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Introduction: Adipose tissue represents an abundant source of mesenchymal stem-like cells. Adipose-derived stem cell progeny have been investigated and used in regenerative medicine for decades. In the last few years, they have been used to “enrich” lipoaspirates in fat grafting techniques, in an attempt to boost the regenerative potential of adipose tissue when used as autologous “filler”. Materials and Methods: 50 adipose tissue samples from lipoaspirates and subcutaneous breast tissue biopsies were used to generate adipose floating spheroid cell (ASphC) lines. ASphC were characterized for the expression of putative mesenchymal stem cell markers and used in vitro to test their multilineage potential. Furthermore, ASphCs were seeded on dermal regeneration template (Integra®) and implanted into the T8 vertebral laminectomy site of immunocompromised mice. Results: Here, we show that the majority of ASphCs are in a quiescent state and express the putative surface stem cell marker CD271. Unlike CD271- cells, CD271+ ASphCs grew indefinitely in vitro as undifferentiated spheres in serum-free medium, maintaining their multilineage differentiation potential ability. Importantly, p107, a functional adipose stem cell marker, is strictly expressed in ASphCs and barely present in their differentiated mesenchymal lineages. These sphere cells display an enhanced ability in vitro to differentiate into distinctive end-stage cell types, such as osteoblasts, chondrocytes and adipocytes. Gene expression profiling analysis indicated that ASphCs are endowed with stem cell potential that is gradually lost during specific differentiation. Finally, ASphCs facilitate bone inter body repair and regeneration after laminectomy. Conclusions: We conclude that ASphCs possess a pronounced in vivo activity to regenerate the bone injury. Overall, ASphCs represent a heterogeneous population of stem-like cells harbouring multilineage differential potential and representing a prospective promising tool in cell therapy and tissue engineering.

In this work, the electrical and structural properties of Ti/Al contacts on AlGaN/GaN heterostructures with a different crystalline quality were investigated. In particular, the sample with a lower defects density required a higher temperature (800 degrees C) to obtain Ohmic contacts, while the more defective sample showed Ohmic behaviour at lower annealing temperature (500 degrees C). The susceptibility to oxidation of the metal stack upon annealing has been monitored by chemical analyses. Moreover, the temperature dependence of the contact resistance of the Ti/Al annealed contacts revealed that the interface current transport mechanism depends on the material quality. These results were attributed to the presence of V-shaped defect close to the surface of the AlGaN barrier layer. A nanoscale electrical analysis demonstrated a preferential current conduction through these defects, which indeed plays a relevant role for the formation of the Ohmic contact.

Access to Earth Observation products remains difficult for end users in most domains. Although various search engines have been developed, they neither satisfy the needs of scientific communities for advanced search of EO products, nor do they use standardized vocabularies reusable from other organizations. To address this, we present the Prod-Trees platform, a semantically-enabled search engine for EO products enhanced with EO-netCDF, a new standard for accessing Earth Observation products.

The knowledge of the temperature behavior of Ohmic contacts is an important issue to understand the device operation. This work reports on an electrical characterization as a function of the temperature carried out on nickel suicide (Ni2Si) Ohmic contacts, used both for n-type and p-type implanted 4H-SiC layers. The temperature dependence of the specific contact resistance suggested that a thermionic field emission mechanism dominates the current transport for contacts on p-type material, whereas a current transport by tunneling is likely occurring for the contacts on n-type implanted SiC. Furthermore, from the temperature dependence of the electrical characteristics, the activation energies for Al and P dopants were determined, resulting of similar to 145 meV and similar to 35 meV, respectively. The thermal stability of the electrical parameters has been demonstrated upon a long-term (up to similar to 100 hours) cycling in the temperature range 200-400 degrees C.

Access to Earth Observation products remains difficult for end users in most domains. Although various search engines have been developed, they neither satisfy the needs of scientific communities for advanced search of EO products, nor do they use standardized vocabularies reusable from other organizations. To address this, we present the Prod-Trees platform, a semantically-enabled search engine for EO products enhanced with EO-netCDF, a new standard for accessing Earth Observation products. © Springer International Publishing Switzerland 2014.

Access to Earth Observation products remains difficult for end users in most domains. Although various search engines have been developed, they neither satisfy the needs of scientific communities for advanced search of EO products, nor they use standardized vocabularies reusable from other organizations. To address this, we present the Prod-Trees platform, a semantically-enabled search engine for EO products enhanced with EO-netCDF, a new standard for accessing Earth Observation products. © Springer International Publishing Switzerland 2014.

