Utilização de georadar na caracterização da evolução do dano estrutural de uma parede: ensaio à escala real

Ao longo do tempo o património edificado deteriora-se devido a causas naturais ou antrópicas. A acção sísmica é um factor que pode provocar danos estruturais nas paredes das construções tradicionais, por vezes até imperceptíveis à vista desarmada. A Geofísica aplicada proporciona técnicas de elevada resolução que permitem detectar alvos de pequenas dimensões, como por exemplo fendas na estrutura interna de paredes. O georadar, técnica não invasiva, utiliza impulsos electromagnéticos de frequências variando de dezenas de MHz a GHz que permitem uma elevada resolução dos meios a investigar. A utilização destas técnicas na caracterização interna de paredes exige a utilização de gamas de frequências elevadas (> 1GHz) de forma que pequenas fissuras sejam detectadas. A evolução do dano de uma estrutura tradicional de alvenaria sujeita a diferentes solicitações, como as acções sísmicas, pode ser monitorizada por medidas de georadar. Por outro lado, poderá ainda ser viável a utilização de medidas de georadar na avaliação da eficácia de soluções de reparação de fissuras por injecção de caldas. Na região de Aveiro as paredes estruturais eram tradicionalmente realizadas em adobe. Para avaliar a viabilidade da aplicação do georadar na caracterização interna destas estruturas, no Departamento de Engenharia Civil da Universidade de Aveiro foi construída uma parede em adobe, com blocos de adobe recuperados das construções existentes, e segundo as técnicas e métodos tradicionais. Esta parede foi inicialmente sujeita a uma solicitação cíclica de amplitude crescente que lhe produziu danos estruturais significativos. Estes danos foram posteriormente reparados com recurso à injecção de uma calda à base de cal hidráulica. Após reparação dos danos, a parede foi reforçada com uma malha polimérica embebida no reboco e esta foi sujeita a um ensaio cíclico de amplitude crescente até ao seu colapso. Foram recolhidos dados de georadar (1.6 GHz) sobre a parede, antes e durante o ensaio da parede reforçada, que permitiram caracterizar os danos iniciais, a eficiência da injecção da calda na colmatação das fissuras e a evolução dos danos estruturais provocados ao longo do ensaio. Os resultados são discutidos e permitem justificar plenamente a utilização do georadar na caracterização interna de estruturas de paredes. Demonstra-se que o georadar é uma ferramenta não intrusiva de elevada resolução a utilizar na avaliação do dano em construções existentes

Effects of trophism on nutritional and nutraceutical potential of wild edible mushrooms.

Consumption of wild growing mushrooms has been preferred to eating of cultivated fungi in many countries of central and Eastern Europe. Nevertheless, the knowledge of the nutritional value of wild growing mushrooms is limited. The present study reports the effects of trophism on mushrooms nutritional and nutraceutical potential. In vitro antioxidant properties of five saprotrophic (Calvatia utriformis, Clitopilus prunulus, Lycoperdon echinatum, Lyophyllum decastes, Macrolepiota excoriata) and five mycorrhizal (Boletus erythropus, Boletus fragrans, Hygrophorus pustulatus, Russula cyanoxantha, Russula olivacea) wild edible mushrooms were accessed and compared to individual compounds identified by chromatographic techniques. Mycorrhizal species revealed higher sugars concentration (16-42 g/100 g dw) than the saprotrophic mushrooms (0.4-15 g/100 g). Furthermore, fructose was found only in mycorrhizal species (0.2-2 g/100 g). The saprotrophic Lyophyllum decastes, and the mycorrhizal species Boletus erythropus and Boletus fragrans gave the highest antioxidant potential, mainly due to the contribution of polar antioxidants such as phenolics and sugars. The bioactive compounds found in wild mushrooms give scientific evidence to traditional edible and medicinal uses of these species

Saprotrophic and mycorrhizal will edible mushrooms from Portuguese mycoflora as a source of nutrients and nutraceuticals.

