Browsing by Issue Date, starting with "2013"
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- Construindo frisos e rosáceas: uma reflexão sobre como fazer matemáticaPublication . Cassis, Ana; Martins, CristinaDecorrente da reflexão realizada durante o estágio da primeira autora, verificamos a importância do professor se preparar para ir ao encontro dos interesses e necessidades dos seus alunos, de modo a proporcionar aulas onde os alunos tenham oportunidade de participar ativamente. Leccionar não é apenas “dar aulas”, é todo um trabalho de casa de preparação, de investigação, de reflexão, articulado com uma componente criativa. Nesta comunicação apresentamos uma experiência de aprendizagem na área da Matemática, incidente numa aula de introdução ao tópico matemático Rosáceas e Frisos, incluído no tema Geometria. Pretendemos apresentar a tarefa proposta, as várias etapas da aula, as dificuldades sentidas pelos alunos e pela professora, bem como as aprendizagens realizadas. Da reflexão realizada ressalvamos, entre outros aspetos, que nesta aula foi essencial os alunos poderem manusear materiais, verem o resultado do seu trabalho e, por eles, chegarem às principais conclusões sobre o tópico em estudo.
- Associação entre o índice de massa corporal e a coordenação motora em criançasPublication . Melo, Maria Mafalda; Lopes, Vitor P.O propósito do estudo foi analisar a associação entre o índice de massa corporal (IMC) e a coordenação motora (CM). Foram avaliadas 794 crianças (seis a nove anos) de ambos sexos na CM, com a bateria de testes KTK. O IMC foi calculado a partir das medidas de peso e estatura [Peso(kg)/Estatura (cm2)]. Quer nas meninas (χ2 = 93,96; p < 0,001) quer nos meninos (χ2 = 46,98; p < 0,001) ocorreram diferenças significativas na CM entre os três grupos do IMC (normoponderais, sobrepeso, obesos). Os normoponderais de ambos os sexos obtiveram melhores resultados do que os sujeitos com sobrepeso e estes obtiveram melhores resultados do que os obesos. A CM está moderada e negativamente associada com o IMC e a associação aumenta durante a infância (-0,16 a -0,50). As crianças com sobrepeso e obesas de ambos os sexos apresentaram menores níveis de CM do que as crianças normoponderais.
- Maternal diversity patterns of Ibero-Atlantic populations reveal further complexity of Iberian honeybeesPublication . Pinto, M. Alice; Henriques, Dora; Neto, Margarida; Guedes, Helena; Muñoz, Irene; Azevedo, João; De la Rúa, PilarDissecting complex diversity patterns typically exhibited by organisms of hybrid zones is among the greatest challenges in evolutionary biology. This has been a long-standing goal of numerous Iberian honeybee studies. Herein, we further contribute to this goal by a fine-scale maternal survey of the Portuguese honeybee populations. In addition to confirm a predicted African ancestry of Portuguese populations and negligible levels of C-lineage introgression, our fine-scale survey revealed unparalleled levels of African maternal diversity and a remarkable north–south cline formed by African haplotypes of distinct ancestry. This survey further highlights the distinctiveness of Apis mellifera iberiensis by showing the existence of highly contrasting diversity patterns between the Atlantic and Mediterranean populations. Our findings further support an ancient natural invasion of the Iberian Peninsula possibly by Apis mellifera intermissa and also by Apis mellifera sahariensis. Protecting this African legacy is of unquestionable importance, especially with Iberia becoming warmer and dryer.
