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Viagem e utopia: os lugares da invenção literária em Helena Marques
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Mascaradas satíricas de un Luis Buñuel performer
Get PDFEl artículo se centra en el estudio del arte de acción avant la lettre realizado durante
los inicios de Luis Buñuel en España, y en relación con el proceso de realización
de los filmes Un chien andalou (Un perro andaluz, 1929), efectuado en París y Los
olvidados (1950), producido en la Ciudad de México DF. De hecho, se trata de unas
actuaciones extraordinarias relacionadas con la etnografía e ideología.The paper focuses on the study of action art avant la lettre carried out during the beginnings
of Luis Buñuel in Spain, and in relation to the process of the films Un chien andalou (An
Andalusian dog, 1929), made in Paris and Los olvidados (The forgotten, 1950), produced
in Mexico City DF. In fact, some extraordinary performances related to ethnography and
ideology.info:eu-repo/semantics/publishedVersio
El llano en llamas. Soledades trágicas y feminismos en el cine mexicano contemporáneo
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True parthenogenesis and female-biased sex ratios in Cicadomorpha and Fulgoromorpha (Hemiptera, Auchenorrhyncha)
Get PDFInsects are renowned for their remarkable diversity of reproductive modes. Among these, the largest non-holometabolous order, Hemiptera, stands out with one of the most diversified arrays of parthenogenesis modes observed among insects. Although there are extensive reviews on reproduction without fertilization in some hemipteran higher taxa, no such analysis has been conducted for the large suborders Fulgoromorpha (planthoppers) and Cicadomorpha (leafhoppers). In both groups, there are species that reproduce by true parthenogenesis, specifically thelytoky, and in Fulgoromorpha, there are species that reproduce by pseudogamy or, more specifically, sperm-dependent parthenogenesis. In this review paper, we give and discuss the only currently known examples of true parthenogenesis in Fulgoromorpha and Cicadomorpha, mainly from the planthopper family Delphacidae and the leafhopper family Cicadellidae. We analyze patterns of distribution, ecology, mating behavior, acoustic communication, and cytogenetic and genetic diversity of parthenoforms and discuss hypotheses about the origin of parthenogenesis in each case. We also highlight examples in which natural populations show a shift in sex ratio toward females and discuss possible causes of this phenomenon, primarily the influence of endosymbiotic bacteria capable of altering the reproductive strategies of the hosts. Our review is mainly based on studies in which the authors have participated.</jats:p
MALDI-TOF MS: a promising analytical approach to cancer diagnostics and monitoring
Get PDFCancer remains the second most common cause of death after cardiovascular diseases, accounting for nearly 10 million deaths in 2020. Although the incidence of cancer increases considerably with age, the cancer burden can also be reduced and have a high chance of cure through early detection, appropriate treatment, and care of patients. The development of high-throughput analytical approaches, like matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), contributes to identifying a pool of proteins/peptides as putative biomarkers for the early detection, diagnosis, and tumor progression. The purpose of the current review is to present an updated outline of recent proteome/peptidome research to establish putative cancer biomarkers using MALDI-TOF MS and highlight the applicability of statistical analysis in the oncology field. The pros and cons of MALDI-TOF MS application on cancer diagnostics and monitoring will be discussed, as well as compared with tandem mass spectrometry (MS/MS)-based proteomics (e.g., liquid chromatography–tandem mass spectrometry). In addition, pre-analytical (e.g., sample quality control) and analytical (e.g., sample pre-treatment, instrumental analytical conditions) properties that influence the robustness of MALDI-TOF MS data will be also discussed.</jats:p
Controlo por orientação de campo de um motor de indução para aplicação automotiva
Get PDFAtualmente existe uma preocupação crescente com a poluição atmosférica,
nomeadamente a emissão de gases de efeito estufa. Existe ainda uma crescente
preocupação com a utilização de combustíveis fósseis para a locomoção, combustíveis
esses provenientes de uma fonte limitada e não renovável. Assim sendo, é cada vez mais
importante procurar alternativas à utilização de veículos movidos a combustíveis fósseis.
