Browsing by Issue Date, starting with "2015"
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- Syntax and biology: a teaching experience with the Laboratory NotebookPublication . Rebelo, H.; Aguín-Pombo, D.In the 1st Cycle of Primary Education at the University of Madeira, preservice teachers have different courses including Portuguese and Natural Sciences. Education in Portugal from primary school to university level follows a unitary pedagogy circumscribed to every discipline rather than a global approach. We believe this pedagogic approach could benefit from an entirely different organization in which, instead of having a fragmented program, would have, when possible, pedagogical proposals and knowledge together. We demonstrate the usefulness of this interdisciplinary approach, bringing together two areas of knowledge (Syntax and Biology) that generally consider themselves apart, but that have much to give each other for the benefit of students and pupils at primary schools.
- Análise de sobrevivência e valores extremos em RPublication . Abreu, Ana Maria; Gouveia-Reis, DéliaO software R ´e uma ferramenta extremamente u´til para a investiga¸c˜ao estat´ıstica. No entanto, a prolifera¸c˜ao de bibliotecas (na ordem dos milhares) dificulta o r´apido e eficiente acesso a todas as possibilidades em cada uma das ´areas desta ciˆencia. Uma forma de limitar esta procura ´e aceder `a task view correspondente, se existir. Pelos motivos descritos, neste trabalho procura-se compilar informac¸˜ao relevante nas ´areas de an´alise de sobrevivˆencia e de valores extremos, de modo a minimizar as dificuldades referidas. A abordagem na an´alise de sobrevivˆencia, que possui task view, ser´a sobretudo atrav´es de exemplos. Nos valores extremos ser´a dada uma vis˜ao geral do que existe, uma vez que nesta ´area n˜ao h´a task view.
- Quantification of furanic derivatives in fortified wines by a highly sensitive and ultrafast analytical strategy based on digitally controlled microextraction by packed sorbent combined with ultrahigh pressure liquid chromatographyPublication . Perestrelo, Rosa; Silva, Catarina L.; Câmara, José S.An improved, reliable and powerful analytical strategy based on digitally controlled microextraction by packed sorbent (MEPS) combined with ultrahigh pressure liquid chromatography (UHPLC) was validated for the simultaneous identification and quantification of major furanic derivatives, namely 5-hydroxymethyl-2-furaldehyde (5HMF), 5-methyl-2-furaldehyde (5MF), 2-furaldehyde (2F) and 2-furyl methyl ketone (2FMK), in fortified wines. To enhance the extraction efficiency of the target furanic derivates, several influencing extraction parameters, such as number of loading cycles, nature of elution solvent and elution volume, were evaluated and optimized. In addition the ability of different MEPS sorbent materials, namely C2, C8, C18, SIL, M1, R-AX, R-CX and PGC, were also tested. The optimal analytical conditions involved loading 3×200 μL of wine samples through a C8 sorbent in a MEPS syringe placed in the semi-automatic eVolH syringe followed by elution using 200 μL MeOH:H2O (95:5, v/v). The furanic derivates separation was achieved using a CORTECS UPLC(®) C18 analytical column in an ultrafast chromatographic run (within 4 min). The method performance was assessed for dry/medium dry (D/MD) and sweet/medium sweet (S/MS) model wines in terms of selectivity, linearity, limit of detection (LOD), limit of quantitation (LOQ), accuracy, precision and matrix effect, using model wine matrix-matched calibration. Good linearity was obtained with a regression coefficient (r(2)) higher than 0.992. A good precision was attained (RSD<5%) and low LODs were achieved for D/MD (4.5-129.3 ng L(-1)) and S/MS (6.9-285.2 ng L(-1)) model wines. The quantification limits (LOQ) for D/MD model wines ranged from 14.9 to 431.0 ng L(-1), whereas for S/MS model wines range from 23.1 to 950.5 ng L(-1). The method also afforded satisfactory results in terms of accuracy, ranging from 74 to 97% for D/MD wines and between 84 and 99% for S/MS wines. The MEPS(C8)/UHPLC-PDA analytical strategy was successfully applied to analyze furanic derivates in 26 fortified Madeira wines from different types (D/MD, S/MS) and ages. The obtained results revealed the analytical strategy as a suitable tool which combines sensitivity, effectiveness, reduced analysis time and simple analytical procedure. Principal component analysis (PCA) suggested that fortified wines can be organized based on their age on PC1, which are mainly characterized by 5HMF.
