Artigos em revistas internacionais
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- Systematization of the types of adaptations requested in pedestrian routes: human strategies in sport, tourism and other critical situationsPublication . Fernando, Catarina; Fernando, Catarina; Lopes, Hélder; Lopes, Helder; Prudente, João; Prudente, João Filipe; Vicente, AntónioThe aim of this work is to create a structure of knowledge that allows to understand and explain different adaptations requested in pedestrian routes to individuals. We establish the conceptual framework in which this study fits and define its application to two types of frequent adaptations in these activities: uneven terrain and sloped terrain (downhill), establishing which variables to consider and how they interrelate in order to establish decision trees that allow us to make choices and set up strategies consciously and intentionally. We also try to highlight some particularities in the application of these instruments to situations in the field of sport and tourism.
- Evolution of attack in handball when playing 7 vs. 6 with empty goal between 2020 and 2023: coaches’ perception vs. observational resultsPublication . Prudente, João Nunes; Cardoso, Américo Ramos; Rodrigues, Ana José; Mendes, João N.; Fernando, Catarina; Lopes, Hélder; Trejo-Silva, Alejandro; Sousa, Duarte Filipe; Prudente, João Filipe; Ramos Cardoso, Américo; Rodrigues, Ana; Noite Mendes, Joao Manuel; Fernando, Catarina; Lopes, Helder; Sousa, DuarteRecently, several studies on the 7 vs. 6 “empty goal” (EG) in handball have produced different and even contradictory results. The aim of the present study was to investigate the behavior of teams and players in the 7 vs. 6 EG attack in the European (Euro) and World Championships (WCh) between 2020 and 2023 and characterize the coaches’ perceptions.MethodsA mixed-methods approach was used, consisting of the following: (i) an observational methodology and instrument developed and validated to collect observational data on player and team behavior; and (ii) a developed and validated questionnaire to coaches on their perceptions of the 7 vs. 6 game. Observational data were collected during the Euro 2020 and 2022 games (n = 62) and the WCh 2021 and 2023 games (n = 70). A total of 132 games and 391 situations of 7 vs. 6 attacking sequences were observed. In total, 156 coaches participated (146 men), with a mean age 42.33 ± 11.87 years, 19 nationalities, and with 12.77 ± 9.45 years of experience.Results and discussionThe choice of 7 vs. 6 offensive play was mostly made in the second half (>73%). The effectiveness of 7 vs. 6 offensive sequences was higher in the top six teams than in the team's ranked 7th to 12th (Euro 2020 51.6%–50.0%; WCh 2021 52.0%–50.0%; Euro 2022 53.1%–41.7%; WCh 2023 50.0%–43.8%). Some patterns of association were found (p < 0.05 and with values >±1.96): (i) scoring a goal with a breakthrough shot was significantly associated with the effectiveness of the 7 vs. 6 attack (Euro 2020 2.61; WCh 2021 2.87; Euro 2022 2.68; WCh 2023 2.32); (ii) teams in the top six significantly used 7 vs. 6 when they were winning (Euro 2020 2.17; WCh 2021 3.52; Euro 2022 5.88; WCh 2023 2.54); and (iii) teams in the bottom six used it when they were losing by at least four goals (Euro 2020 7.56; Euro 2022 6.64; WCh 2023 4.37) or when they were winning by four goals or more (WCh 2021 2.58). Coaches that agree with the possibility of playing 7 vs. 6 (74.4%), rarely or never do so (55.6%) because it brings little or no advantage (52.6%). The results of the analysis confirmed the perception of the coaches, the low use of 7 vs. 6, the low advantage associated with it, and the influence of the result and the moment of the game on its use.
- Hikes and trails systematization of the types of obstacles/adaptations in pedestrian routesPublication . Fernando, Catarina; Fernando, Catarina; Vicente, António; Lopes, Hélder; Lopes, Helder; Prudente, João; Prudente, João FilipeHikes and trails are increasingly popular activities, in the field of tourism, but also at the level of recreational activities. With this work, we intend to create an integrative vision of the activity that includes the Situation / Context / Individual, which allows the development of instruments in order to enable an intervention, with a functional character, in this type of activities. To this end, we have systematized a set of adaptations requested from individuals, characteristics in the pedestrian paths, using the existing bibliography and an analysis of the obstacles identified in the activities.