Neste trabalho, procurou-se desenvolver um protótipo de um carro elétrico,
utilizando uma máquina assíncrona juntamente com a técnica de controlo por orientação
de campo do rotor, de modo a controlar o binário da máquina e, dessa forma, controlar a
velocidade do carro.
Em conjunto com a máquina assíncrona, utilizou-se um conversor trifásico
bidirecional, o qual foi controlado através de modulação por largura de impulso (PWM),
permitindo não só fornecer energia à máquina assíncrona a partir de uma bateria DC,
como também receber energia da máquina assíncrona quando esta opera como gerador,
travando assim o carro.
De modo a controlar a máquina assíncrona, implementou-se controladores PI
(Proporcional-Integral) para controlar as correntes direta e em quadratura, assim como
controlar o binário e o fluxo da máquina. Também foi implementado um controlador PI
para controlar a velocidade de rotação da máquina, permitindo assim a realização de
testes em laboratório.
O desempenho da máquina assíncrona, sendo controlada através de orientação de
campo do rotor, foi simulado na plataforma MATLAB/Simulink, onde foi analisado o
comportamento do motor e do carro, para situações de subida, descida e plano.
Por fim, implementou-se o controlo do motor na prática, onde foi possível
comprovar os resultados obtidos através das simulações, tendo sido possível verificar a
viabilidade da utilização de uma máquina assíncrona em conjunto com a técnica de
controlo por orientação de campo do rotor para propulsionar um carro.Nowadays there is a rising concern about atmospheric pollution, in particular the
emissions of greenhouse gases. It also exists a rising concern regarding the usage of fossil
fuels as an energy source for locomotion. This kind of energy source came from a source
that is limited and not renewable. With that in mind, it’s increasingly important to search
for alternatives for fossil fuel vehicles.
In this work, it was develop a prototype of an electric car using an asynchronous
machine controlled by a rotor field oriented control technique in such a way that made
possible to control the torque of the machine, therefore controlling the speed of the
vehicle.
Together with the asynchronous machine it was used a 3-phase bidirectional
converter, which was controlled by a pulse with modulation (PWM) technique, allowing
not only the supply of power to the electric machine but also charge the battery with the
power produced by the machine when it’s working as a generator, slowing the car down.
In order to control the asynchronous machine, it was implemented several PI
(Proportional-Integrator) controllers so that the currents were controlled, as well as the
torque and flux of the machine. It was also implemented a PI controller to control the
speed of the machine.
The performance of the asynchronous machine being controller by the rotor field
oriented control was simulated using MATLAB/Simulink, where it was analyzed the
behavior of the motor as well as the behavior of the car while going up, down and flat.
Lastly, it was implemented the machine control in practice, where it was possible
to verify the results obtained during simulations. It was also possible to verify the viability
of an asynchronous machine with rotor field oriented control to power a car
Relatório de estágio para obtenção do grau de mestre em Educação Pré-Escolar e Ensino do 1.º Ciclo do Ensino Básico
Get PDFO presente relatório de estágio tem como objetivo primordial a partilha e a reflexão
alusiva às experiências e aos conhecimentos adquiridos no decorrer das três práticas
pedagógicas desenvolvidas para a obtenção do grau de mestre em Educação Pré- Escolar
e Ensino do 1.º Ciclo do Ensino Básico.
Este encontra-se estruturado em duas partes, o enquadramento teórico e metodológico
que suporta toda a ação desenvolvida e a intervenção pedagógica que evidencia os
contextos e as atividades realizadas na Educação Pré-Escolar e no Ensino do 1.ºCiclo do
Ensino Básico, mais precisamente com o grupo da Sala dos Ursos no Auxílio Maternal
do Funchal e com a turma do 1ºA e do 3ºB na Escola Básica com Pré-Escolar e Creche
de Santo Amaro.
