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Liposomal co-formulation of Azure A and rose bengal decyl ester as a multi-cellular target approach for photodynamic therapy of colorectal cancer
No full textMultidrug systems offer a promising strategy to improve the efficacy of anticancer treatments, reduce therapeutic doses, and attenuate side effects. In this study, the photosensitizers Azure A (AA) and rose bengal decyl ester (RBDEC) were co-encapsulated in hybrid DPPC/F127 liposomes to target multiple cellular sites. The combined system yielded small unilamellar vesicles (SUVs) with a polydispersity index suitable for biological applications and a zeta potential of +10.57 mV. The encapsulation efficiency of AA and RBDEC is 60.3 and 98.5 %, respectively. In the colorectal adenocarcinoma Caco-2 cells line, photosensitizers showed distinct cellular localization, with RBDEC most targeting the nuclear region and AA the cytoplasm confirmed by confocal microscopy. According to the Chou-Talalay method for drug combinations, the equimolar and lower concentrations (2.5 x 10_6 mol L_ 1 each) exhibited an additive effect, suggesting that even lower concentrations could achieve synergism. The findings indicate that this system exhibits considerable promise, as the combination of drugs facilitates action at multiple sites, thereby increasing the likelihood of cell death. In addition, the system demonstrated greater efficiency at lower concentrations, reducing adverse effects and directing future studies.ACPS acknowledges CAPES (Brazil) for the scholarship (n° 88887.507572/2020–00). LHS thanks CNPq (processes 200176/2024-2 and 303635/2022-3). MIBRS also acknowledges CNPq (process 408561/2023-8). ALT acknowledges UTFPR, CNPq (process 420280/2023–5) and Fundação Araucária (PRD2023361000418, PBA2025201000164) for the financial support. The authors are grateful to the National Institute of Science and Technology in Polysaccharides (INCT Polissacar- ídeos - 406973/2022-9), and Institute for Research and Innovation in Photothermal Imaging (INPIIF - 408454/ 2024-5). We are also grateful to the multiuser laboratory LAMAP/UTFPR, the Foundation for Research and Innovation Support of the State of Santa Catarina (FAPESC), and the Complex of Research Support Centers (Comcap/UEM) for their support
Teaching introductory programming in top universities: a global study of languages, paradigms, assessment, and AI
No full textThis study examines the first two introductory computer science courses (CS1 and CS2) at the world's top universities, focusing on the choice of programming languages and paradigms, assessment types and weights, and policies regarding student use of AI tools. Data were compiled from 150 programming courses across 83 institutions ranked in the Shanghai 2023 Global Ranking of Academic Subjects for Computer Science & Engineering. The analysis reveals that the prevailing languages are Python in CS1 (32.5 %) and Java in CS2 (56.7 %). Typical transitions from CS1 to CS2 involve moving from Python or C to Java. There are some regional preferences: Asian institutions favor lower-level languages like C and C++, whereas European universities explore functional programming languages like Haskell. Regarding programming paradigms, CS1 emphasizes imperative approaches, sometimes introducing object-oriented concepts later in the course, while CS2 consolidates objectoriented programming. However, some CS1 courses adopt a functional paradigm. Course assessments are typically divided into several categories, with a preference for exams and various types of continuous assessments. However, there is also significant use of projects, quizzes, and labs. Examinations usually have the highest weight in the final grade. Course-level policies on students' use of generative AI tools reveal very different approaches, from complete prohibition to active encouragement. These findings offer valuable insights into how leading universities approach programming education in a multidimensional view that includes languages, paradigms, assessments, and AI tools policies.This work was supported by FCT - Fundação para a Ciência e Tecnologia, I.P. by projects: CeDRI, UID/05757/2025 (DOI: 10.54499/UID/05757/2025) and UID/PRR/05757/2025 (DOI: 10.54499/UID/PRR/05757/2025); SusTEC, LA/P/0007/2020 (DOI: 10.54499/LA/ P/0007/2020)