- Soluble extracellular polymeric substances and microplastics: exposure-response and circular reuse for removalPublication . Rodrigues, Filipa; Mendonça, Ivana; Faria, Marisa; Gomes, Ricardo; Gómez Pinchetti, Juan L.; Ferreira, Artur; Cordeiro, Nereida; cordeiro, nereidaMicroplastics (MPs) are pervasive in aquatic systems, threatening ecosystems, human health, and microalgal production. Soluble extracellular polymeric substances (S-EPS) can agglomerate particles and aid removal. This study examines S-EPS from the cyanobacterium Cyanocohniella rudolphia (BEA 0786B) to (i) model and optimise S-EPS production, (ii) assess production in water contaminated with polystyrene MPs (PS-MPs), and (iii) test S EPS as a bioflocculant for PS-MPs removal. Response surface methodology (RSM) defined a cost-lean operating window and predicted an optimum S-EPS titre of 113 mg/L at 7 days using 10 g/L nitrogen, 0.98 g/L phosphorus, and a biomass-to-medium ratio of 1:6.87 (w/v). Cultures were challenged with PS-MPs (50 μg/L and 5 mg/L) under static or aerated conditions, and at both exponential and stationary phases, and showed stimulated S-EPS synthesis with increases of up to 34%, depending on hydrodynamics and growth stage. Purified S-EPS were evaluated as a bioflocculant at 2 g/L PS-MPs to probe robustness and rate-limiting mechanisms and to delineate a conservative operating window. Maximum removal of 82% was achieved in freshwater at pH 3.5 with Fe3+ 0.05% (w/w), 25 ◦C, S-EPS dose 400 mg/L (S-EPS:PS-MPs 1:5, w/w), and 60 min flocculation. Zeta potential trends and microscopy support charge neutralisation/bridging as the dominant mechanism. Compatible with standard coagulation/flocculation units, the approach links cost-lean, cultivation-derived S-EPS (typically dis carded) to their reuse as a low-additive pretreatment for algal-cultivation intake waters (freshwater/low salinity), reducing reliance on synthetic coagulants and added salinity/metal-sludge burdens. Overall, C. rudolphia is a promising S-EPS producer, whose production is enhanced by exposure to PS-MPs, and its S-EPS acts as an efficient, bio-based flocculant for PS-MPs. The results support process designs to safeguard microalgal operations and to mitigate microplastic pollution in water. This work integrates RSM-optimised S-EPS produc tion, environmental-level exposure-response, and a high-load removal benchmark, enabling circular, low additive, drop-in pretreatment compatible with standard coagulation/flocculation units.
- Genetic diversity and conservation of the Madeira Island (Portugal) endemic Geranium maderense Yeo (Geraniaceae)Publication . Gouveia, M.; Nyberg, B.; Aedo, C.; Bairos, C.; Sequeira, M. Menezes de; Gouveia, Manuela; Sequeira, MiguelGeranium maderense is a perennial, monocarpic herb, up to 200 cm tall, producing very showy inflorescences, very rare in the wild, although cultivated throughout the world as an ornamental plant. G. maderense is protected under the EC habitats directive (Annex *B-II, IV) and Bern Convention (Annex I) only found, so far, in two cliff associated sites, and classified as a Critically Endangered species (IUCN). Using unmanned aerial vehicle (UAV; drone) technology, two new populations were detected, and a new distribution map is presented. Inter-simple sequence repeat markers were used to detect genetic diversity in natural populations and garden grown plants. Genetic diversity estimates revealed retention of genetic variation and weak genetic structure in G. maderense populations. Cluster and principal component analyses formed coherent groups, indicating that genetic diversity in the studied wild populations of G. maderense is heterogeneously distributed. Our results provide crucial information for the preservation of natural populations of G. maderense, and allow for the revaluation, following IUCN criteria as Endangered (EN).
- Presidential elections and secretary appointment: an event study for us biotechnology and drugsPublication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, Nuno; Martins, António; Albuquerque, Bruno; Sardinha, LuisThe aim of this study is to analyse the effect of the 2024 US presidential election and the appointment of the US health secretary to the largest US listed biotechnology and drug firms. Using an event study methodology, we find that President Donald Trump’s election had no sig nificant impact on the industry. On the contrary, the results show statistically significant negative stock price reactions around the US health secretary appointment. The negative industry reaction to the US health secretary appointment is largely explained by his scepticism about vaccination and criticism about the high prices of drug prescriptions and margins in the industry. These re sults highlight the importance of top government position appointments, especially when such appointments eliminate much of the uncertainty regarding future government action in the in dustry and political uncertainty hypothesis. Finally, cross-section analysis reveals that the firms most penalized by the 2024 US presidential election and the appointment of the US health sec retary are those with the highest investments in R&D and capital expenditures. This could mean lower future investments in new vaccines or drugs, seriously harming society.