Considerando a importância de o docente assumir uma postura de investigador que
analisa, discute e reflete sobre a sua prática educativa com o objetivo de organizá-la
tornando o processo de ensino-aprendizagem contextualizado e significativo para os
alunos, foi desenvolvido, em cada prática pedagógica, um projeto de Investigação-Ação,
com o intuito de colmatar as problemáticas identificadas. Definiu-se e implementou-se,
assim, um conjunto de estratégias e atividades em torno das questões orientadoras:
“Como promover o desenvolvimento pessoal e social das crianças na Sala dos Ursos?”,
“Como criar ambientes propícios à motivação, concentração e atenção dos alunos no
processo de ensino e aprendizagem?” e “ Como promover as competências de escrita
dos alunos do 3ºB?”.
Assim, este relatório explana todas as reflexões, as aprendizagens, as experiências e os
conhecimentos adquiridos no decorrer da formação inicial para a docência, tendo em
consideração a importância do papel ativo das crianças e alunos no processo de ensino e
aprendizagem.This internship report aims primarily at sharing and reflecting on the experiences and
knowledge acquired during the three pedagogical practices developed to obtain the
master's degree in Pre-School Education and Primary School Teaching.
The report, is structured into two parts. The theoretical and methodological. These
frameworks support all the action developed and the pedagogical intervention that
highlights the contexts and activities carried out in Pre-School Education and Primary
School Teaching, more precisely with the Bears Room group in the Funchal Maternal Aid
and with the 1stA and 3rdB class in the Santo Amaro Pre-School and Nursery School.
Considering the importance of teachers assuming an investigative attitude that analyzes,
discusses and reflects on their educational practice in order to organize it, making the
teaching-learning process contextualized and meaningful for students, a Research-Action
project was developed in each pedagogical practice, with the aim of solving the problems
identified. A set of strategies and activities was defined and implemented around the
guiding questions: "How to promote the personal and social development of children in
the Bear Room?", "How to create environments conducive to motivation, concentration
and attention of students in the teaching and learning process?" and "How to promote the
writing skills of 3rdB students?
Thus, this report explains all the reflections, learning, experiences and knowledge
acquired during the initial training for teaching, taking into account the importance of the
active role of children and students in the teaching and learning process
Campo de tensão entre géneros em A história de uma Serva (1985) e Os testamentos (2019), de Margaret Atwood
Get PDFNesta investigação pretende-se fazer uma aprofundada análise das obras The Handmaid’s
Tale [A História de uma Serva] (1985) e The Testaments [Os Testamentos] (2019), da
escritora canadense Margaret Atwood, com o intuito de estudar o campo de tensão entre
os géneros feminino e masculino retratado nas obras. Perante uma distopia patriarcal,
Margaret Atwood dá-nos a conhecer uma perspetiva ficcional que é de todo imaginável,
onde testemunhamos o género feminino subjugado ao género masculino, na voz de uma
personagem que relata os acontecimentos do seu dia-a-dia. As duas obras em análise, que
surgiram num contexto histórico diferente, mas que seguem a mesma narrativa, desafiam
o leitor a refletir sobre o papel e a importância das mulheres na sociedade ficcionada nos
textos analisados e, consequentemente, na realidade social contemporânea. O sistema
ideológico refletido nos textos possibilita igualmente a análise de como o género
masculino intervém na ação, ou melhor, como as figuras masculinas estão relacionadas e
afetam as vidas das figuras femininas, por beneficiarem de maior poder. Procura-se
descrever e analisar de que modo, numa história fictícia, se refletem aspetos da realidade
cultural contemporânea pelo olhar da autora em questão, bem como a relação entre
géneros narrada e como esta resulta num campo de tensão através da representação de
conflito entre as figuras. Pretende-se evidenciar em que medida as duas obras em estudo
perpetuam o legado de Simone de Beauvoir na atualidade, isto é, quais as ideias e teses
apresentadas no seu livro O Segundo Sexo (1949) que se refletem nos textos de Margaret
Atwood e são recebidas pela modernidade.This investigation intends to make an in-depth analysis of the works The Handmaid's Tale
(1985) and The Testaments (2019), by the Canadian writer Margaret Atwood, in order to
study the tension field between the feminine and masculine genders portrayed in the
works. Faced with a patriarchal dystopia, Margaret Atwood introduces us to a fictional
perspective that is entirely imaginable, where we witness the female gender subjugated
to the male gender, in the voice of a character who reports the events of her day-to-day.
