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This study determined and correlated the anthocyanin profile of Brazilian tropical (São Francisco Valley in Pernambuco), and temperate wines (Rio Grande do Sul), and temperate Chilean wines (Valle del Colchagua and Central Valley), with their geographical origins, using high performance liquid chromatography (HPLC) combined with a chemometric method, by applying Principal Component Analysis (PCA). The concentrations and the percentage of the nine anthocyanins (delphinidin-3-glucoside, cyanidin-3-glucoside, petunidin-3glucoside, peonidin-3-glucoside, malvidin-3-glucoside, peonidin-3-glucoside-acetate, malvidin-3-glucosideacetate, peonidin-3-glucoside coumarate and malvidin-3-glucoside coumarate) were obtained and the values varied greatly according to the cultivar, vintage and country. The results demonstrated that wines from Rio Grande do Sul showed the highest levels of anthocyanin glucosides, which served as the discrimination factor for the chemometric analysis of the samples. Wine samples from the São Francisco Valley preferentially seem to follow the biosynthetic route Naringenin → Kaempferol → Cyanidin-3-Glucoside → Peonidin-3-Glucoside, unlike the samples from the other two regions (Chile and Rio Grande do Sul) that seem to follow the route Naringenin → Kaempferol → Delphinidin-3-Glucoside → Petunidin-3-Glucoside → Malvidin-3-Glucoside. The samples of the Syrah variety from the São Francisco Valley had higher concentrations of individual and total anthocyanins than the Chilean, suggesting the potential for successful adaptation of the cultivation of this grape to the terroir of the Brazilian northeast.

A espectroscopia de emissão em plasma induzido por laser (LIBS) foi avaliada para a detecção de resíduos de disparo de arma de fogo (GSR) nas mãos de um suspeito. Para desenvolver o procedimento, 114 amostras foram obtidas pressionando um pequeno pedaço de fita adesiva contra a região dorsal das mãos de não-atiradores, atiradores após o disparo e de atiradores após terem lavado as mãos com sabão e água. As fitas foram analisadas diretamente em um equipamento LIBS baseado em um policromador echelle com resolução temporal construído em laboratório. Os espectros foram obtidos a partir da aplicação de um único pulso de laser em 20 locações diferentes, espalhadas uniformemente sobre a superfície da fita, para assegurar uma amostragem eficiente na detecção de resíduos de disparo. Os espectros mostram uma assinatura com linhas de emissão características de bário e chumbo. Quando os dados espectrais foram submetidos à técnica de reconhecimento de padrão SIMCA (Modelagem Independente e Flexível por Analogia de Classe), atiradores e não-atiradores foram corretamente classificados. O método baseado em LIBS e SIMCA demonstrou ser não-destrutivo da evidência do crime e permitiu discriminar as amostras coletadas de voluntários não-atiradores e atiradores, mesmo após a lavagem das mãos.Laser induced breakdown spectroscopy (LIBS) is further developed for the detection of gunshot residue (GSR) on the hands of a suspected shooter. To develop the procedure, 114 samples were obtained by pressing a small piece of adhesive tape against the dorsal region of the hands of nonshooters, of shooters just after firing a weapon, and of shooters after washing their hands with soap and water. The tapes were analyzed directly in a time-resolved echelle based LIBS system, assembled in the laboratory, and 20 single laser pulses, spread uniformly on the tape surface, were shown to be enough to ensure the detection of true positives. The spectra obtained by LIBS from the tape present a signature with emission lines that are attributed to barium and lead. After the spectral data was submitted to a pattern recognition method SIMCA (Soft Independent Modeling of Class Analogy), shooters and non-shooters were corrected classified. The method based on LIBS and SIMCA has been demonstrated to be non-destructive of crime evidence and enabled discrimination between the samples collected from non-shooter volunteers and shooter volunteers before and after washing their hands.Keywords: laser-induced breakdown spectroscopy, gunshot residues, SIMCA, screening analysis, LIBS IntroductionGunshot residues (GSR) evidence has been considered essential during recent decades in forensic science as it makes it possible to determine if a suspect has fired, been in crime location or come into contact with a firearm.Despite the recent advances in the production of the so called clean ammunitions and well sealed guns, the use of cheap and widespread standard fire arms and propulsive charge remains associated with the majority of hand-armed crimes.1 At the moment of shooting ...

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