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- Schreier split extensions of preordered monoidsPublication . Martins-Ferreira, N.; Sobral, M.Properties of preordered monoids are investigated and important subclasses of such structures are studied. The corresponding full subcategories are related between them by appropriate functors as well as with the categories of preordered sets and of monoids. Schreier split extensions are described in the full subcategory of preordered monoids whose preorder is determined by the corresponding positive cone.
- On the Path of Sustainability in Wastewater Treatment: The Golden Mean Applied to Regional ContextPublication . Santos, E.An important part of the environmental degradation is caused by the discharge of untreated or mistreated wastewater. Since centralized treatment systems have proved to be inefficient, tackling the environmental issues requires a regional approach. Wastewater treatment plants (WWTPs) mitigate environmental impacts and contribute to financial savings of other firms. However, the literature evaluating WWTPs’ financial performance and economic sustainability does not abound. Thus, this paper analyses the economic sustainability of wastewater treatment companies in Portugal by NUTS II regions, in 2016-2019. Using firms’ financial reports from SABI, results show that, by and large, firms in the Centre region display higher financial performances when compared to other regions. These results can be used to investigate whether firms in the central region are implementing the best practices regarding management and technology. Results can also foster enhancements in the governance of regulated utilities.
- A Importância da Carta dos Direitos Fundamentais da União Europeia na Construção de um Espaço Unificado de Direitos HumanosPublication . Monteiro, Susana SardinhaOs direitos humanos são, indubitavelmente, uma “ideia nova” que, após o fim da II Guerra Mundial, encontrou o momento propício para a sua efetiva concretização, mediante a adoção de alguns textos internacionais fundamentais, de cariz universal, como a Declaração Universal dos Direitos Humanos, em 1948 e, de cariz regional, como a Convenção Europeia dos Direitos do Homem, em 1950. Os direitos humanos constituem um símbolo universal, ou pelo menos um símbolo para o mundo ocidental. De tal forma que os direitos humanos (civis, políticos, económicos, sociais e culturais), assim como as liberdades fundamentais que se encontram, hoje, consagradas nas Constituições da maior parte dos Estados, bem como nos diversos instrumentos jurídicos internacionais (Cartas, Convenções, Declarações, Pactos e Protocolos Internacionais) não são mais do que o reflexo das vicissitudes e contingências da evolução histórica da humanidade. São o resultado da luta e conquista do homem por um conjunto de valores e princípios hoje considerados essenciais aos olhos dos cidadãos do seculo XXI. Valores e princípios como a dignidade, a liberdade, a igualdade, a solidariedade, a responsabilidade e a universalidade.
- O jogo educacional Multipli enquAnto atividade lúdica e de aprendizagem matemáticaPublication . Sebastião, Fernando; Tavares, Dina; Menino, Hugo Lopes; Oliveira, Eunice; Féria, Ana la; Teixeira, RitaJogar é uma atividade lúdica que proporciona situações de prazer e de descontração, motivando o envolvimento e a atenção das crianças, o que pode ser um fator decisivo para aprender matemática, de forma significativa (Grando, 2000). Para Ponte (2005), o jogo é um tipo de tarefa que deve integrar a experiência matemática das crianças, cabendo ao professor selecionar os jogos a explorar, de acordo com objetivos curriculares a atingir. Do ponto de vista da investigação afigura-se importante proceder à avaliação de jogos educacionais, contribuindo para a melhoria da qualidade desses recursos (Savi et al., 2010). Em relação à dinamização dos jogos, diversos estudos evidenciam que a participação dos alunos em competições matemáticas, de natureza inclusiva, promove a autoconfiança, o autoconceito e a motivação do aluno para aprender matemática (Amado, Carreira & Ferreira, 2016; Tavares & Pinto, 2019). Este estudo pretende avaliar o jogo educacional Multipli, enquanto recurso educativo, e descrever a perceção de crianças relativamente à sua experiência de jogo, no contexto de um campeonato nacional online. Adota-se o modelo ARCS (Dempsey & Johnson, 1998) para analisar a motivação dos alunos na aprendizagem, com base em quatro categorias: atenção, relevância, confiança e satisfação. Consideram-se também categorias relacionadas com a experiência do utilizador, amplamente utilizadas noutros modelos de avaliação de jogos: imersão, habilidade, divertimento, desafio, interação social e aprendizagem (Savi et al. 2010). O estudo desenvolvido é observacional, de natureza descritiva (Bogdan & Biklen, 1994; McMillan & Schumacher, 2005). O instrumento de recolha de dados é o inquérito por questionário, aplicado a crianças do 3.º, 4.º, 5.º e 6.º anos de escolaridade, que permite recolher a informação avaliada sob a forma de afirmações, segundo uma escala de concordância. É espectável que este estudo contribua para a compreensão e utilização dos jogos ao nível pedagógico enquanto tarefa para a aprendizagem da matemática.
