Browsing by Author "Santos, F."
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- Alkyl deoxy-arabino-hexopyranosides: synthesis, surface properties, and biological activitiesPublication . Silva, Filipa; Goulart, Margarida; Justino, Jorge; Neves, Ana; Santos, F.; Caio, J.; Lucas, S.; Newton, A.; Sacoto, D.; Barbosa, E.; Santos, M. S.; Rauter, A. P.Octyl and dodecyl glycosides possessing 2-deoxy-arabino-hexopyranoside moieties belonging to the D-and L-series in their alpha- and beta-forms were synthesized by reaction of an acetyl protected glycal with octanol or dodecanol, catalyzed by triphenylphosphine hydrobromide, followed by deprotection. Their surface properties were studied and discussed in terms of the adsorption and aggregation parameters, pC(20), CMC, and gamma(CMC). The antimicrobial activities were assessed using the paper disk diffusion and broth dilution methods. Both the octyl and dodecyl 2-deoxy beta-D-glycosides inhibited significantly Enterococcus faecalis, a microbe also highly susceptible to dodecyl 2,6-dideoxy-alpha-L-arabino-hexopyranoside. This compound was particularly active against Bacillus cereus and Bacillus subtilis, presenting for both Bacillus species a minimal inhibitory concentration of the same order of magnitude and a minimal lethal concentration even smaller than that obtained for chloramphenicol, a bioactivity which remained unaltered after 1 year solution storage at 4 degrees C. In addition, activity over Listeria monocytogenes was also observed. Direct cytotoxicity and genotoxicity of the glycosides were determined by proliferative index (mitotic index) evaluation in peripheral human lymphocytes of healthy donors. All compounds induced acute toxicity effects, and the response was dose dependent for the alpha-anomer of both the alkyl 2-deoxy-arabino-hexopyranosides and for the corresponding dodecyl beta-anomer, what suggests that non-toxic but still bioactive concentrations may be found for these compounds
- Flora adventícia de pomares de macieirasPublication . Vasconcelos, T.; Filipe, N.; Santos, F.; Franqueira, JoséA partir de levantamentos florísticos efectuados em 61 pomares de macieira nas regiões da Beira Interior e do Ribatejo e Oeste, obteve-se uma listagem de 389 espécies adventícias. As notações de abundância e frequência permitiram definir as espécies que causam ou poderão vir a causar aos fruticultores maiores dificuldades de combate. As relações existentes entre as espécies adventícias e os factores «região geográfica», «textura», «pH(H20)», «P2O5 assimilável» e «K2O assimilável», foram estudadas com base na análise de perfis ecológicos e da informação mútua. Através desta análise foi possível determinar os factores com maior importância na distribuição das infestantes nos pomares de macieira observados e constituir diversos grupos ecológicos.
- Flore adventice de vergers de poirierPublication . Vasconcelos, T.; Santos, F.; Franqueira, José; Filipe, N.Parmi plusieurs especes d'adventices recencees dans les releves floristiques effectues dans les vergers de poirier des regions du Ribatejo, de l'Oeste et de Beira Interior, les Legumineuses, les Composees et les Graminees sont les plus representatives. Les especes ont ete classees en trois categories salon leur frequence relative : superieure a 75%, comprise entre 50 et 75%, et comprise entre 25 et 50%. On a analyse les profils ecologiques des frequences corrigees pour les 20 especes, ayant une information mutuelle plus elevee pour les facteurs ecologiques suivants: "rsgion", "texture", "pH (H20)" ."P205 assimilable" et "K20 assimilable".
- The effect of handlebar height and bicycle frame length on muscular activity during cycling: a pilot studyPublication . Conceição, Ana; Milheiro, A.; Parraca, J.; Rocha, F.; Espada, M.; Santos, F.; Louro, HugoThe cycling literature is filled with reports of electromyography (EMG) analyses for a better understanding of muscle function during cycling. This research is not just limited to performance, as the cyclist’s goal may be rehabilitation, recreation, or competition, so a bicycle that meets the rider’s needs is essential for a more efficient muscular activity. Therefore, the purpose of this study was to understand the contribution of the activity of each of the following muscles: TD (trapezius descending), LD (latissimus dorsi), GM (gluteus maximus), and AD (anterior deltoid) in response to different bicycle-rider systems (handlebar height; bicycle frame length) and intensities in a bicycle equipped with a potentiometer. Surface EMG signals from muscles on the right side of the body were measured. A general linear model test was used to analyze the differences between muscle activation in the test conditions. Effect sizes were calculated using a partial Eta2 (η 2 ). The level of significance was set at 0.05. Muscle activation of different muscles differs, depending on the cycling condition (Pillai’s trace = 2.487; F (36.69) = 9.300; p < 0.001. η 2 = 0.958), mostly during low intensities. In high intensities, one specific pattern emerges, with a greater contribution of GM and TD and weaker participation of LD and AD, enhancing the cycling power output.