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  1. 1

    Child Engagement in Inclusive Preschools: Contributions of Classroom Quality and Activity Setting

    Publicação
    por Coelho, Vera
    Outros Autores: Cadima, Joana; Pinto, Ana Isabel
    Preschool process quality and activity setting are considered important aspects influencing child engagement. As such, it is important to understand how educational settings can promote engagement, particularly for children with disabilities and/or at risk. This observational study describes process quality and activity setting in inclusive preschools, analyzing its predictive role for child engagement. Participants were 184 children attending 39 preschools. Three groups of children, nested within classrooms, were considered: with disabilities (n = 45), at risk (n = 59), typically developing (n = 80). Child Observation in Preschool assessed engagement and activity setting; Classroom Assessment Scoring System assessed quality of teacher–child interactions. Research Findings: Results from multilevel regressions show that classroom emotional support and organization and more time in free play were positively predicting child engagement, whereas more time in whole group was a negative predictor of engagement. Besides these main effects, an interaction effect between child developmental functioning and activity settings was found. For at-risk children, more time in whole-group activities had greater negative effects on child engagement. For children with disabilities, more time in free-play had greater positive effects on child engagement. Practice or Policy: Results contribute to inform teachers regarding the importance of individualizing interactions and planning activity settings to promote engagement and participation in inclusive preschools.
    2019 artigo Portugal acesso aberto
  2. 2

    Vine-Canes as a Source of Value-Added Compounds for Cosmetic Formulations

    Publicação
    por Moreira, Manuela M.
    Outros Autores: Rodrigues, Francisca; Dorosh, Olena; Pinto, Diana; Costa, Paulo C.; Švarc-Gajić, Jaroslava et al.
    The majority of works about vine-canes are focused on the evaluation of their chemical composition and antioxidant potential. To the best of our knowledge, the possible applications of produced extracts in cosmetic formulations have never been explored. The aim of the present study was to evaluate the antioxidant properties of vine-canes subcritical water extracts for use as active ingredients in the cosmetic industry. For that, the phenolic content and antioxidant activity of six vine-cane varieties, namely Alvarinho and Loureiro from the Minho region and Touriga Nacional and Tinta Roriz (TR) from both the Douro and Dão regions, were evaluated through spectrophotometric and chromatographic methods. All extracts presented similar antioxidant activity and the highest phenolic content was reported for TR variety from the Douro region (33.7 ± 1.9 mg GAE/g dw). The capacity of vine-cane extracts to capture reactive oxygen species superoxide (O2∙−) was also studied, with the highest IC50 value being obtained for Loureiro variety (56.68 ± 2.60 µg/mL). Furthermore, no adverse effects on HaCaT and HFF-1 dermal cell lines in concentrations below 100 and 1000 μg/mL, respectively, were determined. Finally, Loureiro vine-cane extract was incorporated into a topical formulation, and physical and microbiological properties were within expected values, demonstrating that vine-canes extracts can be successfully incorporated in cosmetic products.
    2020 artigo Portugal acesso aberto
  3. 3

    Formulation, Characterization, and Cytotoxicity Evaluation of Lactoferrin Functionalized Lipid Nanoparticles for Riluzole Delivery to the Brain

    Publicação
    por Teixeira, Maria Inês
    Outros Autores: Lopes, Carla Martins; Gonçalves, Hugo; Catita, José; Silva, Ana Margarida; Rodrigues, Francisca et al.
    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with a very poor prognosis. Its treatment is hindered by a lack of new therapeutic alternatives and the existence of the blood–brain barrier (BBB), which restricts the access of drugs commonly used in ALS, such as riluzole, to the brain. To overcome these limitations and increase brain targeting, riluzole-loaded nanostructured lipid carriers (NLC) were prepared and functionalized with lactoferrin (Lf), facilitating transport across the BBB by interacting with Lf receptors expressed in the brain endothelium. NLC were characterized with respect to their physicochemical properties (size, zeta potential, polydispersity index) as well as their stability, encapsulation efficiency, morphology, in vitro release profile, and biocompatibility. Moreover, crystallinity and melting behavior were assessed by DSC and PXRD. Nanoparticles exhibited initial mean diameters between 180 and 220 nm and a polydispersity index below 0.3, indicating a narrow size distribution. NLC remained stable over at least 3 months. Riluzole encapsulation efficiency was very high, around 94–98%. FTIR and protein quantification studies confirmed the conjugation of Lf on the surface of the nanocarriers, with TEM images showing that the functionalized NLC presented a smooth surface and uniform spherical shape. An MTT assay revealed that the nanocarriers developed in this study did not cause a substantial reduction in the viability of NSC-34 and hCMEC/D3 cells at a riluzole concentration up to 10 μM, being therefore biocompatible. The results suggest that Lf-functionalized NLC are a suitable and promising delivery system to target riluzole to the brain
    2022 artigo Portugal acesso aberto
  4. 4

    Salicornia ramosissima: A New Green Cosmetic Ingredient with Promising Skin Effects

