Experiências didáticas para o ensino da física da 10º ano escolaridade

Dissertação de mestrado em Ciências – Formação Contínua de Professores (área de especialização em Física e Química)O presente trabalho pretende ser um contributo para o ensino experimental da Física do 10.º ano de escolaridade, tendo como tema de fundo a Energia. Procurou-se desenvolver um conjunto de experiências didáticas demonstrativas, diversificadas e contextualizadas historicamente, defendendo-se que, se a educação em ciências pretende que o aluno compreenda o mundo físico, perceba e utilize o conhecimento conceptual e processual que os cientistas desenvolveram para os auxiliar nessa tarefa, uma parte importante é, então, a familiarização com esse mundo. Não se advoga uma abordagem da ciência como um conjunto de invenções e descobertas individuais, herméticas e fixas, limitando-se a expor as ideias centrais das teorias e suas aplicações imediatas sem considerar o processo subjacente à construção dessas hipóteses, mas a adoção de uma perspectiva dinâmica, podendo ser uma ferramenta útil para a formação de alunos críticos e com capacidade de reflexão. Não se pretende uma postura passiva por parte dos alunos, mas sim permitir que estes se coloquem no papel de cientistas: discutindo, desenvolvendo hipóteses, projetando novas experiências, prevendo resultados e regressando para novas hipóteses e mais atividades, projetadas por eles. Pretende-se uma aprendizagem ativa, onde as atividades mostrem o que acontece e por que acontece. Cada protótipo está devidamente enquadrado em termos dos conteúdos abordados no 10.º ano do ensino secundário. Apresenta-se o princípio subjacente ao seu funcionamento, bem como sugestões didáticas para a sua aplicação. A descrição das várias etapas de construção dos protótipos das atividades propostas permite a sua concretização pelos professores. Pretende-se demonstrar que é possível a construção e exploração de montagens experimentais feitas com materiais do dia-a-dia, acessíveis a qualquer Escola, com procedimentos de construção simples.This work wants to be a contribution to the experimental teaching of Physics for the 10th grade, having the theme “Energy” as topic idea. The work was designed in order to develop a set of didactic experiments, historically defined, assuming that, if the education for sciences wants the student to understand the physical world and to use the conceptual and procedural knowledge that the scientists have developed to assist them in that task, then it is important for them to become familiar with that world. It doesn’t defend an approach to science as a group of individual inventions and discoveries, tight and immutable, just exposing the central ideas of theories and their immediate application without considering the underlying process which was the basis for the construction of the same hypothesis – it adopts a dynamic perspective and thus it can be a useful tool for the training of critical and reflective capacities in students. Students are not expected to be passive; rather, it is anticipated that they act as scientists: discussing, developing hypothesis, projecting new experiments, predicting results and going back to new hypotheses and further activities planned by them. It is intended that students have a proactive learning, where activities show what happens and why it happens. Each prototype is duly set in the curricula of the 10th grade of Secondary education. The underlying principle of how it works and the didactic suggestions of its application are presented. Furthermore, the description of the several stages of construction of the prototypes allows them to be made real by the teachers. It is meant to demonstrate that it is possible to build and explore experimental sets made with every day materials that any school can purchase and build

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Heterogeneous contributions of change in population distribution of body mass index to change in obesity and underweight NCD Risk Factor Collaboration (NCD-RisC)

From 1985 to 2016, the prevalence of underweight decreased, and that of obesity and severe obesity increased, in most regions, with significant variation in the magnitude of these changes across regions. We investigated how much change in mean body mass index (BMI) explains changes in the prevalence of underweight, obesity, and severe obesity in different regions using data from 2896 population-based studies with 187 million participants. Changes in the prevalence of underweight and total obesity, and to a lesser extent severe obesity, are largely driven by shifts in the distribution of BMI, with smaller contributions from changes in the shape of the distribution. In East and Southeast Asia and sub-Saharan Africa, the underweight tail of the BMI distribution was left behind as the distribution shifted. There is a need for policies that address all forms of malnutrition by making healthy foods accessible and affordable, while restricting unhealthy foods through fiscal and regulatory restrictions

SARS-CoV-2 Omicron is an immune escape variant with an altered cell entry pathway

