FCT2-Artigos (em revistas ou actas indexadas)
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- Ontology-based BIM-AMS integration in European highwaysPublication . Antunes, António Lorvão; Barateiro, José; Marecos, Vânia; Petrović, Jelena; Cardoso, ElsaBIM tools enable decision-making during the lifecycle of engineering structures, such as bridges, tunnels, and roads. National Road Authorities use Asset Management Systems (AMS) to manage and monitor operational information of assets from European Highways, including access to sensor and inspection data. Interoperability between BIM and AMS systems is vital for a timely and effective decision-making process during the operational phase of these assets. The European project Connected Data for Effective Collaboration (CoDEC) designed a framework to support the connections between AMS and BIM platforms, using linked data principles. The CoDEC Data Dictionary was developed to provide standard data formats for AMS used by European NRA. This paper presents the design and development of an Engineering Structures ontology used to encode the shared conceptualization provided by the CoDEC Data Dictionary. The ontology is evaluated, validated, and demonstrated as a base for data exchange between BIM and AMS.
- Moving from classical towards machine learning stances for bus passengers’ alighting estimation: A comparison of state-of-the-art approaches in the city of LisbonPublication . Cerqueira, Sofia; Arsenio, Elisabete; Barateiro, José; Henriques, RuiPassenger alighting estimation is a critical task in public transport (PT) management, especially for entry-only Automatic Fare Collection (AFC) transport systems where passenger alighting are not recorded. Effective estimation methods are necessary for trip analysis and route planning, offering valuable insights into passengers’ mobility patterns and, subsequently, improving the quality of service. However, the stochastic nature of passenger behaviour challenges the degree of successful alighting estimates. A classic approach to infer the alighting stops of passengers is the use of trip-chaining principles. Since these principles are dispersed across the literature in the field, their comprehensive review is pivotal to establish the best practice for alighting estimation. Still, trip chaining approaches are unable to infer the alighting of non-commuting passengers. This paper addresses these two research gaps by: i) providing a critical overview of the existing principles and methods for alighting estimation; ii) proposing an approach to improve alighting estimation that consistently integrates the most effective state-of-the-art principles on trip-chaining; and iii) further introducing a frequent pattern mining and densitybased clustering solutions to support alighting estimation for non-commuting passengers. Considering the public bus transport in Lisbon city as the guiding case study, the achieved estimation rate by the proposed assembled model is 92%. Moreover, the density-based clustering solution is found to improve the estimation of 11pp against classic trip-chaining principles. Furthermore, the proposed model and acquired results yield actionable value to enhance PT operations and services, ultimately leading to improved bus routing and quality of service.
- A dinuclear oxoperoxomolybdenum(VI) Complex, [Mo2O6(OH)2 (Pyridine Oxide Tetrazolate) 2], displaying the {MoO(O2)(OH)2MoO(O2)}0 core, and its catalytic performance in olefin epoxidationPublication . Nunes, Martinique S.; Neves, Patrícia; Gomes, Ana C.; Mendes, Ricardo F.; Paz, Filipe A. Almeida; D. Lopes, André; Silva, José Paulo da; Pillinger, Martyn; Valente, Anabela A.; Gonçalves, Isabel S.The dinuclear oxoperoxomolybdenum(VI) complex [Mo2O6(OH)2(pto)2] (1), containing a rare example of a hydroxo-bridged {MoO(O2) (μ-OH)2MoO(O2)}0 core, has been synthesized via the reaction of MoO3 with H2O2 and 5-(2-pyridyl-1-oxide)tetrazole (Hpto) and characterized by elemental analysis and ICP-OES, infrared and Raman spectroscopies, single crystal X-ray diffraction, nuclear magnetic resonance, and mass spectrometry. Compound 1 is an effective homogeneous catalyst for olefin epoxidation. The type of oxidant, namely tert-butyl hydroperoxide (TBHP) or H2O2, influences the catalytic performance. For cis-cyclooctene epoxidation, 1/TBHP led to 100% conversion after 4 h at 70 °C, and 1/H2O2 led to 80% conversion after 24 h at 70 °C. Catalyst recycling is feasible using an ionic liquid solvent with high affinity for the catalyst, and product separation via an extraction process. The catalytic potential of 1 was further explored for the chemical valorization of biomass-derived fatty acid methyl esters (FAMEs), namely C18-unsaturated methyl oleate and methyl linoleate derived from vegetable oils. The reaction of FAMEs/TBHP gave mainly epoxidized FAMEs (>97% selectivity at high conversions of 97–100%, at 70 °C). This catalyst is a rare example of a dinuclear organo-oxomolybdenum(VI) compound with the ability to epoxidize FAMEs.
