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51.
Alessandra Bianco Ilaria Cacciotti Mariangela Lombardi Laura Montanaro Edoardo Bemporad Marco Sebastiani 《Ceramics International》2010,36(1):313-322
Fluorine-substituted hydroxyapatites are considered promising materials for bone scaffolding. In this study a systematic investigation on F-half substituted hydroxyapatite (F-HAp, Ca10(PO4)6OHF) obtained by precipitation is reported. Results on composition analysis, thermal behaviour, and sinterability are presented for a comparison with the respective pure hydroxyapatite. Samples were characterised by electron microscopy, induced coupled plasma-atomic emission spectroscopy, thermal analysis, infrared spectroscopy, N2 adsorption measurements, X-ray diffraction and dilatometry. A semicrystalline F-substituted hydroxyapatite powder made up of needle-like nanoparticles was obtained. Notwithstanding that it was thermally stable up to 1300 °C, it was sintered at relatively low temperatures obtaining a very fine microstructure with a relevant nano-porosity, beneficial in view of cell adhesion and in-growth.Hardness, elastic modulus and toughness of produced samples were investigated by Vickers–Knoop microhardness testing. Significant improvements of the mechanical properties were observed for the F-substituted hydroxyapatite, in comparison with pure hydroxyapatite. 相似文献
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Marcella Mastromatteo Alessandra Danza Mariangela Guida Matteo Alessandro Del Nobile 《International Journal of Food Science & Technology》2012,47(10):2109-2116
In this work, the hydration process of durum wheat–based functional bread loaded with yellow pepper flour was optimised. In particular, the investigated vegetable flour and durum wheat semolina were mixed after they were separately hydrated. Three different amounts of water added to the yellow pepper flour were studied for assessing the effect of vegetable flour hydration level on the dough development and overall quality of bread. The bread formulation investigated in a previous work, based on 25% of yellow pepper and 2% of guar seed as structuring agent where the vegetable flour was directly added to the hydrated durum wheat semolina dough, was chosen as control sample. Results highlighted that dough samples with yellow pepper flour hydrated at highest water content showed a rheological behaviour similar to the durum wheat dough. Moreover, creep analysis showed that the sample added with no‐hydrated yellow pepper flour recorded the greatest resistance to deformation. Same results were obtained for the dough tensile and bread compression tests. The use of the hydrated yellow pepper flour also improved all sensorial attributes. 相似文献
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Daniela Erriquez Giovanni Perini Alessandra Ferlini 《International journal of molecular sciences》2013,14(10):19681-19704
ncRNAs are the most recently identified class of regulatory RNAs with vital functions in gene expression regulation and cell development. Among the variety of roles they play, their involvement in human diseases has opened new avenues of research towards the discovery and development of novel therapeutic approaches. Important data come from the field of hereditary muscle dystrophies, like Duchenne muscle dystrophy and Myotonic dystrophies, rare diseases affecting 1 in 7000–15,000 newborns and is characterized by severe to mild muscle weakness associated with cardiac involvement. Novel therapeutic approaches are now ongoing for these diseases, also based on splicing modulation. In this review we provide an overview about ncRNAs and their behavior in muscular dystrophy and explore their links with diagnosis, prognosis and treatments, highlighting the role of regulatory RNAs in these pathologies. 相似文献
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Adsorption tests were performed on two different exhausted oils to reduce their polluting and health hazard potential: a "water-insoluble oil", utilised for automotive engine lubrication, and an "emulsified" oil, used as coolant for metal-cutting tools. Dolomite, a low-cost recovery material, was used to prepare two effective adsorbents: (a) a mixed Ca and Mg oxide obtained by thermal decomposition of dolomite at 1800 degrees C, and (b) an activated material obtained by submitting this product to chemical treatment with HCl. Preliminary tests carried out with an excess of the former material showed that the insoluble oil was adsorbed with lower yield (Y = 0.40) than the soluble (emulsified) oil (Y = 0.60). The material activation with HCl remarkably improved the adsorption of soluble oil organic fraction (Y > 0.90), while only a little increase in the removal yield was observed for the insoluble oil (Y = 0.44). The results presented and discussed in this work pointed out that the products of dolomite calcination can successfully replace the conventional adsorbing materials in the removal of organic pollutants, with particular concern to exhausted soluble oils, which cannot usually be recycled, thus reducing the operational costs of their treatment. 相似文献
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It can be hypothesized that children inherit their parents' driving habits both through genetic disposition and model learning. A few studies have shown indeed that parents' and their children's traffic convictions and accidents correlate which, however, may be due to life style and other exposure factors. This study aimed at investigating the relationships between parents' and their children's self-reported driving behavior. The subjects were 174 parent-child pairs who independently completed a questionnaire. Driving behavior-driving style-was evaluated by means of Manchester driver behavior questionnaire (DBQ), while data about driving exposure, life style, accidents, and traffic tickets were also collected. A series of regression models indicated that parents' self-reported driving behavior explains their children's respective self-reported behavior, even when exposure and demographic and life-style factors are controlled. 相似文献
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Summary In this paper two uniqueness theorems for an anisotropic mixture of two linear elastic solids are established: The former concerns the mixed boundary-value problem, the latter the displacement problem. These theorems are proved for unbounded domains in the absence of artificial restrictions upon the behaviour of the unknown fields at infinity. A reciprocity theorem is also given. 相似文献