Tropical forest mammal assemblages are widely affected by the twin effects of habitat loss and habitat fragmentation. We evaluated the effects of forest patch metrics, habitat structure, age of patch isolation, and landscape metrics on the species richness, abundance and composition of small mammals at 23 forest fragments (ranging in size from 43 to 7,035 ha) in a highly deforested 3,609-km2 landscape of southwestern Brazilian Amazonia. Using pitfall traps and both terrestrial and arboreal traplines of Sherman, Tomahawk and snap traps, we captured a total of 844 individuals over 34,900 trap-nights representing 26 species and 20 genera of small-mammals, including 13 rodent and 13 marsupial species. We also consider the effects of distance from forest edges on species occupancy and abundance. Overall small mammal abundance, species richness and species composition were primarily affected by the quality of the open-habitat matrix of cattle pastures, rather than by patch metrics such as fragment size. Ultimately, small mammal community structure was determined by a combination of both landscape- and patch-scale variables. Knowledge of the anthropogenic factors that govern small mammal community structure is of critical importance for managing the persistence of forest vertebrates in increasingly fragmented neotropical forest landscapes

A community of small mammals was studied in seasonal semideciduous submontane forest in the state of Mato Grosso, Brazil. This study evaluated the use of edge and matrix pasture, by different small mammal species. Overall, 31 areas were studied, with a total sampling effort of 33,800 trap x nights. Only seven of the 25 species captured in the study sites were able to use the pasture matrix; we classified these species as generalists. Fourteen species were found to be intermediate in habits, being able to use forest edges. We found only four species habitat specialists, occurring only on transect lines in the interior of the fragment, at least 150 m from the edge. Transects located in the pasture matrix and 50 m from the edge had significantly lower species richness and abundance than transects located in the fragment edge or in the interior of the fragment. All transects located within the fragment had similar species richness and abundance, but transects located 50 m from the edge had slightly lower, but non-significant, species richness than transects located 100 m apart from edges. Rarefaction curves demonstrated that only medium-sized fragments (100-300 ha) reached an asymptote of species accumulation. The other areas require further sampling, or more sampling transect, before species accumulation curves stabilize, due to a continued increase in species number.Keywords: edge effects, matrix of pasture, small mammals, forest fragments, Mato Grosso.Efeitos de borda e uso da matriz por uma comunidade de pequenos mamíferos em fragmentos de floresta semidecidual submontana no Mato Grosso, Brasil ResumoUma comunidade de pequenos mamíferos foi estudada em fragmentos de floresta estacional semidecidual submontana no Estado de Mato Grosso, Brasil. Nesse estudo, buscou-se avaliar o uso da borda e da matriz de pastagem pelas diferentes espécies. No total, 31 áreas foram estudadas, com um esforço total de 33.800 armadilhas x noite. Apenas sete das 25 espécies capturadas foram capazes de utilizar a matriz de pastagem, sendo estas consideradas generalistas. Quatorze foram consideradas intermediárias no uso do habitat, sendo capazes de utilizar habitats de borda. Encontramos apenas quatro especialistas, ocorrendo somente nas transecções do interior do fragmento, a aproximadamente 150 m da borda. Dentre todas as transecções utilizadas para amostragem, a disposta na matriz de pastagem, a 50 m da borda, demonstrou ser significativamente menos rica e abundante que as dispostas na borda e no interior dos fragmentos. Todas as transecções localizadas dentro do fragmento tiveram riqueza e abundância de espécies similares, porém a transecção localizada a 50 m da borda teve uma tendência a ser menos rica que a transecção a 100 m. Através de ajustes das curvas de rarefação, somente uma das áreas considerada de médio porte, entre 100 a 300 ha., atingiu uma assíntota. As outras áreas necessitam de um maior número de transecções, a fim de se obter uma estabilização das curvas, pois continuaram a acrescentar espécies.Palavras-cha...

This study was performed to evaluate the effectiveness and safety of unilateral STN lesioning in 23 patients with PD. L-Dopa intake and dyskinesia, Hoehn & Yahr, Schwab & England, and UPDRS motor scores were recorded pre- and postoperatively. Stereotactic MRI and CT and macrostimulation were used to establish target coordinates. A single RF lesion was performed. All patients underwent postoperative MRI. Contralateral tremor arrest and decrease of rigidity and bradykinesia should be regarded as hallmarks to STN stimulation. All recorded parameters were significantly improved after a mean follow-up of 13.5 months. Patients with STN lateral territory lesioning (α <0.05), younger than 61 years and with a duration of the disease between 6 and 9 years (α >0.05) did better than the others. The recurrence rate was 10%. Two patients developed dyskinesias which were completely resolved by a Vim/VOp lesion. Other significant complications were rare. The authors conclude that unilateral STN lesioning is a safe and very effective procedure to treat PD.

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The aim of this work was to determine the predominant winds speeds and directions in the Tangará da Serra region, locate in Southwest of Mato Grosso State, Brazil. So that, it was used meteorological time series from 2003 to 2008, collected through an Universal Anemometer, installed 10 meters above the ground surface in the Automatic Weather Station by the INMET - Meteorology National Institute at the Mato Grosso State University - UNEMAT (14º39' S, 57º25' W and 321,5 m). The predominant winds directions were characterized by the frequency analysis of daily observations from each month of the year. The months that showed higher speeds were: May, June, July, August and September. March showed the lower average and the lower maximum speeds. In all months, the diurnal winds were higher than the nocturnal ones, the strongest winds had occurred during the warmer hours of the day, i.e. from 13:00 to 17:00 h (local time). The monthly maximum gusts had varied from 15.1 m s-1 in June to 30.7 m s-1 in August. In most months of the year there is a predominance of winds from the Northeast (NE), except August and September period, when the winds predominant directions is from the South (S).

