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Browsing ISEP – CIETI – Artigos by Field of Science and Technology (FOS) "Engenharia e Tecnologia"
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- Alleviation of Fe-induced chlorosis of soybean plants grown in calcareous soil by a freeze-dried iron fertilizer containing siderophores produced by Rhizobium radiobacterPublication . Arcas, Alejandra; Sadeghi, S. Maryam; Lucena, Juan J.; Vindeirinho, João M.; Soares, Eduardo V.; Soares, Helena M. V. M.; López-Rayo, SandraThe concerns about the unsustainability of traditional synthetic Fe chelates lead to the search for new environmentally friendly alternatives, such as siderophores-based fertilizers. In this work, the focus was on the evaluation of a bio-based Fe-chelate fertilizer obtained from the culture of the siderophore-producer bacterium Rhizobium radiobacter. The suitability of a freeze-dried fertilizer formulated from a R. radiobacter culture labeled with 57Fe to alleviate Fe chlorosis in soybean plants cultivated in calcareous soil was analyzed and the new potential Fe fertilizer was evaluated in comparison to the traditional synthetic chelate o,oEDDHA/57Fe3+. This natural chelate was able to maintain chlorophyll content stable during all the pot trials and presented greater Fe concentration in the remaining soil fractions serving as an Fe pool for a long time whereas o,oEDDHA/57Fe3+ could supply Fe quickly. The new bio-based Fe siderophore fertilizer, derived from R. radiobacter culture, could be a green substitute to conventional synthetic chelates to address Fe chlorosis in calcareous soil conditions.
- Alzheimer's diagnosis beyond cerebrospinal fluid: Probe-Free Detection of Tau Proteins using MXene based redox systems and molecularly imprinted polymersPublication . Arjum, Ajith Mohan; Deshpande, Sudhaunsh; Dunlop, Tom; Norman, Beth; Oliviera, Daniela; Vulpe, Georgeta; Moreira, Felismina; Sharma, SanjivPhosphorylated Tau proteins are promising biomarkers for the diagnosis and prognosis of Alzheimer's disease. This study presents a novel voltametric sensor using a vanadium MXene polydopamine (VxPDA) redox active composite and a Tau-441-specific polyaniline molecularly imprinted polymer (PANI MIP) for the sensitive detection of Tau-441 in interstitial fluid (ISF) and plasma. The VxPDA/PANI MIP sensor demonstrates a broad detection range of 5 fg/mL to 5 ng/mL (122 aM/L to 122 pM/L) in ISF without the use of redox mediators, with a lower limit of detection (LOD) of 2.3 fg/mL (60 aM/L). Furthermore, a handheld device utilizing this technology successfully detects Tau-441 in artificial serum with high sensitivity (5 fg/mL to 150 fg/mL (122 aM/L to 366 aM/L)) and specificity within a clinically relevant range. The rapid detection time (∼32 min) and low cost (∼£20/device) of this sensor highlight its potential for minimally invasive, early AD diagnosis in clinical settings. This advancement aims to facilitate a transition away from invasive cerebrospinal fluid (CSF)-based diagnostic techniques for AD.
- Amplified Sensitivity in SERS Detection of L1CAM With Silver Plasmonic Mesoporous Silica Capsules on an Imprinted FilmsPublication . Castaño-Guerrero, Yuselis; Arjones-Fernández, Belén; Moreira, Felismina T. C.; Alvarez-Puebla, Ramon A.; Correa-Duarte, Miguel A.; Águas, H.; Sales, M. Goreti F.This study presents a novel approach for dual detection, leveraging a combination of a Raman reporter-bearing nanomaterial and molecular imprinting polymers (MIP). A core-shell Au-Ag nanoparticles (Au-Ag NPs) encapsulated in mesoporous silica nanocapsules (Au-Ag NCs) and a new MIP-based material targeting L1CAM are used. The MIP prepared via surface imprinting on a carbon screen-printed electrode (C-SPE) used thionine (TH) as a monomer. The plasmonic Au-AgNCs are further functionalized with the Raman reporter 4-mercaptobenzoic acid (MBA) and anti-L1CAM for selective detection by surface-enhanced Raman scattering (SERS) spectroscopy. The biosensor's analytical performance is evaluated using both SERS and electrochemical impedance spectroscopy (EIS). EIS analysis reveals a linear response within the concentration range of 0.1 to 100 ng mL−1 in buffer and serum samples. SERS demonstrates a sensitivity ten times higher than EIS. Selectivity study demonstrates the biosensor's excellent specificity toward L1CAM, with minimal interference from other compounds such as creatinine, glucose, and carbohydrate antigen 19-9 (CA 19-9). The Raman signal from the reporter molecule correlates with increasing L1CAM concentrations, reinforcing the analytical findings obtained through electrochemical analysis. Thus, the combination of dual detection and recognition capabilities presents promising potential for detecting diverse biomarkers, especially in critical scenarios where reducing false-positive or false-negative errors is crucial.
