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AFM was used to collect the whole force-deformation cell curves. They provide both the elasticity and adhesion behavior of mouse primary cardiac fibroblasts. To confirm the hypothesis that a link exists between the membrane receptors and the cytoskeletal filaments causing therefore changing in both elasticity and adhesion behavior, actin-destabilizing Cytochalsin D was administrated to the fibroblasts. From immunofluorescence observation and AFM loading/unloading curves, cytoskeletal reorganization as well as a change in the elasticity and adhesion was indeed observed. Elasticity of control fibroblasts is three times higher than that for fibroblasts treated with 0.5 μM Cytochalasin. Moreover, AFM loading-unloading curves clearly show the different mechanical behavior of the two different cells analyzed: (i) for control cells the AFM cantilever rises during the dwell time while cells with Cytochalasin fail to show such an active resistance; (ii) the maximum force to deform control cells is quite higher and as far as adhesion is concern (iii) the maximum separation force, detachment area and the detachment process time are much larger for control compared to the Cytochalasin treated cells. Therefore, alterations in the cytoskeleton suggest that a link must exist between the membrane receptors and the cytoskeletal filaments beneath the cellular surface and inhibition of actin polymerization has effects on the whole cell mechanical behavior as well as adhesion.

Research demonstrates that in the alumina matrix, prepared by using fine and coarse molybdenum particles, the toughness is directly related to the amount of molybdenum metal and the bridging stress is higher with coarse particles. Data suggest that the best microstructure is achieved when the metal particle size is more than 5 micrometer.

Byline: E. Luccini, S. Meriani, O. Sbaizero Ceria zirconia precursors were obtained by applying the urea hydrolysis method to Zr-oxychloride and Ce-nitrate solutions. Dewatering-dying procedures, such as freeze drying (FD) and acetone-toluene-acetone (ATA), were compared with the usual thermal method to assess their suitability for yielding fine, aggregate-free powders for the preparation of ceria-zirconia sinters. The characteristics of the powders before and after calcinations are discussed. The advantage of the ATA method is based on the fact that the formation of hard agglomerates is avoided, high specific surface is achieved and the tetragonal form was the only phase crystallizing on calcination of the chemical precursor.

Byline: S. Maschio, O. Sbaizero, S. Meriani Sinter-reactive powders of α-alumina have been prepared effectively by the decomposition of aluminium basic carbonates. In this work we have studied the urea CO(NH.SUB.2).SUB.2 homogeneous hydrolysis method, applied to alum solutions, KAl(SO.SUB.4).SUB.2 * 12H.SUB.20, using various urea and alum ratios, to precipitate aluminium basic carbonates. The thermal decomposition of the aluminium precipitates, produces fine alumina powders that are suitable for ceramic purposes.

Byline: S. Maschio, O. Sbaizero, S. Meriani In this investigation a series of Al.SUB.2O.SUB.3-ZrO.SUB.2, composites materials were prepared using unstabilised ZrO.SUB.2 or different amount of either Y.SUB.2O.SUB.3 or CeO.SUB.2 for stabilising the ZrO.SUB.2 in its metastable tetragonal form. The mechanical properties (hardness, bend strength and toughness) were measured and the influence of the different micro structure obtained as well as the role of phase transformation and micro cracks has been assessed.