Mechanical Characterization of Eco-Friendly Composites: Green Epoxy Resin Reinforced with Coir Fibers
No full textThe increasing demand for sustainable materials has fostered the development of natural fiber-reinforced composites as eco-friendly alternatives to petroleum-based systems. This work investigates the mechanical performance of GreenPoxy resin reinforced with coir fibers through a comprehensive experimental program. Fiber properties were first characterized by density and tensile tests, while the resin was evaluated under tensile and flexural loading. Composite laminates were then fabricated by hand lay-up using 3% and 6% fiber volume fractions, with both untreated and retted fibers. Mechanical behavior was analyzed using Taguchi design and ANOVA to assess the effects of fiber treatment and content. Untreated fibers displayed slightly higher intrinsic strength, while mercerization enhanced fiber–matrix adhesion, particularly at higher fractions. The composites exhibited promising properties, confirming the potential of coir/GreenPoxy systems for sustainable structural applications.The authors acknowledge the Foundation for Science and Technology (FCT, Portugal) for financial support through national funds FCT/MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/00690/2020) and SusTEC (LA/P/0007/2020)
The relationship between perceived emotional competence and evidence-based nursing: a nationwide non-probabilistic cross-sectional studycclicense-by
No full textEvidence-Based Nursing is imperative for high-quality care, but
its implementation continues to face the know-do gap. While organizational barriers are
often cited, the role of individual competencies, specifically Emotional Competence, in
facilitating adoption remains underexplored on a large scale. This study aimed to analyze
the association between perceived Emotional Competence, Evidence-Based Nursing adoption, and perceived attitudes and barriers in a nationwide sample of nurses registered with
the Portuguese Order of Nurses. Methods: A quantitative, cross-sectional, correlational study was conducted using a non-probabilistic sample of 3014 nurses registered with
the Portuguese Order of Nurses. The Clinical Effectiveness and Evidence-Based Practice
Questionnaire, the Attitudes and Barriers Questionnaire, and the Emotional Competence
Questionnaire were administered. Data were analyzed using bivariate correlations and a
multivariable linear regression model. Results: Nurses reported high levels of perceived
Emotional Competence (M = 204.7; SD = 20.3). In the multivariable regression model, Emotional Competence remained robustly and independently associated with Evidence-Based
Nursing adoption (B = 0.315; p < 0.001), even after adjusting for sociodemographic and
professional covariates. The perception of organizational barriers (e.g., time, incentives) did
not correlate with adoption (rs = 0.011; p = 0.54). Conclusions: Perceived Emotional Competence is a significant and independent correlate of Evidence-Based Nursing adoption.
The results suggest that developing socio-emotional skills, including emotional regulation,
may be a relevant training target to support evidence implementation
Níveis de proficiência digital dos alunos e professores em contexto online: estudo de caso em Moçambique
No full textA pesquisa aborda a crescente digitalização do ensino e a importância das competências digitais tanto para alunos quanto para professores, especialmente no contexto de ensino online em Moçambique. O estudo tem como objetivo investigar os níveis de proficiência digital desses agentes educacionais, analisando os desafios e as oportunidades existentes. Utiliza uma abordagem qualitativa, baseada em um estudo de caso descritivo, com análise documental de políticas educacionais, relatórios internacionais e materiais pedagógicos digitais. Os resultados sugerem políticas públicas voltadas para a inclusão digital, como a expansão da infraestrutura tecnológica, formação contínua de professores e o desenvolvimento de conteúdos digitais contextualizados, essenciais para superar as disparidades educacionais no país. O estudo recomenda ainda um esforço conjunto entre governo, instituições educacionais e organizações internacionais para fortalecer a alfabetização digital e garantir um ensino online mais inclusivo e eficaz