    Publicação
    por Correia, Ana
    Outros Autores: Silva, Ana Margarida; Moreira, Manuela M.; Salazar, Miguel; Švarc-Gajić, Jaroslava; Brezo-Borjan, Tanja et al.
    This study aims to validate a new cosmetic ingredient from Salicornia ramosissima S J. Woods through in vitro and ex vivo assays. The halophyte extracts were obtained by subcritical water extraction (SWE) at different temperatures (110, 120, 140, 160 and 180 °C). The antioxidant/radical scavenging activities and the phenolic profile were screened for all extracts. The optimal extract was assessed in keratinocytes and fibroblasts, while permeation assays were performed in Franz cells. The inhibitory activity of hyaluronidase and elastase was also evaluated. The sample extracted at 180 °C presented the highest phenolic content (1739.28 mg/100 g of dry weight (dw)). Despite not being efficient in the sequestration of ABTS•+, this extract scavenged the DPPH• (IC50 = 824.57 µg/mL). The scavenging capacity of superoxide (O2•−) and hypochlorous acid (HOCl) was also considerable (respectively, IC50 = 158.87 µg/mL and IC50 = 5.80 µg/mL). The cell viability assays confirmed the absence of negative effects on keratinocytes, while the fibroblasts’ viability slightly decreased. The ex vivo permeation of rutin, quercetin and syringic acid after 24 h was, respectively, 11, 20 and 11%. Additionally, the extract showed a good elastase and hyaluronidase inhibitory activity. The results obtained support the S. ramosissima bioactivity as a cosmetic ingredient.
    2022 artigo Portugal acesso aberto
  5. 5

    Evaluation of the Biological Potential of Himanthalia elongata (L.) S.F.Gray and Eisenia bicyclis (Kjellman) Setchell Subcritical Water Extracts

    Publicação
    por Gomes, Inês
    Outros Autores: Rodrigues, Helena; Rodrigues, Carla; Oliveira, Marta Marques; Paíga, Paula; Paiva, Alexandre et al.
    Neuroprotection is a need that remains unmet in treating chronic neurodegenerative disorders, despite decades of extensive research. To find new neuroprotective compounds, extracts of Himanthalia elongata (L.) S.F.Gray and of Eisenia bicyclis (Kjellman) Setchell were obtained through subcritical water extraction applying a four-step temperature gradient. The fractions obtained were screened against brain enzymes involved in neurodegenerative etiology, namely in Alzheimer’s and Parkinson’s diseases, and against reactive oxygen and nitrogen species, all contributing factors to the progression of neurodegeneration. Results showed no significant enzyme inhibition but strong radical scavenging activities, particularly in the fourth fraction, extracted at the highest temperature (250 °C), highlighting their ability to retard oxidative and nitrosative stresses. At higher temperatures, fractions were composed of phenolic compounds and Maillard reaction products, a combination that contributed to their antioxidant activity and, consequently, their neuroprotective properties. All fractions were evaluated for the presence of iodine, 14 organochlorine and 7 organophosphorus pesticides, and pharmaceuticals used in Alzheimer’s and Parkinson’s diseases (14), psychiatric drugs (8), and metabolites (8). The fractions studied did not present any of the screened contaminants, and only fraction 1 of E. bicyclis should be used with caution due to iodine content.
    2022 artigo Portugal acesso aberto
  6. 6

    Study of the Potential Accumulation of the Pesticide Alpha-Endosulfan by Microplastics in Water Systems

    Publicação
    por Martinho, Sílvia D.
    Outros Autores: Fernandes, Virgínia Cruz; Figueiredo, Sónia; Delerue-Matos, Cristina
    Microplastics (MP) are spread into all ecosystems and represent a threat to the equilibrium of the environment and human health, not only due to their intrinsic characteristics but also to their action as effective carriers of contaminants, such as pesticides, pharmaceuticals, polychlorinated biphenyls and polycyclic aromatic hydrocarbons. The pesticide α-endosulfan is persistent and spread in the environment. The MP are another possible way of dissemination to be considered in the fate of this pesticide. The adsorption dynamics of α-endosulfan by six different MP (low-density polyethylene—LDPE, polyethylene-co-vinyl acetate, unplasticized polyvinyl chloride, polyamide 6, polystyrene granule, polypropylene granule) with different sizes/shapes and chemical compositions were evaluated. The most critical situation was identified for the system LDPE (particle size < 300 μm). Equilibrium studies (48 h equilibrium time) were performed for distilled, tap and filtered river water. Based on the Langmuir model parameters, the highest maximum adsorption capacity was obtained for distilled water, followed by filtered river and tap waters (i.e., 366 ± 39, 247 ± 38, 157 ± 22 μg/g). The obtained results demonstrate the important role that microplastics may have in the fate and transport of pesticides and their potentially harmful effect on the environment, which requires further investigation
    2022 artigo Portugal acesso aberto
  7. 7