- Higher Physical Activity Levels May Help Buffer the Negative Psychological Consequences of Coronavirus Disease 2019 PandemicPublication . Antunes, Raul; Goncalves-Rebelo, Ricardo; Amaro, Nuno; Salvador, Rogério; Matos, Rui; Morouço, Pedro; Frontini, RobertaThis study explored the associations between physical activity (PA) anxiety levels, and the perception of satisfaction of basic psychological needs (BPN), during Coronavirus Disease 2019 (COVID-19) lockdown. Thus, 1,404 participants (977 women, 426 men, and one respondent preferred not to answer) ranging from 18 to 89 years old (36.4 ± 11.7 year-old) completed a questionnaire in the period between 1st and 15th April 2020. The survey included sociodemographic data and the following validated instruments: the International Physical Activity Questionnaire (IPAQ), the Basic Need General Satisfaction Scale and the State-Trait Anxiety Inventory. The Kruskal-Wallis test was performed to examine variation in anxiety levels and BPN satisfaction according to PA category (low, moderate, and high). Spearman’s Rho correlations coefficients were used to determine the association between anxiety levels and psychological needs. Individuals presenting a higher level of PA revealed lower levels of anxiety-state (H = 20.14; p < 0.01). Differences between elements from different levels of PA were found for the autonomy (H = 23.52; p < 0.001), competence (H = 18.89; p < 0.001), and relatedness (H = 24.42; p < 0.001) psychological needs, suggesting that those who feel their BPN as more satisfied have higher levels of PA. The study found statistically significant correlations between anxiety-state and the satisfaction of the needs for autonomy (p = 0.01; r = −0.46), competence (p = 0.01; r = −0.40), and relatedness (p = 0.01; r = −0.21). These findings support the importance that PA has in the anxiety levels during social isolation, emphasizing the importance of multidisciplinary teams in an individual-based approach.
- Differences between Portuguese and Brazilian Patients with Fibromyalgia Syndrome: Exploring the Associations across Age, Time of Diagnosis, and Fatigue-Related SymptomsPublication . Alvarez, Marcos; Albuquerque, Maria Luiza L.; Neiva, Henrique P.; Cid, Luis; Rodrigues, Filipe; Teixeira, Diogo S.; Monteiro, DiogoThe aim of the study was to explore the differences between Brazilian and Portuguese patients with fibromyalgia (FM) syndrome in their experience of fatigue, and to measure differences in the perception of fatigue as a function of age and duration of the diagnosis. In total, 209 Portuguese women aged between 21 and 75 years (M = 47.44; SD = 10.73) and 429 Brazilian women aged between 18 and 77 years (M = 46.51; SD = 9.24) were recruited to participate in the present study. Participants completed the Multidimensional Daily Diary of Fatigue-Fibromyalgia-17 items (MDF-Fibro-17), a specific tool to measure the level of five components of FM-related fatigue. Results showed greater perception of all the components of fatigue in the Brazilian sample. No significant differences were found related to age and duration of FM diagnosis. The multifaceted nature of FM and cultural differences suggests that individualized treatment programs may be necessary to reduce fatigue-related symptoms in patients with this syndrome.
- Could tDCS Be a Potential Performance-Enhancing Tool for Acute Neurocognitive Modulation in eSports? A Perspective ReviewPublication . Machado, Sergio; Travassos, Bruno; Teixeira, Diogo S.; Rodrigues, Filipe; Cid, Luis; Monteiro, DiogoCompetitive sports involve physical and cognitive skills. In traditional sports, there is a greater dependence on the development and performance of both motor and cognitive skills, unlike electronic sports (eSports), which depend much more on neurocognitive skills for success. However, little is known about neurocognitive functions and effective strategies designed to develop and optimize neurocognitive performance in eSports athletes. One such strategy is transcranial direct current stimulation (tDCS), characterized as a weak electric current applied on the scalp to induce prolonged changes in cortical excitability. Therefore, our objective is to propose anodal (a)-tDCS as a performance-enhancing tool for neurocognitive functions in eSports. In this manuscript, we discussed the neurocognitive processes that underlie exceptionally skilled performances in eSports and how tDCS could be used for acute modulation of these processes in eSports. Based on the results from tDCS studies in healthy people, professional athletes, and video game players, it seems that tDCS is applied over the left dorsolateral prefrontal cortex (DLPFC) as a potential performance-enhancing tool for neurocognition in eSports.
