890 resultados para João V, Rei de Portugal, 1689-1750


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The occurrence of mafic (mainly gabbros and diorites) and felsic (syenites and granites) rocks, in close spatial association, in the Elvas region, at the northern part of the Ossa-Morena Zone, could be interpreted as a single bimodal (alkaline) plutonic complex. However, in spite of scarce isotopic (Sm-Nd) data, the co-magmatic origin of both rock groups (mafic and felsic) has already been questioned [1]. Based on the mineral chemistry of primary clinopyroxenes (Di–Hd, %En: 45.5 – 27.2) and representative whole-rock analyses, gabbros and diorites of the Elvas massif show a transitional character between alkaline and non-alkaline fields and wide compositions: SiO2 (42.47 – 58.00 wt%); TiO2 (0.24 – 1.68 wt%); Y/Nb (4.0 – 10.7); Th (0.1 – 6.8 ppm); Zr (18.6 – 576.9 ppm). The felsic group is composed by highly differentiated rocks which correspond to distinct levels of silica saturation and alkalinity. Peralkaline syenites usually present sodic (riebeckite) and sodic-calcic (aegirine-augite, ferrowinchite) inosilicates and reveal quite variable compositions: SiO2 (57.50 – 72.07 wt%); TiO2 (0.10 – 1.45 wt%); Th (1.7 – 67.0 ppm); Zr (133.0 – 4800.0 ppm). The alkaline granites show hedenbergite as the characteristic inosilicate, presenting relatively common compositions: SiO2 (61.85 – 78.06 wt%); TiO2 (0.21 – 0.58 wt%); Th (11.8 – 38.4 ppm); Zr (317.3 – 1234.6 ppm) [2]. Recent Sm-Nd isotopic results, on a total of 18 whole-rock samples (6 mafites and 12 felsites), allow new and more consistent interpretation concerning the petrogenesis of these plutonic rocks. Assuming an age of 490 Ma [3], the felsic rocks provide (0.6 < Nd490 < 4.3), similar to other contemporary (per)alkaline rocks of this region [4], reflecting magmatic extractions from time-integrated depleted mantle sources followed by variable and incomplete mixing (and/or AFC-type) processes with enriched, probably crustal sources. This alkaline/peralkaline magmatism is thought to represent the main regional record of the rifting event which presumably led to the opening of the Rheic Ocean. On the other hand, the mafic plutonic rocks of the Elvas massif cannot represent the magmatic precursors of these syenites and granites as they show completely distinct Nd isotopic ratios (3.7 < Nd490 < 1.2) indicating important contribution of long-term enriched (crustal) sources. Instead, considering the age and the Nd isotopic signature of other mafic plutonic unit emplaced nearby (the Campo Maior massif: ca. 370 Ma; 6.0 < Nd370 < 5.2) [5], and recalculating the isotopic ratios of the Elvas massif for the same age (4.3 < Nd370 < 1.6), it is plausible to consider that these plutons (Campo Maior and Elvas) can be coeval and representative of the Variscan magmatism in this region. In such hypothesis, the differences between these isotopic values could be explained, on a time-integrated basis, either by magmatic sources for the Elvas massif less enriched in LREE than the sources involved in the Campo Maior massif, or, if both plutonites share similar depleted mantle sources, by magmatic differentiation paths considerably affected by crustal contamination processes, which reached higher degrees in the Campo Maior massif.

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Aim of the study: To introduce and describe FlorNExT®, a free cloud computing application to estimate growth and yield of maritime pine (Pinus pinaster Ait.) even-aged stands in the Northeast of Portugal (NE Portugal). Area of study: NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves) and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal. Material and methods: FlorNExT® implements a dynamic growth and yield modelling framework which integrates transition functions for dominant height (site index curves) and basal area, as well as output functions for tree and stand volume, biomass, and carbon content. Main results: FlorNExT® is freely available from any device with an Internet connection at: http://flornext.esa.ipb.pt/. Research highlights: This application has been designed to make it possible for any stakeholder to easily estimate standing volume, biomass, and carbon content in maritime pine stands from stand data, as well as to estimate growth and yield based on four stand variables: age, density, dominant height, and basal area. FlorNExT® allows planning thinning treatments. FlorNExT® is a fundamental tool to support forest mobilization at local and regional scales in NE Portugal.