In many countries of central and Eastern Europe consumption of wild growing mushrooms has been preferred to eating of cultivated fungi. Nevertheless, the knowledge of the nutritional value of wild growing mushrooms is limited

Magnetocaloric Effect In The Rni5 (r = Pr, Nd, Gd, Tb, Dy, Ho, Er) Series

In this paper, the magnetocaloric effect in the hexagonal intermetallic compounds belonging to the RNi5 series was calculated using a Hamiltonian including the crystalline electrical field, exchange interaction, and the Zeeman effect. Experimental work was performed and the two thermodynamics quantities, namely, isothermal entropy change and adiabatic temperature change were obtained for polycrystalline samples using heat capacity measurements, and compared to the theoretical predictions.70131344281-134428-6Pecharsky, V.K., Gschneidner Jr., K.A., (1997) Phys. Rev. Lett., 78, p. 4494Gschneidner Jr., K.A., Pecharsky, V.K., (1997) Rare Earths: Science, Technology and Application III, , edited by R. C. Bautista, C. O. Bounds, T. W. Ellis, and B. T. Kilbourn (The Minerals, Metals and Materials Society, Warendale, PATegus, O., Bruck, E., Buschow, K.H.J., De Boer, F.R., (2002) Nature (London), 415, p. 150Wada, H., Tanabe, Y., (2001) Appl. Phys. Lett., 79, p. 20(2001) Appl. Phys. Lett., 79, p. 3302Wada, H., Morikawa, T., Taniguchi, K., Shibata, T., Yamada, Y., Akishige, Y., (2003) Physica B, 328, p. 114Von Ranke, P.J., De Oliveira, N.A., Gama, S., (2004) J. Magn. Magn. Mater., 277, p. 78Von Ranke, P.J., De Campos, A., Caron, L., Coelho, A.A., Gama, S., De Oliveira, N.A., unpublishedVon Ranke, P.J., De Oliveira, N.A., Gama, S., (2004) Phys. Lett. A, 320, p. 302Von Ranke, P.J., Lima, A.L., Nóbrega, E.P., Da Silva, X., Guimarães, A.P., Oliveira, I.S., (2001) Phys. Rev. B, 63, p. 024422Von Ranke, P.J., Pecharsky, V.K., Gschneidner, K.A., Korte, B.J., (1998) Phys. Rev. B, 58, p. 14436Buschow, K.H.J., Van Der Goot, A.S., (1971) Acta Crystallogr., Sect. B: Struct. Crystallogr. Cryst. Chem., 27, p. 1085Stevens, K.W.H., (1952) Proc. Phys. Soc., London, Sect. A, 65, p. 209Radwanski, R.J., Kim-Ngan, N.H., Kayzel, F.E., Franse, J.J.M., Gignoux, D., Schmitt, D., Zhang, F.Y., (1992) J. Phys.: Condens. Matter, 4, p. 8853Tishin, A.M., Magnetocaloric effect in the vicinity of phase transitions (1999) Handbook of Magnetic Materials, 12, pp. 395-524. , edited by K. H. J. Buschow (North-Holland Elsevier, Amsterdam, the Netherlands), Chap. 4Marzouk, N., Graig, R.S., Wallace, W.E., (1973) J. Phys. Chem. Solids, 34, p. 15Barthem, V.M.T.S., Gignoux, D., Schmitt, D., (1989) J. Magn. Magn. Mater., 78, p. 56Zhang, F.Y., Gignoux, D., Schmitt, D., Franse, J.J.M., Kayzel, F.E., Kim-Ngan, N.H., Radwanski, R.J., (1994) J. Magn. Magn. Mater., 130, p. 108Morellon, L., Algarabel, P.A., Ibarra, M.R., Del Moral, A., Gignoux, D., Schmitt, D., (1996) J. Magn. Magn. Mater., 153, p. 17Barthem, V.M.T.S., Gignoux, D., Nait-Saada, A., Schmitt, D., Takeuchi, A.Y., (1989) J. Magn. Magn. Mater., 80, p. 142Gignoux, D., Givord, D., Del Moral, A., (1976) Solid State Commun., 19, p. 891Andreeff, A., Valter, V., Grissmann, H., Kaun, L.P., Lipold, B., Mats, V., Franzkhaim, T., (1978) JINR Rapid Commun., 1978, pp. 14-11324Marzouk, N., Graig, R.S., Wallace, W.E., (1973) J. Phys. Chem. Solids, 34, p. 1

Learn+Fun! Social Media and Gamification sum up to foster a community of practice during an Emergency Medicine Rotation

