52 research outputs found
O efeito do esquecimento dirigido na inferência espontânea de traços
Dissertação de mestrado, Psicologia (Área de especialização em Cognição Social Aplicada), Universidade de Lisboa, Faculdade de Psicologia, 2021Inferências Espontâneas de Traço (IET) são o fenómeno através do qual nós inferimos traços
ao observar comportamentos e os associamos aos seus atores. O processamento automático
e inconsciente das IET’s já foi amplamente demonstrado, acontecendo até em situações em
que não há uma necessidade de inferências de traço ou elas são prejudiciais para quem as
faz. Mas a existência de algum tipo de controlo consciente sobre este processo é ainda uma
possibilidade em aberto e o Esquecimento Dirigido, um paradigma em que é pedido aos
participantes para esquecer conscientemente algum tipo de informação, pode ser uma das
melhores opções para promover esse controlo. Utilizando o Paradigma de Falsos
Reconhecimentos, foi testado o efeito do Esquecimento Dirigido nas Inferências
Espontâneas de Traço. Os resultados demonstraram que o Esquecimento Dirigido não inibiu
ou afetou significativamente a formação de Inferências Espontâneas de Traço. Os resultados
também demonstraram que a instrução para esquecer informação melhorou a capacidade de
os participantes indicarem corretamente se os traços alvo estavam presentes nessa
informação. A Fuzzy Trace Theory apresenta-se como a melhor explicação para estes
resultados. Futuras investigações deverão incluir uma medida da memória da informação
de forma a estudar melhor os efeitos do Esquecimento Dirigido e quão bem a Fuzzy Trace
Theory de facto os explica.Spontaneous Trait Inferences (STI) are the phenomenon through which we infer traits when
observing behaviours and bind them to their actors. STI’s automatic and unconscious
processing has been widely demonstrated, taking place even in situations where there isn’t
a need for trait inferences or they’re prejudicial for whoever is making them. But the
existence of some type of conscious control over this process is still an open possibility and
Directed Forgetting, a paradigm where the participants are asked to consciously forget some
type of information, might be one of the best chances to elicit such control. Using the False
Recognition Paradigm, the effect of Directed Forgetting on Spontaneous Trait Inferences
was tested. The results demonstrated that Directed Forgetting doesn’t inhibit or significantly
affect the formation of Spontaneous Trait Inferences. The results also demonstrated that the
instruction to forget information improved participants’ ability to correctly answer if the
target trait was present in that information. Fuzzy Trace Theory presents itself as the best
explanation for these results. Future research should include a measure of the memory of
the information to better study the Directed Forgetting effects and how well Fuzzy Trace
Theory does in fact explain them
Small-size MEMS accelerometer encapsulated in vacuum using Sigma-Delta modulation
A vacuum encapsulated MEMS accelerometer using Sigma-Delta modulation is here presented. Three different modulation orders (second, third, and fourth) were implemented in a field-programable gate array (FPGA), enabling flexibility for tuning the loop parameters in real-time. Three devices were measured, and the results are in good agreement with simulations performed in Simulink. A noise figure of 123 μg/√Hz for a bandwidth of 400 Hz and a range of at least ±1 g was experimentally measured. A figure of merit considering device size and bandwidth is proposed, highlighting the relevance of the results for the current state of the art.FCT - Fundação para a Ciência e a Tecnologia (PDE/BDE/114563/2016
In vitro assessment of the efficacy of a macrocyclic chelator in reversing methylmercury toxicity
PTDC/MED-FAR/31136/2017
UID/DTP/04138/2019
project REDE/1518/REM/2005
Norma Transitoria-DL57/2016/CP1376/CT002Methylmercury (MeHg) is a highly neurotoxic compound to which human populations are exposed via fish consumption. Once in cells, MeHg actively binds thiols and selenols, interfering with the activity of redox enzymes such as thioredoxin (Trx) and the selenoenzyme thioredoxin reductase (TrxR) which integrate the thioredoxin system. In fact, it has been shown that inhibition of this system by MeHg is a critical step in the unfolding of cell death. Current clinical approaches to mitigate the toxicity of MeHg rely on the use of chelators, such as meso-2,3-dimercaptosuccinic acid (DMSA) which largely replaced British anti-Lewisite or 2,3-dimercapto-1-propanol (BAL) as the prime choice. However, therapeutic efficacy is limited and therefore new therapeutic options are necessary. In this work, we evaluated the efficacy of a macrocyclic chelator, 1-thia-4,7,10,13-tetraazacyclopentadecane ([15]aneN4S), in preventing MeHg toxicity, namely by looking at the effects over relevant molecular targets, i.e., the thioredoxin system, using both purified enzyme solutions and cell experiments with human neuroblastoma cells (SH-SY5Y). Results showed that [15]aneN4S had a similar efficacy to DMSA and BAL in reversing the inhibition of MeHg over purified TrxR and Trx by looking at both the 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB) reduction assay and insulin reduction capability. In experiments with cells, none of the chelating agents could reverse the inhibition of TrxR by MeHg, which corroborates the high affinity of MeHg to the selenol in TrxR active site. [15]aneN4S and BAL, unlike DMSA, could prevent inhibition of Trx, which allows the maintenance of downstream functions, although BAL showed higher toxicity to cells. Overall these findings highlight the potential of using [15]aneN4S in the treatment of MeHg poisoning and encourage further studies, namely in vivo.publishersversionpublishe
Formar bem as mães para criar e educar boas crianças: as revistas portuguesas de educação familiar e a difusão da maternidade científica (1945-1958)
Este artigo tem como principal objetivo contribuir para a compreensão do processo de construção da maternidade científica em Portugal. Neste sentido, foi analisado um conjunto de artigos (n=628), publicados em revistas de educação familiar, entre 1945 e 1958. A análise realizada permitiu compreender que as revistas analisadas contribuem para a difusão da maternidade científica, ou seja, da ideia de que a aquisição de conhecimento científico sobre a criação e educação das crianças é elemento indispensável ao adequado exercício da função maternal. Observou-se, ainda, a existência de diferentes estratégias de educação para a maternidade, às quais está subjacente um elemento de classe, assim como diferentes níveis de adesão, por parte das mulheres, à concepção de maternidade científica
A Bacia do Algarve: Estratigrafia, Paleogeografia e Tectónica
A “Bacia do Algarve” corresponde, segundo a literatura científica tradicional, aos terrenos mesocenozóicos que orlam o Sul de Portugal, desde o Cabo de São Vicente ao rio Guadiana (~140km), penetrando irregularmente para o interior entre 3 km a 25 km, sobre terrenos de idade carbónica da Zona Sul Portuguesa.
