Frações oxidáveis do carbono orgânico total e macrofauna edáfica em sistema de integração lavoura-pecuária

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Post-Scriptum. Fernando Henrique Cardoso, Alberto Fujimori y la solución del conflicto con Ecuador

PACARINA DEL SUR - REVISTA DEL PENSAMIENTO CRITICO LATINOAMERICANO é uma publicação eletrônica publicada em Mexico, D.F. É publicada 4 vezes por ano. É uma publicação muito aceita e prestigiada internacionalmente.

Actividad antimicrobiana de la solución de nanopartícula de plata en cultivo de Enterococcus faecalis

Objective. The objective of this study was to evaluate the antimicrobial activity of the silver nanoparticles solution in enterococcus faecallis cultures (ATCC 29212), compared with various solutions of sodium hypoclorithe (NaOCl). Material and methods. Five Agar Petri plates were inoculated with E. faecallis and each of them was placed a cellulose dish embedded with silver nanoparticles solution, or a solution of sodium hypochlorite evaluated (Viarzon, Cloralex, Clorox). Chlorhexidine digluconate 2% was used as positive control and sterile saline solution was used as negative control. After 24 hours of incubation at 37ºc, under aerobic conditions, the zones of inhibition of bacterial growth were measured and the results subjected to the statistical t test among the experimental groups (= 5%). Results. The Cloralex showed to be the most effective reflected in the extent of inhibition in relation to other substances (p< 0.05), except that the chlorhexidine digluconate 2% (p> 0.05). The solution of silver nanoparticles provided a greater zone of inhibition than the sodium hypochlorite solution (Clorox) and Viarzon (p< 0.05). Clorox and Viarzon didn't provide zones of inhibition and were similar to each other (p> 0.05). Conclusions. The solution of silver nanoparticles presents antimicrobial activity in cultured E. faecallis, even higher than other commercial forms of sodium hypochlorite. Further studies should be carried out to determine its viability as irrigating solution in endodontics (AU)

Nematofauna edáfica em sistemas de uso do solo na microrregião de Chapadinha-MA

Pós-graduação em Agronomia (Ciência do Solo) - FCAV

Fauna edáfica na dinâmica sucessional da Mata Atlântica em floresta estacional semidecidual na Bacia do Rio Paraíba do Sul - RJ

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do gradiente interior-borda-matriz, e do tipo de matriz sobre a entomofaúna edáfica em fragmentos de cerrado

edge effect. Thus, under the influence of the adjacent matrix, fragments undergo microclimatic alterations that accentuate changes in species composition and community structure. In order to better understand edge and matrix effects on the richness and abundance of edaphic arthropods, this study assessed: (a) the difference between habitat (fragment) and non-habitat (matrix); (b) whether there is a continuous interior-edge-matrix gradient; and (c) the difference between matrices for arthropod orders richness and abundance. We selected 15 landscapes, 5 of which contained a cerrado fragment surrounded by sugarcane cultivation, 5 with a cerrado fragment within eucalyptus and 5 with a cerrado fragment within pasture. In each landscape the soil fauna was collected along with the soil and then extracted with the aid of the modified Berlese-Tullgren funnel. We chose the orders Coleoptera, Collembola, Mesostigmata and Oribatida for analysis, and after separation of the individuals we used model selection analysis via AIC. The model type fragment x matrix was the most likely to explain richness, total and relative abundances of the four orders (wAICc between 0,6623 and 1,0). The model of edge distance (edge effect) was plausible to total abundance and relative abundance of Mesostigmata order (wAICc=0,2717 and 0,186). Local environmental variables (soil texture, temperature and relative humidity), and fragment size were also measured to avoid confounding factors and were not presented as plausible models to explain the patterns. So edaphic arthropods, despite protecting themselves under the ground, are extremely sensitive to fragmentation, even with the replacement of natural habitat by agricultural use, such as sugarcane, pasture and eucalyptus. This group should be studied environmental impact assessments because provides important ecosystem se ravincde s inacnludd eisd ainn efficient bio-indicator