Ongoing host-shift speciation in Plasmodium simium

Copyright © 2021 Elsevier Ltd. All rights reserved.Plasmodium simium, a malaria parasite that infects platyrrhine monkeys and humans in the New World, is nearly identical to Plasmodium vivax. Recent genomic comparative analyses of these sister species have identified elevated divergence in a gene that may underlie P. simium adaptation to non-human primates during its gradual speciation process.publishersversionpublishe

Art students: do they really draw what they know about the inner body?

The aim of the present study was to examine seven case studies and ascertain whether the imagos internalized by students of Fine Arts, a Young Person and an Elderly Person can be reworked, after the students have been submitted to a course in Anatomy. In the present study, we have combined two methods - gathering written responses and drawings - and examined what students know about the organs they drew and used a content analysis grid to evaluate the mental representation of the interior of the body of both profiles (Young Person and Elderly Person), before and after academic training (Anatomy classes). The preliminary data collected provided a prima facie scenario for the existence of at least one sequencial comulative progression in the development of the art students drawings. However further research is needed to establish the extent to which this finding might apply beyond the tasks assigned in the present protocol.info:eu-repo/semantics/publishedVersio

Adsorption equilibrium of fructose, glucose and sucrose for cationic resins in the sodium and potassium form

Separation of glucose from mixtures of fructose and sucrose in molasses is a major challenge in industrial sugar chromatographic separations. The efficiency of a chromatographic process is largely dependent on the adsorbent used. Sulfonated poly(styrene-co-divinylbenzene) (PS-DVB) ion exchange resins are the most frequently used for sugars separation, generally in a cationic form. The cation will complex with the hydroxyl group of the sugar leading to a selective adsorption according to the orientation of the hydroxyl group. Thus, the conformation of the sugar determines its relative affinity for the resin and its distribution coefficient. Consequently, fructose forms the more stable sugar-cation complex being preferentially adsorbed in the resin followed by glucose. Sucrose interacts very weakly with the cation and is partially or totally excluded from the resin matrix owing to its larger molecular size. The separation process is usually carried out at high temperatures. However, this implies high energy costs and an elevated level of hydrolysis. Adsorption isotherms of the sugars present in a mixture are a very important parameter for the selection of the adsorbent to be used in the chromatographic separation. Therefore, in this study, the adsorption isotherms of glucose, fructose and sucrose were determined for two resins of PS-DVB in the sodium and potassium forms. Potassium and sodium are the most recommended cations for the separation of sucrose, fructose and glucose. The sodium and potassium resins matrix used in this work consist in meshes of 500-600 μm and 290-350 μm, respectively. Solutions with single and multi-component mixtures of the three sugars were used at 25ºC and 40ºC. A static method was used to determine the equilibrium adsorptions: 3.5 mL of solutions with different sugar concentrations were added to a known amount of adsorvent. The mixture was held for 8h under agitation and a fixed temperature and a final concentration in equilibrium with resin was determined by HPLC. As expected, the results achieved showed that for all the conditions, fructose is the most adsorved sugar followed by glucose and sucrose. For both resins, the increase of temperature conducted to a decrease on the adsorption constant for all the sugars in the mono-component mixtures. Nevertheless, the adsorption in multi-component mixtures was not significantly affected by the temperature in the sodium resin, and regarding the potassium resin only a small increase in the adsorption was observed. Multi-component mixtures at 25 ºC showed a decrease in the adsorption as compared with mono-component mixtures. However, at 40ºC the adsorption observed for the multi-component mixtures was higher than the observed for the mono-component ones. The sugars that demonstrated lower selectivity values were fructose/glucose since these sugars have the same molecular weight. Sucrose/fructose selectivity showed a higher value when compared with sucrose/glucose because of the complex formed between fructose and the resin. This profile was found for both resins used, regardless of temperature. Selectivity of both resins decreased with the increase of the temperature values. Nevertheless, the selectivity obtained for the potassium resin was higher as compared to the selectivity obtained for the sodium resin. In sum, potassium resin appears to be the most suitable adsorvent and an operational temperature of 25 ºC showed the best results