- Bioinspired host-tailored polymers based on molecular imprinting for cytokine assessmentPublication . Ferreira, Bianca; Correa-Duarte, Miguel; Marques, Arcelina; Moreira, Felismina; Martins, GabrielaMolecular imprinting undergone a substantial boost driven by the awareness of molecularly imprinted polymers (MIPs)-ligand recognition skills. In particular, the introduction of natural-based compounds like cyclodextrins into the structural scaffold of synthetic recognition elements attracted great importance as a novel route to design more friendly-environments for protein binding, while promoting higher selectivity features. Herein, carbon electrodes doped with platinum nanoparticles supported on multiwalled carbon nanotubes and functionalized with polyallylamine (MWCNTs-PAH/Pt) were electrochemically modified with an imprinted sensing layer of poly(β-cyclodextrin-pyrrole) (poly(β-CD-Py)) towards interleukin 6 (IL-6) monitoring. The analytical performance of the biosensor was evaluated by using Cyclic Voltammetry and Electrochemical Impedance Spectroscopy techniques. Along the assembly, experimental parameters like nanomaterial deposition, monomer-protein concentrations and template removal solutions were carefully optimized and discussed. Furthermore, the electrodeposited film was characterized in terms of composition, morphology and structure using scanning electron microscopy (SEM) and Raman spectroscopy. Under optimal conditions, the developed sensor was able to rebind IL-6 over a wide linear range [1 pg/mL – 100 ng/mL], displaying high sensitivity, quick electrochemical response, and specific binding of the target molecule. Overall, this work reported the relevance of using hostguest complexes directly embedded in polymeric chains to generate newly controlled electrochemical sensors holding great potential for protein biosensing.
- Biological and Medicinal Properties of Natural Chromones and ChromanonesPublication . Gaspar, Alexandra; Garrido, E. Manuela P. J.; Borges, Fernanda; Garrido, Jorge M. P. J.Emerging threats to human health require a concerted effort to search for new treatment therapies. One of the biggest challenges is finding medicines with few or no side effects. Natural products have historically contributed to major advances in the field of pharmacotherapy, as they offer special characteristics compared to conventional synthetic molecules. Interest in natural products is being revitalized, in a continuous search for lead structures that can be used as models for the development of new medicines by the pharmaceutical industry. Chromone and chromanones are recognized as privileged structures and useful templates for the design of diversified therapeutic molecules with potential pharmacological interest. Chromones and chromanones are widely distributed in plants and fungi, and significant biological activities, namely antioxidant, anti-inflammatory, antimicrobial, antiviral, etc., have been reported for these compounds, suggesting their potential as lead drug candidates. This review aims to update the literature published over the last 6 years (2018–2023) regarding the natural occurrence and biological activity of chromones and chromanones, highlighting the recent findings and the perspectives that they hold for future research and applications namely in health, cosmetic, and food industries.
- Bonding to Psychedelics: Synthesis of Molecularly Imprinted Polymers Targeting 4-Bromo-2,5-dimethoxyphenethylamine (2C-B)Publication . Martins, Daniel; Fernandes, Carlos; Mendes, Ricardo F.; Cagide, Fernando; Silva, António Fernando; Borges, Fernanda; Garrido, Jorge; Garrido, JorgeThe increasing interest in utilizing psychedelics for therapeutic purposes demands the development of tools capable of efficiently monitoring and accurately identifying these substances, thereby supporting medical interventions. 4-Bromo-2,5-dimethoxyphenethylamine (2C-B) has gained significant popularity as one of the most widely used psychedelic compounds in non-medical settings. In this study, we aimed to create a material with selective recognition of 2C-B by synthesizing a series of molecularly imprinted polymers (MIP) using 2C-B as the template and varying ratios of methacrylic acid (MAA) as the functional monomer (1:2, 1:3, and 1:4). Both thermal and microwave-assisted polymerization processes were employed. The molar ratio between the template molecule (2C-B) and functional monomer (MAA) was 1:4, utilizing a microwave-assisted polymerization process. Isotherm studies revealed a Langmuir’s maximum absorption capacity (Bmax) value of 115.6 μmol·mg−1 and Kd values of 26.7 μM for this material. An imprint factor of 4.2 was determined for this material, against the corresponding non-imprinted polymer. The good selectivity against 14 other new psychoactive substances highlighted the material’s potential for applications requiring selective recognition. These findings can contribute to the development of tailored materials for the detection and analysis of 2C-B, supporting advancements in non-medical use monitoring and potential therapeutic models involving psychedelics.