Purpose: Medical students and clinical teachers thrive to establish meaningful learning relationships in overwhelmed and ever-shorter clinical rotations. The challenge for medical educators is to design pedagogical approaches capable of bonding students and teachers into the same community of practice (CoP). In this work, the authors explored how Social Media and Gamification strategies sum up to boost medical students’ participation in a blended learning strategy to teach Emergency Medicine. Method: Final year medical students (n = 462) from 5 consecutive years were included in a longitudinal study with historical controls and were divided into three groups. The first group (CONTROL; n = 125) had access to a blended learning strategy; the second group (FACE; n = 179) had access to the blended learning strategy and interacted with a fictional facilitator in Social Media; and the third group (GAME; n = 158) had access to the former strategies plus a gamification approach. Results: Social media and gamification progressively increased students’ participation in the online course as measured by the number of hours logged on from an average of 60 h in CONTROL to 87 h in FACE and 140 h in GAME (P < 0.01). There was a positive and significant correlation between students’ grades on cognitive tests and OSCEs exams with the online participation. Both strategies nurtured students’ sense of belonging to the community of Emergency Medicine and improved their self-regulation to study. Discussion: Social Media and Gamification catalyzed the consolidation of a shared identity for students and teachers, which fostered the creation of a community of practice and increased the participation of students in learning activities. Keywords: Community of practice, Social media, Medical education, Gamificatio

Magnetocaloric effect in the RNi5 (R=Pr, Nd, Gd, Tb, Dy, Ho, Er) series

In this paper, the magnetocaloric effect in the hexagonal intermetallic compounds belonging to the RNi5 series was calculated using a Hamiltonian including the crystalline electrical field, exchange interaction, and the Zeeman effect. Experimental work was performed and the two thermodynamics quantities, namely, isothermal entropy change and adiabatic temperature change were obtained for polycrystalline samples, using heat capacity measurements, and compared to the theoretical predictions.701

Fruiting body, spores and in vitro produced mycelium of ganoderma lucidum from northeast Portugal : a comparative study of the antioxidant potential of phenolic and polysaccharidic extracts

Ganoderma lucidum is one of the most extensively studied mushrooms due to its medicinal properties. Herein, a systematic study was carried out in order to compare the antioxidant activity of phenolic and polysaccharidic extracts from fruiting body, spores and mycelium, obtained in three different culture media, of G. lucidum from Northeast Portugal. Phenolic extracts were characterized using high-performance liquid chromatography coupled to photodiode array detection, while polysaccharidic extracts were hydrolysed and further characterized using HPLC and refraction index detection. In general, the phenolic extracts (Ph) proved to have higher antioxidant potential than their corresponding polysaccharidic extracts (Ps). Amongst phenolic extracts, FB-Ph provided the highest antioxidant activity (EC50 ≤ 0.6 mg/ml) and the highest content in total phenolics (~29 mg GAE/g extract) and phenolic acids (p-hydroxybenzoic and p-coumaric acids). S-Ps was the polysaccharidic extract with the best antioxidant activity (EC50 ≤ 2 mg/ml); nevertheless, the highest levels of total phenolics were obtained in FB-PS (~56 mg GAE/g extract), while the highest levels of total polysaccharides (~14 mg PE/g extract) and individual sugars were observed in mycelia obtained from solid culture media, M-PDA-Ps and M-sMMN-Ps. The free radical scavenging properties, reducing power and lipid peroxidation inhibition of G. lucidum seemed to be correlated with phenolic compounds mostly in a free form, but also linked to polysaccharides.The authors are grateful to Fundação para a Ciência e a Tecnologia (FCT, Portugal) and COMPETE/QREN/UE (research project PTDC/AGR-ALI/110062/2009) for financial support. S.A. Heleno (BD/70304/2010) and L. Barros (BPD/4609/2008) thank to FCT, POPH-QREN and FSE for their grants. The GIP-USAL is financially supported by the Spanish Ministerio de Ciencia e Innovación through the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063), and Junta de Castilla y León (Grupo de Investigación de Excelencia, GR133)

Alternative Splicing at a NAGNAG Acceptor Site as a Novel Phenotype Modifier

Approximately 30% of alleles causing genetic disorders generate premature termination codons (PTCs), which are usually associated with severe phenotypes. However, bypassing the deleterious stop codon can lead to a mild disease outcome. Splicing at NAGNAG tandem splice sites has been reported to result in insertion or deletion (indel) of three nucleotides. We identified such a mechanism as the origin of the mild to asymptomatic phenotype observed in cystic fibrosis patients homozygous for the E831X mutation (2623G>T) in the CFTR gene. Analyses performed on nasal epithelial cell mRNA detected three distinct isoforms, a considerably more complex situation than expected for a single nucleotide substitution. Structure-function studies and in silico analyses provided the first experimental evidence of an indel of a stop codon by alternative splicing at a NAGNAG acceptor site. In addition to contributing to proteome plasticity, alternative splicing at a NAGNAG tandem site can thus remove a disease-causing UAG stop codon. This molecular study reveals a naturally occurring mechanism where the effect of either modifier genes or epigenetic factors could be suspected. This finding is of importance for genetic counseling as well as for deciding appropriate therapeutic strategies