Chemical characterization of Sambucus nigra L. flowers aqueous extract and its biological implications

The main goal of this study was to chemically characterize an aqueous S. nigra flower extract and validate it as a bioactive agent. The elderflower aqueous extraction was performed at different temperatures (50, 70 and 90 °C). The extract obtained at 90 °C exhibited the highest phenolic content and antiradical activity. Therefore, this extract was analyzed by GC-MS and HPLC-MS, which allowed the identification of 46 compounds, being quercetin and chlorogenic acid derivatives representative of 86% of the total of phenolic compounds identified in hydrophilic fraction of the aqueous extract. Naringenin (27.2%) was the major compound present in the lipophilic fraction. The antiproliferative effects of the S. nigra extract were evaluated using the colon cancer cell lines RKO, HCT-116, Caco-2 and the extracts antigenotoxic potential was evaluated by the Comet assay in RKO cells. The RKO cells were the most susceptible to S. nigra flower extract (IC50=1250 µg mL1). Moreover, the extract showed antimicrobial activity against Gram-positive bacteria, particularly Staphylococcus aureus and S. epidermidis. These results show that S. nigra-based extracts can be an important dietary source of bioactive phenolic compounds that contribute to health-span improving life quality, demonstrating their potential as nutraceutical, functional foods and/or cosmetic components for therapeutic purposes.This research was funded by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UIDB/04469/2020 unit and for Scientific Employment Stimulus 2017 (CEECIND/01507/2017) provided to Ana M. Sousa.info:eu-repo/semantics/publishedVersio

Magnetoliposomes containing calcium ferrite nanoparticles for applications in breast cancer therapy

Magnetoliposomes containing calcium ferrite (CaFe2O4) nanoparticles were developed and characterized for the first time. CaFe2O4 nanoparticles were covered by a lipid bilayer or entrapped in liposomes forming, respectively, solid or aqueous magnetoliposomes as nanocarriers for new antitumor drugs. The magnetic nanoparticles were characterized by UV/Visible absorption, XRD, HR-TEM, and SQUID, exhibiting sizes of 5.2 ± 1.2 nm (from TEM) and a superparamagnetic behavior. The magnetoliposomes were characterized by DLS and TEM. The incorporation of two new potential antitumor drugs (thienopyridine derivatives) specifically active against breast cancer in these nanosystems was investigated by fluorescence emission and anisotropy. Aqueous magnetoliposomes, with hydrodynamic diameters around 130 nm, and solid magnetoliposomes with sizes of ca. 170 nm, interact with biomembranes by fusion and are able to transport the antitumor drugs with generally high encapsulation efficiencies (70%). These fully biocompatible drug-loaded magnetoliposomes can be promising as therapeutic agents in future applications of combined breast cancer therapy.This research was funded by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding of CF-UM-UP (UID/FIS/04650/2013; UID/FIS/04650/2019), CQUM (UID/QUI/00686/2016; UID/QUI/00686/2019) and LA-26 (PEst-C/SAU/LA0026/2013), and through the research project PTDC/QUI-QFI/28020/2017 (POCI-01-0145-FEDER-028020), financed by FCT, European Fund of Regional Development (FEDER), COMPETE2020 and Portugal2020. The magnetic measurements were supported by projects UTAP-EXPL/NTec/0046/2017, NORTE-01-0145-FEDER-028538 e PTDC/FIS-MAC/29454/2017. The APC was also funded by FCT. B.D.C. acknowledges FCT for a PhD grant (SFRH/BD/141936/2018)

Mudanças climáticas e percepções de atores sociais no meio rural*

As percepções humanas sobre mudanças climáticas podem influenciar fortemente a construção e a condução de estratégias de adaptação. Este trabalho discute aspectos teóricos de fatores sócio-culturais relacionados aos impactos das mudanças climáticas, e um estudo de caso conduzido em Anchieta, Santa Catarina, sobre percepções dessas mudanças segundo diferentes atores do meio rural

