Percorrer por autor "Barracosa, Paulo"
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- Análise às dinâmicas existentes, na defesa da floresta contra incêndios, no concelho de Mortágua MortáguaPublication . Ferreira, Sandra; Viana, Helder; Barracosa, PauloOs incêndios Florestais são um fenómeno próprio de várias regiões, abrangendo aquelas que apresentam clima com características mediterrâneas, como o nosso país. Embora exista unanimidade em considerar a questão dos incêndios florestais, como um problema grave que urge resolver, ou pelo menos minorar, a verdade, é que dadas as suas variadas facetas., nem sempre, os diferentes Intervenientes envolvidos se mostram de acordo quanto à forma de o fazer. A Região Centro tem, nas últimas décadas, sentido o flagelo dos incêndios florestais, e em particular nos concelhos de Distrito de Viseu (DV). No período entre 1990 e 2003, observou-se, no DV, uma área florestal ardida total de mais de 182.500 hectares, sendo cerca de 67.600ha de povoamentos e 114.900ha de matos, com mais de 31700 ocorrências. A análise da evolução dos fogos florestais, no período referido, revela que estes ocorrem com uma frequência cíclica, tendo tido picos de maior área ardida nos anos de 1990, 1996 e 1998 e 2000, não se observando uma relação directa com o número de ocorrências. Este comportamento, embora com as devidas diferenciações, observa-se, de um modo geral, em todos os concelhos do DV, à excepção do concelho de Mortágua, onde esta situação é paradigmática. De facto, a partir do ano de 1995, observa-se neste concelho, uma quase inexistência de área ardida, não obstante, de ser dos concelhos que apresenta uma maior taxa florestal. Com o intuito de contribuir para uma melhor compreensão, sobre as estratégias levadas a cabo pelas Entidades competentes, e pela população do concelho, no planeamento das acções de defesa e combate aos incêndios florestais, que contribuíram para a diminuição dos incêndios e consequentemente da área ardida, foi realizado este trabalho, com o apoio da Associação de Produtores Florestais de Mortágua. Foram levantadas todas as infra-estruturas florestais existentes no concelho e, simultaneamente, foi elaborado um inquérito aos proprietários florestais para conhecer a sua atitude face à floresta.
- Analysis of factors influencing the physical, chemical and sensorial properties of Serra da Estrela cheesesPublication . Guiné, Raquel; Tenreiro, Marlene I. C.; Correia, Ana C.; Correia, Paula; Barracosa, PauloThe objective of this study was to evaluate the chemical, color, textural, and sensorial characteristics of Serra da Estrela cheese and also to identity the factors affecting these properties, namely thistle ecotype, place of production, dairy and maturation. The results demon- strated that the cheeses lost weight mostly during the first stage of maturation, which was negatively correlated with moisture content, being this also observed for fat and protein contents. During maturation the cheeses became darker and with a yellowish coloration. A strong corre- lation was found between ash and chlorides contents, being the last directly related to the added salt in the manufacturing process. The flesh firmness showed a strong positive correlation with the rind harness and the firmness of inner paste. Stickiness was strongly related with all the other textural properties being indicative of the creamy nature of the paste. Adhesiveness was posi- tively correlated with moisture content and negatively correlated with maturation time. The trained panelists liked the cheeses, giving high overall assessment scores, but these were not significantly correlated with the physicochemical properties. The salt differences between cheeses were not evident for the panelists, which was corroborated by the absence of correlation between the perception of saltiness and the analyzed chlorides con- tents. The Factorial Analysis of the chemical and physical properties evidenced that they could be explained by two factors, one associated to the texture and the color and the other associated with the chemical properties. Finally, there was a clear influence of the thistle ecotype, place of production and dairy factors in the analyzed properties.
- Avaliação do rendimento agro-industrial dos frutos e sementes de cultivares de alfarrobeira (ceratonia siliqua l.) No algarvePublication . Barracosa, Paulo; Caetano, Isabel; Batista, MariaA avaliação do rendimento agro-industrial da alfarrobeira no Algarve foi realizada com base em 27 características morfológicas de frutos e sementes de 43 árvores distribuídas por toda a região. A relação entre as características foi estabelecida por uma análise de componentes principais que resultou na separação das árvores em 5 grupos (I-V). Foi estabelecido um modelo de três dimensões, considerado significativo, que evidenciou 52,2% na variação total. A primeira dimensão representa 23,2% e é dominada pelas características largura e peso do fruto e pelas características largura, peso de cada semente e peso do tegumento, gérmen e endosperma. As cultivares `Alfarroba burro´, `Aida´ e `Galhosa´, e algumas árvores bravas foram os exemplares que revelaram maior potencial industrial relativamente aos seus frutos, que apresentaram sementes com elevada percentagem de endosperma e originaram goma com elevado índice de viscosidade. O estudo da biodiversidade com base em árvores não enxertadas dispersas pela região do Algarve constitui um passo fundamental para a implementação de uma estratégia de conservação e melhoramento dos recursos genéticos.
