Analytic and Gevrey Hypoellipticity for Perturbed Sums of Squares Operators

We prove a couple of results concerning pseudodifferential perturbations of differential operators being sums of squares of vector fields and satisfying H\"ormander's condition. The first is on the minimal Gevrey regularity: if a sum of squares with analytic coefficients is perturbed with a pseudodifferential operator of order strictly less than its subelliptic index it still has the Gevrey minimal regularity. We also prove a statement concerning real analytic hypoellipticity for the same type of pseudodifferential perturbations, provided the operator satisfies to some extra conditions (see Theorem 1.2 below) that ensure the analytic hypoellipticity

Mesotelioma pericardio in un cane

SUMMARY - This report describes thè anatomohistopatological, ultrastructural and immunohistochemical findings in a 7-year-old mongrel bitch affected with pericardial mesothelioma. The bitch during 8 month had clinical signs suggesting pericardial effusion. Histological examination of thè biopsy specimen revealed nests of suspected mesothelial neoplastic cells. Given its unfavourable prognosisi thè dog was euthanatìzed. At necropsy, thè parietal and visceral surface of thè pericardium were covered with irregular brown-yellow,velvety nodules and plaques, Neoplastic nodules and plaques were also present in thè pleura. Histologically, diffuse cuboidal epithelioid cells cove-l ring papìllary projections on a spindle celi fibrovascular core were found. The ultrastructural and immunohistochemical findings were characteristic of mesothelial cells

La Ciatostomiasi larvale nel cavallo – Aspetti anatomoistipatologici

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Effects of feeding raw or extruded linseed on the ruminal ecosystem of sheep

Polyunsaturated fatty acids affect bacterial and protozoal population, inducing important modifications in rumen metabolism. The aim of this study was to investigate the effect of linseed extrusion on in situ ruminal degradability and microbial number and distribution. Six ruminally fistulated sheep were divided in 3 groups and fed one of the following diets according to a replicated Latin square design: (a) control, based on mixed hay and maize grains; (b) as in (a) plus 130 g of grounded raw linseed; (c) as in (b) except that the linseed was extruded. Extrusion decreased linseed dry matter and fat degradabilities. There was a marked reduction of total protozoal population in sheep fed supplemented diets. No effects were observed between groups on bacterial concentration, hay dry matter and NDF in situ degradabilities