- Coupled phantom cosmological model motivated by the warm inflationary paradigmPublication . Halder, Sudip; Pan, Supriya; Sá, Paulo; Saha, TapanIn this article, we investigate a coupled phantom dark-energy cosmological model in which the coupling term between a phantom scalar field with an exponential potential and a pressureless dark-matter fluid is motivated by the warm inflationary paradigm. Using methods of qualitative analysis of dynamical systems, complemented by numerical solutions of the evolution equations, we study the late-time behavior of our model. We show that contrary to the uncoupled scenario, the coupled phantom model admits accelerated scaling solutions. However, they do not correspond to a final state of the Universe’s evolution and, therefore, cannot be used to solve the cosmological coincidence problem. Furthermore, we show that, for certain coupling parameter values, the total equation-of-state parameter’s asymptotic behavior is significantly changed when compared to the uncoupled scenario, allowing for solutions less phantom even for steeper potentials of the phantom scalar field.
- Strategic analysis in the public sector using semantic web technologiesPublication . Antunes, António Lorvão; Barateiro, José; Cardoso, ElsaThis article addresses the complex challenges that public organizations face in designing, implementing, and evaluating their strategies, where public interest and regulatory compliance often intertwine with strategic objectives. This research investigates the application of ontologies in the field of public sector strategy management to enhance the capacity of organizations to make informed data-driven decisions, efficiently allocate resources, and effectively navigate the intricate landscape of the public sector. The LNEC - National Laboratory for Civil Engineering’s strategy is used as an exploratory case study. Semantic web technologies are used to perform strategy analysis, including validating the strategy formulation and supporting the strategy execution by assessing performance indicators, verifying the design of cause-and-effect relationships between strategic objectives, and monitoring and empirically validating these relationships. The increased interoperability of these technologies enables information sharing across systems and organizations. Following the strategy analysis, recommendations are provided, leading to a more robust and data-driven strategic management approach, enabling accurate, traceable, and continuous monitoring of an organization’s strategy. Theoretical and practical implications are discussed, along with limitations and future work. This research offers a blueprint for public sector organizations seeking to optimize their strategies, foster transparency, and deliver more effective services to the public they serve.
- Euphorbia resinifera: chemical composition and biological properties (short review)Publication . boutoub, Oumaima; Ghadraoui, Lahsen El; Miguel, Maria da GraçaThis review updates the information on the chemical composition of E. resinifera (spurge resin) latex and its biological properties, as well as those from the aerial parts and bee products (honey and propolis), generally without latex. From such review and according to the studies developed so far, it was possible to confirm that the chemical composition of latex and non-latex compounds differs. In the latex, diterpenes, nor sesquiterpenes, triterpenes, and serine proteases (EuRP-61) with 61 kDa predominate despite other minor compounds. The identified protease had anticoagulant, antiplatelet, and peripheral blood cell aggregation inhibitory properties. Phenolics, including flavonoids and tannins, have antioxidant activity and are dominant in the aerial parts of E. resinifera. Phenolic acids and flavonoids, particularly flavanones, flavones, and flavonols and their glycosides, were identified in the spurge resin honey. Generally, honey samples were within the acceptable limit of international standards. Antioxidant activity was reported for this monofloral honey. Antimicrobial activity was also detected in hydroalcoholic extracts of propolis.
- A critical analysis of the marina environmental risk assessment method applied to PortugalPublication . Neves, Maria C.; Cravo, Alexandra; Jacob, José; Correia, CátiaThe MERA (Marina Environmental Risk Assessment) procedure was applied for the first time along the coast of Portugal to classify the risk of 26 marinas on water quality. A risk ranking Atlas was produced to provide managers or decision-makers with spatial information that can help achieve sustainable development goals. The results indicate that the eight marinas in the south coast of the country (Algarve) face the highest risk, primarily due to pressures from navigation activities. However, the ranking generated along the Algarve using indicators of trophic status (TRIX and Eff. Coeff.) based on chemical analysis of in-situ water samples do not align with MERA. The MERA methodology, as it stands, presents significant limitations. Specifically, it does not account for water chemical parameters, sediment contamination, or temporal variability, all of which are crucial for accurate assessments. To enhance the robustness of MERA, this study suggests incorporating additional parameters and metrics that encompass broader environmental indicators.
