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Today׳s most commonly applied bonding effectiveness tests are criticized for their high variability and low reliability, the latter in particular with regard to measuring the actual strength of the adhesive interface. Objectives: in continuation of previous research conducted at dentin, we hereby aimed to validate the novel mini-interfacial fracture toughness (mini-iFT) test on its applicability to assess bonding effectiveness of contemporary adhesives when bonded to enamel. Methods: The 3-step etch&rinse (E&R) adhesive OptiBond FL (Kerr), the 2-step self-etch (SE) adhesive Clearfil SE Bond (Kuraray Noritake) and the two multi-mode adhesives Clearfil S 3 Bond Plus (Kuraray Noritake) and Scotchbond Universal (3M ESPE), both used following a 2-step E&R and 1-step SE mode, were applied to clinically relevant, flattened enamel surfaces. A composite (Filtek Z100; 3M ESPE) build-up was made in layers. After 1-week water storage at 37 °C, all specimens were sectioned perpendicular to the interface to obtain rectangular sticks. A mini-iFT notch was prepared at the adhesive-enamel interface using a thin diamond blade under water cooling. Finally, the specimens were loaded in a 4-point bending test until failure. Results: the mini-iFT onto human enamel was significantly higher for the adhesives applied in E&R mode versus those applied in SE mode. The lowest mini-iFT was found for the adhesives applied following a 1-step SE approach. SEM fracture analysis revealed that all fractures originated at the adhesive-enamel interface and that the induced crack propagated preferentially along this interface. Conclusion: mini-iFT appeared a valid alternative method to assess the mechanical properties of adhesive-enamel interfaces. [ABSTRACT FROM AUTHOR]

Abstract: Environmental determinants of global patterns in species richness are still uncertain. The Metabolic Theory of Ecology (MTE) proposes that species richness patterns can be explained by environmental temperature acting on the metabolism of ectothermic organisms. However, the generality of this theory has been questioned due to its low fit to the geographic variation in species richness of different taxonomic groups. Here, we investigated whether the MTE drives elapid richness, testing the non-stationarity of the relationship between the natural logarithm of species richness (ln S) and the inverse function of temperature (1/kT) using a geographically weighted regression (GWR). The relationship between ln S and 1/kT varied systematically over space and showed non-stationarity. Few tropical locations were consistent with MTE predictions, whereas other regions fitted differently. Although the slope of the GWR model ranged from low to high, the temperature did not predict species richness strongly on average and did not limit the upper values of richness. The response of richness to temperature in some areas might reflect a recent history of colonization and diversification of species across tropical and subtropical regions. In regions not affected by temperature, species richness should be structured by other biotic and abiotic interactions. This scenario reveals that the non-stationarity of the relationship would be linked to idiosyncrasies in the sample sites, which can drift the magnitude or change the relationship between species richness and temperature throughout space. [Copyright &y& Elsevier]

Abstract: At lower spatial scales, richness spatial patterns probably lead to more complex ecological–evolutionary interactions. In this paper, we used a “deconstruction” approach to evaluate the Cerrado breeding bird''s richness, according to their habitat use categories (independent, semi-dependent and dependent on forest habitats). Six environmental variables and current human population size were used as predictors of species richness. Moran''s I coefficients revealed strong spatial autocorrelation in ordinary least squares multiple regression residuals, and thus a Principal Coordinate of Neighbour Matrices (PCNM) was used to evaluate the influence of richness predictors, minimizing the problems caused by spatial autocorrelation. Models generated for total richness and for species richness by habitat categories were compared. We showed that, despite the total richness being more concentrated in south and southeast regions of Cerrado, these patterns changed when analysing semi-dependent and dependent forest habitat species, demonstrating a spatial variation in richness for these categories. The PCNM analyses demonstrated that, for total species richness, only partial coefficients of AET and temperature were significant. For independent forest richness, significant partial regression coefficients were found for AET, PET, TEMP and PREC, whereas for semi-dependent forest habitats richness, only AET was significant. On the other hand, for dependent of forest richness, a significant positive coefficient was found for precipitation and for human population. Most spatial variation in richness can be explained by joined effects of geographic structure and environmental predictors. These analyses reveal that deconstruction can be a step to a more effective understanding of richness patterns and their environmental drivers. [Copyright &y& Elsevier]

Vitamin D deficiency is associated with risk for a first cardiovascular event in the general population, possibly because of inflammation, insulin resistance, and neurohumoral activation. However, its relation with outcomes in acute coronary syndromes has not been reported. To test the hypothesis that severe deficiency of vitamin D is independently associated with cardiovascular mortality during ACS, 206 patients admitted for unstable angina, noneST-segment elevation myocardial infarction, or ST-segment elevation acute myocardial infarction had 25-hydroxyvitamin D serum levels measured at admission. Severe vitamin D deficiency was defined a priori as a value ≤10 ng/ml. The average concentration of vitamin D was 20 ± 8.2 ng/ml, and 10% of patients were severely deficient (95% confidence interval 6.6% to 15%). Cardiovascular mortality during hospitalization took place in 14 patients, an incidence of 6.8%. Patients with severe vitamin D deficiency had in-hospital cardiovascular mortality of 24%, significantly higher than the 4.9% observed in the remaining patients (relative risk 4.3, 95% confidence interval 1.8 to 10, p = 0.001). After adjustment for Global Registry of Acute Coronary Events (GRACE) score, Gensini angiographic score, and potential confounding variables, severe deficiency of vitamin D remained an independent predictor of in-hospital cardiovascular mortality (odds ratio 14, 95% confidence interval 1.2 to 158, p = 0.03). In conclusion, severe vitamin D deficiency is independently associated with in-hospital cardiovascular mortality in patients with acute coronary syndromes. [ABSTRACT FROM AUTHOR]