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The main aim of the research project "On the Contribution of Schools to Children's Overall Indoor Air Exposure" is to study associations between adverse health effects, namely, allergy, asthma, and respiratory symptoms, and indoor air pollutants to which children are exposed to in primary schools and homes. Specifically, this investigation reports on the design of the study and methods used for data collection within the research project and discusses factors that need to be considered when designing such a study. Further, preliminary findings concerning descriptors of selected characteristics in schools and homes, the study population, and clinical examination are presented. The research project was designed in two phases. In the first phase, 20 public primary schools were selected and a detailed inspection and indoor air quality (IAQ) measurements including volatile organic compounds (VOC), aldehydes, particulate matter (PM2.5, PM10), carbon dioxide (CO2), carbon monoxide (CO), bacteria, fungi, temperature, and relative humidity were conducted. A questionnaire survey of 1600 children of ages 8-9 years was undertaken and a lung function test, exhaled nitric oxide (eNO), and tear film stability testing were performed. The questionnaire focused on children's health and on the environment in their school and homes. One thousand and ninety-nine questionnaires were returned. In the second phase, a subsample of 68 children was enrolled for further studies, including a walk-through inspection and checklist and an extensive set of IAQ measurements in their homes. The acquired data are relevant to assess children's environmental exposures and health status.

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Children spend a large part of their time at schools, which might be reflected as chronic exposure. Ultrafine particles (UFP) are generally associated with a more severe toxicity compared to fine and coarse particles, due to their ability to penetrate cell membranes. In addition, children tend to be more susceptible to UFP-mediated toxicity compared to adults, due to various factors including undeveloped immune and respiratory systems and inhalation rates. Thus, the purpose of this study was to determine indoor UFP number concentrations in Portuguese primary schools. Ultrafine particles were sampled between January and March 2014 in 10 public primary schools (35 classrooms) located in Porto, Portugal. Overall, the average indoor UFP number concentrations were not significantly different from outdoor concentrations (8.69 × 10(3) vs. 9.25 × 10(3) pt/cm(3), respectively; considering 6.5 h of indoor occupancy). Classrooms with distinct characteristics showed different trends of indoor UFP concentrations. The levels of carbon dioxide were negatively correlated with indoor UFP concentrations. Occupational density was significantly and positively correlated with UFP concentrations. Although the obtained results need to be interpreted with caution since there are no guidelines for UFP levels, special attention needs to be given to source control strategies in order to reduce major particle emissions and ensure good indoor air quality.

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A opção por um modelo de organização da formação contínua assenta em pressupostos teóricos e políticos sobre a formação e sobre a profissionalidade docente, mas também sobre a escola e os processosde mudança. Este livro explicita os diferentes modelos de organização da formação contínua de professores, situando-a entre a pessoa-professor e a organização-escola. Perspectivando o aperfeiçoamento profissional e o desenvolvimento organizacional como finalidades da formação contínua, os estudos aqui reunidos evidenciam luzes e sombras do sistema vigente e problematizam a inserção da escola na organização da formação.

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No terceiro capítulo – intitulado Docência e integração na educação básica em Portugal – problematiza-se a relação entre a educação tradicional e a educação democrática visando compreender por que é que, sendo mais adequada a pedagogia da participação para o desenvolvimento global da criança, se continua a manter, nas escolas portuguesas, uma pedagogia suportada pela uniformidade de métodos e programas. Metodologicamente fundamentado nos princípios orientadores relativos à investigação-ação, este capítulo estuda as práticas potenciadoras de uma educação integrada e os contributos da formação em contexto. O discurso dos professores envolvidos no estudo realça a parca formação (inicial e contínua) relativamente à prática de um ensino integrado e participado e salienta a compartimentação disciplinar como fator constrangedor. Afirma também a necessidade de redefinição no trabalho do professor, nomeadamente na autorreflexão das práticas, na partilha dessas práticas com os seus pares e no desenvolvimento profissional ao longo da vida. Constata, porém, que o trabalho de cooperação expressa-se sobretudo na partilha a dois. A análise dos discursos atesta também a hipótese das práticas pedagógicas tenderem mais para uma pedagogia transmissiva do que para uma pedagogia da participação.

