1,297 research outputs found
VI Workshop on Computational Data Analysis and Numerical Methods: Book of Abstracts
The VI Workshop on Computational Data Analysis and Numerical Methods (WCDANM) is going to be held on June 27-29, 2019, in the Department of Mathematics of the University of Beira Interior (UBI), Covilhã, Portugal and it is a unique opportunity to disseminate scientific research related to the areas of Mathematics in general, with particular relevance to the areas of Computational Data Analysis and Numerical Methods in theoretical and/or practical field, using new techniques, giving especial emphasis to applications in Medicine, Biology, Biotechnology, Engineering, Industry, Environmental Sciences, Finance, Insurance, Management and Administration. The meeting will provide a forum for discussion and debate of ideas with interest to the scientific community in general. With this meeting new scientific collaborations among colleagues, namely new collaborations in Masters and PhD projects are expected. The event is open to the entire scientific community (with or without communication/poster)
Susceptibilidade à Erosão Hídrica na Bacia da Ribeira Seca (Santiago, Cabo Verde)
Na Ilha de Santiago, em Cabo Verde, a erosão hídrica é o processo que afecta áreas
mais extensas. A ocorrência de aguaceiros intensos e concentrados no tempo e no espaço
promovem uma marcada erosividade das precipitações, com forte irregularidade regional. A
grande variabilidade dos declives e das formas das vertentes, associadas à diversidade
litológica, bem como à multiplicidade de ocupação do solo, permitem condições de
erodibilidade muito contrastadas no espaço.
O objectivo deste trabalho é obter um mapa de susceptibilidade à erosão hídrica para a bacia
da Ribeira Seca (Santiago oriental) com base no modelo digital do terreno (MDT), nos mapas
geológico e de ocupação do solo e na distribuição da erosividade das precipitações.
Verifica-se que o sector sudeste da bacia é o mais susceptível à erosão hídrica, pois nele
ocorrem a maior concentração diária das precipitações e as condições geomorfológicas e de
coberto do solo de mais elevada erodibilidade.In Santiago Island, Cape Verde, the hidric erosion is the most widespread process. The
rainfall events are high concentred and intense promoting strong precipitation erosivity and
have a great spatial variability. The high diversity of slopes steepness, lanforms, geological
units and land cover is responsible for the great spatial contrast of erodibility conditions.
The goal of this study is to produce a susceptibility hidric erosion map for Ribeira Seca basin
(Santiago oriental) based on a Digital Elevation Model (DEM) and on geological, land cover
and rain erosivity maps.
The results show that the south-eastern area of the basin is the most susceptible to hidric
erosion, due to local daily rainfall concentration and geomorphological and land cover
conditions of higher erodibility
Evolução das características sensoriais de vinhos brancos da casta encruzado conservados em diferentes tipos de barricas de madeira de carvalho
info:eu-repo/semantics/publishedVersio
Campus Criminal Victimization among Higher Education Students: A Diagnosis of Local Security in Porto
This study addressed and characterized direct and indirect criminal victimization among college students and examined the associations between victimization and other variables. The participants were 775 students of both genders with a mean age of 21.76 years. Data were collected through self-reports using the “Diagnosis of Local Security Questionnaire”. Overall, 8.6% of the students reported direct victimization, and 39.7% reported indirect victimization. The most reported crimes were robbery and theft, while the least prevalent were sexual offense, domestic violence, and fraud. Most incidents involved a stranger and occurred at night in the street. Direct victimization was associated with gender, age, marital status, student level, attendance status, and institution domain. There were significant associations between indirect victimization and nationality, student type, attendance status, and institution domain. The perception of (in)security was significantly associated with victimization. Therefore, physical and social measures are necessary to reduce crime and increase security.FCT (Foundation for Science and Technology)info:eu-repo/semantics/publishedVersio
A Predictive Strategy Based on Volatile Profile and Chemometric Analysis for Traceability and Authenticity of Sugarcane Honey on the Global Market
Sugarcane honey (SCH) is a syrup produced on Madeira Island and recognized by its
unique aroma, a complex attribute of quality with an important influence on the final consumer’s
acceptance of the product, and determined by a complex mixture of a large number of volatile organic
compounds (VOCs) generated during its traditional making process and storage. Therefore, the
purpose of this study was to establish the volatile profile of genuine SCH produced by a regional
certified producer for seven years and compare it with syrups from non-certified regional producers
and with producers from different geographical regions (Spain, Egypt, Brazil and Australia), as
a powerful strategy to define the volatomic fingerprint of SCH. Different volatile profiles were
recognized for all samples, with 166 VOCs being identified belonging to different chemical classes,
including furans, ketones, carboxylic acids, aldehydes and alcohols. Chemometric analysis allowed
(i) the differentiation between all syrups, being more pronounced between SCH and other syrups;
and (ii) the identification of 32 VOCs as potential markers for the traceability and authenticity of
SCH on the global market.info:eu-repo/semantics/publishedVersio
Chemical Differentiation of Sugarcane Cultivars Based on Volatile Profile and Chemometric Analysis
