Export-driven adjustment in Portugal

Macroeconomic imbalances in the eurozone have decreased significantly since the beginning of the financial and economic crisis. In Portugal, the economic adjustment process is strongly being driven by growth in export activity. The recent improvement in price competitiveness has supported the positive export trend. However, there are structural challenges that limit the potential for growth in the tradable sector. To ensure that the adjustment process is sustainable, it needs to be backed up by targeted structural reforms. This article aims to contribute to the discussion about the reduction of macroeconomic imbalances in the eurozone by analysing the determinants of export growth in Portugal and the role played by the adjustment policies contained in the macroeconomic programme

The euro after its first decade: Weathering the financial storm and enlarging the euro area

The first decade of economic and monetary union in Europe (EMU) has been a huge success. EMU has significantly benefited its member countries and accelerated the European integration process. Imbalances within EMU - differences in growth, inflation, competitiveness, current account and budget balances - have, however, increased in the last 10 years and, with their economic implications, have become more evident in the global economic crisis. The euro has served as a shield during the crisis, and arguments that the crisis would lead to a breakup of the monetary union are neither new nor convincing. But there are lessons to be learned. Policies should be better coordinated among EMU members and structural reforms accelerated, the framework for the supervision of financial markets strengthened, and external representation streamlined. The crisis has also made the euro more attractive, and most EU countries that are not yet members of EMU are expected to join during the next decade

Electrophysiological and Behavioral Working Memory Differences Between Musicians and Non-Musicians

The current study is an examination of P300 differences between musicians and non-musician groups during a visual oddball task, in addition to behavioral subtests of the TOMAL-2 measuring visual and auditory working memory. Previous research has demonstrated higher amplitude P300 waveforms with shorter latencies of P300 onset in musician groups, indicating a more sensitive and accurate stimulus detection system. Fluctuations of P300 amplitude and latency activity near parietal areas have been used to quantify differences in updating processes of working memory possibly associated with differences in amounts of music experience. The current study is designed to partially replicate a method previously implemented by George and Coch (2011) in order to contribute to the body of research describing how music experience may be associated with differences in visual processing as well as auditory working memory. Behavioral data will be collected using six standardized subtest measures of the TOMAL-2, followed by event-related potential (ERP) recordings during a large and small circle visual oddball task. The current study hypothesizes musicians will score significantly higher on the TOMAL-2 and record shorter latency with higher P300 amplitudes associated with greater amounts of music experience in areas previously associated with working memory processing

Cryptanalysis of the multivariate encryption scheme EFLASH

Post-Quantum Cryptography studies cryptographic algorithms that quantum computers cannot break. Recent advances in quantum computing have made this kind of cryptography necessary, and research in the field has surged over the last years as a result. One of the main families of post-quantum cryptographic schemes is based on finding solutions of a polynomial system over finite fields. This family, known as multivariate cryptography, includes both public key encryption and signature schemes. The majority of the research contribution of this thesis is devoted to understanding the security of multivariate cryptography. We mainly focus on big field schemes, i.e., constructions that utilize the structure of a large extension field. One essential contribution is an increased understanding of how Gröbner basis algorithms can exploit this structure. The increased knowledge furthermore allows us to design new attacks in this setting. In particular, the methods are applied to two encryption schemes suggested in the literature: EFLASH and Dob. We show that the recommended parameters for these schemes will not achieve the proposed 80-bit security. Moreover, it seems unlikely that there can be secure and efficient variants based on these ideas. Another contribution is the study of the effectiveness and limitations of a recently proposed rank attack. Finally, we analyze some of the algebraic properties of MiMC, a block cipher designed to minimize its multiplicative complexity.Doktorgradsavhandlin

Auditory Reaction Time and Behavioral Working Memory Differences Between Musicians and Non-Musicians

Previous research investigating working memory functioning between musicians and non-musicians has demonstrated differences related to music experience in auditory reaction tasks. This body of research suggests music experience may be related to faster reaction times to auditory stimuli. In addition to reaction times recorded by clicking a mouse while listening to a tonal oddball, participants in the current study performed six subtests of the TOMAL-2, a standardized measure of working memory ability, documenting participants visual, auditory, and executive functioning modules of working memory. Our hypotheses are that means of performance on all three subtests of the TOMAL-2 will be higher in the musician group compared to non-musicians, and that musicians will, on average, record faster reaction times to various tonal difference conditions. Results of the current study will contribute to the understanding of differences in cognitive processing related to long-term music experience

A heart for fibrillin : spatial arrangement in adult wild-type murine myocardial tissue