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O fogo é um processo frequente nas paisagens do norte de Portugal. Estudos anteriores mostraram que os bosques de azinheira (Quercus rotundifolia) persistem após a passagem do fogo e ajudam a diminuir a sua intensidade e taxa de propagação. Os principais objetivos deste estudo foram compreender e modelar o efeito dos bosques de azinheira no comportamento do fogo ao nível da paisagem da bacia superior do rio Sabor, localizado no nordeste de Portugal. O impacto dos bosques de azinheira no comportamento do fogo foi testado em termos de área e configuração de acordo com cenários que simulam a possível distribuição destas unidades de vegetação na paisagem, considerando uma percentagem de ocupação da azinheira de 2.2% (Low), 18.1% (Moderate), 26.0% (High), e 39.8% (Rivers). Estes cenários tiveram como principal objetivo testar 1) o papel dos bosques de azinheira no comportamento do fogo e 2) de que forma a configuração das manchas de azinheira podem ajudar a diminuir a intensidade da linha de fogo e área ardida. Na modelação do comportamento do fogo foi usado o modelo FlamMap para simular a intensidade de linha do fogo e taxa de propagação do fogo com base em modelos de combustível associados a cada ocupação e uso do solo presente na área de estudo, e também com base em fatores topográficos (altitude, declive e orientação da encosta) e climáticos (humidade e velocidade do vento). Foram ainda usados dois modelos de combustível para a ocupação de azinheira (áreas interiores e de bordadura), desenvolvidos com base em dados reais obtidos na região. Usou-se o software FRAGSATS para a análise dos padrões espaciais das classes de intensidade de linha do fogo, usando-se as métricas Class Area (CA), Number of Patches (NP) e Large Patches Index (LPI). Os resultados obtidos indicaram que a intensidade da linha de fogo e a taxa de propagação do fogo variou entre cenários e entre modelos de combustível para o azinhal. A intensidade média da linha de fogo e a taxa média de propagação do fogo decresceu à medida que a percentagem de área de bosques de azinheira aumentou na paisagem. Também foi observado que as métricas CA, NP e LPI variaram entre cenários e modelos de combustível para o azinhal, decrescendo quando a percentagem de área de bosques de azinheira aumentou. Este estudo permitiu concluir que a variação da percentagem de ocupação e configuração espacial dos bosques de azinheira influenciam o comportamento do fogo, reduzindo, em termos médios, a intensidade da linha de fogo e a taxa de propagação, sugerindo que os bosques de azinhal podem ser usados como medidas silvícolas preventivas para diminuir o risco de incêndio nesta região.

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Introduction: Mental health has an imperative roll in general health, and it’s known that most mental and physical diseases are influenced by a combination of biological, psychological and social factors, in which takes place the Internet addiction. Objectives: identify the sociodemographic variables that influence the mental health of college students; identify academic variables that influence the mental health of college student. Methods: Quantitative, descriptive-analytical and cross-sectional study with 511 college students of the Central Region of Portugal. It was used a questionnaire on sociodemographic and academic context, and were used the following scales: Mental Health Scale – PhD José Luís Pais Ribeiro (2011); Internet Addiction Test, Portuguese version by Pontes e Patrão (2013). Results: Mostly female students, standing largely in the age group of 17-21 years, living in urban areas, with an average family income. Younger students have high addition to the internet (62.2%). Sex interfere with the mental health of students. The lower the negative impact of adding Internet emotions / feelings and lower its negative impact on daily life, the less anxiety, depression and loss of emotional / behavioral control of college students. The negative impact on daily life establishes a direct relationship with the positive affect, indicating that the greater the negative impact, less positive affect students. Conclusions: The results obtained point to the need to implement mental health programs, by conducting two workshops, promoting social interaction among students, to help them find more effective ways to respond to the daily challenges.