The electrical characteristics of Au/3C-SiC Schottky diodes were studied and related to crystal defects. A structural analysis performed by transmission electron microscopy (TEM), combined with a current mapping of the surface by conductive atomic force microscopy (C-A FM), indicated that stacking faults (SFs) are the conductive defects having the biggest influence on the electrical properties of the Schottky barrier on 3C-SiC. Further, C-AFM current mapping of the semiconductor surface also showed that an ultraviolet (UV) irradiation process enables the electrical passivation of the SFs, due to their preferential oxidation. From current-voltage (I-V) measurements in diodes of different area (different amount of defects) it was observed that, for the non-irradiated surface, no significant dependence of the Schottky barrier height (Phi(B)) on the contact area could be observed. On contrast, after the UV-irradiation, Phi(B) gradually increases with decreasing contact area, ultimately leading to a nearly ideal value of the barrier height for the smallest diodes. The results indicate that even after the passivation of SFs there are still some electrically active defects contributing to deleterious conduction, responsible for a worsening of the electrical properties of the diodes

Attraverso l'analisi di documentazione testuale e cartografica, è stata realizzata una ricostruzione dinamica degli eventi legati alla partecipazione dell'Italia all'invasione nazista della Russia. Il progetto è stato realizzato utilizzando la tecnologia GIS, che ha consentito di integrare dati storici e geografici fornendo una modalità innovativa per la visualizzazione e l'interrogazione dei dati. È stato possibile stratificare i dati raccolti in una serie di livelli informativi, ricreando e rileggendo gli eventi storici. Una volta completato lo sviluppo del GIS è stato realizzato un webGIS per la consultazione online dei risultati del progetto.

The GIIDA project aims to develop a digital infrastructure for the spatial information within CNR. It is foreseen to use semantic-oriented technologies to ease information modeling and connecting, according to international standards like the ISO/IEC 11179. Complex information management systems, like GIIDA, will take benefit from the use of terminological tools like thesauri that make available a reference lexicon for the indexing and retrieval of information. Within GIIDA the goal is to make available the EARTh thesaurus (Environmental Applications Reference Thesaurus), developed by the CNR-IIA-EKOLab. A web-based software, developed by the CNR-Water Research Institute (IRSA) was implemented to allow consultation and utilization of thesaurus through the web. This service is a useful tool to ensure interoperability between thesaurus and other systems of the indexing, with, the idea of cooperating to develop a comprehensive system of knowledge organization, that could be defined integrated, open, multi-functional and multilingual. Currently the system is available in multiple languages mode (Italian - English) and navigation can be done in the following ways: Alphabetical, Hierarchical and for Themes. A full search allows to find any term by searching for the whole term or a part of it and as well as allows to filter the results by themes. Within a collaborative initiative with the CNR-Institute of Applied Mathematics and Information Technology (IMATI) a SKOS (Simple Knowledge Organization System) version of EARTh was developed. This will ensure the possibility to support the use of the thesaurus within the framework of the Semantic Web in order to be used in decentralized metadata applications.

