Browsing by Author "Fernandes, Catarina"
Now showing 1 - 10 of 13
Results Per Page
Sort Options
- Aprender com os conhecimentos e as experiências das criançasPublication . Coelho, Adriana; Paretskaya, Anna; Tavares, Andreia; Monho, Andreia; Lucas, Cássia; Fernandes, Catarina; Palma, Inês; Gomes, Mafalda; Arvela, Margarida; Pereira, Margarida; Neves, Mariana; Rosário, Marta; Brito, Nadine; Rocha, Rute; Costa, Sara; Pereira, Vera; Gil, Francisco Baptista; Rocha, Rute; Fernandes, CatarinaCerta vez, perguntei a uma criança: "Qual é a forma da Terra?" Ela respondeu: "Na sala de aula, por causa da professora, digo que a Terra é redonda. Mas quando vou de viagem, o carro nunca faz uma curva para cima e para baixo!" Este aparente paradoxo foi o ponto de partida para a elaboração deste livro, intitulado «Aprender com os conhecimentos e as experiências das crianças». A resposta espontânea da criança revela uma realidade com a qual nos deparamos frequentemente: a convivência simultânea de duas conceções distintas no pensamento infantil — uma de natureza escolarizada e outra de base experiencial. A conceção escolarizada surge do que é ensinado formalmente na escola — o conhecimento “correto” do ponto de vista científico-escolar. Já a conceção experiencial está enraizada nas observações e vivências do quotidiano. Assim, uma criança pode afirmar, em contexto escolar, que a Terra é redonda, mas, fora desse ambiente, perceber o mundo como plano, com base na experiência concreta de se deslocar de carro, sem "curvas para cima ou para baixo". Esse tipo de raciocínio evidencia a importância de reconhecer, escutar e compreender o conhecimento que as crianças já possuem, antes mesmo da intervenção educativa. Como futuras professoras e educadoras, defendemos que é essencial antecipar essas ideias prévias e orientar as crianças no processo de (re)construção do conhecimento, de forma significativa e integrada com as suas experiências diárias
- Behavioral inhibition in childhood: European Portuguese adaptation of an observational measure (Lab-TAB)Publication . Faisca, Luis; Ferreira, Laura Inês; Fernandes, Catarina; Gagne, Jeffrey R.; Martins, Ana T.The assessment of behaviorally inhibited children is typically based on parent or teacher reports, but this approach has received criticisms, mainly for being prone to bias. Several researchers proposed the additional use of observational methods because they provide a direct and more objective description of the child's functioning in different contexts. The lack of a laboratory assessment of temperament for Portuguese children justifies the adaptation of some episodes of the Laboratory Temperament Assessment Battery (Lab-TAB) as an observational measure for behavioral inhibition. Method: In our study, we included 124 children aged between 3 and 9 years and their parents. The evaluation of child behavioral inhibition was made by parent report (Behavioral Inhibition Questionnaire) and through Lab-TAB episodes. Parental variables with potential influence on parents’ reports were also collected using the Social Interaction and Performance Anxiety and Avoidance Scale (SIPAAS) and the Parental Overprotection Measure (POM). Results and Discussion: The psychometric analyses provided evidence that Lab-TAB is a reliable instrument and can be incorporated in a multi-method approach to assess behavioral inhibition in studies involving Portuguese-speaking children. Moderate convergence between observational and parent report measures of behavioral inhibition was obtained. Mothers’ characteristics, as well as child age, seem to significantly affect differences between measures, being potential sources of bias in the assessment of child temperament.
- Eco-friendly methods for extraction and modification of cellulose: an overviewPublication . Magalhães, Solange; Fernandes, Catarina; Pedrosa, Jorge F. S.; Alves, Luís; Medronho, Bruno; Ferreira, Paulo J. T.; Rasteiro, Maria da GraçaCellulose is the most abundant renewable polymer on Earth and can be obtained from several different sources, such as trees, grass, or biomass residues. However, one of the issues is that not all the fractionation processes are eco-friendly and are essentially based on cooking the lignocellulose feedstock in a harsh chemical mixture, such as NaOH + Na2S, and water, to break loose fibers. In the last few years, new sustainable fractionation processes have been developed that enable the obtaining of cellulose fibers in a more eco-friendly way. As a raw material, cellulose’s use is widely known and established in many areas. Additionally, its products/derivatives are recognized to have a far better environmental impact than fossil-based materials. Examples are textiles and packaging, where forest-based fibers may contribute to renewable and biodegradable substitutes for common synthetic materials and plastics. In this review, some of the main structural characteristics and properties of cellulose, recent green extraction methods/strategies, chemical modification, and applications of cellulose derivatives are discussed.
