The hydrogen storage properties of pure magnesium and magnesium ZK60 alloy containing 2.5 wt% of mischmetal (Mm) processed by Cold Rolling (CR) and Low Temperature Rolling (LTR) were investigated. Before CR and LTR processing, Equal Channel Angular Pressing (ECAP) was employed in the alloys as an initial processing step to refine their microstructures. Microstructure findings showed that the ECAP+LTR route is more effective than the others to generate grain refinement - a desirable aspect in hydrogen storage materials. SEM and TEM results in combination with XPS analysis revealed that the ZK60 + 2.5 wt. % Mm alloy after being processed by ECAP + LTR had more refined grains (with sizes < 1μm) and exhibited superior resistance to the formation of oxides and/or hydroxides when compared with the pure magnesium alloy. The refined microstructures of the ECAP+LTR samples combined with the presence of highly oriented grains along to the (002) plane and large amount of defects – which are features associated to the LTR route - such as cracks and voids, resulted in a fast activation kinetics than for the samples processed by ECAP + CR route.

RESUMO Com o objetivo de conhecer-se a freqüência sorológica antileptospírica em cães e sua correlação com roedores e fatores ambientais, na área territorial urbana de 32 km2 do Município de Botucatu, SP, colheram-se 1.000 amostras de sangue de cães, em 20 postos homogeneamente distribuídos. A prova diagnóstica utilizada foi a de soroaglutinação microscópica (SAM), com 24 sorovares de Leptospira spp. Das 1.000 amostras submetidas à prova, 17,9% foram reagentes. Os cães reagentes que tiveram contato com roedores (23,68%) mostraram-se significativos (p < 0,05) em relação aos reagentes que não tiveram contato (15,37%). Na correlação entre animais de residências ligadas (18,10%) ou não ligadas (13,63%) à rede pública de esgoto e a soropositividade, não se observou significância estatística (p > 0,05). Ocorreram reações para 20 sorovares, com maior importância para: castellonis (28,68%), autumnalis (19,12%), pyrogenes (17,65%), icterohaemorrhagiae (11,03%) e canicol (9,56%).

ABSTRACT The aim of this study was to ascertain the antileptospirosis serological frequency in dogs and its correlation with rodents and environmental factors in a 32 km2 urban area of Botucatu, SP, Brazil. One thousand blood samples were collected from dogs at 20 homogenously distributed stations. The microscopic serum agglutination diagnostic test (SAM) was used with 24 Leptospira spp. serovars. From the 1,000 samples tested, 17.9% were reactive. Reactive dogs who had contact with rodents (23.68%) were significant (p < 0.05) in relation to those without contact (15.37%). There was no statistical significance (p > 0.05) between seropositive animals from homes connected (18.10%) and not connected (13.63%) to the public sewage system. There were reactions to 20 serovars, the most important were: castellonis (28.68%), autumnalis (19.12%), pyrogenes (17.65%), icterohaemorrhagiae (11.03%), and canicola (9.56%).

Clinic-epidemiological data in canine infection by Hepatozoon canis were reported. Apatia, anorexia, prostaction, weight loss and muscle pain were the most-common clinical recognized signs. Blood smear was used as diagnosis method for the detection of H. canis gamonts in the neutrophils. Anaemia, leucocytosis, monocytosis and lymphopenia were observed in the haematological exams. Imidocarb dipropionate associated with tetracyclines and sulfamethoxasole-trimethoprim were used in therapy.

Propionibacterium acnes as immunostimulant in oral canine papillomatosis treatment in 16 animals was studied. Regression of the pappiloma started being observed after the second aplication, with complete resolution in all dogs after the sixth aplication. These results suggest the use of P. acnes as an alternative in oral canine papillomatosis therapy.