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The steps of the morphological relapse occurring during gluten-challenge in coeliac children were for the first time investigated by scanning electron microscopy and compared with the morphological changes observed in untreated and treated coeliac patients, in pathological and normal controls. Some peculiar morphological changes, not reported up to now, were observed in treated and relapsed coeliac patients. No relationship was found among the degrees of mucosal atrophy observed by SEM and the duration of the challenge performed by an uncontrolled ingestion of gluten.

In any of the modern 4/spl pi/ particle detector array improvements of the measured parameters have been envisaged. Pulse shape discrimination (PSD) is an efficient electronic tool which can be applied to a single detector to achieve atomic number Z separation of the particles comparable to the /spl Delta/E - E telescopes. In the present study, a simple PSD device based on commercially available modules has been discussed with the motivation of future improvement in CHIMERA detector system without sacrificing time resolution in time of flight (TOF) measurement. In beam studies of PSD have been carried out following the ejected particles from /sup 19/F + /sup 12/C reaction at tandem energies with 2 large area - 300 /spl mu/m - silicon detectors of CHIMERA multi-detector. Front-side and rear-side entry of the detected ions were explored. Performance of the PSD set up has been discussed.

The capability of digital pulse shape technique to acquire data from CHIMERA detection cells (Si-CsI(Tl) telescopes) has been evidenced in our previous works. /spl Delta/E-E scatter plots to obtain charge identification for the detected reaction products and fast-slow scatter plots from the CsI(Tl) light pulses for light charged product identification have been carefully reconstructed. We have now applied this technique to the charge discrimination of the products which stop in the silicon detectors, by using large area totally depleted CHIMERA silicon detectors (300 /spl mu/m thick, 5/spl times/5 cm/sup 2/ area) in reverse mount. In preliminary tests full charge identification for the reaction products up to Z=11 have been obtained for products both crossing the silicon detector (/spl Delta/E-E technique) and stopping in it, using a 21.1 MeV/u /sup 20/Ne beam at the LNS superconducting cyclotron in Catania. The quality of the obtained results clearly indicates that the digital signal processing approach is able to give excellent results in this application, too.