    Schedulability analysis for CAN bus messages of periodically-varying size

    Publicação
    por Hussain, Ishfaq
    Outros Autores: Souto, Pedro; Bletsas, Konstantinos; Awan, Muhammad Ali; Tovar, Eduardo
    Conventional CAN bus schedulability analysis assumes that all messages with a given identifier have the same worst-case length. In this paper we extend that analysis to a more general model in which messages with a given identifier may have different lengths, that vary according to a known periodic pattern.That is, for some positive integer S, we assume that the length of message instances n and n + S with the same id is the same. By leveraging such patterns, where present, our new analysis allows for a more efficient use of CAN bus bandwidth than the application of conventional analysis, which can be pessimistic. This may be interesting when a given node sends the values of multiple signals with different periods. In such a scenario, the conventional CAN schedulability analysis would require either the use of different ids for different signals (assuming there are enough of them), which leads to a higher bandwidth overhead because of the reduplication of message headers, or using only one id, but pessimistically always assuming the maximum possible length of the message, for safety reasons.
    2022 artigo Portugal acesso restrito
  8. 8

    The carboxylic acid transporters Jen1 and Jen2 affect the architecture and fluconazole susceptibility of Candida albicans biofilm in the presence of lactate

    Publicação
    por Alves, Rosana
    Outros Autores: Mota, Sandra; Silva, Sónia; F. Rodrigues, Célia; P. Brown, Alistair J.; Henriques, Mariana et al.
    Candida albicans has the ability to adapt to different host niches, often glucose-limited but rich in alternative carbon sources. In these glucose-poor microenvironments, this pathogen expresses JEN1 and JEN2 genes, encoding carboxylate transporters, which are important in the early stages of infection. This work investigated how host microenvironments, in particular acidic containing lactic acid, affect C. albicans biofilm formation and antifungal drug resistance. Multiple components of the extracellular matrix were also analysed, including their impact on antifungal drug resistance, and the involvement of both Jen1 and Jen2 in this process. The results show that growth on lactate affects biofilm formation, morphology and susceptibility to fluconazole and that both Jen1 and Jen2 might play a role in these processes. These results support the view that the adaptation of Candida cells to the carbon source present in the host niches affects their pathogenicity.
    2017 artigo Portugal acesso aberto
  9. 9

    Improved Bus Contention Analysis for 3-Phase Tasks

    Publicação
    por Arora, Jatin
    Outros Autores: Rashid, Syed Aftab; Nelissen, Geoffrey; Maia, Cláudio; Tovar, Eduardo
    The 3-phase task execution model has shown to be a good candidate to tackle the memory bus contention problem. It divides the execution of tasks into computation and memory phases that enable a fine-grained memory bus contention analysis. However, existing works that focus on the bus contention analysis for 3-phase tasks, neglect the fact that memory bus contention strongly relates to the number of bus/memory requests generated by tasks, which, in turn, depends on the content of the cache memories during the execution of those tasks. These existing works assume that the worst-case number of bus/memory requests will be generated during all the memory phases of all tasks, irrespective of the already existing content in the cache memory. This overestimates the memory bus contention of tasks, leading to pessimistic worst-case response time (WCRT) bounds. This work proposes a holistic approach towards bus contention analysis for 3-phase tasks by (1) deriving an upper bound on the actual cache misses of tasks that lead to bus/memory requests; (2) improving State-of-the-Art (SoA) bus contention analysis of two bus arbitration schemes that dominate all existing works on the bus contention analysis for 3-phase tasks; and (3) performing an extensive experimental evaluation under different settings to compare the proposed analysis against the SoA. Results show that incorporating a tighter bound on the number of cache misses of tasks into the bus contention analysis can lead to a significant improvement in task set schedulability.
    2023 artigo Portugal acesso aberto
  10. 10

    Appraisal of a new potential antioxidants-rich nutraceutical ingredient from chestnut shells through in-vivo assays – A targeted metabolomic approach in phenolic compounds

    Publicação
    por Pinto, Diana
    Outros Autores: Almeida, Andreia; López-Yerena, Anallely; Pinto, Soraia; Sarmento, Bruno; Lamuela-Raventós, Rosa et al.
    Chestnut (Castanea sativa) shells (CSS) are a source of bioactive compounds with well demonstrated in-vitro antioxidant properties. Nevertheless, no in-vivo studies have already evaluated this effect. This study evaluated the effects of the oral daily administration of an eco-friendly CSS extract (50 and 100 mg/kg per body weight (b. w.)) to rats regarding in-vivo antioxidant activity, glucose and lipids levels, and metabolomic profiling of poly- phenols by LC-ESI-LTQ-Orbitrap-MS. The results demonstrated the in-vivo antioxidant properties in the animals liver, kidney and blood serum, as well as protective effects against hemolysis and rising of blood glucose and lipids levels. New insights on metabolomic profiling of polyphenols proved their absorption and further biotransformation by phase I (hydrogenation and hydroxylation) and II reactions (glucuronidation, methylation and sulfation). This is the first study that attempted to validate a novel nutraceutical ingredient extracted from CSS by in-vivo assays, corroborating the outcomes screened by in-vitro assays
    2023 artigo Portugal acesso aberto