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- Students' Engagement in School : A literature review.Publication . Veiga, Feliciano Henriques; Galvão, Diana; Almeida, Ana; Carvalho, Carolina; Janeiro, Isabel; Nogueira, João; Conboy, Joseph; Melo, Madalena; Taveira, M. Céu; Festas, M. I.; Bahia, Sara; Caldeira, Suzana Nunes; Pereira, TiagoStudents’ Engagement in School has been the focus of debate concerning academic success and school dropout, and pointed out as a mean to address the problems affecting our schools and their students, not only for having value in itself, but also for being an important mediator between several academic variables. This paper reviews the research and literature on this concept and its relations with personal and contextual variables, as well as with academic performance, with the aim of summarizing the main relationships found. Literature presents a significant number of studies which sustain that personal variables, such as self-efficacy and self-concept, as well as contextual - peers, school, family- are related with school engagement. The adoption of mastery goals, for instance, has a positive impact on school, as they are related with the use of cognitive and self-regulatory strategies by students. Positive relationships with peers, teachers support and the quality of family relations are associated with higher levels of engagement and academic performance, while negative experiences, such as bullying, are related with educational difficulties. Following this, we reflect about the relevance of studying engagement in school, in the context of widespread financial crisis, and emphasize the need to rethink educational institutions considering the paradigmatic changes that currently occur.
- The efficiency of matching in Portuguese public employment servicePublication . Agovino, Massimiliano; Menezes, António Gomes de; Sciulli, DarioThis paper assesses the matching efficiency of the Portuguese public employment service (PES), applying data envelopment analysis (DEA) combined with principal component analysis (PCA) to Portuguese administrative data and comparing the situations in June 1998 and June 2001. We find evidence that the Portuguese public employment service increased its efficiency potential from 0.54 (June 1998) to 0.65 (June 2001), becoming more efficient and more homogenous. However, employment-centres differ in efficiency and factors affecting efficiency diverge among employment-centres. Policies aimed at improving the efficiency of the matching process should be employment-centre specific. Indeed, we find that some employment-centres could benefit from investing in labour market policies, some from investing in social policies, and others from investing in income support policies. Finally, some employment-centres could benefit from a mix of these socio-economic policies.
- Portuguese Adaptation of Students' Engagement in Schools International Scale (SESIS)Publication . Veiga, Feliciano Henriques; Bahia, Sara; Nogueira, João; Melo, Madalena; Caldeira, Suzana Nunes; Festas, Isabel; Taveira, Céu; Galvão, Diana; Janeiro, Isabel; Conboy, Joseph; Carvalho, Célia; Almeida, Ana; Pereira, TiagoContext: The importance of student’s engagement has been recently pointed out in research. However, there has been a lack of engagement assessment instrument, pertaining psychometric qualities. Objective: This paper presents the Portuguese adaptation of the “Student’s Engagement in School International Scale” (SESIS), drawn up from a12 countries international study (Lam et al., 2012; Lam et al., in press). Method: Psychometric properties of this scale were examined with data from 685 students from different grades (6th, 7th, 9th and 10th), from both sexes, and different regions of the country. Results: Factorial analysis of the results, with varimax rotation, lead to three different factors which explain 50.88% of the variance. The scale integrates the original 33 items, and cognitive, affective and behavioural dimensions. For the external validity study, the relationship between student’s engagement in school results and other school variables — academic performance, self-concept — was considered, and significant relations were observed, as expected. Conclusion: The data presented highlights the qualities of SESIS, as well as its usefulness for research purposes. Suggestion: It is suggested the investigation of the extension of SESIS’s three-dimensionality, in future studiesKeywords: Innovation, technology, research projects, etc.
- Compounds identified on hexane and dichloromethane extracts of Salicornia ramosissimaPublication . Isca, Vera M. S.; Seca, Ana M. L.; Pinto, Diana C. G. A.; Silva, Artur M. S.; Silva, HelenaSalicornia ramosissima J. Woods (common purple glasswort) is an annual halophyte, widely distributed in the salt marsh of Ria de Aveiro (Portugal), that belongs to the Salicornia L. genus (Chenopodiaceae).[4] Although phytochemical studies genus on this genus report the presence of compounds which are well-recognized for their biological activities, such as flavonoids, chromones and alkaloids,[3] too little is known about secondary metabolites on purple glasswort. In our previous work we were able to isolate and identify ethyl o-hydroxycinnamate, (E)-fatty alcohol ferulic acid and scopoletin from the dichloromethane extract of S. ramosissima aerial parts. The structure and spectroscopic characterization of some secondary metabolites isolated from dichloromethane crude extract also will be presented and discussed.
- Dinâmica demográfica, educação, emprego e desigualdades sociais nos Açores: 2014 a 2020: Relatório finalPublication . Rocha, Gilberta Pavão Nunes; Palos, Ana Cristina; Diogo, Fernando; Tomás, Licínio Manuel Vicente; Santos, Sérgio
- Bioactive meroditerpenes from Cystoseira abies-marina, collected from the coast of S. Miguel islandPublication . Gouveia, Vera L. M.; Seca, Ana M. L.; Barreto, Maria do Carmo; Silva, Artur M. S.; Kijjoa, AnakeMany substances isolated from marine organisms have demonstrated to possess interesting biological and pharmacological activities and have been used as leads in the development of new pharmaceutical agents. Marine macroalgae are abundant and structuring organisms of the coastal area of all the islands in the Azores Archipelago; some have a markedly seasonal pattern and others are perennial and present during the whole year in the Azorean coasts. One of these is Cystoseira abies-marina which grows abundantly in the coast of the Azores archipelago. Interestingly, it was observed in situ that this alga was not attacked by common predators, such as marine gastropods which led to the suggestion that the great resistance to predation of this species was due to the presence of potentially active compounds, such as antifeedant and/or cytotoxic. Preliminary study on the extracts of Cystoseira abies-marina, collected in S. Miguel Island, showed very promising results for antitumour and antioxidant activities [3]. These results have increased our interest in this alga and led to its phytochemical study. Recently, we have reported the isolation and identification of benzoic acid and two new meronorsesquiterpenes [Cystoazores A (1) and Cystoazores B (2)] from the extracts of this marine alga [4]. Further investigation of this species led to isolation of other two new meroditerpene derivatives (3 and 4). We report here the isolation of the compounds 3 and 4, from Cystoseira abies-marina whose structures were established by 1D and 2D NMR spectral analysis as well as by MS. Additionally, the cytotoxic, anti-inflammatory and antioxidant activities of compounds 1-4 were evaluated and the results will be presented.
