Els germans Petrides a Barcelona : dos trompistes bohemis al Teatre de la Santa Creu (1794-1798)

Aquest treball documenta l’estada a Barcelona, entre el 1794 i 1798, dels germans Joseph i Peter Petrides, trompistes nascuts a Praga. L’excepcional trajectòria d’ambdós a la capital catalana, com a membres de l’orquestra del Teatre de la Santa Creu i com a solistes destacats, il·lustra el desenvolupament de l’ofici de músic a la ciutat durant l’última dècada del segle XVIII.

Light and electron microscopy of Myxobolus sciades n. sp. (Myxozoa), a parasite of the gills of the Brazilian fish Sciades herzbergii (Block, 1794) (Teleostei: Ariidae)

A myxosporean parasite in the gill lamellae of the freshwater teleost fish, Sciades herzbergii (Ariidae) (Block, 1794), from the Poti River (Northeast of Brazil) was described by light and electron microscopy studies. Polysporic histozoic cyst-like plasmodia containing several life-cycle stages, including mature spores, were observed. The spores were pyriform and uninucleate, measuring 9.15 ± 0.39 μm (n = 50) long, 4.36 ± 0.23 μm (n = 25) wide and 2.61 ± 0.31 μm (n = 25) thick. Elongated pyriform polar capsules (PC) were of equal size (4.44 ± 0.41 μm long and 1.41 ± 0.42 μm in diameter) and each contained a polar filament with 9-10 coils obliquely arranged in relation to the axis of PC. The PC wall was composed of two layers of different electron densities. Histological analysis revealed the close contact of the cyst-like plasmodia with the basal portion of the epithelial gill layer, which exhibited some alterations in the capillary vessels. Based on the morphological and ultrastructural differences, the similarity of the spore features to those of the genus Myxobolus and the specificity of this host to previously described species, we describe a new species named Myxobolus sciades n. sp. in this study.

DESSINS ET CROQUIS de costumes pour les opéras représentés à Paris et à Versailles de 1739 à 1767.

Dessins de costumes pour l'Opéra (1739-1767)