- Comparative Studies on the Photoreactivity, Efficacy, and Safety of Depigmenting AgentsPublication . Mota, Sandra; Rosa, Gonçalo P.; Barreto, Maria Carmo; Garrido, Jorge; Sousa, Emília; Cruz, Maria T.; Almeida, Isabel F.; Quintas, Clara; Garrido, Jorge; Mordon, SergeDepigmenting products are increasingly used to counteract skin hyperpigmentation and related psychosocial issues. This study aimed to compare different depigmenting agents—4-butylresorcinol; bakuchiol; tranexamic acid; ascorbyl glucoside; α-arbutin; and ascorbic acid—for photoreactivity; tyrosinase inhibition; and safety. Photoreactivity was assessed using the Reactive Oxygen Species assay. In vitro tyrosinase inhibition was compared, and cell viability was assessed in B-16V melanocytes to evaluate safety. Results showed 4-butylresorcinol, ascorbyl glucoside, and α-arbutin are non-photoreactive, while for ascorbic acid and bakuchiol it was not possible to reach conclusive results due to the lack of specificity of the ROS assay. 4-Butylresorcinol, acting as a competitive inhibitor, displayed potent tyrosinase inhibition, followed by ascorbic acid and bakuchiol. Both 4-butylresorcinol and bakuchiol reduced cell viability in a concentration-dependent manner. The insights obtained in this work support the development of depigmenting products by providing useful scientific guidance on the photostability, tyrosinase inhibitory efficacy, and skin safety of depigmenting agents.
- Consideration of Sustainability in Projects: A Cross-Sectional Quantitative AnalysisPublication . Magano, José; Silvius, Gilbert; Nogueira, Teresa; Hamed, Farzad; Nogueira, Teresa; Carmenado, IgnacioThe consideration of sustainability in projects is one of the most critical global trends in project management today, as projects are instrumental in the sustainable development of organisations and society. In the growing literature on this topic, most studies take a qualitative approach, often based on single case studies, and quantitative studies are underrepresented. To address these limitations, this study aims to examine the extent to which different aspects and perspectives of sustainability are integrated into projects by reporting a quantitative analysis of the consideration of sustainability in 134 projects. The analysis used the Sustainable Project Management Maturity Model SPM3 to analyse the level at which sustainability was considered in the projects. The results show that, on average, sustainability is considered at a reactive level, with the desired levels of consideration on average one level higher (proactive). When considering the different triple bottom line perspectives, the economic perspective scores highest, followed by the social and environmental perspectives. The study also shows that building-related projects score higher on sustainability considerations than other project types, as do larger projects. Limitations of the study include its European focus, the relatively small sample size, and the fact that the data was collected in different locations over a four-year period, which raises the possibility of subjective differences in the evaluation of individual projects. Nevertheless, the study can be seen as a ‘wake-up call’ for project practitioners, who need to be more proactive in this regard if projects are to be the route to sustainability.
- Critical minds: enhancing education with ChatGPTPublication . Costa, Alexandra R.; Lima, Natércia; Viegas, Clara; Caldeira, Amélia; Costa, Alexandra; Lima, Natércia; Viegas, Clara; Caldeira, AméliaThe use of AI tools, particularly ChatGPT, has been widespread in recent years. Its application in education has been criticized by some and supported by others. In this article we present the case of a work carried out as part of a course unit in a computer science degree program in which the use of ChatGPT was not only encouraged but required. Students were asked to use this tool ethically and critically, comparing the results with bibliographical references. A questionnaire addressing students’ perceptions about the work and ChatGPT usage was performed after delivering the task. Results showed that students were motivated to carry out the work and understood that its widespread use requires critical thinking and compliance with ethical principles. The teacher acknowledge that some students developed these competences while performing this task and were able to deliver a quality, well supported essay. The development of this competences was also identified by some students.
- Editorial: Bio-based solutions for sustainable development of agriculture, volume IIPublication . Soares, Eduardo V.; Petropoulos, Spyridon A.; Soares, Helena M. V. M.; Vasconcelos, Marta[editorial excerpt] The modern cropping industry has to address food security challenges related to the increasing world population, the pressure of climate change on crop production, and the adverse effects of anthropogenic activities on agro-ecosystems (Boix-Fayos and de Vente, 2023; Grigorieva et al., 2023). Therefore, various strategies have been suggested (e.g. Green Deal, Soil Deal, Farm to Fork, and European Biodiversity) focusing on a gradual and mild transition toward sustainable cropping systems and agronomic solutions. Biostimulants and bio-based solutions in general have been considered viable solutions to be integrated into the current agronomic schemes to overcome the challenges that the cropping sector is facing or is expected to face in the near future.
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