Publications Repository of the Polytechnic Institute of Bragança
Not a member yet
30168 research outputs found
Sort by
Seasonal and daily patterns in the flight activity of Trioza erytreae (Del Guercio), vector of huanglongbing (HLB)
No full textThe psyllid Trioza erytreae (del Guercio, 1918) (Hemiptera: Triozidae) is one of the vectors of Candidatus liberibacter spp., the causal agent of the huanglongbing (HLB) the main citrus disease worldwide. In this study, we investigated for the first time how the flight behavior of T. erytreae is influenced by factors such as sex or daily and seasonal pattern fluctuations by using a flight mill device under controlled laboratory conditions. RESULTS: Our results showed that T. erytreae can fly an average distance of 16.20 m at a mean speed of 6 m per minute, but a few individuals were able to fly much longer, reaching a maximum distance of 395 m. Females displayed a higher flight capacity than males. Moreover, we found that T. erytreae is not confined to diurnal flight alone, as the psyllids demonstrated the ability to fly during the night, emphasizing the need for comprehensive vector control strategies that account for nocturnal activity. CONCLUSION: Understanding the flight behavior of vector insects is essential for devising effective control measures aimed at mitigating the spread of vector-borne diseases. Further research in this area will contribute to a more nuanced understanding of vector movement and the development of more precise control measures.The authors are grateful to the European Union grant, programme H2020 entitled: PRE-HLB: Preventing HLB epidemics for ensuring citrus survival in Europe. H2020-SFS-2018-2 Topic SFS-05-2018-2019-2020-new and emerging risks to plant health (Project no. 817526) as well as to the Foundation for Science and Technology (FCT, Portugal) for financial support by national funds FCT/MCTES to CIMO (UIDB/00690/2020 e UIDP/00690/2020)
Ante-projeto de instalações térmicas de uma fábrica de farinha de bolota
Get PDFO objetivo do projeto foi desenvolver um sistema térmico para a desidratação de bolotas, utilizando uma produção de 1 ton/h durante 40 horas semanais, com base na bolota da azinheira (Quercus rotundifolia). A análise das infraestruturas locais e das necessidades complementares foi realizada após uma visita à fábrica, identificando-se alguns constrangimentos, como a limitação do espaço para instalação de coletores solares térmicos e problemas no processo de separação da casca e do núcleo da bolota. O processo de desidratação visa obter o núcleo da bolota desidratado para a produção de farinha, sendo necessário um controle rigoroso da humidade. Foram analisadas três tecnologias para fornecer o calor necessário, além de combinações para determinar o custo total do calor necessário ao processo de desidratação (LCOH). O relatório também apresenta soluções energéticas e construtivas para melhorar o desempenho e reduzir os custos da fábrica.info:eu-repo/semantics/publishedVersio
Development of LAMP Primers for the Detection of Pyrethroid Resistance Mutations in Varroa destructor
Get PDFVarroa destructor is one of the main threats to Apis mellifera L., directly affecting colony health and contributing to their global decline. Control of this mite is traditionally achieved using acaricides, with pyrethroids such as tau-fuvalinate and fumethrin being the most used, acting on voltage-gated sodium channels (VGSC). However, the intensive use of these compounds by beekeepers has led to the emergence of resistance, associated with mutations at residues 918 and 925 of the VGSC gene [1]. Traditional methods for detecting these mutations, such as PCR, TaqMan and RT-PCR, are effective but require expensive laboratory equipment. In this context, Loop-mediated Isothermal Amplification (LAMP) is a promising alternative, offering rapid and cost-effective detection without the need for thermal cycling [2]. LAMP is based on the use of a set of four to six primers, including two inner primers (FIP and BIP), two outer primers (F3 and B3), and optionally two loop primers (LoopF and LoopB), which are introduced to accelerate the amplification reaction [3]. This study aimed to develop specific LAMP primers, using the NEB LAMP software, for the detection of the main mutations associated with Varroa destructor resistance to pyrethroids in Portugal. The predictive efficiency, specificity, and thermodynamic properties of the designed primers were assessed using BLAST, eLAMP, and OligoAnalyzer tools, considering qPCR parameters. This work successfully identified specific primer sets, including loop primers, for the detection of the mutation at position 925, which may be used in future experimental validations for rapid diagnostic applications