Watercress
No full textWatercress (Nasturtium officinale R. Br.) is a semiaquatic plant of the Brassicaceae family highly appreciated in
the Mediterranean cuisine. It features a sharp, peppery, and slightly tangy taste and is consumed raw in salads
and cooked, especially in soups. Low in fat and sodium, this low-calorie food is rich in vitamin B9 (folates), vitamin
C (ascorbic acid), and vitamin K (phylloquinone). It also contains bioactive compounds such as flavonols,
hydroxycinnamic acids, and glucosinolates (mainly phenethyl isothiocyanate, PEITC). The health-promoting
effects of this cruciferous vegetable have been demonstrated by clinical trials and in vitro and in vivo studies,
which have attributed antioxidant, antiinflammatory, chemopreventive, chemotherapeutic, cardioprotective, and
anticholesterolemic properties to this functional food. Therefore a regular consumption of watercress may help
reach the recommended dietary allowances of certain micronutrients and promote the consumer’s health and
well-being.info:eu-repo/semantics/publishedVersio
Vertical farming: new trends, products, and production approaches
No full textThe text contextualizes increasing urbanization, climate change, and the limitation of natural resources as factors driving the adoption of controlled environment agriculture (CEA) systems. It highlights the potential of vertical farming to optimize the use of water, energy, and space, reduce supply chains and transport-related emissions, and enable greater control over the nutritional quality and safety of food. The editorial also addresses technical, economic, and regulatory challenges, emphasizing the need for technological innovation, integration with public policies, and assessment of economic feasibility. Overall, the work positions vertical farming as a complementary solution to conventional agriculture, playing a relevant role in the transition toward more sustainable urban agri-food systems.The author(s) declared that financial support was received for this work and/or its publication. This work was supported by national funds through FCT/MCTES (PIDDAC): CIMO, UIDB/00690/2025 (doi: 10.54499/UIDB/00690/2025) and UID/PRR/00690/2025 (doi: 10.54499/UID/PRR/00690/2025); and SusTEC, LA/P/0007/2020 (doi: 10.54499/LA/P/0007/2020). Additional support was provided by FCT through the scientific employment stimulus program (contract with M.I.D., CEECINSTLA/00032/2022/CP3032/CT0001), and by the Swedish Research Council for Sustainable Development (FORMAS) through grant number 2021-02447
Population-specific phenotypic plasticity of endangered bivalves in response to extreme events
No full textFreshwater mussels are among the most endangered animal groups, highly sensitive to climate change due to their strict dependence on freshwater habitats. While freshwater mussels are often considered ecologically strict, their distribution across broad environmental gradients raises the possibility of population-specific adaptations mediated by phenotypic plasticity.
This study investigates whether geographically and climatically distinct populations of two freshwater mussel species (Unio pictorum and Unio delphinus) exhibit different transcriptomic responses to prolonged heat stress and whether these responses reveal signs of local adaptation.
We exposed northern and southern populations of both species to gradually increasing temperatures in controlled laboratory conditions, simulating a prolonged thermal extreme event, and RNA-seq was used to quantify differential gene expression.
Results showed strong differences between northern and southern populations of the two species, both in the magnitude and functional composition of transcriptomic responses. Southern populations exhibited intense expression shifts involving classical stress pathways, heat shock proteins, detoxification (cytochrome P450s), apoptosis, and energy metabolism, while northern populations, particularly U. delphinus, showed a markedly subdued response. Notably, U. pictorum's northern population relied heavily on the cytochrome P450 family even at moderate temperatures, while the southern populations of both species activated broader proteostasis and immune responses at higher stress thresholds.