O hiato, de aproximadamente 70 milhões de anos, materializado pela discordância angular entre as rochas sedimentares de tipo flysch do Carbónico, metamorfizadas e deformadas durante a orogenia varisca, e as rochas sedimentares continentais do Triásico inferior provável, separa dois ciclos de Wilson. Os sedimentos carbónicos metamorfizados resultam do empilhamento orogénico de um possível prisma de acrecção associado à orogenia varisca e ao fecho de um oceano paleozóico e formação da Pangeia,
enquanto que os sedimentos continentais triásicos resultam do fim do colapso e do arrasamento do orógeno varisco e início do estiramento continental que viriam a culminar com a separação das placas litosféricas África, Eurásia e América.Os sedimentos mais recentes do Mesozóico e os mais antigos bem datados do Cenozóico encontram-se separados por um outro hiato que ultrapassa ligeiramente os 70 milhões de
anos na área emersa. Este hiato resulta duma alteração tectónica radical no contexto onde nessa época geológica se inseria a Bacia do Algarve. Esta mudança, que ocorreu no fim do
Cenomaniano, resultou da rotação do vector de deslocamento da trajectória de África em relação à Eurásia, de aproximadamente NW-SE para SW-NE (segundo as coordenadas actuais, e.g. Dewey et al, 1989), poria termo ao regime distensivo e de bacia de tipo rifte na Bacia do Algarve, com o fim do regime transtensivo entre a região noroeste da
placa África e sudoeste da placa Eurásia e início da colisão
Rituximab versus tocilizumab in rheumatoid arthritis: synovial biopsy-based biomarker analysis of the phase 4 r4ra randomized trial
Patients with rheumatoid arthritis (RA) receive highly targeted biologic therapies without previous knowledge of target expression levels in the diseased tissue. Approximately 40% of patients do not respond to individual biologic therapies and 5–20% are refractory to all. In a biopsy-based, precision-medicine, randomized clinical trial in RA (R4RA; n = 164), patients with low/absent synovial B cell molecular signature had a lower response to rituximab (anti-CD20 monoclonal antibody) compared with that to tocilizumab (anti-IL6R monoclonal antibody) although the exact mechanisms of response/nonresponse remain to be established. Here, in-depth histological/molecular analyses of R4RA synovial biopsies identify humoral immune response gene signatures associated with response to rituximab and tocilizumab, and a stromal/fibroblast signature in patients refractory to all medications. Post-treatment changes in synovial gene expression and cell infiltration highlighted divergent effects of rituximab and tocilizumab relating to differing response/nonresponse mechanisms. Using ten-by-tenfold nested cross-validation, we developed machine learning algorithms predictive of response to rituximab (area under the curve (AUC) = 0.74), tocilizumab (AUC = 0.68) and, notably, multidrug resistance (AUC = 0.69). This study supports the notion that disease endotypes, driven by diverse molecular pathology pathways in the diseased tissue, determine diverse clinical and treatment–response phenotypes. It also highlights the importance of integration of molecular pathology signatures into clinical algorithms to optimize the future use of existing medications and inform the development of new drugs for refractory patients
SAT-Based Leximax Optimisation Algorithms
In several real-world problems, it is often the case that the goal is to optimise several objective functions. However, usually there is not a single optimal objective vector. Instead, there are many optimal objective vectors known as Pareto-optima. Finding all Pareto-optima is computationally expensive and the number of Pareto-optima can be too large for a user to analyse. A compromise can be made by defining an optimisation criterion that integrates all objective functions.
In this paper we propose several SAT-based algorithms to solve multi-objective optimisation problems using the leximax criterion. The leximax criterion is used to obtain a Pareto-optimal solution with a small trade-off between the objective functions, which is suitable in problems where there is an absence of priorities between the objective functions. Experimental results on the Multi-Objective Package Upgradeability Optimisation problem show that the SAT-based algorithms are able to outperform the Integer Linear Programming (ILP) approach when using non-commercial ILP solvers. Additionally, experimental results on selected instances from the MaxSAT evaluation adapted to the multi-objective domain show that our approach outperforms the ILP approach using commercial solvers
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