Navigating tomorrow’s wallet: unveiling the distinctive financial journeys across generations
No full textThis study examines the distinctive consumer journeys of Generations X, Y, and Z in financial services, specifically the process of opening a bank account. We employed a qualitative approach and conducted six online focus groups with bank account holders. The findings weave a compelling narrative: Generation X, cautious in their digital approach; Generation Y, seamlessly navigating both digital and non-digital realms; and Generation Z, boldly embracing the entirety of their financial journey through digital channels. Breaking new ground, this research pioneers a fresh perspective by delving into the consumer journey within financial services from the customer’s lens, offering a nuanced understanding of the evolving consumer journey in the financial sector. Beyond the academic realm, our findings hold tangible implications for industry practitioners seeking to adapt to different generations’ diverse preferences and behaviors in their financial interactions
Collaborative work between Polytechnic higher education students: manufacturing processes, safety and sustainability
No full textThe link with the real working environment, combined with the sharing of knowledge and collaboration between students from different courses, was the basis of a teaching experience involving students from the Mechanical Technology I course unit of the Mechanical Engineering degree course and the Safety and Environment course unit of the Higher Professional Technical Course in Sustainable Technologies in Mechanics and Vehicles, at a Polytechnic Higher Education Institution in the north of Portugal. The final objective was to carry out collaborative work on metalworking processes, the safety at work related to these processes, and waste management
Synthesis of carbon nanotubes from polyolefin waste: mass balance and gas phase composition
No full textThe valorization of plastic solid waste (PSW) through thermochemical routes has emerged as a sustainable strategy to address the growing accumulation of these materials. Among the most attractive products, carbon nanotubes (CNTs) stand out due to their high added-value and potential applications in catalysis, sensors, and environmental remediation. CNT synthesis from plastics typically involves thermal decomposition of the polymer into a carbon-rich gas fraction, followed by its deposition on metallic nanoparticles to form CNTs. Optimizing this process requires a detailed understanding of both the mass balance and gas composition. In this work, CNTs were synthesized by chemical vapor deposition (CVD) from low-density polyethylene (LDPE), high-density polyethylene (HDPE), and polypropylene (PP) using a nickel–iron (NiFe) catalyst (synthesis details presented elsewhere [1]). The experiments were performed in a one-chamber reactor, with 1 g of plastic loaded in the upper zone (400–450 °C) and 0.2 g of NiFe in the lower zone (850 °C). The system was heated for 1 h and then held for 0.5 h under a N2 flow (50 cm3 min-1). Generated gases were analyzed in situ by gas chromatography with flame ionization detection (GC-FID). After reaction, solid and liquid fractions were collected and weighed. Characterization of similar CNTs can be consulted in previous publications [1-3]. The results are summarized in Fig. 1. As shown in Fig. 1a, the solid fraction yields were similar for all polymers (35–38%), while HDPE produced a higher liquid fraction than LDPE and PP. The gas fraction dominated in all cases, suggesting catalyst deactivation or an inadequate catalyst-to-plastic ratio. Three major gases were detected (Fig. 1b): methane >> propylene > ethylene. LDPE and PP showed comparable gas distributions, whereas HDPE generated markedly less methane and propylene, consistent with the mass balance trends.This work was financially supported by national funds through FCT/MCTES (PIDDAC): CeDRI (DOI:10.54499/UIDB/05757/2020 and DOI: 10.54499/UIDB/05757/2020); CIMO (DOI: 10.54499/UIDB/00690/2020 and DOI: 10.54499/UIDP/00690/2020); SusTEC (DOI: 10.54499/LA/P/0007/2020); and by project “Estudo técnicoeconómico para a valorização de resíduos de embalagens plásticas na produção de nanotubos de carbono” financed by Sociedade Ponto Verde. F. F. Roman and A. S. Silva acknowledge FCT for the research grants SFRH/BD/143224/2019 and SFRH/BD/151346/2021, respectively
Automated construction and semantic interoperability for digital twins: integrating heterogeneous data with large language models
