Robust Bayesian analysis of heavy-tailed stochastic volatility models using scale mixtures of normal distributions

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

Dental bleaching with a 10% hydrogen peroxide product: a six-month clinical observation

Context: The possibility of bleaching vital teeth with peroxide-based products considerably revolutionized esthetic dentistry. Aim: The aim of this clinical study was to evaluate tooth color change and dental sensitivity after exposure to preloaded film containing a 10% hydrogen peroxide whitening system (Opalescence Trθswhite Supreme). Materials and Methods: A total of 13 volunteers, aged 18 to 25 years, participated in this study. The patients used the whitening system once a day for 60 minutes during the 8-day study. For maxillary incisors and canines, the color change was visually evaluated with the Vita color scale before, immediately, and six months after the treatment. Tooth sensitivity was evaluated during the daily gel applications. All whitening applications were done in office and under the supervision of a dental professional. Statistical Analysis Used: The results were analyzed using the Friedman Test (nonparametric repeated measures ANOVA) at a level of 5%, and Dunn's Multiple Comparison Test at the level of 5%. Results: It was verified that the original mean color values observed at the baseline analysis differed significantly from those observed immediately after bleaching, as well as from those seen in the analysis at six months ( P = 0.001). There was no significant difference between the mean color values observed in the immediate time and in the analysis at six months ( P = 0.474). No tooth sensitivity was observed in any patients. Conclusion: It was concluded that the bleaching technique using the 10% hydrogen peroxide system was effective in a short period of time without tooth sensitivity during applications.

Isoflavones supplementation of a probiotic soy product: effects on quality characteristics and isoflavones profile

The aim of the present study was to investigate the effect of isofl avones supplementation of a fermented soy product on its sensory acceptance, physicochemical properties and probiotic cell viable count. Additionally we also investigated the ability of the mixed starter cultures (Enterococcus faecium CRL 183 and Lactobacillus helveticus 416) to modify the isofl avones profi le of soy product during the fermentation process. Three products were analysed: soy product fermented with E. faecium CRL 183 and L. helveticus 416, isofl avonessupplemented soy product (fermented with E. faecium CRL 183 and L. helveticus 416; 50mg/100g, Isofl avin®, Galena, Brazil) and unfermented soy product. A panel of judges evaluated the acceptability of the samples on a nine point structured hedonic scale. The chemical composition namely fat, protein, ash and total carbohydrate contents, pH, enumeration of viable Lactobacillus spp. and Enterococcus spp. and quantifi cation of isofl avones using HPLC were investigated. All determinations were conducted after 7 days storage at 10°C. The sensorial acceptance was reduced in the isofl avones-supplemented soy product, but this effect was not signifi cant compared to the sample without isofl avones addition. Chemical composition did not differ (p<0.05) among the samples. Cell viable counts were reduced and total fermentation time was longer in the isofl avonessupplemented soy product, suggesting that the isofl avone addition could inhibit the starter cultures. However, all the products may be considered probiotic since they exhibited lactic acid bacterial populations varying from 2.3 x 109 up to 1.22 x 1010 CFU/mL. Fermentation of soymilk did not change the isofl avones profi le. In conclusion, it was possible to obtain a fermented soy product containing a high isofl avones concentration, adequate sensory and chemical characteristics and lactic acid bacterial viability suffi ciently high to characterize the product as a probiotic. The mixed starter culture was not able to convert the glycoside isofl avones into aglycone or produce equol during the fermented soy product processing.