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- Driving tourism development: multicriteria decision-making in Rio de Janeiro’s tourism sectorPublication . Ferreira, Fernanda A.; Coutinho, José Augusto da Fonseca Pinto; Gomes, Carlos Francisco Simões; Santos, Marcos dosAs operations stabilized after the onset of the Covid-19 pandemic, many economic sectors have gradually resumed activities, with some nearing pre-pandemic levels. Tourism is no exception, as it continues to be used as a source of resource acquisition and socioeconomic development. The purpose of this study is to promote the development of the tourism sector in the municipality of Rio de Janeiro by applying the Analytic Hierarchy Process (AHP) and AHP-Gaussian (AHP-G) multicriteria analysis methods to support potential public and/or private investments in tourism. The findings of this study will help a travel agency make a strategic decision about where to open a new branch, taking into account the sector’s potential in Rio de Janeiro. The study found that São Conrado and Ipanema are ideal neighbourhoods for establishing a new travel agency branch. Furthermore, the methodology used in this study can be used as a guideline for other organizations in the field looking to undertake similar evaluations, providing a structured approach to decision-making and investment evaluation.
- Sequential move model for quantity and quality competition in the restaurant industryPublication . Ferreira, Flávio; Koerich, GuilhermeThis paper examines a competition in both quality and quantity between two asymmetric restaurants. The model that we consider is a Stackelberg duopoly on quantities (sequential decision-making), after a simultaneous choice of quality. Our findings indicate that the restaurant with the best reputation provides a greater variety of higher-quality food compared to its competitor. We also examine how variations in restaurants’ reputations impact market equilibrium outcomes. We demonstrate that an increase in the reputation gap between restaurants boosts the profits of both estab lishments, enhances consumer surplus, and improves social welfare. Additionally, in comparison to the scenario under the Cournot model (simultaneous decision making), small restaurant’s profits are lower under Stackelberg model, while the opposite holds for the large restaurant’s profits and for social welfare.
- Gold Single Atom Doped Defective Nanoporous Copper Octahedrons for Electrocatalytic Reduction of Carbon Dioxide to EthylenePublication . Zhao, Yang; Wang, Yanan; Yu, Zhipeng; Song, Chao; Wang, Jingwei; Huang, Haoliang; Meng, Lijian; Liu, Miao; Liu, LifengElectrocatalytic CO2 reduction into high-value multicarbon products offers a sustainable approach to closing the anthropogenic carbon cycle and contributing to carbon neutrality, particularly when renewable electricity is used to power the reaction. However, the lack of efficient and durable electrocatalysts with high selectivity for multicarbons severely hinders the practical application of this promising technology. Herein, a nanoporous defective Au1Cu single-atom alloy (DeAu1Cu SAA) catalyst is developed through facile low-temperature thermal reduction in hydrogen and a subsequent dealloying process, which shows high selectivity toward ethylene (C2H4), with a Faradaic efficiency of 52% at the current density of 252 mA cm−2 under a potential of −1.1 V versus reversible hydrogen electrode (RHE). In situ spectroscopy measurements and density functional theory (DFT) calculations reveal that the high C2H4 product selectivity results from the synergistic effect between Au single atoms and defective Cu sites on the surface of catalysts, where Au single atoms promote *CO generation and Cu defects stabilize the key intermediate *OCCO, which altogether enhances C−C coupling kinetics. This work provides important insights into the catalyst design for electrochemical CO2 reduction to multicarbon products.