In 2006 we started a project for the reconstruction using GIS technology of the Italian Army operations in the Russia Campaign (1941-1943). The studied area covers 15 states with an extension of 102° in longitude and 28° in latitude. The project has two major goals: to identify the places linked to troops displacement, to major battles and to retreat phases; to identify the military cemeteries and the Prisoners-of-War camps to represent troops displacement and movements in a cartographic environment; to develop a unique tool for management and querying all the geographic information linked to the events. As a base level for the representation of data and cartography a Landsat 5TM mosaic, taken in summer 1984, has been used. Satellite images have been treated in order to enhance the land features, with particular regard to hydrography, road and railway network, and inhabited places. All these elements were essential in order to link the information extracted from the references to the territory. Collected data were extremely heterogeneous: the majority of information has been extracted from more than 150 books and the available maps, drawings and schemas, with a scale ranging from 1:100.000 to 1:300.000. Moreover 247 soviet maps, at different scale, ranging from 1:100.000, to 1:1.000.000, were downloaded, georeferenced and used as cartographic layer, to validate and integrate information coming from books and to identify relevant places. When missing in the sources, geographical coordinates have been provided to all elements. The GIS has been developed using open source software (QGIS); all the available information has been collected into different thematic layers. A 1943 geological map was compared to the satellite images and to cartography in order to analyse the events in the deployment area in relation to the land features. Names of cities, villages, rivers, etc. were written in several different ways, depending on sources and due to the different transcription from the original Russian or Ukrainian names. A "rollback" work was thus necessary in order to collect all the different versions, identify Cyrillic name and Romanize it according to the rules of the Working Group on Romanization Systems of the United Nations Group of Experts on Geographical Names (UNGEGN). More than 700 places have been stored into a database. Starting from this proper geographic base, vectorial layers were created. Actually, point layers have been generated from the geodatabase while line and polygon layers have been manually generated by digitalisation. Vectors were thematically clustered depending on the geographical or historical aspects: hydrography, relevant places, railroads, deployment of troops, prisoner-of-war camps, military retreats, etc. Starting from the GIS project, a WebGIS was developed and is accessible at http://webgis.iia.cnr.it/CampagnadiRussia/. The Russian Campaign WebGIS was implemented through MapServer for Windows - MS4W based on the Apache HTTP Server version 2.2.8 that ensures good data interoperability and flexible tools that can be customised to meet user needs. As a MapServer PHP/MapScript framework, p.mapper 3.2 version, was chosen.

In this paper the activities in the field of terminology and thesauri carried out by the Environmental Knowledge Organisation Laboratory of the Italian National Research Council will be presented. In 2000 EKOLab started the development of a thesaurus for the environment called EARTh (Environmental Applications Reference Thesaurus). The thesaurus is constantly updated following the growing request of updated terminology in relevant topics. At present it contains about 12.000 terms, in English and Italian. It is provided with hierarchical relations and classified according to a matrix system. In parallel with the development of EARTh, two separate projects were carried on and lead to the development of two thesauri, one on Remote Sensing and GIS and the other on the Snow/Ice environment. Each one of these thesauri contains about 3.500 terms. A 1.500 terms lexicon on pollution and climate changes has recently been created. The Thesauri are handled using SuperThes, a software developed within an International co-operation including CNR, UBA-Austria, UBA Germany and the TBHS company. The web interface is under development.

The growth rate of 4H-SiC epi layers has been increased up to 100 OEºm/h with the use of trichlorosilane instead of silane as silicon precursor. The epitaxial layers grown with this process have been characterized by electrical, optical and structural characterization methods. Schottky diodes, manufactured on the epitaxial layer grown with trichlorosilane at 1600 ¬?C, have higher yield and lower defect density in comparison to diodes realized on epilayers grown with the standard epitaxial process. ¬© (2009) Trans Tech Publications, Switzerland.

E' stato elaborato un Sistema Informativo Territoriale ricadente alla porzione del Parco Nazionale Gran Sasso e Monti della Laga delimitata dai confini amministrativi del Comune di Amatrice. Sono stati elaborati livelli vettoriali relativi alle componenti geologiche, geomorfologiche e ambientali. Successivamente sono stati aggiunti i livelli relativi all'ambiente costruito, alle risorse turistiche e escursionistiche. Una volta realizzato il GIS si è passati alla creazione di un webGIS realizzato con strumenti open source.

A large photocurrent increase in 4H-SiC interdigit Schottky UV detectors was observed in the presence of a thermally grown silicon oxide layer. In particular, internal quantum efficiency higher than unity indicated the presence of an internal gain strictly correlated with the presence of the superficial oxide on SiC. Moreover, a long recovery time, in the range of 10-19 s, was evaluated by fall-time photocurrent measurements due to the detrapping of charges in the oxide after the irradiation switching off. The photoresponse of the device was analytically described considering the lowering of the surface potential barrier due to charges trapped at the oxide/semiconductor interface.