- Agaricus blazei and Lentinus edodes dried formulations: chemical composition and antioxidant activityPublication . Barros, Lillian; Carneiro, Andreia A.J.; Dueñas, Montserrat; Silva, Roberto; Gomes, Eleni; Santos-Buelga, Celestino; Ferreira, Isabel C.F.R.A balanced diet is one of themainstays ofiherapyfor the prevention of the oxidative stress, which if cannot beeliminated, at leastcan be controlled. Food antioxidants may help intrinsic antioxidant mechanisms to fight against oxidative stress. Several mushroom species have been pointed out as sources of antioxidant compounds, besides their nimportant nutritional value. Agaricus blazei and Lentimrs edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations like powdered preparations used as supplements. In the present work the chemical composition (nutrients and bioactive compounds analysed by chromatographic methods) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of Agaricus blazei (APF) and Lentimrs edodes (LPF) from São Paulo, Brazil were evaluated.141 Powder formulations of both species revealed the presence of essential nutrients such as proteins, carbohydrates and unsaturated limy acids. Furthermore, they present low fat content (<2 g/100 g) and can be used in low-caloric diets, just like the mushroom fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 μg/l 00 g and 770 μg/l 00 g, respectively) than LPF (32 μg/ l 00 g and 690 μg/100 g).Both formulations might be used as antioxidant sources to prevent diseases related to oxidative stress.
- Bioactive compounds in Gyromitra esculenta and Helvella lacunosa wild mushrooms from Northeast of PortugalPublication . Leal, Ana Raquel; Barros, Lillian; Martins, Anabela; Ferreira, Isabel C.F.R.The search for foods that can improve health or reduce the risk of disease, has been steadily gaining interest. Mushrooms could be examples of these foods because they are appreciated worldwide for their nutritional properties [1] and bioactive compounds [2]. The chemical characterization of wild species is very important, in order to promote their consumption and conserve their habitats. This feature might place mushrooms in the pharma-nutrition interface. The present study describes the bioactive compounds in two wild mushrooms ( Gyromitra esculenta and Helvelfa lacunosa edible after proper pre-boiling and cooking) collected in Bragança (Northeast Portugal). The individual profiles of organic acids and phenolic compounds were obtained by high performance liquid chromatography coupled to photodiode array detection (HPLC-PDA); tocopherols and free sugars were characterized by HPLC-fluorescence and HPLCRI (refraction index), respectively, and the fatty acids profile was obtained by gas chromatography coupled to flame ionization detection (GC-FID). Gyromitra esculenta was the species with the highest levels of free sugars (6.13 g/1 OOg dw), tocopherols ( 112.83 IJg/1 OOg dw) and phenolic compounds (3.74 mg/1 OOg dw). The major fatty acid found in this specie was linoleic acid (prevalence of PUFA), while Helvella lacunosa presented the highest level of MUFA (prevalence of oleic acid). The Helvella lacunosa sample revealed the highest levels of total organic acids (6.93g/1 00 g dw). Overall, wild mushrooms can be sources of bioactive compounds to be included in nutritional balanced diets.
- Urban landscape irrigation requirements: the case study of Mirandela, PortugalPublication . Ribeiro, A.C.; Ferreiro, GualterThe technological development is leading to the emergence of modern equipment for the automation of irrigation systems, with especial relevance for landscape irrigation systems. Thus, the development of methodologies for irrigation requirements of landscape, that allowed an improvement of the utilization of those technologies and equipment, and consequently to an improvement in irrigation management, is very timely and opportune. In this study, water requirements for landscape irrigation in Mirandela city landscape were estimated. In order to evaluate the sprinkler irrigation systems performance, with the purpose applying an efficient irrigation management program, uniformity experiments were also conducted. The landscape water requirements were estimated with the combination of reference evapotranspiration (ETo) with the landscape coefficient (KL), parameterized from landscape characteristics. The landscape irrigation requirements were calculated based in soil water balance simulations. The results from uniformity experiments show a poor performance of irrigation systems in the majority of landscape hydrozones. The average value of low quarter uniformity distribution was just 25.9 % and uniformity coefficient 43.9 %. The poor performance is analyzed and measures to improve the irrigation performance are suggested such as equipment replacement and an efficient control of variables which influence the sprinkler flow. The total irrigation requirements variability of landscape hydrozones reflects the different type existing vegetation and the characteristics of the places and its environment.
