels of the evaluation are identified: the whole project level and the single demo case one. The purpose of the methodology is to assess the effectiveness of the adoption of the ICT-tools in producing economic value in terms of benefits for the occupants and the society. Some preliminary results of its application to the Italian case study are also presented, showing a positive socio-economic balance since the beginning of the deployment

Bank lending in uncertain times

We study the impact of economic uncertainty on the supply of bank credit using a monthly dataset that includes all loan applications submitted by a sample of 650,000 Italian firms between 2003 and 2012. We find that an increase in aggregate uncertainty has three effects. First, it reduces banks' likelihood to accept new credit applications. Second, it lengthens the time firms have to wait for their loans to be released. Third, it makes banks less responsive to fluctuations in short-term interest rates, weakening the bank lending channel of monetary policy. The influence of uncertainty is relatively stronger for poorly capitalized lenders and geographically distant borrowers

Land-use history and topographic gradients as driving factors of subalpine Larix decidua forests

none6restrictedMatteo Garbarino;Emanuele Lingua;Peter J. Weisberg;Alessandra Bottero;Fabio Meloni;Renzo MottaMatteo, Garbarino; Lingua, Emanuele; Peter J., Weisberg; Alessandra, Bottero; Fabio, Meloni; Renzo, Mott

Un’analisi dei tram di Torino: effetti della priorità semaforica ed ITS sui consumi energetici

Nello studio condotto sono stati raccolti ed elaborati dati relativi alla cinematica e ai consumi energetici di un campione dei tram attualmente in servizio sulla linea 4 di Torino, al fine di stimare il beneficio energetico atteso dalla priorità semaforica. L’intera flotta di mezzi operanti sulle linee gestite dalla GTT è monitorata costantemente al fine di garantire la regolarità del servizio e gestire nel minor tempo possibile eventuali guasti ed emergenze. A ogni operatore della centrale operativa è affidata la gestione e il monitoraggio di alcune linee, raffigurate graficamente su terminali delle postazioni di lavoro. In virtù dell’esistenza di un sistema di regolazione semaforica adattativo, con la priorità semaforica per i mezzi pubblici il ciclo semaforico può variare continuamente, mitigando anche i ritardi delle correnti di traffico veicolare. Se un semaforo interrompe il moto di un tram, di fatto ne raddoppia indicativamente il consumo tra due fermate. Il beneficio sui tempi è quasi scontato, ma comunque emerge dallo studio, che si concentra prevalentemente sull’aspetto del consumo energetico

Point-of-care screening for a current Hepatitis C virus infection: influence on uptake of a concomitant offer of HIV screening

Eliminating hepatitis C as a public health threat requires an improved understanding of how to increase testing uptake. We piloted point-of-care testing (POCT) for a current HCV infection in an inner-city Emergency Department (ED) and assessed the influence on uptake of offering concomitant screening for HIV. Over four months, all adults attending ED with minor injuries were first invited to complete an anonymous questionnaire then invited to test in alternating cycles offering HCV POCT or HCV+HIV POCT. Viral RNA was detected in finger-prick blood by GeneXpert. 814/859 (94.8%) questionnaires were returned and 324/814 (39.8%) tests were accepted, comprising 211 HCV tests and 113 HCV+HIV tests. Offering concomitant HIV screening reduced uptake after adjusting for age and previous HCV testing (odds ratio 0.51; 95% confidence interval [CI] 0.38–0.68; p < 0.001). HCV prevalence was 1/324 (0.31%; 95% CI 0.05–1.73); no participant tested positive for HIV. 167/297 (56.2%) POCT participants lived in the most deprived neighbourhoods in England. HCV RNA testing using finger-prick blood was technically feasible. Uptake was moderate and the offer of concomitant HIV screening showed a detrimental impact on acceptability in this low prevalence population. The findings should be confirmed in a variety of other community settings