Engineering elliptical spin-excitations by complex anisotropy fields in Fe adatoms and dimers on Cu(111)

We investigate the dynamics of Fe adatoms and dimers deposited on the Cu(111) metallic surface in the presence of spin-orbit coupling, within time-dependent density functional theory. The \textit{ab initio} results provide material-dependent parameters that can be used in semiclassical approaches, which are used for insightful interpretations of the excitation modes. By manipulating the surroundings of the magnetic elements, we show that elliptical precessional motion may be induced through the modification of the magnetic anisotropy energy. We also demonstrate how different kinds of spin precession are realized, considering the symmetry of the magnetic anisotropy energy, the ferro- or antiferromagnetic nature of the exchange coupling between the impurities, and the strength of the magnetic damping. In particular, the normal modes of a dimer depend on the initial magnetic configuration, changing drastically by going from a ferromagnetic metastable state to the antiferromagnetic ground state. By taking into account the effect of the damping into their resonant frequencies, we reveal that an important contribution arises for strongly biaxial systems and specially for the antiferromagnetic dimers with large exchange couplings. Counter intuitively, our results indicate that the magnetic damping influences the quantum fluctuations by decreasing the zero-point energy of the system

The influence of music in the development of phonetics, phonology and phonological awareness in 3-year-olds with typical development and 3- to 6-year-olds with speech or language disorder

The relation between music and language has been intensively studied in recent years. Research has revealed that both domains engage similar processing mechanisms, including auditory processing and higher cognitive functions, and recruite partially overlapping brain structures. Furthemore, different authors have shown that linguistic functions can be positively influenced by music training above 4 years old. Music has also been shown to be associated with the promotion of linguistics skills in children with specific pathologies related to language, such as dyslexia, in 7- to 10-year-olds. In this thesis, we conducted four studies on the effect of music training on different aspects of language development. We studied this influence on phonological awareness in children with typical development and speech or language disorder (Studies 1 and 2) and on phonetic and phonological development in the same populations (Studies 3 and 4). In this randomized control study, with a test-training-retest methodology, 49 typically developing children, aged between 3 and 4, were assessed with a phonological awareness test (Study 1) and a phonetic and phonological test (Study 3). These tests were applied before and after a school year with weekly Music Classes (experimental group) or Visual Arts Classes (control group) in kindergarten. Two additional studies with the same methodology were conducted with 16 atypically developing children, aged between 3 and 6. This group included children with phonologically based Speech Sound Disorder (SSD) and / or Developmental Language Disorder (DLD). The goal of investigating this topic in this group of atypical children was to understand music relation with phonological awareness development (Study 2) and phonetic and phonological development (Study 4), and this at stages earlier than those where the beneficial effect of music in language-related skills has already been found. When comparing pre- and post-assessment and irrespective of type of lessons’ exposure (music or visual arts), results always showed significant differences in each group, as expected due to general developmental reasons. In Study 1, Music Classes’ students outperformed the control group, showing significantly larger differences between the beginning and the end of the lessosns period, indicating that music lessons have influenced phonological awareness, and pointing to a causal relation between music training and phonological awareness as soon as 3 years of age. In Studies 2, 3 and 4 no significant differences were found between groups in the post-assessment moment. This fact may suggest the need of more intensive music training or, in what concerns atypically developing children, a specific music curriculum designed to bridge their linguistic rhythm (and possibly pitch) processing deficits. Globally, this thesis supports the hypothesis that music training may promote language abilities, in particular phonological awareness, in 3-year-olds with typical development, that is prior to the ages that have been previously studied.A relação entre música e linguagem tem sido alvo de diversos estudos ao longo dos últimos anos. Estes estudos têm demonstrado que as duas áreas estão relacionadas, utilizando mecanismos de processamento comuns (incluindo o processamento auditivo e o processamento de funções cognitivas) e recorrendo a estruturas neuronais comuns. Vários autores referem a influência da música em diferentes áreas do desenvolvimento linguístico em crianças com idades superiores a 4 anos, nomeadamente no que diz respeito a competências de consciência fonológica, consciência fonémica, precursores da leitura e capacidade de leitura (em crianças com desenvolvimento típico e com dislexia). De forma a compreender a influência do treino musical no desenvolvimento da consciência fonológica (Estudos 1 e 2) bem como das capacidades fonéticas e fonológicas da criança (Estudos 3 e 4), foi desenhado um estudo com metologia teste-treino-reteste, com randomização de uma amostra e constituição de um grupo com Aulas de Música (grupo experimental) e outro grupo com Aulas de Artes Visuais (grupo de controlo). Esta metodologia incidiu sobre uma população de crianças com desenvolvimento típico (N=49), com 3 anos de idade (Estudos 1 e 3) e sobre uma população com Perturbação de Sons de Fala de base fonológica e / ou Perturbação do Desenvolvimento da Linguagem (N=16), entre os 3 e os 6 anos de idade (Estudos 2 e 4). Todas as crianças foram avaliadas antes e depois do período de intervenção, que decorreu durante um ano escolar, em contexto de Jardim de Infância, com a frequência de uma aula semanal de 45 minutos (Música VS Artes Visuais). A comparação realizada entre os momentos de avaliação inicial e final revelou diferenças significativas no desenvolvimento das diversas competências, em todos os grupos – melhoria expectável devido ao desenvolvimento da criança resultante apenas do tempo decorrido. No Estudo 1, sobre a influência da música no desenvolvimento da Consciência Fonológica, os alunos de Música obtiveram melhores resultados do que os alunos de Artes Visuais, mostrando uma evolução significativamente maior do que o grupo de controlo no momento da pós-avaliação. Este facto indica que o treino musical influenciou positivamente o desenvolvimento das competências de consciência fonológica, apontando para uma relação de causa-efeito, aos 3 anos de idade. Nos Estudos 2 (influência da música no desenvolvimento da consciência fonológica em crianças com desenvolvimento atípico), 3 (influência da música no desenvolvimento fonético-fonológico em crianças com desenvolvimento típico) e 4 (influência da música no desenvolvimento fonético-fonológico em crianças com desenvolvimento atípico) não foram encontradas diferenças significativas entre os grupos experimentais e de controlo no momento de avaliação final. Este facto pode indicar a necessidade de um treino musical mais intensivo ou, no caso das crianças com desenvolvimento atípico, que compreenda um currículo especificamente desenhado para colmatar as dificuldades ao nível do processamento linguístico e musical. Esta tese suporta a hipótese de que o treino musical promove o desenvolvimento de capacidades linguísticas, nomeadamente de consciência fonológica, aos 3 anos de idade, numa faixa etária anterior às até aqui estudadas. Este facto poderá ter impacto na criação de programas de promoção da consciência fonológica em contexto de Jardim de Infância, ou na potenciação de estratégias utilizadas pelo educador de infância, no seu dia-a-dia, no sentido de promover o desenvolvimento de competências fundamentais nas aprendizagens subsequentes da leitura e da escrita

