Synthesis, texture, and photoluminescence of lanthanide-containing chitosan-silica hybrids

Three different types of photoluminescent hybrid materials containing trivalent lanthanide (Ln3+ ) Eu3+, Tb3+) ions, chitosan, and silica have been prepared with different structural features. The different silica sources lead to diverse microstructures of hybrid materials, with silica being homogeneously dispersed in the chitosan materials (LnChS-H), or forming a core-shell morphology. Postsynthesis treatment is necessary for embedding the luminescent probe. The Ln3+-based materials have been investigated by photoluminescence spectroscopy (12-300 K). The chitosan-Eu3+-related local environment is maintained in the EuChS-H hybrid material. The emission features of the core-shell materials are characterized by the presence of two Eu3+ distinct local environments, one associated with the chitosan core and the other with the silica shell

The effect of sauna bathing on lipid profile in young, physically active, male subjects

Objectives: The aim of the study was to evaluate effects of Finnish sauna bathing on lipid profile in healthy, young men. Material and Methods: Sixteen male subjects (20–23 years) were subjected to 10 sauna bathing sessions in a Finnish sauna every 1 or 2 days. The mean sauna temperature was 90±2°C, while humidity was 5–16%. Each session consisted of three 15-minute parts and a 2-minute cool-down between them. The following measurements were taken before and after the sauna sessions: body mass, heart rate, body skinfold thickness. The percentage fat content and then, the lean body mass were calculated. Total cholesterol, triacylglycerols, lipoprotein cholesterol LDL and HDL were measured in blood samples. Results: A statistically significant decrease of total cholesterol and LDL cholesterol was observed during 3 weeks of sauna treatment and in the week afterwards. A significant decline in triacylglycerols was found directly after the 1st and 24 h directly after the 10th sauna session. After the 10th sauna session the level of HDL cholesterol remained slightly increased, but this change was not statistically significant. A decrease in blood plasma volume was found directly after the 1st and the last sauna bathing session due to perspiration. An adaptive increase in blood plasma volume was also found after the series of 10 sauna sessions. Conclusions: Ten complete sauna bathing sessions in a Finnish sauna caused a reduction in total cholesterol and LDL cholesterol fraction levels during the sessions and a gradual return of these levels to the initial level during the 1st and the 2nd week after the experiment. A small, statistically insignificant increase in HDL-C level and a transient decline in triacylglycerols were observed after those sauna sessions. The positive effect of sauna on lipid profile is similar to the effect that can be obtained through a moderate-intensity physical exercise