Clustering of groundwaters by Q-mode factor analysis according to their hydrogeochemical origin: A case study of the Cariri Valley (Northern Brazil) wells

Factor analysis was applied to 56 groundwater samples collected from wells located in the Araripe Sedimentary Basin, in the north-east of Brazil. The parameters are a set of 9 physicochemical, chemical, and isotope data, constituted by electrical conductivity (EC), ionic concentrations of Ca2+, Mg2+, Na+, K+, Cl−, SO42−, alkalinity and δ18O0/00. In R-mode factor analysis, the first 3 factors explain 62% of the variance, their loadings allowing the interpretation of hydrogeochemical processes that take place in the area. Q-mode factor analysis on the 56 water samples decreases space dimensionality to 6, explaining 93% of the total database information. With the aid of a scalar and angular measurement method, objects were clustered, resulting in 11 groups classified according to their inherent characteristics, related to their hydrogeological origin.Keywords: hydrogeochemistry, R-mode factor analysis, Q-mode factor analysis, Araripe sedimentary basin, Cariri valle

Raman Spectroscopy of Amino Acid Crystals

In this chapter, we investigate the Raman spectra of proteinogenic amino acid crystals. Amino acids are fundamental organic molecules that compose polypeptides (a linear chain of amino acids) and proteins (folded polypeptides with specific functions) found in all living beings. Surprisingly, the number of these basic molecules is not more than 22 (20 of them commonly known as the standard amino acids, plus pyrrolysine and selenocysteine). They are defined as a molecule formed by an NH2 group, a COOH group, a lateral chain (the R group), and a hydrogen atom, all of them connected to a single carbon, the α-carbon. Interestingly, α-amino acids show chirality, i.e., they present different distributions of group of atoms around the α-carbon, being defined as l- and d-form. For amino acids and proteins found in the living beings, the l-form is the dominant form, although some exceptions have been discovered in the last decades. In this chapter, we present the Raman spectra of all standard amino acids and discuss the different kinds of vibrations found, comparing them. As complementary part of the work, we present results on vibrational properties of some amino acids using Raman spectroscopy when subjected to specific conditions, with variation in temperature or pressure. Finally, we present some perspectives as the investigation of purines, a group of molecules associated with the DNA molecule

ANÁLISE DA INTERNAÇÃO POR NEOPLASIA MALIGNA DO ENCÉFALO DO BRASIL NO PERÍODO DE 2011 A AGOSTO DE 2022

INTRODUÇÃO: A neoplasia maligna do encéfalo é uma forma de tumor cerebral caracterizado pela proliferação de células anormais no interior da região. Essa patologia está inserida dentro do grupo das neoplasias malignas do Sistema Nervoso Central (SNC), as quais representam entre 1,4 a 1,8% de todos os tumores malignos presentes no mundo. OBJETIVOS: Analisar a quantidade e as variáveis dos índices de internação por neoplasia maligna do encéfalo no Brasil. MÉTODO: Trata-se de um estudo quantitativo e retrospectivo com coleta de dados do Departamento de Informática do Sistema Único de Saúde - DATASUS. A pesquisa foi realizada mediante informações de estatísticas vitais no grupo de Morbidade Hospitalar do SUS (SIH/ SUS). Foram analisados os dados disponíveis pelo CID 10 de ambos os sexos, faixas etárias e região com maior incidência. RESULTADOS: Foram constatados no período analisado 161.269 casos de internação por neoplasia maligna do encéfalo. No tocante ao sexo, 52,28% dos casos são do sexo masculino e 47,72% do sexo feminino. Das faixas etárias, as internações são mais prevalentes entre 50 a 59 anos de idade com 19,22% dos casos totais de internação por neoplasia maligna do encéfalo, sendo 43,63% da região sudeste os maiores casos de notificações. CONCLUSÕES: Depreende-se, portanto, que o número de internações por neoplasia maligna do encéfalo é maior em pessoas do sexo masculino, sobretudo na faixa etária dos 50 a 59 anos, com destaque marcante para a região sudeste do país. PALAVRAS-CHAVE: Neoplasia. Cérebro. Internaçã

Unveiling the structure and composition of titanium oxide nanotubes through ion exchange chemical reactions and thermal decomposition processes

In this paper we report the ion exchange reactions and the thermal decomposition of titanium oxide nanotubes, obtained by hydrothermal treatment of TiO2 and NaOH. Based on these results we propose a new composition for the as-prepared nanotubes as Na2Ti3O7.nH2O. Our results also suggest that nanotube walls have structure similar to those observed in the layer of the bulk Na2Ti3O7. Depending on how the washing process is performed on the nanotubes (water or acid solutions) the Na+ content can be modified via the exchange reaction of Na+ by H+. Thus, a general chemical formula was also proposed: Na2-xHxTi3O7 .nH2O (0 < x < 2), x being dependent on the washing process