These findings demonstrate clear population-specific phenotypic plasticity, shaped by environmental conditions rather than phylogenetic proximity. They underscore the need for conservation strategies to move beyond species-level management, embracing intraspecific variation as a buffer against climate impacts. As climate change accelerates, safeguarding the evolutionary potential encoded within populations, not just species, is essential to preserving biodiversity resilience.This research was developed under the project EdgeOmics - Freshwater Bivalves at the Edge: Adaptation genomics under climate-change scenarios (PTDC/CTA-AMB/3065/2020) funded by Fundação para a Ciência e a Tecnologia (FCT) through national funds. Fundação para a Ciência e a Tecnologia (FCT) also supported AGS (2023.07625.CEECIND/CP2848/CT0010 and DOI identifier https://doi.org/10.54499/2023.07625.CEECIND/CP2848/CT0010), EF (CEECINST/00027/2021/CP2789/CT0003 and DOI identifier https://doi.org/10.54499/CEECINST/00027/2021/CP2789/CT0003. FCT also provided funds within the scope of the Strategic Funding UIDB/04423/2020 (https://doi.org/10.54499/UIDB/04423/2020), UIDP/04423/2020 (https://doi.org/10.54499/UIDP/04423/2020), and LA/P/0101/2020 (https://doi.org/10.54499/LA/P/0101/2020)
Development of chondroitin sulphate-based scaffolds targeting bone regeneration applications
No full textMestrado de dupla diplomação com a UTFPR - Universidade Tecnológica Federal do ParanáBone tissue is a complex biomaterial composed of proteins and minerals essential for the skeleton's structure and function. However, factors such as ageing, trauma, inflammation, and genetic disorders can compromise bone integrity. While bones possess a natural ability to heal, treating defects remains challenging. Innovative approaches are focusing on substances like chondroitin sulphate (CS), chitosan (CH), and hydroxyapatite (HAp) for their beneficial properties. In this study, HAp/CH scaffolds with different CS concentrations were developed, focusing on bone regeneration. The composition of the scaffolds followed the typical proportion of bone, with 70% HAp as the inorganic component and 30% CH as the organic component. This combination mimics the natural bone matrix and is gradually resorbed by the body, facilitating regeneration. Due to the
addition of acetic acid for CH dissolution, a purification step was carried out using supercritical CO2 (scCO2) to remove it from the final material. Thermogravimetric (TG) analyses showed that scCO2 was effective in removing the acid, with extraction yields ranging from 55% to 100%, depending on the sample, confirming the scaffolds' biological viability. Density and swelling analyses were carried out to characterise the samples. The
values obtained showed a density of approximately 0.05 g/cm³ and swelling capacities ranging from 2.79 to 3.24 g/g, both in line with the data available in the literature. In addition, Fourier transform infrared spectroscopy (FTIR) analysis was used to identify the functional groups and chemical bonds present in the material, providing a clear view of the molecular composition. Cytotoxicity tests showed that the samples were not toxic within 48 hours. Thus, the results indicated that the scaffolds incorporated with CS showed good structural stability and biological behaviour, making them suitable materials for bone regeneration. In addition, the process of obtaining CS is being studied in the project “Obtaining, characterising and evaluating the bioactive potential of chondroitin sulphate from tilapia scales”, to which this thesis contributes.O tecido ósseo é um biomaterial complexo, composto de proteínas e minerais essenciais para a estrutura e a função do esqueleto. No entanto, fatores como envelhecimento, trauma, inflamação e distúrbios genéticos podem comprometer a integridade óssea. Embora os ossos tenham uma capacidade natural de se regenerar, o tratamento de defeitos continua a ser um desafio. As abordagens inovadoras estão se concentrando na utilização de substâncias como o sulfato de condroitina (CS), quitosano (CH) e hidroxiapatite (HAp) dado as suas propriedades benéficas. Neste estudo, foram desenvolvidos scaffolds de