Impurity-induced orbital magnetization in a Rashba electron gas

We investigate the induced orbital magnetization density in a Rashba electron gas with magnetic impurities. Relying on classical electrodynamics, we obtain this quantity through the bound currents composed of a paramagnetic and a diamagnetic-like contribution which emerge from the spin-orbit interaction. Similar to Friedel charge ripples, the bound currents and the orbital magnetization density oscillate as function of distance away from the impurity with characteristic wavelengths defined by the Fermi energy and the strength of the Rashba spin-orbit interaction. The net induced orbital magnetization was found to be of the order of magnitude of its spin counterpart. Besides the exploration of the impact of the electronic filling of the impurity states, we investigate and analyze the orbital magnetization induced by an equilateral frustrated trimer in various non-collinear magnetic states. On the one hand, we confirm that non-vanishing three-spin chiralities generate a finite orbital magnetization density. On the other hand, higher order contributions lead to multiple-spin chiralities affecting non-trivially and significantly the overall magnitude and sign of the orbital magnetization

Sistemas de Ventilação Natural/Mistos em Edifícios de Habitação. Implicações Construtivas

A eficiência energética dos edifícios é uma preocupação comum dos países da União Europeia tendo em atenção os compromissos do protocolo de Quioto, a dependência energética da Europa e o carácter limitado dos combustíveis fosseis. Caminha-se para a limitação dos consumos de energia e para a certificação energética de todos os edifícios ou fracções. A ventilação, se por um lado constitui uma parcela significativa das perdas térmicas, no período de Inverno, o que conduz a uma necessidade de minimizar os caudais, por outro, é absolutamente necessária para assegurar caudais que garantam a qualidade do ar interior, a segurança dos utilizadores e o controlo dos riscos de condensações. A prática construtiva corrente tem evoluído no sentido de se melhorar a permeabilidade ao ar das caixilharias e da instalação de dispositivos nas cozinhas e instalações sanitárias que, muitas vezes, não garantem o número mínimo de renovações de ar necessárias. Nesta comunicação pretende-se reflectir sobre as exigências de conforto higrotérmico e sua ligação com a ventilação, bem como sobre as implicações construtivas da implementação de sistemas de ventilação natural/mistos em edifícios de habitação