- ZnO noparticles normalize pancreas function via the GLP-1 and oxidative stress pathways in diabetic ratsPublication . Mirzaei, Fatemeh; Jalili, Cyrus; Khodadadi, Iraj; Hosseini, Nashmin Fayazi; MAJDOUB, Nesrine; Naseri, Nima; Mirzaei, Amir; Abbasi, EbrahimThis experiment was carried out to investigate the effects of ZnO nanoparticles (ZnO NPs) on metabolic parameters, oxidative stress, apoptosis, and pathophysiological alterations of the pancreas in diabetic rats. Nanoparticle was synthesized and its characterizations were determined. We evaluate the toxicity and useful dosage of the ZnO NPs in Wistar male rats. Our experiment showed that 5 mg/kg had a useful effect and was not toxic. Hence, in the next step, the Wistar male rats were randomly divided into 3 groups as follows: (1) control rats (C); (2) diabetic rats (D), (3) diabetic rats received 5 mg/kg NP. After 4 weeks, animals were sacrificed, and blood chemical factors were measured. The oxidative stress, inflammatory, and apoptosis pathways were evaluated. Insulin and glucagon-like peptide-1 (GLP-1) mass was evaluated by immunofluorescence. The morphological changes were evaluated using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, hematoxylin and eosin (H&E), and aldehyde fuchsin. ZnO NP acts as an insulin sensitizer and normalizes blood glucose, GLP-1 levels as well as apoptosis, oxidative stress, and inflammatory pathway gene expression in diabetic rats. ZnO NP also alleviates the pathological alterations in the pancreas. This study showed that a low dose of ZnO NPs protects pancreatic β cells from oxidative stress and apoptosis. Administration of ZnO NP also normalized the pathophysiological alteration of the pancreas, thus normalizing metabolic abnormality.
- Multifaceted impact of exogenous salicylic acid on vicia faba l. under salt stress: plant growth, water status, and photosynthetic performance (OJIP Fluorescence)Publication . ANAYA, FATIMA; Fghire, R.; Wahbi, S.; Carvalho, Inês; Loutfi, K.Purpose This study investigated the effect of salt stress on growth, water status, and photosynthetic activity in faba bean plants and the role of salicylic acid (SA) in mitigating the harmful effects of salt stress. Methods Faba bean plants were subjected to different levels of salt stress (0, 90, 120, and 150 mM NaCl) and salicylic acid (0, 0.5, and 1 mM SA). Salt and SA treatments were applied starting from the seedling stage and continued for two months. Results Results show that salt stress significantly affects the different studied parameters. Salinity strongly decreases the plant weight (fresh and dry) and the plant water status (Leaf Water Potential (LWP), Stomatal conductance (gs), Relative water content (RWC). The analysis of the Photosystem II (PSII) function disruption indicates that salt stress induced an electron transport inhibition at the donor side of the PSII due to the Oxygen-Evolving Complex (OEC) inactivation (positive- K-band) and reduced the PSII unit’s energetic connectivity (positive-L-band). The evaluation of the rate reduction of the end electron acceptor at the Photosystem I (PSI) side revealed that salt stress resulted in gradual decreases in the reduction rates. Nevertheless, the exogenous application of salicylic acid (SA) allowed plants to maintain a high weight/length value with a significant improvement in plant water status. Chlorophyll-a fluorescence analysis shows that SA application improved at the donor side of electron transport (lower intensity of the K and L-band), with a larger pool size under the combination of 0.5 mM SA and high salt stress levels applications. Conclusion These results suggest that the salt stress significantly affects the PSII by the inactivation of the OEC and decreas¬ing the PSII unit’s connectivity. However, SA had a beneficial effect on the PSII and PSI salt stress tolerance in Vicia faba L.
- Testing the diversifying asset hypothesis between clean energy stock indices and oil pricePublication . Dias, Rui; Galvão, Rosa; Cruz, Sandra P.; Irfan, Mohammad; Alexandre, Paulo; Gonçalves, Sidalina; Teixeira, Nuno; Palma, Cristina; Almeida, LilianaIn theory, geopolitical risk and political uncertainty can directly affect energy markets. Fluctuations lead to the cost of clean energy sources as they compete with traditional energy. The purpose of this study is to analyse financial integration and test the diversifying asset hypothesis between clean energy indices, specifically the Clean Energy Fuels (CLNE), Nasdaq Clean Edge Green Energy (CELS), S&P Global Clean Energy (SPGTCLEN), TISDALE Clean Energy (TCEC.CN), Wilderhill (ECO) and West Texas Intermediate (WTI) stock indices, over the period from 1 January 2018 to 23 November 2023. Analysing the results reveals a scenario where most of the clean energy indices show cointegration with each other, indicating long-term relationships that reflect common trends in the clean energy sector. However, the relative independence of the WTI suggests that Oil still acts as an important and potentially diversifying external factor for investors focused on sustainable energy. Structural breaks in 2021 and 2022 in several indices point to significant events that have altered market dynamics, possibly including changes in environmental policies, technological innovations and the impacts of the COVID-19 pandemic. The cointegration evidence and structural breaks provide valuable information for building investment portfolios. Investors can consider the WTI to diversify portfolios dominated by clean energy assets, taking advantage of Oil’s relative independence. On the other hand, the high correlation between clean energy indices suggests that, within this sector, diversification options are more limited, requiring careful analysis of the specific characteristics of each index and the macroeconomic forces affecting them.