E-Health systems are experiencing an impulse in these last years, when many medical agencies began to include digital solutions into their platforms. Electronic Health Records (EHRs) are one of the most important improvements, being in its most part a patient-oriented tool. To achieve a completely operational EHR platform, security and privacy problems have to be resolved, due to the importance of the data included within these records. But given all the different methods to address security and privacy, they still remain in most cases as an open issue. This paper studies existing and proposed solutions included in different scenarios, in order to offer an overview of the current state in EHR systems. Bibliographic material has been obtained mainly from MEDLINE and SCOPUS sources, and over 30 publications have been analyzed. Many EHR platforms are being developed, but most of them present weaknesses when they are opened to the public. These architectures gain significance when they cover all the requisites related to security and privacy.

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a b s t r a c tMulticristalline Silicon (mc-Si) is the preferred material for current terrestrial photovoltaic applications. However, the high density of defects present in mc-Si deteriorates the material properties, in particular the minority carrier diffusion length. For this reason, a large effort to characterize the mc-Si material is demanded, aiming to visualize the defective areas and to quantify the type of defects, density and its origin. In this work, several complementary light and electron probe techniques are used for the analysis of both mc-Si wafers and solar cells. These techniques comprise both fast and whole-area detection techniques such as Photoluminescence imaging, and highly spatially resolved time consuming techniques, such as light and electron beam induced current techniques and mRaman spectroscopy. These techniques were applied to the characterization of different mc-Si wafers for solar cells, e.g. ribbon wafers, cast mc-Si as well as quasi-monocrystalline material, upgraded metallurgical mc-Si wafers, and finished solar cells.

Mono‐cast Si growth is currently a very promising approach to optimize the cost per watt in the production of PV devices, simultaneously increasing the installed energy/m2 ratio. However, due to the novelty of this growth approach, the material properties have not yet been studied in detail. In this work, by combining PL imaging with electrical characterization techniques (LBIC and EBIC), both the large scale and the local properties of the wafers grown from mono‐cast Si ingots have been analyzed. PL imaging shows two kinds of defects, which were studied in detail by LBIC. Electrical active defects are found in areas corresponding to a unique large grain, assigned to sub‐GBs, decorated by impurities. These defects have strong charge trapping, with deleterious consequences for the device performance. The presence of those intra‐grain defects is also confirmed by EBIC maps, which allows comparing the electrical activity of both grain and sub‐grain boundaries (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

In the silicon ribbon on a sacricial template process silicon is deposited on both sides of a carbon ribbon, thus forming a Si/carbon/Si trilayer. The fast cooling of the ribbon in large temperature gradients generates stresses that are detrimental to both the electrical performance and the mechanical behaviour of the wafers. The assessment of the stresses is crucial for the setting-up of thermal treatments allowing for the stress relaxation of the wafers, prior to the cell fabrication. We present an analysis of the stress in the as-grown trilayer by a simulation of the thermomechanical behaviour of the cooling ribbon. Experimental measurements of the stress in as-grown and annealed trilayers are also presented. The results permit to establish the conditions for optimized growth and annealing.