Vaccines based on the spike protein of SARS-CoV-2 are a cornerstone of the public health response to COVID-19. The emergence of hypermutated, increasingly transmissible variants of concern (VOCs) threaten this strategy. Omicron (B.1.1.529), the fifth VOC to be described, harbours multiple amino acid mutations in spike, half of which lie within the receptor-binding domain. Here we demonstrate substantial evasion of neutralization by Omicron BA.1 and BA.2 variants in vitro using sera from individuals vaccinated with ChAdOx1, BNT162b2 and mRNA-1273. These data were mirrored by a substantial reduction in real-world vaccine effectiveness that was partially restored by booster vaccination. The Omicron variants BA.1 and BA.2 did not induce cell syncytia in vitro and favoured a TMPRSS2-independent endosomal entry pathway, these phenotypes mapping to distinct regions of the spike protein. Impaired cell fusion was determined by the receptor-binding domain, while endosomal entry mapped to the S2 domain. Such marked changes in antigenicity and replicative biology may underlie the rapid global spread and altered pathogenicity of the Omicron variant

Involvement of Th1Th17 Cell Subpopulations in the Immune Responses of Mothers Who Gave Birth to Children with Congenital Zika Syndrome (CZS)

High levels of T helper 17 cell (Th17)-related cytokines have been shown in acute Zika virus (ZIKV) infection. We hypothesized that the high levels of Th17-related cytokines, associated with a regulatory environment during pregnancy, create a favorable milieu for the differentiation of CD4+Th17 cells. We present data from a cross-sectional study on mothers who confirmed ZIKV infection by qRT-PCR and their children. We also recruited non-pregnant women infected with ZIKV in the same period. ZIKV infection occurred between 2015 and 2017. We collected samples for this study between 2018 and 2019, years after the initial infection. We highlight that, after in vitro stimulation with ZIKV CD4 megapool (ZIKV MP), we found a lower frequency of IL-17-producing CD4+ T cells (Th17), especially in the mothers, confirmed by the decrease in IL-17 production in the supernatant. However, a higher frequency of CD4+ IL-17+ IFN-γ+ T cells (Th1Th17) responding to the ZIKV MP was observed in the cells of the mothers and children but not in those of the non-pregnant women. Our data indicate that the priming of CD4 T cells of the Th1Th17 phenotype occurred preferentially in the mothers who gave birth to children with CZS and in the children

Evaluation of the Expression of CCR5 and CX3CR1 Receptors and Correlation with the Functionality of T Cells in Women infected with ZIKV during Pregnancy

There have been reports of neurological abnormalities associated with the Zika virus (ZIKV), such as congenital Zika syndrome (CZS) in children born to mothers infected during pregnancy. We investigated how the immune response to ZIKV during pregnancy is primed and conduct a thorough evaluation of the inflammatory and cytotoxic profiles as well as the expression of CCR5 and CX3CR1. We compared the reactivity of T cells to ZIKV peptides in convalescent mothers infected during pregnancy. The child’s clinical outcome (i.e., born with or without CZS) was taken to be the variable. The cells were stimulated in vitro with ZIKV peptides and evaluated using the ELISPOT and flow cytometry assays. After in vitro stimulation with ZIKV peptides, we observed a tendency toward a higher Interferon gamma (IFN-γ)-producing T cell responses in mothers who had asymptomatic children and a higher CD107a expression in T cells in mothers who had children with CZS. We found a higher frequency of T cells expressing CD107a+ and co-expressing CX3CR1+CCR5+, which is much clearer in the T cells of mothers who had CZS children. We suggest that this differential profile influenced the clinical outcome of babies. These data need to be further investigated, including the evaluation of other ZIKV peptides and markers and functional assays

Evaluation of the Expression of CCR5 and CX3CR1 Receptors and Correlation with the Functionality of T Cells in Women infected with ZIKV during Pregnancy

There have been reports of neurological abnormalities associated with the Zika virus (ZIKV), such as congenital Zika syndrome (CZS) in children born to mothers infected during pregnancy. We investigated how the immune response to ZIKV during pregnancy is primed and conduct a thorough evaluation of the inflammatory and cytotoxic profiles as well as the expression of CCR5 and CX3CR1. We compared the reactivity of T cells to ZIKV peptides in convalescent mothers infected during pregnancy. The child’s clinical outcome (i.e., born with or without CZS) was taken to be the variable. The cells were stimulated in vitro with ZIKV peptides and evaluated using the ELISPOT and flow cytometry assays. After in vitro stimulation with ZIKV peptides, we observed a tendency toward a higher Interferon gamma (IFN-γ)-producing T cell responses in mothers who had asymptomatic children and a higher CD107a expression in T cells in mothers who had children with CZS. We found a higher frequency of T cells expressing CD107a+ and co-expressing CX3CR1+CCR5+, which is much clearer in the T cells of mothers who had CZS children. We suggest that this differential profile influenced the clinical outcome of babies. These data need to be further investigated, including the evaluation of other ZIKV peptides and markers and functional assays