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International audience; Realistic breast phantoms are often required for supporting the development of microwave and mm-wave imaging systems for breast cancer detection. A number of phantoms have been proposed in the literature, but they are often realized using non-common or toxic materials, and characterized only for the microwave regime. Recently, mm-waves have been also proposed for screening purposes, especially for breast with a high fat content, to provide the resolution vital to detect early-stage cancer masses. Consequently, we proposed several recipes that can be used to create tissue-mimicking materials able to reflect the dielectric properties of different human breast tissues, from fat to neoplastic tissues. In this paper, we present new recipes specifically conceived to mimic up to 50 GHz the dielectric properties of very fat tissues, difficult to achieve otherwise. The involved materials are deionized water, sunflower oil, waste-oil hardener, and two different surfactants (lecithin and Polysorbate 80), all very cheap, easy-to-manage, not-toxic and common materials.

In modern ultrasound imaging devices, two-dimensional probes and electronic scanning allow volumetric imaging of anatomical structures. When dealing with the design of such complex 3-D ultrasound (US) systems, as the number of transducers and channels dramatically increases, new challenges concerning the integration of electronics and the implementation of smart micro-beamforming strategies arise. Hence, the possibility to predict the behavior of the whole system is mandatory. In this paper, we propose and describe an advanced simulation tool for ultrasound system modeling and simulation, which conjugates the US propagation and scattering, signal transduction, electronic signal conditioning, and beamforming in a single environment. In particular, we present the architecture and model of an existing 16-channel integrated receiver, which includes an amplification and micro-beamforming stage, and validate it by comparison with circuit simulations. The developed model is then used in conjunction with the transducer and US field models to perform a system simulation, aimed at estimating the performance of an example 3-D US imaging system that uses a capacitive micromachined ultrasonic transducer (CMUT) 2-D phased-array coupled to the modeled reception front-end. Results of point spread function (PSF) calculations, as well as synthetic imaging of a virtual phantom, show that this tool is actually able to model the complete US image reconstruction process, and that it could be used to quickly provide valuable system-level feedback for an optimized tuning of electronic design parameters.

Il presente lavoro offre un contributo metodologico alla progettazione concettuale di sedili ferroviari al fine del miglioramento della qualità percepita dall’utente finale. L’impiego combinato di idonei strumenti CAD, di metodi statistici di sperimentazione e della Realtà Virtuale, infatti, consente di dare forma alle idee per selezionarle e valutarle sperimentalmente. Il ciclo di progettazione parte dalla proposta di stile del designer e dall’identificazione delle esigenze dell’utente; prosegue con la modellazione di assieme nel rispetto dei vincoli normativi e la generazione di architetture alternative di prototipi virtuali di sedili ferroviari; termina, infine, con la valutazione, in ambiente di Realtà Virtuale, effettuata da potenziali utenti del concept di sedile ferroviario di maggiore qualità. Questa procedura offre al progettista una verifica realistica ed attendibile dei risultati ottenuti, permettendo di coinvolgere l’utente in tutte le fasi di sviluppo del prodotto. Nel lavoro viene presentato un caso studio relativo ad un treno regionale, sviluppato presso il Laboratorio di Realtà Virtuale del Centro di Competenza Trasporti della Regione Campania.

Angiogenesis in the failing heart is stimulated beta-1 AR blockade and cardiac beta-2 AR overexpression.

While glucocorticoids (GCs) are known to be present in the zebrafish embryo, little is known about their physiological roles at this stage. We hypothesised that GCs play key roles in stress response, hatching and swim activity during early development. To test this, whole embryo cortisol (WEC) and corticosteroid-related genes were measured in embryos from 6 to 120 h post fertilisation (hpf) by enzyme linked immunosorbent assay (ELISA) and quantitative real-time polymerase chain reaction (qRT-PCR). Stress response was assessed by change in WEC following stirring, hypoxia or brief electrical impulses applied to the bathing water. The impact of pharmacological and molecular GC manipulation on the stress response, spontaneous hatching and swim activity at different stages of development was also assessed. WEC levels demonstrated a biphasic pattern during development with a decrease from 0 to 36 hpf followed by a progressive increase towards 120 hpf. This was accompanied by a significant and sustained increase in the expression of genes encoding cyp11b1 (GC biosynthesis), hsd11b2 (GC metabolism) and gr (GC receptor) from 48 to 120 hpf. Metyrapone (Met), an inhibitor of 11β-hydroxylase (encoded by cyp11b1), and cyp11b1 morpholino (Mo) knockdown significantly reduced basal and stress-induced WEC levels at 72 and 120 hpf but not at 24 hpf. Spontaneous hatching and swim activity were significantly affected by manipulation of GC action from approximately 48 hpf onwards. We have identified a number of key roles of GCs in zebrafish embryos contributing to adaptive physiological responses under adverse conditions. The ability to alter GC action in the zebrafish embryo also highlights its potential value for GC research.

This work concerns the usability assessment of two control devices for a wheelchair-mounted robot manipulator aimed at assisting physical disabled people. The assessment of the usability is a crucial issue for the design of such products, since they communicate with their users not only through their shape, but especially through their control interfaces.In a first phase, the study focuses on defining a synthetic usability index on the basis of the methodologies currently in use. In a second phase, some experiments in Virtual Reality (VR) have been carried out.The use of VR technologies for the collection of the experimental data has been fundamental in terms of safety, costs and repeatability of the tests. Another important result has been the reduction of the sources of noise, thanks to preliminary simulations in VR and non-invasive questionnaires and interviews for capturing the subjective perceptions of users.Finally, it is worth noticing that the developed model may show its validity also in evaluating the usability of other products. Indeed, it provides a basis for a more extensive use of VR experiments for evaluating different design solutions in terms of global usability requirements.