Fish composition and species richness in eastern South American coastal lagoons: additional support for the freshwater ecoregions of the world.

The relationships between fish composition, connectivity and morphometry of 103 lagoons in nine freshwater ecoregions (FEOW) between 2·83° S and 37·64° S were evaluated in order to detect possible congruence between the gradient of species richness and similarities of assemblage composition. Most lagoons included in the study were <2 km(2) , with a maximum of 3975 km(2) in surface area. Combined surface area of all lagoons included in the study was 5411 km(2) . Number of species varied locally from one to 76. A multiple regression revealed that latitude, attributes of morphometry and connectivity, and sampling effort explained a large amount of variability in species richness. Lagoon area was a good predictor of species richness except in low latitude ecoregions, where lagoons are typically small-sized and not affected by marine immigrants, and where non-native fish species accounted for a significant portion of species richness. Relationships between species and area in small-sized lagoons (<2 km(2) ) is highly similar to the expected number in each ecoregion, with systems located between 18·27° S and 30·15° S attaining higher levels of species richness. Similarities in species composition within the primary, secondary and peripheral or marine divisions revealed strong continental biogeographic patterns only for species less tolerant or intolerant to salinity. Further support for the FEOW scheme in the eastern border of South America is therefore provided, and now includes ecotonal systems inhabited simultaneously by freshwater and marine species of fishes.

[Experimental value of formaldehyde exposure to preserve anatomical findings]. / Valutazione sperimentale dell'esposizione a formaldeide durante il suo utilizzo per la conservazione di reperti anatomici.

Formaldehyde, already classified as potentially carcinogen and recently as "human carcinogen" by IARC, is generally used for fixing and preserving anatomical findings. This reason causes a problem of professional exposure for the operators who use the formaldehyde for this purpose. In this work we present the results of the periodical monitoring which is done for the determination of the exposure at formaldehyde in operating theatres and surgeries, where the operator fill the special container with the anatomical findings andformaldehyde for following tests. The measurements have been done using an instrument that continuously measure the concentration of formaldehyde, based on the infrared spectrometry, in 54 rooms which are operating theatres or surgeries in 9 public hospitals in Campania (Italy). The results show that the long-term exposure limits are not exceeded and that the average of the highest values of concentration obtained during its use was 0.15 +/- 0.04 ppm, that is below the limits. It is important to point out that such a limit was never exceeded during every single measurement. Finally, analyzing statistically the data, we can infer that the probability of exceeding the short-term limit is less than 0.1%, when formaldehyde is used for the purposes mentioned above.

Resin bonding to primary teeth using three adhesive systems.

In vitro bond strengths of three resin adhesive systems were tested using 111 primary teeth. Ninety-six flat dentin surface specimens were divided into six groups consisting of 16 primed or 16 unprimed samples for each adhesive system. The remaining 15 tooth samples were divided into three groups of five to determine each adhesive system's bond strength to primary etched enamel. Resin buttons were polymerized to all specimens with visible light, thermocycled for 2000 cycles between 5 and 55 degrees C, and shear bond strength was measured with a Instron Testing Machine (Instron Engineering Corp, Canton, MA). ANOVA and multiple comparison tests showed that Optibond Multiuse Bonding Agent had a statistically greater mean shear bond strength to primary dentin (20.5 +/- 3.5 MPa) than Prisma Universal Bond 3 Multi-purpose Bonding System (9.1 +/- 4.4 MPa), Scotchbond Multi-purpose Dental Adhesive System (7.3 +/- 3.7 MPa), and primary etched enamel (9.8 +/- 4.4 MPa) at P < 0.05. This study demonstrated that resin adhesive systems may achieve bond strengths to primary dentin comparable to those of primary enamel, and that these bonds may be as strong as bonds to permanent enamel and dentin. These adhesive systems may allow more confident esthetic restoration of primary anterior teeth.

Progressive hemifacial atrophy (Parry-Romberg syndrome). Case report.

Progressive hemifacial atrophy (Parry-Romberg syndrome) is a slowly progressing facial atrophy of subcutaneous fat and the wasting of associated skin, cartilage, and bone. This disorder includes an active progressive phase (2 to 10 years) followed by a burning out of the atrophic process with subsequent stability. This article presents a review of the literature and a case report with unique dental involvement as a result of this disease process.