The two works under analysis, which emerged in a different historical context, but which
follow the same narrative, challenge the reader to reflect on the role and importance of
women in the fictional society in the analyzed texts and, consequently, in contemporary social reality. The ideological system reflected in the texts also makes it possible to
analyze how the male gender intervenes in the action, or rather, how male figures are
related and affect the lives of female figures, as they benefit from greater power. It seeks
to describe and analyze how, in a fictional story, aspects of contemporary cultural reality
are reflected through the eyes of the author in question, as well as the relationship between
narrated genres and how this results in a field of tension through the representation of
conflict between the figures. It is intended to show to what extent the two works under
study perpetuate Simone de Beauvoir's legacy today, that is, which ideas and theses
presented in her book The Second Sex (1949) are reflected in Margaret Atwood's texts
and are received by modernity
Polystyrene microplastic particles in the food chain. Characteristics and toxicity: a review
Get PDFPolystyrene (PS) is a crucial material for modern plastic manufacturers, but its widespread use and direct discard in the
environment severely affect the food chain. This review provides a detailed study on the impact of PS microplastics
(PS-MPs) on the food chain and the environment, including information on their mechanism, degradation process,
and toxicity. The accumulation of PS-MPs in organisms' different organs leads to various adverse reactions, such as re duced body weight, premature deaths, pulmonary diseases, neurotoxicity, transgenerational issues, oxidative stress,
metabolic alterations, ecotoxicity, immunotoxicity, and other dysfunctions. These consequences affect diverse ele ments in the food chain, spanning from aquatic species to mammals and humans. The review also addresses the
need for sustainable plastic waste management policies and technological developments to prevent the adverse im pacts of PS-MPs on the food chain. Additionally, it emphasizes the importance of developing a precise, flexible, and
effective methodology for extracting and quantifying PS-MPs in food, considering their characteristics like particle
size, polymer types, and forms. While several studies have focused on the toxicity of polystyrene microplastics (PSMPs) in aquatic species, further investigation is required to understand the mechanisms by which they are transferred
across multiple trophic levels. Therefore, this article serves as the first comprehensive review, examining the mecha nism, degradation process, and toxicity of PS-MPs. It presents an analysis of the current research landscape of PS MPs in the global food chain, providing insights for future researchers and governing organizations to adopt better ap proaches to managing PS-MPs and preventing their adverse impacts on the food chain. As far as we know this is the
first article on this specific and impactant topic
Estimation of Productivity and Above-Ground Biomass for Corn (Zea mays) via Vegetation Indices in Madeira Island
Get PDFThe advancement of technology associated with the field, especially the use of unmanned
aerial vehicles (UAV) coupled with multispectral cameras, allows us to monitor the condition of
crops in real time and contribute to the field of machine learning. The objective of this study was
to estimate both productivity and above-ground biomass (AGB) for the corn crop by applying
different vegetation indices (VIs) via high-resolution aerial imagery. Among the indices tested, strong
correlations were obtained between productivity and the normalized difference vegetation index
(NDVI) with a significance level of p < 0.05 (0.719), as well as for the normalized difference red edge
(NDRE), or green normalized difference vegetation index (GNDVI) with crop productivity (p < 0.01),
respectively 0.809 and 0.859. The AGB results align with those obtained previously; GNDVI and
NDRE showed high correlations, but now with a significance level of p < 0.05 (0.758 and 0.695).
Both GNDVI and NDRE indices showed coefficients of determination for productivity and AGB
estimation with 0.738 and 0.654, and 0.701 and 0.632, respectively. The use of the GNDVI and NDRE
indices shows excellent results for estimating productivity as well as AGB for the corn crop, both at
the spatial and numerical levels. The possibility of predicting crop productivity is an essential tool
for producers, since it allows them to make timely decisions to correct any deficit present in their
agricultural plots, and further contributes to AI integration for drone digital optimization.info:eu-repo/semantics/publishedVersio