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Since the Hellenistic period, preparatory drawings known as sinopiae were employed as guidelines for mosaicists in creating mosaics. The sinopiae served as the basis for style and content, facilitating the placement of colored tesserae in the supporting mortar. The technology of the mosaic and pigments used reflect the capacity of the mosaic workshop and its master. This work explores a polychrome sinopia that was found under a Byzantine mosaic of an Armenian Chapel in Jerusalem, by a multi-analytical characterization of mineralogical and chemical properties. The composition of the pigments in the black and red areas of the sinopia include carbon black and red ochre, respectively, utilized in the fresco technique. Since colored tesserae are placed in wet mortar, it can be deduced that mosaicists worked together with painters during the executionary steps. This has corresponding implications for historical and artistic specializations at mosaic workshops, with deeper understanding of mosaic production processes. This research also highlights the importance of studying sinopiae under floor mosaics, which is a source of information on the pigments, paintings techniques, and the people who executed the work, all embedded in mortar which is well protected below the stone tesserae.

Analyzing, developing and exploiting results obtained by Laplace in 1785 on the Fourier-series expansion of the function (1−2αcosθ+α2)−s, we obtain a family of new expansions and generating functions for the Chebyshev polynomials. A relation between the generating functions of the Chebyshev polynomials Tn and the Gegenbauer polynomials Cn(2) is given.

Since the discovery of graphene, there has been a wide range of the literature dealing with its versatile structure and easy binding of biomolecules as well as its large loading capacity. In the emerging field of immunotherapy, graphene and its derivatives have potential uses as drug delivery platforms directly into tumour sites or as adjuvants in cancer vaccines, as they are internalized by monocytes which in turn may activate adaptive anti-tumoral immune responses. In this study, we expose cells of the innate immune system and a human acute monocytic leukemia cell line (THP-1) to low doses of small-sized GO nanosheets functionalized with bovine serum albumin (BSA) and fluorescein isothiocyanate (FITC), to study their acute response after internalization. We show by flow cytometry, uptake in cells of GO-BSA-FITC reaches 80% and cell viability and ROS production are both unaffected by exposure to nanoparticles. On the contrary, GO-BSA nanosheets seem to have an inhibitory effect on ROS production, probably due to their antioxidant properties. We also provided results on chemotaxis of macrophages derived from peripheral blood monocytes treated with GO-BSA. In conclusion, we showed the size of nanosheets, the concentration used and the degree of functionalization were important factors for biocompatibility of GO in immune cells. Its low cytotoxicity and high adaptability to the cells of the innate immune system make it a good candidate for deployment in immunotherapy, in particular for delivering protein antigens to monocytes which activate adaptive immunity.