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The paper presents the cases of tree children with clavicular swelling and a different final diagnosis that offered the opportunity to discuss the key points for the differential diagnosis of clavicular swelling and to draw a rational diagnostic work-up underlining the decisive role of MRI. Although several causes (in order: Chronic Recurrent Multifocal Osteomyelitis, Ewing sarcoma, Tietze syndrome) of clavicular swelling are proposed, it is essential to highlight that main causes are represented by neoplastic and inflammatory causes. However, even if clinical and anamnestic assessment are suitable to disentangle from diagnostic incertitude, imaging is often useful to obtain a diagnosis, before (or even without) biopsy. It is anyway mandatory to rule out neoplasia in all non-traumatic clavicular swelling.

The possibility of ultimately control the power deposition represents the way towards a wide spread adoption of hyperthermia in the clinic. The end goal is represented by the possibility of uniformly shaping the temperature over the target area while keeping it arbitrarily bounded elsewhere. In this respect, an innovative SAR-based optimization strategy, the so called Focusing via Constrained power Optimization (FOCO), has been proposed and recently tested in the clinic. Thanks to its huge versatility (as well as several advantages), different derivations of FOCO were developed addressing different clinical needs. In this communication we aim at review some of these derivations under a common framework.

Total Variation and Compressive Sensing (TV-CS) techniques represent a very attractive approach to inverse scattering problems. In fact, if the unknown is piecewise constant and so has a sparse gradient, TV-CS approaches allow us to achieve optimal reconstructions, reducing considerably the number of measurements and enforcing the sparsity on the gradient of the sought unknowns. In this paper, we introduce two different techniques based on TV-CS that exploit in a different manner the concept of gradient in order to improve the solution of the inverse scattering problems obtained by TV-CS approach. Numerical examples are addressed to show the effectiveness of the method.

In this communication, a new method for quantitative microwave imaging in biomedical applications is presented. This approach is based on the paradigm of 'virtual experiments' and on a regularization technique, which exploits projection onto a wavelet basis expansion. The basic steps of the method are presented and a preliminary example with two-dimensional simulated data is given, in order to demonstrate the potential of the method.

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La produzione di energia da gradienti salini si sta affermando come una valida alternativa alle tradizionali fonti di energia rinnovabili. In particolare l’elettrodialisi inversa (RED) è di certo tra le tecnologie più promettenti per effettuare la conversione di gradienti salini in energia utile. Un recente sviluppo è l’utilizzo del processo RED a ciclo chiuso con soluzioni saline artificiali, nel quale le soluzioni in uscita dall’unità RED vengono rigenerate all’interno di un’unità di rigenerazione termica, che ripristina il gradiente salino iniziale. L’utilizzo del sistema a ciclo chiuso premette dunque di convertire calore a bassa temperatura (e.g. calore di scarto a T

Reverse electrodialysis is a novel technology that exploits a salinity gradient to generate electrical energy. The salinity gradient can be available from natural waters such as seawater and river water or they can be artificially generated and used within closed-loop applications. This last option has been recently investigated leading to the development of the RED heat engine concept. In this case, the deployed salinity gradient exiting the RED unit is regenerated in a thermally-driven unit using low-temperature heat, thus being able to convert heat to power within an integrated system. Among the different regeneration alternatives, the use of thermolytic salts has been presented as a promising option, due to the possible use of very-low grade heat (40-60°C) to regenerate the solutions by means of degradation/stripping/re-absorption processes. In the present work, different regeneration strategies for ammonium bi-carbonate aqueous solutions have been investigated by means of process simulation (Aspen Plus) and experimental tests. Simulations have been performed looking at two different regeneration methods: i) stripping with air and ii) distillation (in practice, also a stripping process, but with vapour). A sensitivity analysis has been performed to study the effect of different operating variables (streams’ temperature, pressure, flow rate, inlet concentration) on the regeneration performance. The experimental campaign has been carried out mainly on the air stripping concept, which did turn to be the most promising within the expected range of operating conditions. Experiments were also aimed at identifying the main dependences (e.g. the effect of different packing materials and operating conditions on the performance indicators), technological limitations and relevant solutions. Eventually, a comparison between experimental information and model predictions has been performed in order to highlight the main discrepancies and validate model prediction capabilities.

Mg and MgCO3 are among the 20 EU critical raw materials. Interestingly, Mg can be found at very high concentration in brines generated as waste stream from salt works. Literature works have demonstrated the feasibility of Mg extraction from brines [1–3] by reactive precipitation, for the production of Mg(OH)2. Here we present an overview of the experimental campaigns carried out using exhausted brine from real salt works (Italy) to produce Mg(OH)2 with high purity and conversion. Lab – and pilot-scale batch and semi-continuous CSTR crystallisers were developed and tested, eventually leading to a continuous process by a quasi-PFR pilot reactor. Different alkaline solutions have been adopted in order to analyse their influence on the process, looking in particular at the product purity (affected by possible by-products co-precipitation) but also at the economic profitability. A late development focused on the development of a membrane crystalliser reactor using ionic exchange membranes (CrIEM) [4]. In the CrIEM the precipitation reaction occurs avoiding the direct contact between feed brine and alkaline solution, thus allowing in principle the use of any alkaline species, minimising the risk of by-products co-precipitation. In preliminary tests 99.5 % pure Mg(OH)2 was produced using cheap reactant, opening room for the development of a novel and economically profitable process

A novel idea for the conversion of low-temperature heat into electricity is based on the generation of electricity from salinity gradients using a Reverse Electrodialysis (RED) device in a closed-loop system. In this concept a limited amount of artificial saline solutions can be used as the working fluids in a closed-loop. The solutions exiting from the RED unit are then regenerated, in order to restore the original salinity gradient, by means of a separation step, which uses low-temperature heat (40-100°C) as its energy source. A theoretical analysis of potentials of this technology is illustrated in the present work.

An efficient inverse scattering strategy is proposed to achieve dielectric characterization of buried objects in lossy soils. The approach takes advantage of Virtual Experiments and Compressive Sensing to obtain quantitative reconstructions of nonweak targets which are nonsparse in the pixel representation basis, commonly adopted in microwave imaging. In addition, an original strategy is adopted to overcome the relevant information lack arising when data are gathered under aspect-limited configurations, such as in ground penetrating radar (GPR) surveys. The proposed strategy significantly outperforms the results achievable with the "state of the art" standard approaches since it allows to achieve nearly optimal reconstructions within a linear framework and without increasing the overall computational burden. Numerical examples with simulated data are given to show the feasibility of the proposed strategy.

In this communication, we discuss the potential and the perspectives of a new and effective framework to tackle the solution of inverse scattering problems. Starting from the statement that scattering phenomena can be recombined in many different ways (due to the linearity of Maxwell equations), it is possible to design suitable experiments where peculiar properties of the field or of the contrast source can be pursued. These virtual experiments, synthetically built by properly processing the available data, provide a convenient framework to recast the inverse problem, wherein the enforced properties can be exploited throughout the solution procedure. Accordingly, this concept is a powerful tool to derive new inversion approaches capable to handle as well as to overcome some of the typical difficulties and limitations in the solution of inverse scattering problems.