- Gramática derivacional do portuguêsPublication . Rio-Torto, Graça; Rodrigues, Alexandra Soares; Pereira, Isabel; Pereira, Rui; Ribeiro, SílviaNesta Gramática Derivacional descrevem-se os mecanismos, os recursos e os produtos de formação de palavras do português contemporâneo, usando uma linguagem acessível mas assente em aturada investigação por parte dos seus autores, docentes universitários com larga experiência em pesquisa sobre o léxico. Com base nos dados do português europeu e em alguns do português do Brasil, percorrem-se os processos de sufixação (construção de nomes, de adjetivos e de verbos), de prefixação, de composição (erudita e vernácula) e de construção não concatenativa (cruzamento, truncação, siglação, acronímia). A morfologia e a semântica das palavras construídas - sejam isocategoriais ou heterocategoriais - são analisadas tendo em conta as bases que as compõem, os afixos que nelas ocorrem, os processos e as restrições de combinatória, e as áreas denotacionais dos produtos. Precede a descrição dos diferentes paradigmas um capítulo de apresentação dos conceitos básicos e de enquadramento teórico.
- Peninsular war and society: the impacts of the French invasions at Porto (1807-11)Publication . Couceiro, PedroDuring the peninsular war, Porto was invaded two times for french troops (1808- 1809). The Portuguese traditional sources about the French invasions describe, on a patriotic rhetoric and through a denunciative discourse, and beyond a whole series of economic and social constraints and the governmental disorientation that the kingdom suffered by the usurpation of power, a series of abuses and outrages perpetrated by the French and English troops that victimize the population of Porto. Among the many possible approaches, we privilege an assessment of the impacts of war from the people’s daily life in an adverse context. We intend to feel, through their reports and diverse sources of information, the economic, social, organizational and sociability constraints in an adverse context of military occupation of the real urban space, further compounded by the absence of the Portuguese government exile in Brazil and a decreased local authority before the haughty ways of the “enemy”.
- Evaluation of the chemical interactions in co-culture elements of Castanea sativa Miller mycorrhizationPublication . Carvalho, Filipa Arminda; Ferreira, Isabel C.F.R.; Barreira, João C.M.; Barros, Lillian; Martins, AnabelaIn the early steps of mycorrhizal associations an oxidative burst might occur through the rapid production of high amounts of reactive oxygen species in response to external stimuli, increasing the production of antioxidants in plant and/or mycelia. Herein, the effect of mycorrhizal association among Pisolithus arhizus or Paxillus involutus and Castanea sativa Miller (stems and roots) was studied for different co-culture periods, defined for a better comprehension of the chemical interactions in the early stages of mycorrhization (6, 24 and 72 h). Knowledge on the specificities of plant-host interaction provided information about the most suitable fungus to be included in the development of new management strategies, and the fungal species that induced the strongest response with increasing antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) and production of antioxidant compounds (phenolics and tocopherols) and sugars. P. involutus seemed to be the most adequate fungus to mycorrhize with C. sativa. Considering bioactive compounds production, P. arhizus was more efficient since allowed an increase in the contents of sugars and tocopherols in all co-culture elements.
- Synthesis of 2-{2-[5(4)-aryl-2H-[1,2,3]-triazol-4(5)-yl]vinyl}chromen-4-onesPublication . Albuquerque, Hélio; Santos, Clementina M.M.; Silva, Artur; Cavaleiro, JoséChromones are a family of oxygen-containing heterocyclic compounds that have been shown particular relevant biological activity. In what concerns to 2-methylchromones, their reactivity is well-known and allowed to exploit many different kinds of chemical reactions. The acidic character of the 2-methyl group, due to the low electron density at C-2 caused by carbonyl group enable this class of compounds to undergo oxidation, photolysis, cycloaddition and condensation reactions