- Ectopic expression of CITED2 prior to reprogramming, promotes and homogenises the conversion of somatic cells into induced pluripotent stem cellsPublication . Charneca, João; Matias, Ana Catarina; Escapa, Ana Luisa; Fernandes, Catarina; Alves, Andre; Santos, João; Nascimento, Rita; Bragança, JoséCited2 plays crucial roles in mouse embryonic stem cells self-renewal, the initiation of the somatic reprogramming process into induced pluripotent stem cells (iPSC) and the suppression of cell senescence. Here, we investigated the potential of CITED2 expression in combination with the Oct4, Sox2, Klf4 and c-Myc factors for reprogramming of primary mouse embryonic fibroblasts (MEF) at passage 2 and 4. The ectopic CITED2 expression in primary MEF prior to the onset of the reprogramming process, generated iPSC with less variability in the expression of endogenous pluripotency-related genes. In contrast, part of the MEF reprogrammed without ectopic expression of CITED2 at passage 4 originated partially reprogrammed iPSC or pre-iPSC. However, the overexpression of CITED2 in the pre-iPSC was insufficient to complete the reprogramming process into iPSC. These results indicated that ectopic CITED2 expression at the onset of the reprogramming process in combination with the reprogramming factors promotes a complete and homogeneous conversion of somatic cells into iPSC.
- Enhancing cellulose and lignin fractionation from acacia wood: optimized parameters using a deep eutectic solvent system and solvent recoveryPublication . Magalhães, Solange; Aliaño González, María José; Rodrigues, Mariana; Fernandes, Catarina; Mendes, Cátia V. T.; Carvalho, Maria Graça V. S.; Alves, Luís; Medronho, Bruno; Rasteiro, Maria da GraçaCellulose and lignin, sourced from biomass, hold potential for innovative bioprocesses and biomaterials. However, traditional fractionation and purification methods often rely on harmful chemicals and high temperatures, making these processes both hazardous and costly. This study introduces a sustainable approach for fractionating acacia wood, focusing on both cellulose and lignin extraction using a deep eutectic solvent (DES) composed of choline chloride (ChCl) and levulinic acid (LA). A design of experiment was employed for the optimization of the most relevant fractionation parameters: time and temperature. In the case of the lignin, both parameters were found to be significant variables in the fractionation process (p-values of 0.0128 and 0.0319 for time and temperature, respectively), with a positive influence. Likewise, in the cellulose case, time and temperature also demonstrated a positive effect, with p-values of 0.0103 and 0.028, respectively. An optimization study was finally conducted to determine the maximum fractionation yield of lignin and cellulose. The optimized conditions were found to be 15% (w/v) of the wood sample in 1:3 ChCl:LA under a treatment temperature of 160 degrees C for 8 h. The developed method was validated through repeatability and intermediate precision studies, which yielded a coefficient of variation lower than 5%. The recovery and reuse of DES were successfully evaluated, revealing remarkable fractionation yields even after five cycles. This work demonstrates the feasibility of selectively extracting lignin and cellulose from woody biomass using a sustainable solvent, thus paving the way for valorization of invasive species biomass.
- Lignin extraction from acacia wood: crafting deep eutectic solvents with a systematic D-optimal mixture-process experimental designPublication . Fernandes, Catarina; Aliaño González, María José; Gomes, Leandro Cid; Bernin, Diana; Gaspar, Rita; Fardim, Pedro; Reis, Marco S.; Alves, Luís; Medronho, Bruno; Rasteiro, Maria Graça; Varela, CarlaLignin is a complex biopolymer whose efficient extraction from biomass is crucial for various applications. Deep eutectic solvents (DES), particularly natural-origin DES (NADES), have emerged as promising systems for lignin fractionation and separation from other biomass components. While ternary DES offer enhanced fractionation performance, the role of each component in these mixtures remains unclear. In this study, the effects of adding tartaric acid (Tart) or citric acid (Cit) to a common binary DES mixture composed of lactic acid (Lact) and choline chloride (ChCl) were investigated for lignin extraction from acacia wood. Ternary Cit-based DES showed superior performance compared to Tart-based DES. Using a combined mixture-process D-Optimal experimental design, the Lact:Cit:ChCl DES composition and extraction temperature were optimized targeting maximum lignin yield and purity. The optimal conditions (i.e., Lact:Cit:ChCl, 0.6:0.3:0.1 molar ratio, 140 degrees C) resulted in a lignin extraction yield of 99.63 +/- 1.24 % and a lignin purity of 91.45 +/- 1.03 %. Furthermore, this DES exhibited feasible recyclability and reusability without sacrificing efficiency.