Fibrillins are major constituents of microfibrils, which are essential components of the extracellular matrix of connective tissues where they contribute to the tissue homeostasis. Although it is known that microfibrils are abundantly expressed in the left ventricle of the heart, limited data are available about the presence of microfibrils in the other parts of the myocardial tissue and whether there are age or sex-related differences in the spatial arrangement of the microfibrils. This basic knowledge is essential to better understand the impact of fibrillin-1 pathogenic variants on the myocardial tissue as seen in Marfan related cardiomyopathy. We performed histological analyses on wild-type male and female murine myocardial tissue collected at different time-points (1, 3 and 6 months). Fibrillin-1 and -2 immunofluorescence stainings were performed on cross-sections at the level of the apex, the mid-ventricles and the atria. In addition, other myocardial matrix components such as collagen and elastin were also investigated. Fibrillin-1 presented as long fibres in the apex, mid-ventricles and atria. The spatial arrangement differed between the investigated regions, but not between age groups or sexes. Collagen had a similar broad spatial arrangement to that of fibrillin-1, whereas elastic fibres were primarily present in the atria and the vessels. In contrast to fibrillin-1, limited amounts of fibrillin-2 were observed. Fibrillin-rich fibres contribute to the architecture of the myocardial tissue in a region-dependent manner in wild-type murine hearts. This knowledge is helpful for future experimental set-ups of studies evaluating the impact of fibrillin-1 pathogenic variants on the myocardial tissue

Analysis of Multivariate Encryption Schemes: Application to Dob

In this paper, we study the effect of two modifications to multivariate public key encryption schemes: internal perturbation (ip), and Q_+. Focusing on the Dob encryption scheme, a construction utilising these modifications, we accurately predict the number of degree fall polynomials produced in a Gröbner basis attack, up to and including degree five. The predictions remain accurate even when fixing variables. Based on this new theory we design a novel attack on the Dob encryption scheme, which breaks Dob using the parameters suggested by its designers. While our work primarily focuses on the Dob encryption scheme, we also believe that the presented techniques will be of particular interest to the analysis of other big-field schemes

Estudo diagnóstico sobre a Educação Física nas escolas públicas

Objetivo desta pesquisa foi diagnosticar a prática da Educação Física Escolar, no Ensino Fundamental em Escolas Municipais e Estaduais da rede de ensino do município de Arroio do Sal - RS, no ano de dois mil e seis. Foram investigadas as seguintes variáveis: obrigatoriedade, objetivos do programa, atividades ministradas aos alunos, regularidade e composição das sessões, dispensa do aluno, sistema de avaliação, corpo docente, formação profissional, instalações, equipamentos e inovações. Ficou evidenciado que ainda existem problemas tais como a falta de professores graduados para atuarem nas séries iniciais, falta de espaço físico adequado e materiais para a prática da educação física. Também se observou que não são ministradas em nenhuma escola competições para portadores de necessidades especiais e que não há nenhum Coordenador específico na área de Educação Física no município. Conclui-se ao final desse trabalho de diagnóstico que a correção de alguns problemas, a manutenção e a melhoria das atividades programadas para a Educação Física é fundamental para o desenvolvimento da disciplina nas escolas da rede de ensino do município

Analysis of Multivariate Encryption Schemes: Application to Dob and C*

A common strategy for constructing multivariate encryption schemes is to use a central map that is easy to invert over an extension field, along with a small number of modifications to thwart potential attacks. In this work we study the effectiveness of these modifications, by deriving estimates for the number of degree fall polynomials. After developing the necessary tools, we focus on encryption schemes using the $C^*$ and Dobbertin central maps, with the internal perturbation (ip), and $Q_+$ modifications. For these constructions we are able to accurately predict the number of degree fall polynomials produced in a Gröbner basis attack, up to and including degree five for the Dob encryption scheme and four for $C^*$. The predictions remain accurate even when fixing variables. Based on this new theory we design a novel attack on Dob, which completely recovers the secret key for the parameters suggested by its designers. Due to the generality of the presented techniques, we also believe that they are of interest to the analysis of other big field schemes

Constructing and Deconstructing Intentional Weaknesses in Symmetric Ciphers

Deliberately weakened ciphers are of great interest in political discussion on law enforcement, as in the constantly recurring crypto wars, and have been put in the spotlight of academics by recent progress. A paper at Eurocrypt 2021 showed a strong indication that the security of the widely-deployed stream cipher GEA-1 was deliberately and secretly weakened to 40 bits in order to fulfill European export restrictions that have been in place in the late 1990s. However, no explanation of how this could have been constructed was given. On the other hand, we have seen the MALICIOUS design framework, published at CRYPTO 2020, that allows to construct tweakable block ciphers with a backdoor, where the difficulty of recovering the backdoor relies on well-understood cryptographic assumptions. The constructed tweakable block cipher however is rather unusual and very different from, say, general-purpose ciphers like the AES. In this paper, we pick up both topics. For GEA-1 we thoroughly explain how the weakness was constructed, solving the main open question of the work mentioned above. By generalizing MALICIOUS we -- for the first time -- construct backdoored tweakable block ciphers that follow modern design principles for general-purpose block ciphers, i.e., more natural-looking deliberately weakened tweakable block ciphers