- A Biomassa Verde e Lenhosa dos Espaços Urbanos como Fonte Energética para os Edifícios Públicos da Cidade de ViseuPublication . Viana, Helder Filipe dos Santos; Pinto, Nuno; Costa, Daniela; Barracosa, PauloA biomassa gerada pelos espaços verdes urbanos constitui uma fonte de resíduos significativa que, muitas vezes, é direccionada directamente para aterros podendo ser aproveitada para fins energéticos, nomeadamente no aquecimento térmico de alguns edifícios públicos. O presente trabalho apresenta a quantificação da biomassa verde indiferenciada gerada pelos espaços verdes urbanos, depositada nos pontos de recolha específicos, e da biomassa lenhosa proveniente das podas realizadas nas árvores existentes na cidade de Viseu. Simultaneamente, estimam-se as necessidades energéticas (eléctricas e térmicas), no Verão e Inverno, dos principais edifícios públicos da cidade. A quantificação dos resíduos produzidos anualmente foi avaliada por inquéritos às empresas responsáveis pelas podas das árvores da cidade, à autarquia e ao centro de tratamento dos resíduos sólidos urbanos, para o período de 2004 a 2007. Fez-se também a estimativa a partir da caracterização dendrométrica do parque arbóreo existente, a qual serviu para comparar e validar os resultados obtidos. As necessidades energéticas médias anuais foram estimadas a partir do inquérito realizado, no período entre 2004 e 2006, em 49 edifícios públicos como escolas, unidades de saúde, edifícios da autarquia, entre outros. Os resultados mostram que as necessidades térmicas médias anuais dos edifícios estudados rondam os 109.245,78 GJ. A biomassa produzida ronda as 106,5 t/ano de resíduos lenhosos e 103,3 t/ano de resíduos verdes, os quais foram convertidos em valores de energia. A biomassa unicamente lenhosa poderia suprir cerca de 10,3% das necessidades térmicas de Inverno, das 19 escolas levantadas nestes estudo. Dado que muita da biomassa produzida na cidade não é contabilizada, uma vez que é depositada juntamente com os resíduos sólidos urbanos, o potencial energético destes resíduos poderia ser muito superior.
- Cardo MáximoPublication . Barracosa, Paulo
- Effect of Biochar on Emission of Greenhouse Gases and Productivity of Cardoon Crop (Cynara cardunculus L.)Publication . Barracosa, Paulo; Cardoso, Isabel; Marques, Francisco; Pinto, António; Oliveira, Jorge; Trindade, Henrique; Rodrigues, P.; Pereira, José L.S.Cardoon could be cropped for agro-environmental, industrial, and pharmaceutical purposes. The aim of this study was to assess the effects of biochar on emissions of nitrous oxide (N2O), carbon dioxide (CO2), and methane (CH4), and productivity of cardoon crop. A pot experiment was run outdoors from April to August 2018, with a cardoon plant per pot. The following four treatments, with four replicates each, were applied: control, soil only; mineral, soil amended with mineral fertilizer (2.5 g N m−2); biochar, soil amended with biochar (1 kg m−2); and mineral+biochar, soil amended with mineral fertilizer (2.5 g N m−2) and biochar (1 kg m−2). The morphological characteristics and biomass production of cardoon plants were evaluated, and the fluxes of N2O, CO2 and CH4 were measured by using the closed chamber technique. The application of biochar combined with mineral reduced N2O emissions by 36% and global warming potential (GWP) by 26% relative to mineral. However, the cumulative CO2 and CH4 emissions as well as yield-scaled GWP were not significantly different among amended soil treatments. Furthermore, the biomass production was increased by 50% by the application of biochar combined with mineral fertilizer relative to mineral. It was concluded that biochar combined with mineral fertilizer is recommended as a pathway mitigation for agro-environmental purposes, because it reduces the global warming potential and could increase the biomass production of cardoon plants.
- Effect of Cynara cardunculus L. var. altilis (DC) in inflammatory bowel diseasePublication . Mateus, Vanessa; Estarreja, João; Silva, Inês Filipa Janeiro; Barracosa, Paulo; Teixeira de Lemos, Edite; Pinto, RuiCynara cardunculus L. var. altilis (DC) is a plant generally associated as an ingredient in the Mediterranean diet. The polyphenols present in this plant provide pharmacological and nutritional properties. C. cardunculus L. has been used throughout animal studies, which demonstrated an anti-inflammatory effect. Inflammatory bowel disease (IBD) is a chronic inflammatory disorder of the gastrointestinal tract. Since there is not a known cure, the research of new possible pharmacological approaches is essential. This study aims to evaluate the effect of an aqueous extract of C. cardunculus L. dry leaves in a 2,4,6-Trinitrobenzenesulfonic acid (TNBS)-induced colitis model. Methods: CD-1 mice with TNBS-induced colitis received an intraperitoneal (IP) administration of C. cardunculus L. once per day for 4 days. Results: The C. cardunculus L. demonstrated a beneficial effect in this experimental model of IBD with anti-inflammatory action through the reduction of tumor necrosis factor (TNF)-α levels. It also demonstrated a beneficial influence on the extra-intestinal manifestations related to IBD, with the absence of significant side effects of its use. Conclusions: The extract of C. cardunculus L. dry leaves can become an interesting tool for new possible pharmacological approaches in the management of IBD.