Teachers' and students' views and attitudes towards a new mathematics curriculum: A case study

The education system in Portugal is in the midst of a period of intensive reform. This paper describes the findings of a qualitative case study focusing on the views and attitudes of teachers and students participating in a pilot curriculum development programme stressing active methodologies and group work, conducted by the Ministry of Education In particular it discusses their views and attitudes about mathematics, mathematics teaching and curriculum innovation. The teachers were found to struggle with a contradiction: whilst they approved the new orientations, which were seen as adequate and innovative, they complained strongly about the design and implementation of the programme Students had a generally positive attitude towards mathematics, although there were differences among them. The 7th graders were satisfied with their mathematics classes and with the new curriculum. The 10th graders did not consider the changes as significant in themselves, but expressed concern for their academic progress

Emergent social NPC interactions in the Social NPCs Skyrim mod and beyond

This work presents an implementation of a social architecture model for authoring Non-Player Character (NPC) in open world games inspired in academic research on agentbased modeling. Believable NPC authoring is burdensome in terms of rich dialogue and responsive behaviors. We briefly present the characteristics and advantages of using a social agent architecture for this task and describe an implementation of a social agent architecture CiF-CK released as a mod Social NPCs for The Elder Scrolls V: SkyrimComment: Originally a chapter for Game AI Pro, contains 14 pages, 3 figure

Dynamical amplification of magnetoresistances and Hall currents up to the THz regime

Spin-orbit-related effects offer a highly promising route for reading and writing information in magnetic units of future devices. These phenomena rely not only on the static magnetization orientation but also on its dynamics to achieve fast switchings that can reach the THz range. In this work, we consider Co/Pt and Fe/W bilayers to show that accounting for the phase difference between different processes is crucial to the correct description of the dynamical currents. By tuning each system towards its ferromagnetic resonance, we reveal that dynamical spin Hall angles can non-trivially change sign and be boosted by over 500%, reaching giant values. We demonstrate that charge and spin pumping mechanisms can greatly magnify or dwindle the currents flowing through the system, influencing all kinds of magnetoresistive and Hall effects, thus impacting also dc and second harmonic experimental measurements.Comment: 19 pages, 4 figures, Supplementary Informatio

Measuring valley polarization in two-dimensional materials with second-harmonic spectroscopy

A population imbalance at different valleys of an electronic system lowers its effective rotational symmetry. We introduce a technique to measure such imbalance - a valley polarization - that exploits the unique fingerprints of this symmetry reduction in the polarization-dependent second-harmonic generation (SHG). We present the principle and detection scheme in the context of hexagonal two-dimensional crystals, which include graphene-based systems and the family of transition metal dichalcogenides, and provide a direct experimental demonstration using a 2H-MoSe$_{2}$ monolayer at room temperature. We deliberately use the simplest possible setup, where a single pulsed laser beam simultaneously controls the valley imbalance and tracks the SHG process. We further developed a model of the transient population dynamics which analytically describes the valley-induced SHG rotation in very good agreement with the experiment. In addition to providing the first experimental demonstration of the effect, this work establishes a conceptually simple, com-pact and transferable way of measuring instantaneous valley polarization, with direct applicability in the nascent field of valleytronics

A new architecture for intelligent clinical decision support for intensive medicine

Real-time and intelligent decision support systems are of most importance to supply intensive care professionals with important information in useful time. The work presented hereby shows an architectural overview of the communication system with bedside devices such as vital sign monitors. Intelligent Decision Support System for Intensive Medicine (ICDS4IM) goal is to ensure information quality and availability to Intensive Medicine professionals to take supported decisions in a mutable environment where complex and unpredictable events are a common state. Therefore, this work focus on Health Information Systems, Interoperability and Information Diffusion and Archive. Moreover, communication standards and the usage of a new technology such as containerization are discussed. (C) 2020 The Authors. Published by Elsevier B.V.The work has been supported by FCT - Fundacao para a Ciencia e Tecnologia within the Projects Scope: UID/CEC/00319/2020 and DSAIPA/DS/0084/2018