- Lignin extraction from waste pine sawdust using a biomass derived binary solvent systemPublication . Magalhães, Solange; Filipe, Alexandra; Melro, Elodie; Fernandes, Catarina; Vitorino, Carla; Alves, Luís; Romano, Anabela; Rasteiro, Maria G.; Medronho, Bruno; MDPILignocellulosic biomass fractionation is typically performed using methods that are somehow harsh to the environment, such as in the case of kraft pulping. In recent years, the development of new sustainable and environmentally friendly alternatives has grown significantly. Among the developed systems, bio-based solvents emerge as promising alternatives for biomass processing. Therefore, in the present work, the bio-based and renewable chemicals, levulinic acid (LA) and formic acid (FA), were combined to fractionate lignocellulosic waste (i.e., maritime pine sawdust) and isolate lignin. Different parameters, such as LA:FA ratio, temperature, and extraction time, were optimized to boost the yield and purity of extracted lignin. The LA:FA ratio was found to be crucial regarding the superior lignin extraction from the waste biomass. Moreover, the increase in temperature and extraction time enhances the amount of extracted residue but compromises the lignin purity and reduces its molecular weight. The electron microscopy images revealed that biomass samples suffer significant structural and morphological changes, which further suggests the suitability of the newly developed bio-fractionation process. The same was concluded by the FTIR analysis, in which no remaining lignin was detected in the cellulose-rich fraction. Overall, the novel combination of bio-sourced FA and LA has shown to be a very promising system for lignin extraction with high purity from biomass waste, thus contributing to extend the opportunities of lignin manipulation and valorization into novel added-value biomaterials.
- Mirrored-self misidentification in a patient with probable Alzheimer dementiaPublication . Fernandes, Catarina; Taveira, Isabel; Nzwalo, HipólitoA 77-year-old-man who was a retired primary school teacher with probable Alzheimer dementia diagnosed after 2 years of progres sive short-term memory loss and predominant hippocampal atro phy onmagnetic resonance scan of the brain was brought to the out patient neurology clinic by his wife because of persistent ab normal behavior. The caretaker reported that he was frequently puzzled and astonished by his own mirror image. His medical his tory was remarkable for controlled hypertension and type 2 diabe tes. He did not have any personal or family history of psychiatric dis ease. There were no recent changes with the patient’s regular medications (rivastigmine, 9.5 mg daily transdermally; enalapril; and metformin). His wife described him as being a very quiet and relaxed person until the start of restrictions imposed by the COVID-19 pandemic, when he started with complaints of seeing a strangeman whenever he saw his face reflection in the mirror.
- New deep eutectic solvent assisted extraction of highly pure lignin from maritime pine sawdust (Pinus pinaster Ait.)Publication . Fernandes, Catarina; Melro, Elodie; Magalhaes, Solange; Alves, Luis; Craveiro, Rita; Filipe, Alexandra; Valente, Artur J. M.; Martins, Gabriela; Antunes, Filipe E.; Romano, Anabela; Medronho, BrunoLignocellulosic biomass is a renewable and sustainable feedstock, mainly composed of cellulose, hemicellulose, and lignin. Lignin, as the most abundant natural aromatic polymer occurring on Earth, has great potential to produce value-added products. However, the isolation of highly pure lignin from biomass requires the use of efficient methods during lignocellulose fractionation. Therefore, in this work, novel acidic deep eutectic solvents (DESs) were prepared, characterized and screened for lignin extraction from maritime pine wood (Pinus pinaster Ait.) sawdust. The use of cosolvents and the development of new DES were also evaluated regarding their extraction and selectivity performance. The results show that an 1 h extraction process at 175 ?C, using a novel DES composed of lactic acid, tartaric acid and choline chloride, named Lact:Tart:ChCl, in a molar ratio of 4:1:1, allows the recovery of 95 wt% of the total lignin present in pine biomass with a purity of 89 wt%. Such superior extraction of lignin with remarkable purity using a ?green? solvent system makes this process highly appealing for future large-scale applications. ? 2021 Elsevier B.V. All rights reserved.
- On hair care physicochemistry: From structure and degradation to novel biobased conditioning agentsPublication . Fernandes, Catarina; Medronho, B.; Alves, Luís; Rasteiro, Maria GraçaHair is constantly exposed to various adverse external stimuli, such as mechanical or thermal factors, that may cause damage or cause it to lose its shine and smooth appearance. These undesirable effects can be minimized by using hair conditioners, which repair the hair and restore the smooth effect desired by the consumer. Some of the currently used conditioning agents present low biodegradability and high toxicity to aquatic organisms. Consumers are also becoming more aware of environmental issues and shifting their preferences toward natural-based products. Therefore, developing novel, sustainable, natural-based derivatives that can act as conditioning agents in hair care products and thus compete with the traditional systems obtained from non-renewable sources is highly appealing. This paper presents the key physicochemical aspects of the hair conditioning process, including hair structure and degradation, and reviews some of the new alternative conditioning agents obtained from natural resources.