- Recovery and evaluation of cellulose from agroindustrial residues of corn, grape, pomegranate, strawberry-tree fruit and favaPublication . Vallejo, Mariana; Cordeiro, Rachel; Dias, Paulo A. N.; Moura, Carla; Henriques, Maria; Seabra, Inês J.; Malça, C.; Morouço, PedroConsidering the expected increasing demand for cellulose fbers in the near future and that its major source is wood pulp, alternative sources such as vegetable wastes from agricultural activities and agro-food industries are currently being sought to prevent deforestation. In the present study, cellulose was successfully isolated from six agroindustrial residues: corncob, corn husk, grape stalk, pomegranate peel, marc of strawberry-tree fruit and fava pod. Cellulose fb ers were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analysis, stereomicroscopy and scanning electron microscopy (SEM). Despite the evident morphological diferences among the extracted celluloses, results revealed similar compositional and thermal properties with the wood-derived commercial microcrystalline cellulose used as a control. Trace amounts of lignin or hemicellulose were detected in all cellulose samples, with the exception of corncob cellulose, that exhibited the greatest extraction yield (26%) and morphological similarities to wood-derived microcrystalline cellulose, visible through SEM. Furthermore, corncob cellulose was found to have ther mal properties (TOnset of 307.17 °C, TD of 330.31 °C, and ΔH of 306.04 kJ/kg) suitable for biomedical applications
- Polymer-Clay Nanocomposites: Exfoliation and Intercalation of Organophilic Montmorillonite Nanofillers in Styrene–Limonene CopolymerPublication . Derdar, Hodhaifa; Meghabar, Rachid; Benachour, Mohamed; Mitchell, Geoffrey; Bachari, Khaldoun; Belbachir, Mohammed; Cherifi, Zakaria; Baghdadli, Mohammed Chakib; Harrane, AmineNanocomposites from Styrene-Limonene copolymers and Algerian organophilic-clay named Maghnite-CTA+ (Mag-CTA+), were prepared by in-situ polymerization using different amounts (2, 5, and 10% by weight) of clay and Azobisisobutyronitrile (AIBN) as a catalyst. The Mag-CTA+ is an organophilic silicate clay prepared through a direct exchange process, using Cetyltrimethylammonuim bromide (CTAB) in which it used as green nano-filler. The preparation method of nanocomposites was studied in order to determine and improve structural, morphological and thermal properties of Sty-Lim copolymer. The struc ture and morphology of the obtained nanocomposites (Sty-Lim/Mag) were determined using Fourier trans form infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM). The analyses confirmed the chemical modification of clay layers and the intercalation of Sty-Lim copolymer within the organophilic clay sheets. Exfoliated structure was obtained for the lower amount of clay (2 wt %), while intercalated structures were detected for higher amounts of clay (5 and 10 wt %). The thermal properties of the obtained nanocomposites were studied by thermogravimetric analysis (TGA) and show a significant improvement in the thermal stability compared with the pure copolymer. The obtained nanocomposites show an optimal degradation temperature of 320°C.
- Home-Advantage during COVID-19: An Analysis in Portuguese Football LeaguePublication . Matos, Rui; Monteiro, Diogo; Antunes, Raul; Mendes, Diogo; Botas, João; Clemente, João; Amaro, NunoCovid-19 pandemic forced, at the final rounds of 2019–2020 season, in many different sports leagues worldwide, teams to play without an audience. Therefore, the present paper aims to compare the home advantage score in the last ten rounds in the 2019–2020 season with the first 24 rounds in the same season using Pollard’s (1986) and Matos et al.’s (2020) methods. In addition, comparisons across different seasons (2016–2017; 2017–2018; 2018–2019 and 2019–2020) using the same methods were also analyzed. Results showed no differences (p > 0.05) between first 24 rounds and the last 10 in 2019–2020 season as well as in the 3 previous seasons. With Pollard’s method, no differences (p > 0.05) were also found among those four seasons on global (all 34 rounds) home advantage. However, a significance difference between 2017–2018 and 2019–2020 (p < 0.05) was founded using Matos et al.’s (2020) method, which is an indicator of the importance of using complementary methods when analyzing the same realities. Overall, despite what might be expectable from recent findings, the lack of an audience in the last 10 rounds of Portuguese Football League 2019–2020 season, due to COVID-19 pandemic, did not affect home advantage. Therefore, future studies could try to analyze other different variables in Portuguese Football League, such as referees’ behaviors, rules changing (e.g., the possibility of making five substitutions, instead of three), crowd dimension and density as well as include variables about odds as forecasts in football being played without crowds.