- Ir Nanoparticles Synergistically Regulated by B, N Co-Doping in Carbon for pH-Universal Bifunctional Electrocatalysts towards Energy-Efficient Hydrogen ProductionPublication . Huang, Hongli; Meng, Lijian; li, Haibo; Li, Rui; Zeng, Suyuan; Yao, Qingxia; Chen, Hongyan; Qu, Kong-GangThe ultralow-potential hydrazine oxidation reaction (HzOR) can be integrated with hydrogen evolution reaction (HER) to construct the overall hydrazine splitting (OHzS) system, thus realizing energy-saving hydrogen production. Meanwhile, the real electrocatalytic processes normally involve the constantly changed pH and also need to operate under different pH conditions. Therefore, designing advanced pH-universal electrocatalysts with high compatibility for HER and HzOR is of greatly practical significance. Herein, ultrafine Ir nanoparticles embedding in B, N-codoped carbon (Ir/BNC) were facilely synthesized with one Ir-based complex and boric acid by simple mixing and pyrolysis. To reach the current density of 10 mA cm−2, the bifunctional Ir/BNC merely demands the low potentials of −4.8/-6.3/-38.5 mV for HER, 7.5/157.8/330.1 mV for HzOR, and 19/236/358 mV for OHzS in the alkaline, neutral and acidic electrolytes, respectively, all greatly outperforming commercial Pt/C and displaying the huge energy-saving advantage for pH-universal hydrogen generation over the conventional water splitting. Underlyingly, the codoping of abundant B and N heteroatoms with different electronic modulation effects can play synergistical roles to Ir active sites, endowing with the pH-universal multifunctionality as well as the boosted intrinsic unit activity. Additionally, the large surface area, rich pores and highly graphitized carbon also collectively ensure the remarkable apparent performance for bifunctional HER and HzOR. This work supplies a promising strategy for exploiting pH-universal HER and HzOR bifunctional electrocatalysts, greatly potential to the practical energy-efficient hydrogen generation.
- Optical immunosensor panel using quantum dot-antibody conjugates for highly sensitive detection of carbohydrate antigen 19–9 (CA19-9)Publication . Oliveira, Daniela; Oliveira, Pedro; Xu, Ana; Rodrigues, Eduarda; Guerreiro, Susana G.; Castro, Rafael C.; Ribeiro, David S. M.; Santos, João L. M.; Piloto, Ana Margarida L.This study introduces a fluorescent immunosensor colour panel with antibody-conjugated quantum dots for detecting CA19-9 in human serum. The immunosensors presented decreasing fluorescence with increasing CA19-9 concentrations, with a linear detection range from 0.01 to 501.87 U mL−1 and detection limits of 1.66 × 10⁻⁴, 2.71 × 10⁻⁴, and 5.45 × 10⁻⁴ U mL−1 for the green-, orange-, and red-emitting conjugates in human serum. These limits are well below the 37 U mL−1 cutoff for early pancreatic cancer risk. The immunosensor panel is simple, sensitive, and specific, offering a visual colour readout for rapid CA19-9 detection, making it ideal for point-of-care applications. The results highlight the potential of the developed conjugates as a sensitive fluorescence colour panel for detecting CA19-9 across a wide range in human serum, both below and above the pancreatic cancer cutoff. With just 200 μL of sample and a single pre-filtration step, the assay delivers results in under 15 min, offering a cost-effective and efficient platform for point-of-care use.
- Engineering a Sustainable Future with EPS@ISEPPublication . Malheiro, Benedita; Guedes, Pedro; Leal Filho, Walter; Gasparetto Rebelatto, Bianca; Annelin, Alice; Boström, Gert-OlofThe challenge of engineering education is to transform engineering students into agents of innovation and well-being. In addition to solid scientific and technical knowledge, critical thinking, problem-solving and interpersonal competencies, it implies the ability to design and implement solutions supported by ethical and sustainability principles. With this goal in mind, the European Project Semester (EPS) provides a student-centred project-based learning framework. It is offered by a group of European higher education institutions, including the Instituto Superior de Engenharia do Porto (ISEP), the engineering school of the Polytechnic of Porto. Students work in teams of four to six, from different fields of study and nationalities, to design solutions to problems that affect individuals, society or the planet, taking into account the state of the art, the market and the ethical and sustainability implications of their decisions. These solutions are then implemented in a proof-of-concept prototype. Most of the projects address problems in education, the environment, food production and smart cities and have a strong educational, ethical and sustainability drive, encouraging students to develop sustainability competencies. This work analyses team papers of illustrative EPS@ISEP projects searching for evidences of the development of sustainability competencies. The proposed method maps keywords related to the sixteen United Nations Sustainable Development Goals to the contents of team papers by applying natural language processing and reusing the list of SDG keywords proposed by Auckland University. The results confirm EPS@ISEP fosters sustainability competencies in engineering undergraduates.
