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- New method for determination of (E)resveratrol in wine based on microextraction using packed sorbent and ultra-performance liquid chromatographyPublication . Gonçalves, João; Câmara, José S.An ultra-fast and improved analytical methodology based on microextraction by packed sorbent (MEPS) combined with ultra-performance LC (UPLC) was developed and validated for determination of (E)-resveratrol in wines. Important factors affecting the performance of MEPS such as the type of sorbent material (C2, C8, C18, SIL, and M1), number of extraction cycles, and sample volume were studied. The optimal conditions of MEPS extraction were obtained using C8 sorbent and small sample volumes (50–250mL) in one extraction cycle (extract–discard) and in a short time period (about 3 min for the entire sample preparation step). (E)-Resveratrol was eluted by 1 250mL of the mixture containing 95% methanol and 5% water, and the separation was carried out on a highstrength silica HSS T3 analytical column (100 mm 2.1 mm, 1.8mm particle size) using a binary mobile phase composed of aqueous 0.1% formic acid (eluent A) and methanol (eluent B) in the gradient elution mode (10 min of total analysis). The method was fully validated in terms of linearity, detection (LOD) and quantification (LOQ) limits, extraction yield, accuracy, and inter/intra-day precision, using a Madeira wine sample (ET) spiked with (E)-resveratrol at concentration levels ranging from 5 to 60mg/mL. Validation experiments revealed very good recovery rate of 9575.8% RSD, good linearity with r2 values 40.999 within the established concentration range, excellent repeatability (0.52%), and reproducibility (1.67%) values (expressed as RSD), thus demonstrating the robustness and accuracy of the MEPSC8/UPLC-photodiode array (PDA) method. The LOD of the method was 0.21mg/mL, whereas the LOQ was 0.68mg/mL. The validated methodology was applied to 30 commercial wines (24 red wines and six white wines) from different grape varieties, vintages, and regions. On the basis of the analytical validation, the MEPSC8/UPLC-PDA methodology shows to be an improved, sensitive, and ultra-fast approach for determination of (E)-resveratrol in wines with high resolving power within 6 min.
- Profiling allergic asthma volatile metabolic patterns using a headspace-solid phase microextraction/gas chromatography based methodologyPublication . Caldeira, M.; Barros, António S.; Bilelo, M. J.; Parada, A.; Câmara, J. S.; Rocha, Sílvia M.Allergicasthmarepresentsanimportantpublichealthissuewithsignificantgrowthovertheyears,especially in the paediatric population. Exhaled breath is a non-invasive, easily performed and rapid method forobtainingsamplesfromthelowerrespiratorytract.Inthepresentmanuscript,themetabolicvolatile profiles of allergic asthma and control children were evaluated by headspace solid-phase microextraction combined with gas chromatography–quadrupole mass spectrometry (HS-SPME/GC–qMS). The lack ofstudiesinbreathofallergicasthmaticchildrenbyHS-SPMEledtothedevelopmentofanexperimental design to optimize SPME parameters. To fulfil this objective, three important HS-SPME experimental parameters that influence the extraction efficiency, namely fibre coating, temperature and time extractions were considered. The selected conditions that promoted higher extraction efficiency corresponding to the higher GC peak areas and number of compounds were: DVB/CAR/PDMS coating fibre, 22◦C and 60min as the extraction temperature and time, respectively. The suitability of two containers, 1L Tedlar® bags and BIOVOC®, for breath collection and intra-individual variability were also investigated. The developed methodology was then applied to the analysis of children exhaled breath with allergicasthma(35),fromwhich13hadalsoallergicrhinitis,andhealthycontrolchildren(15),allowing to identify 44 volatiles distributed over the chemical families of alkanes (linear and ramified) ketones, aromatic hydrocarbons, aldehydes, acids, among others. Multivariate studies were performed by Partial LeastSquares–DiscriminantAnalysis(PLS–DA)usingasetof28selectedmetabolitesanddiscrimination between allergic asthma and control children was attained with a classification rate of 88%. The allergic asthma paediatric population was characterized mainly by the compounds linked to oxidative stress, such as alkanes and aldehydes. Furthermore, more detailed information was achieved combining the volatile metabolic data, suggested by PLS–DA model, and clinical data.
- História da literatura infantil na Madeira: reflexos de um mundo em mudançaPublication . Ramos, Dina Isabela Lemos; Paolinelli, Luísa Marinho AntunesO aumento substancial do número de livros infantis publicados na Madeira, ou produzidos por autores nativos da Ilha, mais cedo ou mais tarde, daria como resultado a escrita de um ensaio teórico acerca deste assunto. Esta é a essencial finalidade deste trabalho. Percorrendo diversas matérias em redor da Literatura Infantil pretende-se dar uma ideia da sua evolução e crescimento na Ilha. Através de uma contextualização inicial do género Literatura Infantil, fornecem-se diversos dados acerca deste, mesmo que por vezes ainda exista controvérsia acerca da sua legitimação. Para a percepção do desenvolvimento da Literatura Infantil na Madeira é estritamente necessário rever esta mesma matéria a nível nacional. Para além disso, para considerar o desenvolvimento da Literatura Infantil na Ilha, deve-se ter em mente a existência de uma tradição oral popular. Na Madeira, a religião cristã e a escola juntaram-se na educação das crianças por meio dos livros. Os livros direccionados para um leitor com menos idade, mas não menos exigente que o adulto, passaram por várias fases de maturação ao mesmo tempo que a posição da criança na sociedade ia mudando. Depois de uma análise geral, dá-se conta que existe uma variedade de temas, motivos e finalidades que seguem uma transformação na sociedade, o avanço tecnológico, a conjuntura histórico-político, e a mudança de mentalidades da população. Há, por fim, que ter em consideração a relação cada vez mais profunda que a literatura estabelece com outras artes, como o Teatro, a música e a Banda Desenhada, ou, em particular, a ilustração. Para finalizar, é importante rever a condição da crítica literária existente sobre escritos na Madeira.