Elemental analysis of Brazilian coffee with ion beam techniques: From ground coffee to the final beverage.

Brazilian coffee is well known worldwide due to its quality and richness in taste. The aim of the present study is to provide the elemental characterization of Brazilian coffee along different stages of the drip brewing process. To that end, samples from roasted ground coffee, spent coffee, paper filters and the final beverage were analyzed with one single ion beam technique, namely particle-induced X-ray emission (PIXE). In total, over 140 samples from 8 different Brazilian brands of ground coffee were analyzed. Large differences in some elemental concentrations were observed among different brands and among different batches of a single brand, which leads to high variances in the data. Concerning the beverage preparation, the analysis of the spent coffee shows that the transfer ratio from the ground coffee to the beverage differs for each element. Our results indicate that potassium and chlorine have the highest transfer ratio. Moreover, the concentration of rubidium is relatively high in drinking coffee. Finally, there is no influence of the elemental composition of paper filter in the preparation of drinking coffee.

Changes in the element concentration of the dorsal hippocampus CA1 region during memory consolidation and reconsolidation.

The concentration and distribution of Mg, P, Cl, K, Cu and Zn in the dorsal hippocampus CA1 region of rat brains were studied during memory consolidation and reconsolidation processes stimulated with inhibitory avoidance (IA) tests. Experimental rats were divided into four groups: i) group not submitted to inhibitory avoidance task (IA-N); ii) group submitted to inhibitory avoidance training session (IA-Y); iii) group submitted to inhibitory avoidance reactivation session but did not step down from the platform (IAR-N); and iv) group submitted to avoidance reactivation session and stepped down from the platform (IAR-Y). Elemental concentration and distribution in the CA1 hippocampus region were obtained through the Particle-Induced X-ray Emission (PIXE) technique. The results indicate that the concentration of Mg, P, Cl, K and Cu increased during memory consolidation. During the memory reconsolidation process, the concentrations of Mg, P, Cl and K increased, while Cu and Zn had no significant changes with respect to their basal condition. These results show that the major part of these elements may be engaged in memory consolidation could be also participating in memory reconsolidation. For all elements, the general trend related to their concentration did not change during reconsolidation regardless the presence of a novelty event, i.e. stepping down from the platform.

Effects of Supplemental Acerola Juice on the Mineral Concentrations in Liver and Kidney Tissue Samples of Mice Fed with Cafeteria Diet.

We evaluated the impact of a supplemental acerola juice (unripe, ripe, and industrial) and its main pharmaceutically active components on the concentrations of minerals in the liver and kidney of mice fed with cafeteria diet. Swiss male mice were fed with a cafeteria (CAF) diet for 13 weeks. The CAF consisted of a variety of supermarket products with high energy content. Subsequently, animals received one of the following food supplements for 1 month: water, unripe acerola juice, ripe acerola juice, industrial acerola juice, vitamin C, or rutin. Mineral concentrations of the tissues were determined by particle-induced X-ray emission (PIXE). Our study suggests that the simultaneous intake of acerola juices, vitamin C, or rutin in association with a hypercaloric and hyperlipidic diet provides change in the mineral composition of organisms in the conditions of this study, which plays an important role in the antioxidant defenses of the body. This may help to reduce the metabolism of the fat tissue or even to reduce the oxidative stress.

From alumina nanopores to nanotubes: dependence on the geometry of anodization system.

The Conventional anodization of commercial aluminum sheets with a phosphoric acid electrolyte was employed for the preparation of alumina nanopore and/or nanotube structures. Modifying the system geometry (the ratio of platinum to aluminum electrode areas) controlled the nature of the anodization process (mild to hard). Nanotube formation was observed after low temperature preferential chemical etching of the defective corners of the hexagonal alumina cells using the same solution from the anodization process. Electrode geometry can be used to combine mild and hard anodization with low temperature etching to tune the alumina morphology from 100% nanopores to 100% nanotubos coverage.