- Publicações BIM: IV pós-graduação em Coordenação BIMPublication . Martins, Adriana; Monteiro, Ana; Carvalho, André; Melo, Bruna Beppler; Siqueira, Carolina Gavron; Teixeira, Diogo; Gomes, Edson; Nunes, Fábio; Barbosa, Hélder; Assunção, Luiza; Castro, Madalena; Mota, Nuno; Vieira, Rui; Cabral, Sara; Marques, Sara; Ribeiro, Diogo; Vaz, Jorge Vieira; Pinto-Faria, José; Santos, Ricardo; Gavina, Rui(Excerto Prefácio)Os trabalhos aqui compilados têm origem nos relatórios apresentados pelos autores — enquanto estudantes— na unidade curricular de Projeto Integrador, da quarta edição do Curso de Pós-Graduação “Coordenação BIM” (Building Information Modelling) promovido pelo ISEP (Instituto Superior de Engenharia do Porto), pela ESAP (Escola Superior Artística do Porto) e pela BIM Academy de Barcelona, em 2023. Na sua génese, os relatórios foram o resultado de trabalhos de grupos, com a dotação temporal de cinco semanas, apresentados e defendidos publicamente, sobre temas relevantes escolhidos pelos próprios estudantes, no âmbito da Coordenação de Processos BIM. A escolha livre dos temas, nesta última unidade curricular do curso, mostra-se muito diversificada, desde a aplicação sobre um case-study, e de um modo mais ou menos sincrético, das aprendizagens adquiridas nas anteriores unidades curriculares, até à exploração de temas muito concretos com origem nos interesses específicos dos estudantes, sejam eles de âmbito profissional, académico ou pessoal. A organização deste livro reflete a organização sucessiva dos temas, tendo em conta a sua temática restrita, partindo dos elementos básicos de modelação, passando pela organização dos processos de coordenação e a sua aplicação em contextos específicos, como a eficiência energética ou a reabilitação do edificado, assim:
- Microwave-assisted synthesis of hierarchical BiOBr/BiOF Z-scheme heterojunction for activating peroxymonosulfate toward photodegradation of the recalcitrant levofloxacinPublication . Guohua Dong; Dongzhe Zhang; Xinjia Zhang; Zhuangfang Zhang; Dong-feng Chai; Lijian Meng; Jinlong Li; Ming Zhao; Wenzhi ZhangHerein, a novel Z-scheme BiOBr/BiOF heterojunction was synthesized via one-step microwave-assisted hydrothermal method, which was integrated with peroxymonosulfate (PMS) to design a sulfate radical (•SO4−) based advanced oxidation processes (AOPs) system through PMS activation (BiOBr/BiOF-PMS) toward Levofloxacin (LFX) photodegradation. In order to achieving an optimal degradation efficiency, the formed BiOBr/BiOF-PMS was systematically investigated and the operational parameters for LFX photodegradation were thoroughly optimized. Thereby, the optimal BiOBr/BiOF exhibits a higher photodegradation efficiency of 89.8 % toward LFX via PMS activation compared to others including PMS alone, BiOBr, BiOF and BiOBr/BiOF with varied ratios. Furthermore, the BiOBr/BiOF has superior stability for multiple cycles and universal applicability for degrading various contaminants. This can mainly be attributed that the formed heterojunction between BiOBr and BiOF and the enhanced concentration of oxygen vacancies (OVs) of BiOBr/BiOF heterojunction, which can synchronously promote the separation and transmission of the photogenerated charges (e−/h+) and thereby lead to more reactive oxygen species (ROS). As well, the expanded optical responsiveness and increased specific surface area of BiOBr/BiOF are also mainly responsible for the improved photodegradation capability. Free radical capture experiments and ESR technique verify that the •O2− is the primary ROS and •SO4− and •OH play subordinative role. The photodegradation pathways of LFX were unraveled based on the identified intermediates with a liquid-chromatography-mass (LC-MS) technique. Consequently, this study offers a novel route by developing Bi-based heterojunction photocatalyst to activate PMS for refractory antibiotic photodegradation.