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Repeat photography is an efficient, effective and useful method to identify trends of changes in the landscapes. It was used to illustrate long-term changes occurring in the landscapes. In the Northeast of Portugal, landscapes changes is currently driven mostly by agriculture abandonment and agriculture and energy policy. However, there is a need to monitoring changes in the region using a multitemporal and multiscale approach. This project aimed to establish an online repository of oblique digital photography from the region to be used to register the condition of the landscape as recorded in historical and contemporary photography over time as well as to support qualitative and quantitative assessment of change in the landscape using repeat photography techniques and methods. It involved the development of a relational database and a series of web-based services using PHP: Hypertext Preprocessor language, and the development of an interface, with Joomla, of pictures uploading and downloading by users. The repository will make possible to upload, store, search by location, theme, or date, display, and download pictures for Northeastern Portugal. The website service is devoted to help researchers to obtain quickly the photographs needed to apply RP through a developed search engine. It can be accessed at: http://esa.ipb.pt/digitalandscape/.

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The demand for natural sweeteners has been gaining more and more importance due to the great controversy associated with the use of some synthetic sweeteners as cyclamates, aspartame and acesulfame-K. The steviol glycosides (E 960) are a group of natural sweeteners of generalized use; these compounds are obtained from Stevia rebaudiana Bertoni, a sweet plant native from South America (Carocho et al., 2015). However, Stevia rebaudiana Bertoni may have other uses to be exploited, in particular due to its antioxidant capacity. This plant is already produced in Portugal but it is important to evaluate if the plant chemical composition is maintained regardless of culture conditions. Therefore, in this study, stevia samples were cultivated in Braganca (northeastern of Portugal) in a field trial with defined culture conditions. After harvesting, the plants were submitted to two different treatments: kept fresh by freezing (-20°C) and oven-dried (30°C). The antioxidant profile of the samples was studied through evaluation of free radicals scavenging activity, reducing power, phenolic compounds (HPLC-DAD-ESI/MS), tocopherols (HPLC-fluorescence) and free sugars (HPLC-RI). Significant differences were observed: while oven-dried samples showed the highest antioxidant activity and phenolic compounds concentration (mainly 5-O-caffeoylquinic acid and 3,5-O-dicaffeoylquinic acid), the frozen fresh samples had the highest values of total tocopherols and total sugars. These results confirm that the plants grown in Bragança have excellent bioactive secondary metabolites responsible for the observed antioxidant capacity.

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Ao longo de todo o séc. XX, o jazz construiu um espaço alternativo às dicotomias heurísticas tradicionais, como por ex. tradição/inovação, erudito/popular, composição/improvisação, entre outras. Por entre discursos polarizados, o jazz afirmou-se como domínio musical conciliador de diferenças culturais e sociais, configurando um espaço novo de mediação, um “jazz art world” como definido pelo sociólogo Paul Lopes. Nesse espaço, a individualidade sempre assumiu enorme centralidade, em virtude do papel particularmente criativo do performer e também da sua relação elástica com os «modelos» referenciais para a performance. Assim, o jazz afigura-se um domínio privilegiado para a expressão da individualidade e, por conseguinte, para a construção e identificação de uma «identidade musical», tal como a expressão é proposta nesta tese. Para a discussão destes problemas conceptuais, esta tese recorre, como estudos de caso, a um conjunto de pianistas portugueses: António Pinho Vargas (1951-), Mário Laginha (1960-), João Paulo Esteves da Silva (1961-) e Bernardo Sassetti (1970-2012). É traçada a sua trajectória pessoal e formativa, e é apresentada uma análise da sua produção musical, com recurso à «teoria das tópicas» enquanto modelo particularmente orientado para a análise da música popular. No sentido de compreender os processos de construção das identidades musicais destes pianistas, são ainda abordadas outras temáticas, como a própria definição de «jazz», o jazz enquanto música dialógica, ou os fluxos diaspóricos do jazz (incluindo as respectivas implicações e variantes terminológicas, como “jazz diaspora”, “musical cosmopolitanism” e “glocalization”). Recorrendo a pesquisa bibliográfica, trabalho de campo (mormente a entrevista) e técnicas de análise musical, esta tese realiza uma exploração aprofundada destes tópicos e do trabalho dos músicos em particular. Desta forma, pretende oferecer um contributo para uma reflexão conceptual sobre o jazz em geral no âmbito dos jazz studies, e também para um mapeamento estilístico e identitário do jazz em Portugal.