- 2024 U.S. presidential elections: an event study for U.S. and non-U.S. fossil fuel and renewable listed firmsPublication . Martins, António Miguel; Albuquerque, Bruno; Sardinha, Luís; Moutinho, Nuno; Martins, António; Albuquerque, Bruno; Sardinha, LuisThis study examines the short-term market effect of Donald Trump’ victory in the 2024 US presidential election on largest US and non-US listed worldwide fuel fossil and renewable firms. Employing an event study meth odology, we observe a negative and statistically significant stock price reaction for worldwide renewable listed firms. An analysis by economic zones reveals the existence of negative abnormal returns for renewable energy firms in the US, Europe, India and in the rest of the world. In the case of China, abnormal returns are not sta tistically significant. With respect to worldwide fossil fuel listed firms, abnormal returns are generally not sta tistically significant. However, regarding US firms, we observe positive and statistically significant abnormal returns. These abnormal returns are explained by the change of US energy policy (pro-oil and gas policy) and the expected cut in subsidies and lower profitability of investments in green energies. Finally, our study provide insight into which firm-specific characteristics emerge as value drives around US presidential elections. The results show that despite the change in environmental policy in the US, favourable to fossil energy, the stock markets reward firms with high environmental ratings. Overall, our results indicate that 2024 US presidential election, for implying a change in US energy policy, has relevant policy implications for energy listed firms.
- Shifting currents: expert perspectives on the adoption of direct current in power gridsPublication . Ngirwa, Catherine; Reis, Diogo; Morais, Hugo; Pereira, Lucas; Ngirwa, CatherineUtilization of renewable energy resources for energy generation brought significant attention to Direct Current (DC) technologies, as many of them produce and store electricity in DC. Compared to Alternating Current, the DC technologies, specifically in Medium-Voltage (MV) and Low-Voltage (LV), are in their infancy, leading to less data availability for decision-making. To inform early-phase technologies, experts are consulted through the structured Expert Elicitation (EE) method, though few have explored it in examining technical and non technical aspects of MVDC and LVDC technologies. Hence, in this paper, we present two EE studies on eleven (11) MVDC and LVDC technologies proposed in the Shift2DC research project — applicable for ports, buildings, industry, and data centers. We found that experts perceived the presented DC technologies as feasible and important. Among the most perceived concerns for DC technologies adoption are a lack of trained personnel, public awareness, and uncertainty in regulations to enforce the use of innovations. Experts proposed the need for educational strategies for the general public and a structured curriculum for training technicians in DC. In addition, experts envisioned enabling emerging technologies, such as digital twins and energy management systems, for DC system management.
- Analysis of the influence of the numerical relation in handball during an organized attack, specifically the tactical behavior of the center backPublication . Prudente, João Nunes; Cardoso, Américo Ramos; Rodrigues, Ana José; Sousa, Duarte Filipe; Prudente, João Filipe; Ramos Cardoso, Américo; Rodrigues, Ana; Sousa, DuarteIn the last decades, observational methodology has been widely used in scientific research in sport, namely in the study of team games like handball, due to its characteristics. Handball, in addition to being a collective, complex, dynamic, and interactive sport, has its own characteristics and demands a performance analysis that takes into account the context and interaction between different factors and variables. The present study analyzes how the different numerical relations in an attack can change the center back’s patterns of tactical behavior. Observational methodology and a mixed ad hoc instrument combining field format and category systems appropriately validated by experts were used. Data were taken from 20 matches involving teams classified in the first four places in the 2017 Men’s World Championship. These were recorded from TV broadcasts, and the total number of offensive sequences carried out in an organized attack game method (n = 990) was analyzed. In each of the sequences carried out in an organized attack, the numerical relation in attack or defense was observed and recorded. In addition to this, it was verified whether the attacking team maintained or replaced the goalkeeper by a field player in the attack. Both sequential analysis techniques with lags, prospective, and retrospective, as well as polar coordinate analysis, were used. Results have shown that there are different behavioral patterns of the center back in the three different situations of numerical relation. Another element that stood out was that in numerical equality with the defense and no goalkeeper at the goal, the center back opted for greater security and less risk of loss of the ball.
- The effectiveness of a tactical games approach in the teaching of invasion gamesPublication . Gouveia, Élvio Rúbio; Gouveia, Bruna; Marques, Adilson; Kliegel, Matthias; Rodrigues, Ana; Prudente, João; Prudente, João Filipe; Rodrigues, Ana; Lopes, Helder; Ihle, AndreasAbstract: Purpose: The main purposes of this study were (a) to assess the effectiveness of the tactical games approach on students’ invasion game performance when compared to the technique-oriented approach, and (b) to investigate whether there was a difference in motor engagement time (MET) between the both pedagogical approaches. Method: The sample consisted of 79 students (13-16 years), allocated to the Intervention Group (IG) following the tactical games protocol, or to the Control Group (CG) following the technique-oriented approach. Psychomotor performance was assessed by the Game Performance Assessment Instrument. MET was assessed by direct observation. Results: Both pedagogical approaches promoted off- and on-the-ball movement over eight consecutive weeks. Comparing the effectiveness of these two teaching approaches, no difference was found. However, collapsed across the two time points, students had better on-the-ball decision-making in the tactical games approach, as well as more MET. Conclusion: Continued replication of this research including long term follow-up is necessary to further strengthen the generalizability of these findings across alternative school contexts.