HAp/CH com diferentes concentrações de CS visando aplicações na área da regeneração óssea. A composição dos scaffolds baseou-se na proporção típica do osso que inclui 70% de HAp (componente inorgânico) e 30% de CH (componente orgânico). Esta combinação imita a matriz óssea natural e é gradualmente reabsorvida pelo corpo, facilitando a regeneração. Dada a utilização de ácido acético para solubilizar o CH, a purificação dos materiais foi realizado usando CO2 supercrítico (scCO2). As análises termogravimétricas (TG) mostraram que o scCO2 foi eficaz na remoção do ácido, com rendimentos de
extração variando de 55% a 100%, dependendo da amostra, o que aponta para a viabilidade biológica dos scaffolds. Para caracterizar as amostras, foram realizadas análises de densidade e inchamento. Os valores obtidos indicaram uma densidade de aproximadamente 0,05 g/cm³ e capacidade de inchamento que variou de 2,79 a 3,24 g/g, ambos os parâmetros de acordo com os dados disponíveis na literatura. Adicionalmente,
a análise de espectroscopia de infravermelho por transformada de Fourier (FTIR) foi usada para identificar os grupos funcionais e as ligações químicas presentes no material, fornecendo uma visão clara da composição molecular. Os testes de citotoxicidade mostraram que as amostras não foram tóxicas para um período de 48 horas. Assim, os resultados indicaram que os scaffolds incorporados com CS apresentaram boa estabilidade estrutural e comportamento biológico, tornando-os materiais adequados para uso na regeneração óssea. Adicionalmente, o processo de obtenção de CS está sendo alvo de estudos no projeto “Obtenção, caracterização e avaliação do potencial bioativo do sulfato de condroitina de escamas de tilápia”, para o qual esta tese contribui
Bioactive and chemical characterization of medicinal plants
No full textMestrado de dupla diplomação com a UTFPR, Universidade Tecnológica Federal do ParanáMedicinal plants are used worldwide for the treatment of various diseases, and there is increasing interest in studying their bioactive properties and chemical composition. A deeper understanding of these properties could drive significant advancements in multiple industrial sectors. In this study, we investigated three medicinal plants traditionally used in Brazil and Portugal: Plantago major L., Bidens pilosa L., and Pistacia lentiscus L. The primary objective was to expand scientific knowledge of these species by characterizing their chemical composition and diverse bioactive properties.
The plants were characterized regarding their individual profiles in fatty acids, tocopherols, free sugars, and organic acids through adequate chromatographic methodologies. The hydroethanolic extracts were characterized in terms of phenolic composition and antioxidant and antimicrobial activities. The polyphenolic profile was
analyzed by HPLC-DAD-ESI/MS. The antioxidant activity was assessed through the thiobarbituric acid reactive substances (TBARS) formation inhibition. Finally, the antimicrobial activity was assessed by the microdilution method against bacteria and fungi.
P. major exhibited the highest lipid content (1.7 g/100 g dw), followed by P. lentiscus and B. pilosa (1.2 and 0.6 g/100 g dw, respectively). In all species, palmitic acid (C16:0) was the fatty acid detected in higher relative abundance (between 37.8% and 44.1%). The major tocopherol in P. major and P. lentiscus was alpha-tocopherol (35.5 and 1.7 mg/100 g, respectively), and gamma-tocopherol in B. pilosa (0.09 mg/100 g). B. pilosa contained the highest concentration of free sugars (4.5 g/100 g), followed by P. lentiscus and P. major (3.3 and 0.8 g/100 g, respectively). The most abundant organic acid in B. pilosa and P. lentiscus was quinic acid (0.76 and 0.46 g per 100 g, respectively).
In turn, succinic acid was the most abundant in P. major (1.62 g per 100 g), which was also the plant with higher total organic acids. A wide variety of phenolic compounds was identified in all the studied plants. The major phenolic compounds in P. major, B. pilosa,
and P. lentiscus were verbascoside, quercetin-dimethyl ether rutinoside, and galloylquinic acid, respectively. Regarding antioxidant activity, the hydroethanolic extract of P. lentiscus demonstrated the highest activity, followed by B. pilosa and P. major. For the antibacterial activity, P. major extract exhibited activity against all
bacterial strains tested. P. lentiscus was effective against Salmonella enterica, Yersinia enterocolitica, Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus, while B. pilosa was only effective against Escherichia coli and S. enterica. However, none of the plants showed significant antifungal activity against Aspergillus braziliensis and Aspergillus fumigatus.
