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Infrared reflectography, i.e. the use of images taken with infrared light, is currently applied in the field of cultural heritage mainly for paintings analysis to reveal the presence of underdrawings or alterations. Its use in archaeology for deciphering faded signs (texts, images, tattoos, etc.) is a lot more limited and in most cases no or simple data analysis and elaboration is performed. Here we show that infrared reflectography taken by using a wide spectral response (wavelength range from 400 to 2200 nm) VIDICON image acquisition system together with adequate post-elaboration, taking advantage from advanced techniques for data analysis (wavelet decomposition) and image registration and fusion, is able to produce high-quality 'C&IR' images. Such images can be obtained in a relatively easy way using the same hardware configuration generally used for infrared reflectographic analysis of paintings. The application to a medieval capsella (a small wooden relics container) from Cimitile, Italy, has shown that these results are of great interest for archaeologists. [ABSTRACT FROM AUTHOR]

Natural cartilage remodels both in vivo and in vitro in response to mechanical forces and hence mechanical stimulation is believed to have a potential as a tool to modulate extra-cellular matrix synthesis in tissue-engineered cartilage. Fluid-induced shear is known to enhance chondrogenesis on animal cells. A well-defined hydrodynamic environment is required to study the biochemical response to shear of three-dimensional engineered cell systems. We have developed a perfused-column bioreactor in which the culture medium flows through chondrocyte-seeded porous scaffolds, together with a computational fluid-dynamic model of the flow through the constructs' microstructure. A preliminary experiment of human chondrocyte growth under static versus dynamic conditions is described. The median shear stress imposed on the cells in the bioreactor culture, as predicted by the CFD model, is 3 × 10−3 Pa (0.03 dyn/cm2) at a flow rate of 0.5 ml/min corresponding to an inlet fluid velocity of 44.2 μm/s. Providing a fluid-dynamic environment to the cells yielded significant differences in cell morphology and in construct structure. [ABSTRACT FROM AUTHOR]