- Protein-ligand docking study: diterpenes from Juniperus brevifolia as anticancer and antimicrobial agentesPublication . Sousa, Inês J.; Fernandes, Miguel X.; Seca, Ana M. L.From leaves of Juniperus brevifolia, an endemic conifer from Azores, were isolated and structurally characterized, several dehydroabietane and sandaracopimarane derivatives. Some of them (1-4), displayed antiproliferative activity against cancer cell lines (HeLa, A-549 and MCF-7) and bactericidal effect against Bacillus cereus at different concentrations tested. However, it is not known how these compounds interact with most often proteins involved in the antimicrobial and cytotoxic mechanisms. Protein-ligand docking is mainly used to predict (energy and conformation wise) how small molecules bind to a protein of known 3D structure and to predict possible molecular targets for a set of compounds. In this work, the docking studies were performed, using the FlexScreen program, in order to pick molecular targets from a large set of common anticancer (63) and antimicrobial (39) targets to the selected compounds 1-4. The predicted interactions established between the compounds under study and the anticancer targets revealed that the compounds 1 and 3 interact preferentially with phosphatidylinositol-3,4,5-trisphosphate 5-phosphatase 2, whereas compounds 2 and 4 interact preferentially with human mitochondrial peptide deformylase and -tubulin, respectively. Studying the interactions between the compounds 1 and 3 and the antimicrobial targets we predict that these compounds interact preferentially with RNA polymerase and peptide deformylase. These results provide additional understanding of the cytotoxic and antimicrobial effects of diterpenes studied. These preliminary computational docking predictions of therapeutic targets were established working with just 4 compounds, and to obtain more reliable predictions the number of compounds needs to be increased.
- Synthesis and antioxidant activity of new xanthone-type compoundsPublication . Leal, Stephanie B.; Pinto, Diana C. G. A.; Seca, Ana M. L.; Silva, Artur M. S.; Cavaleiro, José A. S.Owing to our continuing interest in the synthesis of novel oxygen heterocycles we have recently developed a unique synthetic procedure towards the synthesis of new xanthenodiones (2)[5] and extend the work to their aromatization into xanthones (3). Our aim was also to obtain new derivatives with potential biological activities, therefore their ability to scavenge the DPPH radical and to reduce iron(III) were also evaluated. In the present communication we will present and discussed our last results on the synthetic and potential application of xanthones (3).
- Chemical and biological studies from an Azorean macroalga: Ulva rigidaPublication . Silva, Madalena; Vieira, Luís M. M.; Almeida, Ana Paula; Silva, Artur M. S.; Kijjoa, Anake; Seca, Ana M. L.; Barreto, Maria do CarmoNew drugs from natural sources have been targets of the drug discovery program and some bioactive compounds from macroalgae such as sulfated polysaccharides, steroids and diterpens have found their applications in the pharmaceutical industry.[1,2] Consequently, we have investigated the chemical composition and the in vitro antitumor potential of the metabolites isolated from the macroalga Ulva rigida, collected from the Azorean coast, an environmentally healthy habitat with a high level of biodiversity. We hereby describe isolation of isofucosterol (1) and 7(E)-3ẞ-hidroxy-5α, 6α-epoxymegastigmane (2) from the methanol extract of Ulva rigida, collected in May of 2011 in the Sea of St Miguel Island - Azores archipelago. The process of isolation of these metabolites involved chlorophylls elimination by the method previously described[3] and fractionation by column chromatography. The structures of 1 and 2 were established by 1D and 2D NMR spectral analysis and specific rotation as well as comparison of their spectral data with those described in the literature.[4,5] Compounds 1 and 2 were evaluated for their capacity to inhibit the in vitro growth of three human cancer cell lines: MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer) and A375-C5 (human skin cell line), using the protein binding dye SRB method. The results showed that compound 1 exhibited only a weak activity against MCF-7 (GI50 = 122.2 ± 17.9 μM), NCI-H460 (GI50 = 128.4 ± 32.4 μM), A375-C5 (GI50 = 119.2 ± 28.9 μM), while compound 2 was inactive against all the three cell lines (GI50 >200 μM).
- Introducing random investment in high speed rail transport valuationPublication . Couto, Gualter; Nunes, Cláudia; Pimentel, PedroIn this paper, we extend Couto et al. (2012) high-speed rail (HSR) transport valuation model based on real options analysis, in order to embrace random investment. Optimal timing to invest, value of the option to defer and investment opportunity value are assessed considering uncertainty upon HSR demand and investment expenditures, both following a geometric Brownian motion with jumps driven by Poisson processes. Numerical results presented, showing the consistence with the former model and the additional uncertainty impact.
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