- Covalent organic framework assisted low-content ultrafine ru on porous N-doped carbon for efficient hydrogen evolution reactionPublication . Kong-Gang Qu; Zhi-Fei Chen; Li-Hui Wang; Hai-Bo Li; Su-Yuan Zeng; Rui Li; Li-Jian Meng; Hong-Yan Chen; Qing-Xia Yao(Excerpt) Pt-based materials are the benchmarked catalysts in the cathodic hydrogen evolution reaction (HER) of water splitting; the prohibitive cost and scarcity of Pt immensely impede the commercialization of hydrogen energy. Ru has aroused significant concern because of its Pt-like activity and much lower price. However, it’s still a top priority to minimize the Ru loading and pursue the most superior cost performance. Herein, N-rich covalent organic framework (COF) was employed to assist the preparation of ultrafine Ru, including nanoclusters and single atoms loaded onto porous N-doped carbon by a simple impregnation-pyrolysis process with a low Ru content of 6.60 wt%, exhibiting superior HER activity with mass activity of 21.86 and 11.52 A mg-1 Ru (@100 mV) in alkaline and acidic conditions, separately 14.7 and 2.12 times higher than that of commercial Pt/C.
- Translation and validation of the Portuguese version of the internet severity and activities addiction questionnaire (ISAAQ-10) towards the identification of problematic social media use: A population studyPublication . Dores, Artemisa R.; Antunes, Cátia; Geraldo, Andreia; Carvalho, Irene P.; Marques, António; Pereira, Ilídio; Chamberlain, Samuel R.; Lochner, Christine; Ioannidis, Konstantinos; Dores, Artemisa; Geraldo, Andreia; Pereira da Silva Marques, António JoséProblematic usage of the internet (PUI) refers to a pattern of internet use that results in negative consequences in an individual’s life. It encompasses a broad spectrum of activities, which require assessment in terms of both severity and diversity, for a comprehensive understanding. This study aimed to translate the Internet Severity and Activities Questionnaire (ISAAQ-10) into Portuguese, to analyze its psychometric properties and to explore the validity of the ISAAQ-10 social networking use activity score towards identifying problematic social media use. A snowball sampling method was used, with participants completing an online survey comprising sociodemographic questions and the Portuguese versions of the ISAAQ-10, Internet Addiction Test-10 (IAT-10), Internet Gaming Disorder Scale–Short-Form (IGDS9-SF), and Bergen Social Media Addiction Scale (BSMAS). The psychometric analysis included internal reliability testing using Cronbach’s alphas and test-retest reliability, a confirmatory factor analysis (CFA), and convergent validity testing between the ISAAQ-10 and IAT-10. The concurrent validity of the ISAAQ-10 was also examined. A total of 590 young adults (85.1 % female), aged between 18 and 35 years, participated in this study. The ISAAQ-10 presented good internal consistency ( α =0.93), with a test-retest correlation of r = 0.865; 95 % CI: 0.669–0.939. and a unidimensional structure that explained 48.3 % of the total variance. The convergent validity of the ISAAQ-10’s total score was established through a high Pearson’s correlation (r = 0.574; p ≤ .001) with the IAT-10’s total score. Pearson’s correlations between the ISAAQ-10 gaming activity score and the IGDS9-SF (r = 0.873; p < .001), and between the ISAAQ-10 social networking use activity score and the BSMAS (r = 0.670; p < .001), respectively, supported the instrument’s concurrent validity. This work provides support for the Portuguese translation of the ISAAQ-10, which can be employed to identify the severity of problematic usage of the internet in a population sample. It also provides the first validation of the ISAAQ-10 social networking use activity score, which can be employed to identify problematic social media use within a predominately female university student sample. This study further establishes the ISAAQ-10 as a valid and reliable tool for population studies and, specifically, for the identification of problematic social media use.