RESUMO
A series of glasses based on (80-y) TeO2-20 BiCl3-y RE2O3 (y = 0, 0.6 mol%; RE = Nd, Sm, Dy, and Er) were prepared. The thermal stability of the glass was determined by differential scanning calorimetry (DSC). The density and optical energy values of the prepared glass increased in the order of Sm2O3, Nd2O3, Dy2O3, and Er2O3. In addition, the glass doped with Er2O3 had the highest refractive index values compared to the other samples. Subsequently, Judd-Ofelt parameters (Ω2, Ω4, and Ω6) were obtained for the family of RE3+ trivalent rare-earth ions introduced as dopants in a tellurite glass. These parameters were calculated from the absorption spectra for each RE3+. The structures were studied by Raman spectroscopy deconvolution, which determined that TeO4, TeO3, TeO3+1, BiO6, and BiCl6 units had formed. In addition, the structural changes in the glass are related to the intensity ratio of TeO4/TeO3, depending on the type of rare-earth. For the optics and Judd-Ofelt parameters, the ray spectroscopy results of the prepared glass show that it is a good candidate for nonlinear optics fibers, a solid laser material.
RESUMO
As the olfactory system is closely connected with the brain areas responsible for the most crucial alterations in psychiatric populations, especially cognitive and emotional impairments, the study of olfactory processing may be a relevant approach to identify specific markers of alcohol dependence. The aim of this study was to propose the probable olfactory markers for alcohol dependence through a study of the olfactory parameters that involve the central olfactory pathway. We recruited the same 41 alcohol-dependent patients in an early (day 8) and late (day 67) stage of abstinence and 41 controls matched for gender, age, and smoking status. The participants underwent clinical assessments and several olfactory evaluations. The results revealed on one hand, the persistence of decreased intensity of positive emotion (happy), increased intensity of negative emotion (sad), and increased citation of surprise in patients, suggesting the presence of probable trait markers of alcohol dependence. On the other hand, we found decreased hedonic score for pleasant and neutral odorants, and decreased odor familiarity judgment only in the early stage of evaluation as probable state markers for alcohol dependence. These results may be underpinned by several neuropsychological alterations specific to this disease and their evolution after weaning. Further studies are needed to replicate these findings and to confirm the specificity and sensitivity of the olfactory tests in a larger sample of patients. The olfactory perception of all controls must be also retested in order to determine the specific state and/or trait markers of alcohol dependence.
