6 research outputs found
Are ant assemblages of Brazilian veredas characterised by location or habitat type?
Wetland areas in the Brazilian Cerrado, known as âveredasâ, represent ecosystems formed on sandy soils with high concentrations of peat, and are responsible for the recharge of aquiferous reservoirs. They are currently under threat by various human activities, most notably the clearing of vegetation for Eucalyptus plantations. Despite their ecological importance and high conservation value, little is known about the actual effects of human disturbance on the animal community. To assess how habitat within different veredas, and plantations surrounding them affect ant assemblages, we selected four independent vereda locations, two being impacted by Eucalyptus monoculture (one younger and one mature plantation) and two controls, where the wetland was surrounded by cerrado vegetation. Ant sampling was conducted in May 2010 (dry season) using three complementary methods, namely baits, pitfall traps, and hand collection, in the wetland and in the surrounding habitats. A total of 7,575 ants were sampled, belonging to seven subfamilies, 32 genera and 124 species.Ant species richness and abundance did not differ between vereda locations, but did between the habitats. When impacted by the monoculture, ant species richness and abundance decreased in wetlands, but were less affected in the cerrado habitat. Ant species composition differed between the three habitats and between vereda locations. Eucalyptus plantations had an ant species composition defined by high dominance of Pheidole sp. and Solenopsis invicta, while natural habitats were defined by Camponotus and Crematogaster species. Atta sexdens was strictly confined to native habitats of non-impacted âveredasâ. Eucalyptus monocultures require high quantities of water in the early stages, which may have caused a decrease in groundwater level in the wetland, allowing hypogeic ants such as Labidus praedator to colonise this habitat
Nota técnica: avaliação ultrassonogråfica de aneurismas da aorta tratados com endopróteses
Spontaneous dissection of the celiac trunk: report of three cases and review of the literature
Correção endovascular do aneurisma da aorta abdominal: anĂĄlise dos resultados de Ășnico centro
OBJETIVO: Avaliar os resultados clĂnicos imediatos e em mĂ©dio prazo do tratamento endovascular em pacientes portadores de aneurisma da aorta abdominal em um centro de referĂȘncia para doenças cardiovasculares. MATERIAIS E MĂTODOS: Estudo retrospectivo de uma sĂ©rie de pacientes submetidos a tratamento endovascular de aneurisma da aorta abdominal, no perĂodo de janeiro de 2009 a julho de 2010. Foram avaliados as caracterĂsticas demogrĂĄficas, o sucesso tĂ©cnico, o sucesso terapĂȘutico, a morbimortalidade, as complicaçÔes e a taxa de reintervençÔes perioperatĂłrias imediatos, e apĂłs um ano de acompanhamento. RESULTADOS: Foram analisados 102 pacientes consecutivos com idade mĂ©dia de 72 ± 9 anos, sendo 79% deles do sexo masculino. Houve sucesso tĂ©cnico em 97,1% e ĂȘxito terapĂȘutico em 81% dos casos. A mortalidade perioperatĂłria foi de 0,9% e a anual, de 7,8%. Foram necessĂĄrias reintervençÔes em 18,8% dos pacientes durante o seguimento. CONCLUSĂO: Em nosso estudo, os resultados obtidos justificam a realização desse procedimento nos pacientes com anatomia adequada