Around 2.500 terms, coming from different sources, related to Earth sciences but environmentally relevant have been included in the EARTh thesaurus which is the result of a research project at CNR. Terms have been selected, checked, validated and then put into the thesaurus. The organization of environmental knowledge should rely on a referral grid for the analysis of reality, for the classification of concepts and for the explanation of their "more essential" meanings. Each concept has an intrinsic semantic complexity which emphasizes particular and contingent aspects. Solid conceptual foundations are essential for the management and the integration of conceptual and terminological heterogeneity of information systems. EARTh is based on a faceted structure. Its classification scheme was built utilizing a deductive-inductive approach and is based on the identification and adoption of a system of categories. The Thesaurus vertical structure is founded on categories; it is organized in a framework of different levels and classification knots, and it comprises hierarchical relationships. Terms have been arranged in a vertical structure acting as a tool that highlights the "primary meaning" of terms. The result is a semantic reference system, stable and partially independent from the context. Due to the rigidity of the vertical structure the planned model envisages the possibility of complementing the faceted structure with a system of themes crossing the vertical structure and forming a matrix system. Themes' function is to reassemble terms that in the vertical structure have been scattered under the more general referral concept. The traditional semantic relationships (associative, equivalence and hierarchical) has been enriched through an extended set of subrelationships. The enrichment and the logical clarification of the relationships, reinforce their potential utilization for navigating on a conceptual basis. The increase and the specification of the associative relationships will strengthen the capacity of the system to represent the interconnected feature of the conceptual area. Earth sciences terminology has historically posed some critical points, well-known from the first attempt to apply the Linnaues taxonomy of organisms to rocks, minerals and soils (E. Mendes da Costa). These criticalities are due to the effort to organize them in a strictly hierarchical scheme. Morover the Earth sciences include a great number of different topics: from paleontology to hydrogeology, from mineralogy to engineering geology; each of these applied disciplines has its own specific terminology and poses different problems in terms of conceptual organization. In EARTh the geological terms, as all the others, belong to three macrocategories: Entities, Attributes and Dynamic aspects; they have been distributed in different hierarchical branches under specific facets and node labels. In addition a system of related terms establishes a direct association between terms that are not hierarchically-based linked. The result is a network of interrelated concepts, complex in its structure but easy to browse avoiding unnecessary noise and without loosing the precision in the navigation. I.e. the term "coal" has been included both in the following path ENTITIES - MATERIAL ENTITIES - NON LIVING ENTITIES - ARTIFICIAL ENTITIES - , to indicate the coal as a material extracted, manufactured and used while the path for "coal (rocks)" is ENTITIES - MATERIAL ENTITIES - NON LIVING ENTITIES - NATURAL ENTITIES - to point out the meaning of the term "coal" as a sedimentary organic rock. The semantic duplicity of the term "coal" has been overcome applying two different parenthetic qualifiers to the terms in order to differentiate the artificial material and the rock, thus avoiding polyhierarchy.

In this work, we report on 4H-SiC vertical Schottky UV-photodiodes, with a novel "semitransparent" electrode, using self-aligned Ni2Si interdigit contacts, that allow operation in the pinch-off regime of the directly exposed optically active area. This improves short wavelength detector sensitivity with respect to conventional semitransparent Schottky UV detectors which use thin metal films. Computer simulations of the electric field distribution were used to optimise the device's front electrode Geometry, maximising the pinch-off surface effect. The detector dark current was about 200 pA at -50 V thanks to the high Schottky barrier of the Ni2Si on the 4H-SiC (1.66 eV). Under illumination with radiation at 254 nm, an increase of the current of more than two orders of magnitude is observed, resulting in 78% internal quantum efficiency. The vertical photodiodes showed an ultraviolet-visible rejection ratio of about 104 and a current responsivity factor of 1.8 higher than a conventional planar metal-semiconductor-metal interdigit structure.

High growth rate of 4H-SiC epitaxial layers can be reached with the introduction of HCl in the deposition chamber. The effect of the Cl/Si ratio on this epitaxial growth process has been studied by optical and electrical measurements. Optical microscopy shows an improvement of the surface morphology and luminescence measurements reveal a decrease of epitaxial layer defects with increasing the Cl/Si ratio in the range 0.05–2.0. The leakage current measured on the diodes realized on these wafers is reduced of an order of magnitude and DLTS measurements show a decrease of the EH6,7 level concentration in the same range of Cl/Si ratio. The value Cl/Si=2.0 allows to grow epitaxial layers with the lowest defect concentration.

The growth rate of 4H-SiC epi layers has been increased by a factor 19 (up to 112 µm/h) with respect to the standard process with the introduction of HCl in the deposition chamber. The epitaxial layers grown with the addition of HCl have been characterized by electrical, optical and structural characterization methods. An optimized process without the addition of HCl is reported for comparison. The Schottky diodes, manufactured on the epitaxial layer grown with the addition of HCl at 1600 °C, have electrical characteristics comparable with the standard epitaxial process with the advantage of an epitaxial growth rate three times higher.