Sugarcane (SC) is a perennial grass widely cultivated in tropical and subtropical regions. However, its cultivation in
Europe is residual, where Madeira Island, Portugal, is the only region where SC continues to be extensively cultivated. For the first
time, the volatile profiles of regional cultivars were established by solid-phase microextraction combined with gas chromatography−
mass spectrometry. Different volatile profiles for each cultivar were recognized, identifying 260 volatile organic compounds
belonging to 15 chemical classes, such as aldehydes, alcohols, ketones, hydrocarbons, esters, and terpenes. Chemometric analysis
procedure, namely, one-way ANOVA with Tukey’s test, principal component analysis, partial least-square analysis, linear
discriminant analysis, and hierarchical clustering analysis, allowed the differentiation between all regional cultivars. This study
represents an important contribution for the maintenance of biodiversity and subsistence of the SC industry in Europe. Furthermore,
it is also a valuable contribution to establish the typicality of traditional SC-based products, such as SC honey.info:eu-repo/semantics/publishedVersio
Effect of processing and storage on the volatile profile of sugarcane honey: A four-year study
Sugarcane honey (SCH) is a syrup from Madeira Island recognized by its unique and excellent aroma, associated
to volatile organic compounds (VOCs) generated during the well-defined five stages of its traditional making
process. The establishment of volatile profile throughout all SCH-making stages during four years, allowed the
evaluation of the influence of each stage in the typical characterisitcs of SCH. One hundred eighthy seven VOCs
were identified, being associated to several origins and formation pathways. VOCs formed during stage 1 and 2
were originate from raw material, and its oxidation (i.e. enzymatic browning) and thermal degradation (i.e. lipid
oxidation, Maillard reactions, Strecker degradation). In stage 3 and 4, the caramelization and melanoidin
degradation also occurred, while in stage 5, the thermal degradation continues, followed by microbial activity.
Chemometric analysis allowed to identify 35 VOCs as potential markers for processing control by the producers
and as guarantee of the typicality and authenticity of SCH. Based on the obtained results, we propose for the first
time an innovative schematic diagram explaining the potential reactions and pathways for VOCs formation
during the different steps of the SCH production.info:eu-repo/semantics/publishedVersio
Estudos multitemporais com dados de detecção remota sobre a fronteira da Guiné-Bissau
Este estudo incidiu sobre duas regiões muito importantes no que respeita à definição da fronteira na Guiné-Bissau, Cabo Roxo e Ponta Cajete e tem como objectivo desenvolver estudos multitemporais para definir a posição exacta dos marcos de fronteira, com base em informação geográfica e dados de detecção remota antiga e recente. Foram utilizadas imagens do satélite de alta resolução espacial (WorldView2) de 2013 e 2014. Para melhorar a resolução espacial das imagens e consequentemente beneficiar a interpretação do terreno, foram testados vários algoritmos de fusão das bandas multiespectrais com a pancromática.
O resultado da análise multitemporal permitiu detectar a localização exacta do marco de fronteiro nº 184 e algumas mudanças nas formas de relevo litorais nas duas regiões em estudo
Avaliação do efeito da aplicação de manoproteínas comerciais no incremento da qualidade de vinhos brancos
Face à exigência dos consumidores atuais, as características sensoriais de um vinho, assim como a sua estabilidade, são fatores determinantes para a sua aceitabilidade no mercado. A instabilidade proteica do vinho e consequente desnaturação/precipitação das proteínas depende de fatores
(intrínsecos e extrínsecos) e é responsável pelo aparecimento de turvação nos vinhos brancos. Para
prevenir a instabilidade proteica são usados vários produtos enológicos, com objetivo de remover
as proteínas instáveis, no entanto com várias limitações, tais como eficiência e modificação das características
físico-químicas e sensoriais no vinho.
Nos últimos anos têm surgido diversos aditivos comerciais à base de manoproteínas, já que as mesmas
podem ser uma via alternativa para a estabilização proteica do vinho.
Neste trabalho foram selecionadas onze manoproteínas comerciais para avaliar o seu efeito na estabilização
proteica, bem como o seu efeito na composição fenólica e nas características cromáticas
e sensoriais num vinho branco.
Os resultados obtidos mostraram que 9 das 11 manoproteínas testadas apresentaram efeito positivo
na estabilização proteica do vinho. Além disso, todas as manoproteínas diminuíram o potencial
de acastanhamento dos vinhos, e de um modo geral conduziram a um aumento da luminosidade.
Na análise sensorial, apesar de não haver diferenças significativas relativamente ao vinho controlo,
tendencialmente os vinhos mais pontuados foram os tratados com manoproteínas, nomeadamente
ao nível da diminuição da cor, equilíbrio gustativo e na componente aromática, frutado e floral.
Pelos resultados obtidos neste trabalho, podemos concluir que as manoproteínas parecem ser uma
alternativa eficiente na estabilização proteica de vinhos brancos e que podem simultaneamente melhorar
as características sensoriais do vinho, porém, convém salientar que estes resultados devem
ser encarados como preliminares, sendo necessário realizar mais estudos com outros tipos de vinhos.info:eu-repo/semantics/publishedVersio
Efeito da aplicação de taninos enológicos na evolução das características fenólicas e sensoriais de um vinho tinto
info:eu-repo/semantics/publishedVersio
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