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O presente trabalho consiste num estudo sobre a evolução do ensino da Bateria em Portugal e toda a sua envolvência ─ músicos e principais instituições com tradição e responsabilidade no ensino e divulgação musical; Abstract: This dissertation proposes a study on the evolution of the teaching of the Drum Set in Portugal and all its surroundings ─ musicians and leading institutions with tradition and responsibility in teaching and musical dissemination.

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The Asteraceae family is spread worldwide. In Portugal, there are more than 300 species, standing out as one of the botanical families with largest representation in the Portuguese flora. Coleostephus myconis (L.) Rchb.f. is a scarcely studied Asteraceae species, characterized as having ruderal growth and persistence in abandoned soils (an expanding problem due to the desertification phenomena in rural areas). In this work, the flowers of C. myconis were collected in three different flowering stages (i: flower bud; ii: flower in anthesis; iii: senescent flower) from the Northwestern area of the Portuguese territory. Powdered samples (1 g) were extracted twice with ethanol:water 50:50 (v/v). After removing solvents, the combined extracts were re-dissolved, filtered through 0.22-μm disposable LC filter disks and analyzed by high performance liquid chromatography coupled to a diode array detector and electrospray ionization-mass spectrometry (HPLC-DAD/ESI-MS). The phenolic compounds were characterized according to their UV and mass spectra, and retention times. For the quantitative analysis, calibration curves of standard compounds were used. According to the UV spectra (λmax = 314-330 nm) and pseudomolecular ions ([M-H]-) at m/z 353 and 515, all producing an m/z 191 ion, four compounds derived from quinic acid were detected: 3-O-caffeoylquinic acid (Figure 1A), 5-O-caffeoylquinic acid (Figure 1B), 3,5-O-dicaffeoylquinic acid (Figure 1C) and 4,5-O-dicaffeoylquinic acid (Figure 1D), as also supported by the literature [1,2]. A fifth phenolic acid was identified as protocatechuic acid. The detected flavonoid were quercetin-O-glucuronide, quercetin-3-Oglucoside, myricetin-O-methyl-hexoside and a second glycosylated myricetin (not possible to identify completely). Some statistically significant changes were detected among the different assayed flowering stages; nevertheless, 3,5-O-dicaffeoylquinic acid was the major compound, independently of the phenologic stage. According to the previous results, C. myconis might be considered as a potential natural source of these valuable bioactive compounds, especially considering the high botanical representativeness of this plant and its inexpensiveness.

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Separata da "Revista Guimarães", Vol. 90 de 1981. 1ª parte

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Os autores procedem à análise das pastas cerâmicas de 24 amostras de número de recipientes, do povoado calcolítico do Monte da Tumba, recorrendo ao microscópio petrográfico. Esta metodologia revelou-se muito eficaz e permitiu atingir conclusões importantes nos domínios da tecnologia e da análise do site-catchement. De sublinhar a constatação de que as dimensões dos elementos não plásticos das pastas argilosas não parecem relacionar-se com as dimensões nem com a espessura das paredes dos recipientes, mas com o grau de resistência e porosidade pretendidos. Registe-se igualmente que as produções cerâmicas utilizaram matérias-primas locais, num raio de distância mínimo de 750m a partir do povoado.