- Effect of drying on the phenolic composition and antioxidant activity of leaves of the thistle (C. cardunculus L.)Publication . Gonçalves, Fernando; Barbosa, Rui; Barracosa, Paulo; Guiné, RaquelIn Portugal, the flowers of Cynara cardunculus L. are traditionally used for the production of cheese “Serra da Estrela”, because they are responsible for the phenomenon of the coagulation of milk. The leaves may be used in diet as teas, soups, stews or salads. The phenolic compounds, such as phenolic acids and flavonoids, have been associated to their potential health benefits.The objective of this work was to evaluate the effect of drying process on the phenolic composition and antioxidant activity of the leaves of three ecotypes of thistle (C. Cardunculus L.) from the region of Viseu, Portugal. For that, the leaves were analyzed after lyophilization and oven drying at two temperatures (50ºC and 70ºC). After each treatment two successive extractions with methanol and acetone solution (60% v/v) were carried out. The extracts obtained were then used to quantify the total phenols and the antioxidant activity (DPPH and FRAP assays). The amount of phenolic compounds present in the sample lyophilized was 82.5 mg GAE/g dry mater, in the sample dried at 50ºC was 22.1 mg GAE/g dry mater, and the sample dried at 70ºC was 8.1 mg GAE/g dry mater. For both, DPPH and Frap assays, a similar behavior of antioxidant activity was observed. Regarding the DPPH assay, The lyophilized sample displayed the highest value (262.3 mol TE/g dry matter) antioxidant capacity, followed by the sample dried at 50ºC (94.2 mol TE/g dry matter) and at 70ºC (9.7 mol TE/g dry matter). When quantified by the FRAP assay, the value of antioxidant activity for samples dried at 50 and 70ºC was respectively 58% and 88% lower than the value obtained for lyophilized sample. No significant difference was possible to observe between different ecotypes in relation to their phenolic and antioxidant composition. The oven drying processes significantly reduced the amount of phenolic compounds and antioxidant activity of thistle leaves, in particular for 70ºC of temperature.
- Effect of drying on the phenolic content and antioxidant activity of thistle flowerPublication . Pedro, Ana; Barracosa, Paulo; Guiné, Raquel; Gonçalves, FernandoThe thistle is a plant that is associated with the production of cheese, as it is responsible for the phenomenon of coagulation of milk. Lately there has been an increased the number of studies about this plant, related to the chemical composition in order to perceive the benefits for human health. The aim of this study was to characterize the thistle flower in relation to its composition in phenolic compounds and also evaluate its antioxidant activity. For that, were studied samples of thistle flower from species Cynara cardunculus L. after freeze-drying and convective drying at different temperatures (40 ºC, 50 ºC and 60 ºC). After each treatment were made from each sample two successive extractions with solutions of methanol (98% v/v) and acetone (60% v/v). The extracts were then used for characterization of the samples in phenolic compounds and determination of antioxidant activity. The results showed that the amount of phenolics and antioxidant activity in the flower thistle varies depending on the drying temperature decrease occurring as they use higher drying temperatures.
- Effect of Thistle Ecotype in the Physical-Chemical and Sensorial Properties of Serra da Estrela CheesePublication . Guiné, Raquel; Tenreiro, Marlene; Correia, Paula; Barracosa, Paulo; Correia, Ana CristinaThe objective of this study was to evaluate the physical and chemical characteristics of Serra da Estrela cheese and compare these results with those of the sensory analysis. For the study were taken six samples of Serra da Estrela cheese produced with 6 different ecotypes of thistle in a dairy situated in Penalva do Castelo. The chemical properties evaluated were moisture content, protein, fat, ash, chloride and pH; the physical properties studied were color and texture; and finally a sensory evaluation was undertaken. The results showed moisture varying in the range 40- 48%, protein in the range 15-20%, fat between 41-45%, ash between 3.9-5.0% and chlorides varying from 1.2 to 3.0%. The pH varied from 4.8 to 5.4. The textural properties revealed that the crust hardness is relatively low (maximum 7.3 N), although greater than flesh firmness (maximum 1.7 N), and also that these cheeses are in fact soft paste type, with measurable stickiness and intense adhesiveness. The color analysis showed that the crust is relatively light (L* over 50), and with a predominant yellow coloration (b* around 20 or over) although with a slight greenish tone (a* negative). The results of the sensory analysis did not show great variability for most of the attributes measured, although some differences were found in attributes such as crust thickness, crust uniformity, and creamy flesh.