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71.
Lorenzo Natalucci Pietro Ubertini Angela Bazzano Ezio Caroli Memmo Federici Egidio Quadrini Roberto Vittori 《Wireless Personal Communications》2009,51(4):725-737
Medical imaging applications using X- and gamma-rays have reached outstanding levels of complexity and performance, thanks to technology achievements in the fields of radiography, tomography and high resolution synchrotron devices. The operability of the related instrumentation resides in the availability of highly qualified specialists, as well as of medical doctors for diagnoses and treatment. This is a problem for personnel working in difficult ambient conditions as can be found in remote sites like Arctica, Antarctica and under-populated, desolated or mountainous regions on Earth. Astronauts, during long permanence at the Space Station or on future mission to Mars are potentially subject to risks such as traumas, fractures or diseases which would require semi-automated, easy-to-handle application of X-ray radiographic devices. For this purpose, the possible use of imaging instrumentation based on solid state detectors is discussed with special regard to CdZnTe pixel devices, now available with sub-mm resolution. The use of these semiconductor detectors will also allow to perform image diagnostics at much lower doses compared to the current plate-based radiographic techniques. 相似文献
72.
73.
Gina Rosalinda De Nicola Manuela Bagatta Eleonora Pagnotta Donato Angelino Lorenzo Gennari Paolino Ninfali Patrick Rollin Renato Iori 《Food chemistry》2013
The consumption of brassica sprouts as raw vegetables provides a fair amount of glucosinolates (GLs) and active plant myrosinase, which enables the breakdown of GLs into health-promoting isothiocyanates (ITCs). This study reports the determination of the main constituents related to human health found in edible sprouts of two Brassica oleracea varieties, broccoli and Tuscan black kale, and two Raphanus sativus varieties, Daikon and Sango. Radish sprouts exhibited the highest ability to produce ITCs, with Daikon showing the greatest level of conversion of GLs into bioactive ITCs (96.5%), followed by Sango (90.0%). Tuscan black kale gave a value of 68.5%, whereas broccoli displayed the lowest with 18.7%. ITCs were not the exclusive GL breakdown products in the two B. oleracea varieties, since nitriles were also produced, thus accounting for the lower conversion observed. Measuring the release of plant ITCs is a valuable tool in predicting the potential level of exposure to these bioactive compounds after the consumption of raw brassica sprouts. 相似文献
74.
75.
Mauro Epifani Marco Alvisi Luciana Mirenghi Gabriella Leo Pietro Siciliano Lorenzo Vasanelli 《Journal of the American Ceramic Society》2001,84(1):48-54
A chloride-based inorganic sol–gel route was used for preparing pure and metal (osmium, nickel, palladium, platinum)-doped SnO2 sol. SnCl4 was first reacted with propanol, then the resulting compound was hydrolyzed and subsequently mixed with solutions of the metal dopants. The obtained sols were used for depositing thin films by spin coating or for preparing powders by solvent evaporation at 110°C. FTIR spectroscopy and thermal analysis of the powders revealed that chlorine still bound to tin stabilized the sol against gelation by hindering the condensation reactions. Film characterizations showed that platinum and palladium, unlike nickel and osmium, were likely to form nanoparticles in the SnO2 lattice. This result was discussed with regard to the different ways that platinum and palladium, on one hand, and nickel and osmium, on the other, modified the growth of SnO2 grains and the film roughness and morphology. Dopants that formed nanoparticles (platinum, palladium) resulted in the roughest film, while dopants that did not form particles (nickel, osmium) resulted in SnO2 grain size very close to that of pure SnO2 . 相似文献
76.
Daniele Viciani Lorella Dell’Olmo Antonio Gabellini Daniela Gigante Lorenzo Lastrucci 《Landscape Research》2018,43(7):952-964
Widespread trends of abandonment have strongly affected Mediterranean mountains after the Second World War, triggering spontaneous recolonisation of forests. A diachronic analysis of the landscape in a Natura 2000 site (Tuscany, Italy) was carried out using digital aerial photographs (1954, 2013) and a GIS-based methodology, focusing on territories above 1300 m a.s.l. The detected variations of total areas, patch shape, patch dimensions and selected metrics showed a notable shift of the vegetation towards woody types and a drastic reduction of open grasslands, some with high conservation value, accompanied by a strong increase in patch number, surface and edge. A decrease of SDI and SEI diversity indices was also observed. Considering that fragmentation is one of the main causes threatening habitats and species, our results point out a clear necessity for a monitoring programme and suitable actions aimed at improving the status of biodiversity-rich montane grasslands. 相似文献
77.
Francesco Andreatta Luca Paussa Paolo Aldighieri Alex Lanzutti Dominik Raps Lorenzo Fedrizzi 《Progress in Organic Coatings》2010
Design, development and scale-up of environmentally friendly coatings are very important in order to replace chromate based coatings for aluminium alloys. Barrier properties, paint adhesion and possibly self-healing ability are relevant aspects for replacement of chromate-based pre-treatments. Sol–gel materials are candidates for use in protective coating applications, as it is possible to form highly adherent and chemically inert oxide films on metal substrates. 相似文献
78.
Vicente Pacheco Raul Cardoso-Gil Lorenzo Tepech-Carrillo Yuri Grin 《Corrosion Science》2011,(7):2368-2373
The corrosion of thermoelectric clathrates α- and β-Eu8Ga16−xGe30+x is studied under static air (DSC/TG) up to 650 °C. Oxidation product layers with thicknesses of 10.5 μm (α-Eu8Ga16−xGe30+x) and 4.5 μm (β-Eu8Ga16−xGe30+x) are formed. The oxidation begins at 360 and 380 °C, respectively. XRD pattern of the β-Eu8Ga16−xGe30+x oxidized layer shows Ge and four Eu2O3 reflections; while α-Eu8Ga16−xGe30+x data (sample crushed and grinded) shows α-Eu8Ga16−xGe30+x reflections (majority phase), two EuGa2±xGe4?x strongest reflections and Ge (minority phases). These results indicate the amount of oxides is very small or they are amorphous. High temperature powder XRD measurements on α-Eu8Ga16−xGe30+x under air confirm the oxidation onset temperature determined in DSC studies. 相似文献
79.
Delli Priscoli Francesco Di Giorgio Alessandro Lisi Federico Monaco Salvatore Pietrabissa Antonio Celsi Lorenzo Ricciardi Suraci Vincenzo 《International Journal of Control, Automation and Systems》2017,15(2):892-904
International Journal of Control, Automation and Systems - In the framework of the Future Internet, the aim of the Quality of Experience (QoE) Control functionalities is to track the personalized... 相似文献
80.
We discuss how vocal disorders can be post-corrected via a simple nonlinear noise reduction scheme. This work is motivated by the need of a better understanding of voice dysfunctions. This would entail a 2-fold advantage for affected patients: Physicians can perform better surgical interventions and on the other hand researchers can try to build up devices that can help to improve voice quality, i.e. in a phone conversation, avoiding any surgical treatment. As a first step, a proper signal classification is performed, through the idea of geometric signal separation in a feature space. Then through the analysis of the different regions populated by the samples coming from healthy people and from patients affected by T1A glottis cancer, one is able to understand which kind of interventions are necessary in order to correct the illness, i.e. to move the corresponding feature vector from the sick region to the healthy one. We discuss such a filter and show its performance. 相似文献