- Effects of Melatonin-aided therapy on the Glutathione antioxidant system activity and liver protectionPublication . Popov, Serguey S.; Shulgin, Konstantin K.; Popova, Tatyana N.; Pashkov, Aleksander N.; Agarkov, Aleksander A.; Carvalho, Miguel A. A. Pinheiro deAcute hepatitis results from oxidative stress triggered by hepatotoxic drugs causing liver injury and the activation of caspases cascade. The glutathione antioxidant system protects against reactive oxygen species and mitigates development of these processes. The effectiveness of silymarin, a polyphenolic flavonoid, essenthiale, composed of phosphatidyl choline, and melaxen, a melatonin-correcting drug, as hepatoprotectors has been investigated. The variation of 6-sulfatoxymelatonin (aMT6s), resulting from the biotransformation of melatonin, and GSH has been measured. The activities of caspase-1 and caspase-3, glutathione antioxidant system, and NADPH-generating enzymes were determined. The aMT6s decreases in patients with drug hepatitis and recovers with administration of mexalen. GSH increased in the presence of the studied hepatoprotectors. Pathologically activated caspase-1 and caspase-3 decreased their activities in the presence of hepatoprotectors with melaxen showing the highest effect. The positive effect of melatonin appears to be related to the suppression of decompensation of the glutathione antioxidant system functions, recovery of liver redox status, and the attenuation of inhibition of the NADPH supply.
- Multiplexed-shotgun-genotyping data resolve phylogeny within a very recently derived insular lineagePublication . Mort, Mark E.; Crawford, Daniel J.; Kelly, John K.; Santos-Guerra, Arnoldo; Sequeira, Miguel Menezes de; Moura, Mónica; Caujapé-Castells, JuliPremise of the study: Endemic plants on oceanic islands have long served as model systems for studying patterns and processes of evolution. However, phylogenetic studies of island plants frequently illustrate a decoupling of molecular divergence and ecological/morphological diversity, resulting in phylogenies lacking the resolution required to interpret patterns of evolution in a phylogenetic context. The current study uses the primarily Macaronesian fl owering plant genus Tolpis to illustrate the utility of multiplexed shotgun genotyping (MSG) for resolving relationships at relatively deep (among archipelagos) and very shallow (within archipelagos) nodes in this small, yet diverse insular plant lineage that had not been resolved with other molecular markers. • Methods: Genomic libraries for 27 accessions of Macaronesian Tolpis were generated for genotyping individuals using MSG, a form of reduced-representation sequencing, similar to restriction-site-associated DNA markers (RADseq). The resulting data fi les were processed using the program pyRAD, which clusters MSG loci within and between samples. Phylogenetic analyses of the aligned data matrix were conducted using RAxML. • Key results: Analysis of MSG data recovered a highly resolved phylogeny with generally strong support, including the fi rst robust inference of relationships within the highly diverse Canary Island clade of Tolpis . • Conclusions: The current study illustrates the utility of MSG data for resolving relationships in lineages that have undergone recent, rapid diversifi cation resulting in extensive ecological and morphological diversity. We suggest that a similar approach may prove generally useful for other rapid plant radiations where resolving phylogeny has been diffi cult.
- Self-assembled peptide nanoarchitectures: applications and future aspectsPublication . Sharma, Prem; Rathi, Brijesh; Rodrigues, João; Gorobets, NikolayAmong the diversity of natural and synthetic compounds being studied and applied for human welfare, peptides able to develop nanostructures are currently under special attention of scientists. In this review, we focus on such properties of peptides and various kinds of intramolecular interactions allowing their ability to form different shapes of nanoassemblies. We have also discussed the applications of self-assembled peptides in various biomedical fields where they can be employed as cargo to target delivery of drugs, genes, in tissue engineering, regenerative medicines, and biosensors.
- Entre o céu e a terra, a glória de Roma: a estátua de Augusto da Prima Porta revisitadaPublication . Reis, Telmo Corujo dos
- Amino acids and biogenic amines evolution during the estufagem of fortified winesPublication . Pereira, Vanda; Pereira, Ana C.; Pérez Trujillo, Juan P.; Cacho, Juan; Marques, José C.The current study was focused on the impact of accelerated ageing (heating step) on the amino acid and biogenic amine profiles of fortified wines. In this sense, three Madeira wines from two commonly used grape varieties (one red and the other white) were analysed during the heating, at standard (45∘ C, 3 months) and overheating (70∘ C, 1 month) conditions, following a precolumn derivatization procedure using iodoacetic acid, o-phthaldialdehyde, and 2-mercaptoethanol, carried out in the injection loop prior to RP-HPLC-FLD detection. Eighteen amino acids were identified, with arginine being the most abundant. An important decrease of the amino acid levels was detected during the standard heating (up to 30%), enhanced up to 61% by the temperature increase. Cysteine, histidine, and asparagine revealed the greatest decreases at 45∘ C. Conversely, some amino acids, such as asparagine, slightly increased. Four biogenic amines were identified but always in trace amounts. Finally, it was observed that the accelerated ageing did not favour the biogenic amine development. The results also indicate that the heating process promotes the amino acid transformation into new ageing products.
- Robots to learn statistics and citizenshipPublication . Lopes, P. C.; Fernandes, E.In this paper we report a small part of a broader study that is being carried out under the first author PhD, whose goal is to understand how the use of technologies, specially robots, helps students to develop statistical literacy, reasoning and thinking and their ability to problem-solving, producing meaning and enhancing learning. We assume as phenomenon under study - learning (of statistics and citizenship). In this paper we will analyse how learning of statistics and citizenship occurred throughout the search of the winner of a robot race.