Questions in Science textbooks: development and validation of a checklist

Questões são enunciadas que requerem uma resposta refletida e que desempenham diversas funções educativas, incluindo o despoletar novas aprendizagens. Neste caso, o seu uso enquadra-se na Aprendizagem Baseada na Resolução de Problemas (ABRP, do inglês, Problem-Based Learning, PBL), que coloca o aluno no centro dos processos de ensino e aprendizagem, atribuindo-lhe um papel ativo na aprendizagem de novo conhecimento. Atendendo à influência que os manuais exercem nas práticas de ensino, a questão que se coloca é a de saber em que medida as questões incluídas nos manuais escolares de Ciências podem fomentar um ensino orientado para a ABRP. Neste texto, descrever-se-á o processo de construção e validação de uma grelha de análise de questões incluídas em manuais escolares de Ciências com essa finalidade, apresentando-se não só essa grelha, mas também, a título ilustrativo, uma aplicação da mesma a um tópico de Ciências, 8º ano, abordado nas duas disciplinas desta área.Questions require a thoughtful answer and can play diverse educational roles, such as stimulating the learning of new knowledge, as is the case in Problem-Based Learning (PBL) contexts. In this context, the student is placed at the center of the teaching and learning processes and plays an active role in the learning of new knowledge. Bearing in mind the influence that textbooks exert on teaching practices, it is worthwhile questioning to which extent questions included in school science textbooks promote a PBL oriented teaching approach. This paper describes the development and validation of a checklist for analyzing the questions included in science textbooks. After introducing the checklist, an example of its application to a science unit assigned to two junior high school science courses (8th grade) is given, approaching the two disciplines in the area

Broadened T-cell Repertoire Diversity in ivIg-treated SLE Patients is Also Related to the Individual Status of Regulatory T-cells

Intravenous IgG (ivIg) is a therapeutic alternative for lupus erythematosus, the mechanism of which remains to be fully understood. Here we investigated whether ivIg affects two established sub-phenotypes of SLE, namely relative oligoclonality of circulating T-cells and reduced activity of CD4 + Foxp3+ regulatory T-cells (Tregs) reflected by lower CD25 surface density.Octapharma research funding; Fundação para a Ciência e a Tecnologia postdoctoral fellowships: (SFRH/BPD/20806/2004, SFRH/BPD/34648/2007); FCT Programa Pessoa travel grant

Global Women’s Breakfast (GWB): #UnidaspelaQuímica

Global Women’s Breakfast (GWB): #BoundbyChemistry. Global Women’s Breakfast is an initiative of the International Union of Pure and Applied Chemistry, aiming to give women scientists, from all over the world, the opportunity to know each other, communicating virtually and sharing their experiences. Many countries joined this initiative and Portugal was not an exception, with its participation already at the first Networking Breakfast in 2011, celebrating the year of the centenaries of Marie Curie Nobel Prize in Chemistry, the Portuguese Chemical Society and the Faculdade de Ciências da Universidade de Lisboa as well. The success of these networking breakfasts, involving students, young researchers, and scientists, encouraged its further organization in Portugal, annually since 2019. This article describes the interventions of Portuguese women scientists, coming from Institutions throughout Portugal, in the Global Women’s Breakfast as partners in their mission as scientists, creative and open to international collaborations. Global Women's Breakfast é uma iniciativa criada pela International Union of Pure and Applied Chemistry para dar oportunidade às mulheres cientistas de todo o mundo de se conhecerem, comunicando virtualmente e compartilhando as suas experiências. A adesão dos países foi muito elevada e Portugal não foi exceção, participando já no primeiro Networking Breakfast em 2011, Ano Internacional da Química, no qual se celebraram os centenários do Prémio Nobel da Química a Marie Curie, da Sociedade Portuguesa de Química e da Faculdade de Ciências da Universidade de Lisboa. O sucesso destes pequenos-almoços em rede, que envolvem estudantes, jovens investigadoras e cientistas, encorajou a continuação da participação de Portugal anualmente, desde 2019. Este artigo descreve a intervenção de mulheres cientistas portuguesas, pertencentes a instituições de Norte a Sul do país, no Global Women’s Breakfast, cúmplices na sua missão de cientistas, criativas e abertas à colaboração internacional