Santos-Filho, M.; da Silva, D. J.; Sanaiotti, T. M. Seasonal variation in richness and abundance of small mammals and in forest structure and arthropod availability in forest fragments, at Mato Grosso, Brazil. Biota Neotrop., vol. 8, no. 1, Jan./Mar. 2008. Available from: . Abstract:We captured small mammals in eight forest fragments (43 a 1.411 ha.) during the dry and wet seasons, in southwest Mato Grosso, Brazil, and investigated the variation in small mammal richness and abundance, as well as in forest structure variables (litter volume and canopy openness) and arthropod availability, between the two seasons. Sampling was carried out during the wet season between 2002 and 2003 and in the dry season of 2003. In each fragment, we used Sherman, Tomahawk, snap, and pitfall traps during 10 consecutive days per season, totaling 17,600 trap x nights. In total, we obtained 379 captures of 20 species, seven of marsupials and 13 of rodents. Overall capture success was 2.2% (1.6% during the wet season and 2.7% during the dry season). Total richness, richness of rodents, richness of marsupials, total abundance and abundance of rodents did not varied significantly between seasons. However, marsupial abundance was significantly lower in the dry season, when rainfall is high. Litter volume was significantly higher during the dry season, while arthropod availability was significantly higher during the wet season. Therefore, higher food availability during the wet season may have made trap baits less attractive. In general, the observed variations between dry and wet seasons are in accordance with patterns described in other studies. Keywords: rodents, marsupials, resource availability, seasonality.Santos-Filho, M.; da Silva, D. J.; Sanaiotti, T. M. Variação sazonal na riqueza e na abundância de pequenos mamíferos, na estrutura da floresta e na disponibilidade de artrópodes em fragmentos florestais no Mato Grosso, Brasil. Biota Neotrop., vol. 8, no. 1, Jan./Mar. 2008. Disponível em: .Resumo: Nós capturamos pequenos mamíferos em oito fragmentos florestais (43 a 1.411 ha) nos períodos seco e chuvoso, no sudoeste de Mato Grosso, Brasil, e investigamos a variação na riqueza e na abundância de pequenos mamíferos e em variáveis relacionadas à estrutura da floresta (volume da liteira e abertura do dossel) e à disponibilidade de artrópodes, entre os dois períodos do ano. As amostragens foram realizadas durante o período chuvoso entre 2002 e 2003 e durante período seco de 2003. Em cada fragmento, foram utilizadas armadilhas Sherman, Tomahawk, Snap trap e Pitfall durante 10 dias consecutivos em cada época do ano, totalizando 17.600 armadilhas x noites. Foram obtidas no total 379 capturas de 20 espécies, sendo sete de marsupiais e 13 de roedores, com sucesso de captura de 2,2% (1,6% para o período chuvoso e 2,7% para o período seco). Não houve diferenças significativas na riqueza total, ri...

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Forest fragmentation affects animal population dynamics mainly by loss of habitat and disruption of animal movement. Lizard assemblages are affected by environmental changes, but, depending on their ecological needs, some species might be more vulnerable than others. The southern Amazon suffers accelerated anthropic actions replacing natural environments by farmland (crops and pasture). This region is considerably drier than most of the northern Amazon, with stational semi-deciduous forests fragmented and isolated by pasture, and crops to a lesser extent. Here we report data on lizard assemblages using semi-deciduous forests, forest edge and the surrounding pasture in the southern Amazon in Mato Grosso, Brazil. Lizards were collected in 21 forest fragments (41 to 7,035 ha) surrounded by pasture; using pitfall traps placed on a degradation gradient -from pasture inwards forest fragment (up to 200 m). We collected 242 individuals (14 species, seven families) in 6,300 trap-days. The pattern of species occurrence was largely nested and this nesting was associated with three habitat guilds (generalist, edge-tolerant, and forest species). Although there was no obvious fragmentation effect on lizards diversity community-wise, Hoplocercus spinosus, Bachia dorbignyi, Micrablepharus maximiliani and Kentropyx calcarta were more vulnerable to such effects than all other ten species collected. We verified that assemblages inhabiting pasture and forest edge are a nested subset of assemblages from the forest core. The remnant native vegetation is not distributed homogeneously and lizards species can persist in different parts of the landscape, therefore we recommend the protection of forest remnants as an important conservation action for lizards of the southern Amazon.Keywords: herpetology, Amazon, community ecology, conservation, nestedness.Efeito de borda sobre a comunidade de lagartos em fragmentos de floresta semidecidual submontana ao sul da Amazônia Resumo A fragmentação de florestas afeta a dinâmica das populações animais por meio, principalmente, da perda de habitat e interrupção dos movimentos dos animais. Assembléias de lagartos são afetados por mudanças ambientais, mas, a depender de suas demandas ecológicas, algumas espécies são mais vulneráveis do que outras. A Amazônia Meridional sofre ações antrópicas aceleradas substituindo ambientes naturais por terras voltadas para agropecuária (cultivos e pasto). Esta região é consideravelmente mais seca do que a maior parte das terras ao norte da Amazônia, com florestas estacionais semi-deciduais fragmentadas e isoladas por pasto, e, em menor extensão, cultivos agrícolas. Neste estudo apresentamos informações sobre uso de bordas e pastagem de lagartos confinados a fragmentos de florestas semi-decíduas no sul da Amazônia em Mato Grosso, Brasil. Foram coletados lagartos em 21 fragmentos florestais (41 a 7,035 ha) cercados por pasto; usando armadilhas de queda (pitfalltraps) colocadas em um gradiente de degradação -do pasto em direção ao interior do fragmento floresta...