No full textDigital twins are increasingly used, as they allow the creation of detailed virtual representations of physical products and systems. They face, however, significant challenges such as heterogeneous data integration and high costs. This article presents an innovative methodology that uses Large Language Models to unify information and automate the generation of Digital Twin models. The proposal comprises several modules, covering the stages of data collection, semantic processing, modular construction and validation of the Digital Twin. In this way, the proposed model guarantees interoperability, efficiency and scalability for various domains.The study was developed under the project A-MoVeR – “Mobilizing Agenda for the Development of Products & Systems towards an Intelligent and Green Mobility”, operation n.º 02/C05-i01.01/2022.PC646908627-00000069, approved under the terms of the call n.º 02/C05-i01/2022 – Mobilizing Agendas for Business Innovation, financed by European funds provided to Portugal by the Recovery and Resilience Plan (RRP), in the scope of the European Recovery and Resilience Facility (RRF), framed in the Next Generation UE, for the period from 2021 -2026
From Human to Posthuman: The Strategic Role of Virtual Influencers in Contemporary Marketing
No full textThis chapter explores the growing phenomenon of Virtual Influencers (VIs) in digital advertising and their transformative impact on brand communication. As artificial intelligence and computer-generated imagery enable the creation of lifelike digital personas, VIs offer marketers a new set of tools to engage consumers across global markets. The chapter examines the theoretical foundations of parasocial interaction and source credibility to understand how audiences respond to these non-human figures
A Alma de um Território: A Marca Territorial Chaves como Expressão de Identidade Coletiva
No full textEste artigo de opinião analisa a nova marca territorial do Município de Chaves sob a lente do marketing territorial e das teorias contemporâneas de branding. Argumenta-se que uma marca territorial eficaz deve transcender a dimensão visual, constituindo-se como um sistema identitário profundamente enraizado na história, na cultura e nas aspirações da comunidade. O caso de Chaves destaca-se pela articulação exemplar entre herança patrimonial e visão estratégica, posicionando a marca como um vetor de diferenciação simbólica e de geração de valor económico, cultural e turístico sustentado. A autenticidade da proposta, aliada à sua capacidade de gerar envolvimento emocional e sentido de pertença, constitui o núcleo da sua força diferenciadora e da sua sustentabilidade a longo prazo
Barreiras na adesão à higiene das mãos
No full textA higiene das mãos é uma medida essencial na prevenção de infeções associadas aos cuidados de saúde (IACS), mas a sua prática continua aquém do recomendado. Este estudo teve como objetivo identificar as principais barreiras à adesão à higiene das mãos entre profissionais de saúde do interior Norte de Portugal. A investigação seguiu uma metodologia quantitativa, descritiva, correlacional e transversal, com uma amostra de 65 profissionais, maioritariamente enfermeiros. Os dados foram recolhidos através de um questionário, constituído por questões de caraterização e a escala BAHM (Barreiras à Adesão à Higiene das Mãos), validada para a população portuguesa. O estudo respeitou os princípios éticos e obteve parecer favorável da comissão de ética do IPB. Os resultados mostram que as principais barreiras não estão ligadas à falta de formação, mas sim a fatores organizacionais. Destacam-se a ausência de incentivos para quem cumpre e de sanções para quem não cumpre, a má localização dos pontos de higienização, a escassez de materiais e a sobrecarga de trabalho. Estes fatores refletem falhas na cultura institucional e nas condições de trabalho, dificultando a aplicação prática da higiene das mãos, mesmo quando os profissionais reconhecem a sua importância. A formação e o treino não foram percepcionados como barreiras significativas, sugere que os profissionais possuem os conhecimentos necessários, mas enfrentam obstáculos que dificultam a sua aplicação. Sem diferenças significativas em função da idade ou do sexo, mas os enfermeiros demonstraram maior percepção de barreiras, especialmente nas dimensões de avaliação, feedback e clima organizacional, possivelmente devido à sua maior proximidade às exigências do cuidado direto. Conclui-se que a melhoria da adesão à higiene das mãos exige uma abordagem institucional forte, com liderança ativa, reforço das condições estruturais e uma cultura centrada na segurança do doente