In conclusion, the chemical composition, antioxidant, and antimicrobial activities of P. major, B. pilosa, and P. lentiscus were studied, which contributes to the scientific understanding of their potential. The results obtained in this study enable further investigation into their extracts and the validation of their traditional uses.As plantas medicinais são amplamente utilizadas em todo o mundo para o tratamento de diversas doenças. Por isso, há um interesse crescente no estudo propriedades bioativas e composição química dessas plantas, uma vez que este conhecimento pode impulsionar avanços significativos em vários setores industriais.
Neste estudo foram estudadas três plantas medicinais tradicionalmente usadas no Brasil e em Portugal: Plantago major L., Bidens pilosa L. e Pistacia lentiscus L. O objetivo principal foi expandir o conhecimento científico sobre essas espécies, através da
caracterização química e avaliação das propriedades bioativas.
As plantas foram caracterizadas quanto aos perfis individuais de ácidos gordos, tocoferóis, açúcares livres e ácidos orgânicos, através das metodologias cromatográficas adequadas. Por sua vez, os extratos hidroetanólicos foram caracterizados em termos de
composição fenólica e atividades antioxidante e antimicrobiana. A composição fenólica foi analisada por HPLC-DAD-ESI/MS. A atividade antioxidante foi avaliada através do ensaio de inibição da formação de substâncias reativas ao ácido tiobarbitúrico (TBARS).
Por fim, a atividade antimicrobiana foi avaliada pelo método de microdiluições sucessivas em bactérias e fungos.
Quanto ao teor lipídico a P. major apresentou o maior teor (1,7 g/100 g extrato), seguido da P. lentiscus e da B. pilosa (1,2 e 0,6 g/100 g extrato, respectivamente). Em todas as espécies estudadas, o ácido palmítico (C16:0) foi o ácido gordo detetado em maior abundância relativa (entre 37,8% e 44,1%). O alfa-tocoferol foi o tocoferol detetado em maior concentração na P. major e na P. lentiscus (35,5 e 1,7 mg/100 g,
respectivamente), enquanto o gama-tocoferol foi a isoforma que exibiu uma maior concentração na B. pilosa (0,09 mg/100 g). A B. pilosa exibiu ainda a maior concentração de açúcares livres (4,5 g/100 g), seguida da P. lentiscus e da P. major (3,3 e 0,8 g/100 g,
respectivamente). O ácido orgânico mais abundante na B. pilosa e P. lentiscus foi o ácido quínico (0,76 e 0,46 g por 100 g, respectivamente). Por outro lado, o mais abundante em P. major foi o ácido succínico (1,62 g por 100 g).
Uma ampla variedade de compostos fenólicos foi identificada em todas as plantas estudadas. Os compostos fenólicos detetados em maior concentração no extrato hidroetanolico da P. major, B. pilosa e P. lentiscus foram verbascosídeo, quercetina-dimetil éter rutinosídeo e ácido galoilquínico, respectivamente. Em relação à atividade
antioxidante, o extrato hidroetanólico da P. lentiscus demonstrou a maior atividade, seguido da B. pilosa e da P. major. Quanto à atividade antibacteriana, o extrato de P. major exibiu atividade contra todas as cepas bacterianas testadas. A P. lentiscus demonstrou atividade contra a Salmonella enterica, Yersinia enterocolitica, Bacillus
cereus, Listeria monocytogenes e Staphylococcus aureus, enquanto a B. pilosa foi eficaz apenas contra a Escherichia coli e a S. enterica. No entanto, nenhuma das plantas mostrou atividade antifúngica significativa contra a Aspergillus braziliensis e a Aspergillus fumigatus.
Em conclusão, foram estudadas a composição química, as atividades antioxidante e antimicrobiana de P. major, B. pilosa e P. lentiscus, o que contribui para o entendimento científico de seu potencial. Os resultados obtidos neste estudo permitem novas investigações sobre seus extratos e a validação de seus usos tradicionais