An analysis was made of the floristic composition of 376 areas of cerrado and Amazonian savanna, encompassing most of the area of such vegetation in Brazil. A total of 951 species of trees and large shrubs was recorded for these areas, of which 334 (35%) occurred at only a single locality (unicates).

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An analysis was made of the floristic composition of 98 areas of cerrado and Amazonian savanna, encompassing most of the area of such vegetation in Brazil. A total of 534 species of trees and large shrubs were recorded for these areas, of which 158 (30%) occurred at a single site only. Such unicates and taxa without determinations to specific level were excluded from the study since they provide no basis for comparison. The data were analysed by three techniques of multivariate analysis: (a) a divisive hierarchical classification by Two-way Indicator Species Analysis (TWINSPAN). (b) an agglomerative hierarchical classification by UPGMA (Unweighted Pair-Groups Method using Arithmetic Averages) using the Sørensen Coefficient of Community (CC) as a measure of similarity, and (c) an ordination by Detrended Correspondence Analysis (DCA). The results from all three methods showed great similarity, demonstrating a strong geographic pattern in the distribution of the flora of the cerrado biome and allowing the recognition of southern (Sâo Paulo and S Minas Gerais), southeastern (largely Minas Gerais), central (Federal District, Goiás and parts of Minas Gerais), central-western (largely Mato Grosso, Goiás and Mato Grosso do Sul) and northern groups (principally Maranhão, Tocantins and Pará), as well as a disjunct group of Amazonian savannas. Soil type (mesotrophic or dystrophic) is an important factor in determining floristic composition. The study demonstrated that cerrado vegetation is extremely heterogeneous: none of the 534 species occurred at all sites and only 28 species were present at 50% or more.

Abstract— The aims of the present study were to investigate the antibacterial properties of glass‐ionomer cements containing different concentrations of chlorhexidine and the possible release of chlorhexidine from the compound. Chlorhexidine gluconate or diacetate was mixed with glass‐ionomer cements and tested in vitro against strains of Lactobacillus casei and mutans streptococci. A spectrophotometric test was used to monitor the release of chlorhexidine from the mixture. In a broth culture test, the higher the concentrations of chlorhexidine in the mixture, the longer the time of antibacterial effect on Streptococcus mutans and the greater the tendency of the material to deteriorate. Agar diffusion tests revealed bacterial inhibition in a dose‐response manner. The tested bacterial strains were similarly inhibited and the antibacterial properties decreased with time. A minor portion of added chlorhexidine was released from the cement. The deterioration of the cements indicates that the material could be useful as a varnish‐like chlorhexidine carrier.

The coexistence of grasses, herbs, shrubs and trees characterizes savannas; therefore, to restore such ecosystems one should consider reintroducing all these growth forms. Currently, little is known about field establishment of most ''Cerrado'' (Brazilian savanna) species that could be used for restoration purposes. Most knowledge on restoration is focused on planting seedlings of tree species from forest physiognomies. Alternatively, direct seeding can be an appropriate method to reintroduce plants of different life forms to restore savannas. We evaluated the initial establishment success under field conditions of 75 ''Cerrado'' native species (50 trees, 13 shrubs, and 12 grasses) in direct seeding experiments in four sites in Central Brazil for 2.5 years. For that, we tagged and measured tree and larger shrub species and estimated ground cover by small shrub and grass species. Sixty-two species became established (42 trees, 11 shrubs and 9 grasses) under field conditions. Thirty-eight of the 48 tagged species had relatively high emergence rates ([10%) and 41 had high seedling survival ([60%) in the first year. Among grasses and small shrub species, Andropogon fastigiatus Sw., Aristida riparia Trin., Schizachyrium sanguineum (Retz.) Alston, Lepidaploa aurea (Mart. ex DC.) H.Rob., Stylosanthes capitata Vogel, S. macrocephala M.B.Ferreira & Sousa Costa, Achyrocline satureioides (Lam.) DC. and Trachypogon spicatus (L.f.) Kuntze had the greatest initial establishment success (up to 30% soil cover). The data on harvesting period, processing mode and field establishment for these 75 species can be readily used in restoration efforts in the ''Cerrado''.