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Apresenta o pensamento de dez autores, vindos da literatura, da universidade, da igreja, da música, da psicanálise e do jornalismo que encaram, de forma diversa, a dureza da guerra e as aspirações à paz. Com argumentos complementares e até opostos entre si, apresentam bons motivos para o repúdio ético e moral dos combates no Iraque

The literature on individuals' ability to predict their own level of risk tolerance is scarce and presents divergent results. Utilizing both differential prediction models and logit models on a sample of 391 individuals in Portugal, this study demonstrates that respondents' gender play a crucial role in this predictive ability. Men tend to overestimate their level of risk tolerance, while women tend to believe they are less risk-tolerant than they actually are. Furthermore, the results reveal that men's ability to correctly predict their level of risk tolerance is significantly higher. Being a man implies a 20% higher probability of being consistent in this prediction compared to being a woman, even after controlling for a set of sociodemographic factors. The finding of a systematic inconsistency between measures of subjective and objective risk tolerance suggests that the choice between the two measures of risk propensity is not indifferent. Our findings have relevant implications in the fields of corporate finance, financial investment, and various other spheres of economic life.

Abstract
It is widely acknowledged that having efficient financial markets is paramount in the allocation of social resources to their most productive uses. This paper explores the informational efficiency of six of the most important African stock markets for indication of seasonal predictability in stock returns. The results reveal that all markets exhibited some kind of seasonal patterns. The prevalence of the phenomenon was higher in the Egyptian and Tunisian markets, suggesting the presence of inefficient prices. Surprisingly, the only advanced emerging market of the sample (South Africa) showed a relatively large number of anomalies. This paper also reports the existence of strong pre-holiday effects and turn-of-the-month effects in most of the markets under scrutiny. Moreover, this study is the first to document the presence of quarterly effects in African markets. Collectively, the evidence obtained highlights the opportunity for arbitrageurs to reap profits as well as the need of decision-makers to implement legal and regulatory reforms in the markets of the continent.

Neste artigo estamos tratando dos métodos explícitos Runge Kutta (LSERK) de alta ordem e baixo armazenamento, que são usados principalmente para a discretização temporal e são estáveis independentemente de sua precisão. O principal objetivo deste trabalho é comparar o RK tradicional com diferentes formas de métodos LSERK. Os experimentos numéricos indicam que tais métodos são altamente precisos e eficazes para propósitos numéricos. Também é mostrado o tempo de CPU e suas implicações na solução. O método é bem adequado para obter uma solução precisa de alta ordem para o problema escalar de segunda ordem do problema de valor inicial (IVP), como é discutido no presente artigo.

O presente artigo analisa estratégias de telejornais para tratar do aumento de indenizações por acidentes que envolvem usuários de motocicletas. Para embasar nossas reflexões, utilizamos a teoria construcionista ou newsmaking. Como objeto de pesquisa, consideramos uma reportagem da Rede Record(08/08/2017) e outra da Rede Globo (28/09/2017). Nessas reportagens, ocorre uma ampliação da perspectiva meramente factual das narrativas.

In the present work is described a simple minimal model set of ordinary differential system of equations for simulating the swarming behavior of preys under action of predators. Preys and predators are represented by a set of ODEs taking in account the Newtonian attraction-repulsion forces. The predators interacts with the preys through a Newtonian force, which is a nonconservative force (includes friction) that acts in the same direction for both agents. A perturbing force is introduced for the predators' dynamics in order to simulate its behavior among preys. The resulting system of ordinary differential equations is solved numerically by means of Runge-Kutta of fourth order and the dynamics are discussed in the present work as the swarm's ability to realistically avoid the predator. The main goal is to reproduce swarm behavior that has been observed in nature with the minimal and simple possible model of ODE system.

Neste artigo buscamos analisar o papel do Maranhão no contexto da Monarquia Católica. Esta análise será realizada a partir da História Conectada, com a intenção de observar essa fase da história do Maranhão por uma perspectiva global, visando nos afastar das ideias dicotômicas de centro e periferia, que sempre colocam essa parte do mundo numa perspectiva congelada, ou estereotipada.

In this paper, we examine the Portuguese stock market for indication of time-series momentum effects using a new historical financial dataset that covers about 120 years of data. We find strong time-series momentum effects that cannot be explained by conventional risk factors. The positive return continuation seems to last for a period of 12 months, being heavily concentrated at the first month. At longer investment horizons, returns tend to mean-revert. The market exhibited significant time-series momentum for all look-back and holding periods of 12 months or less. A strategy with a 1-month look-back period and a 12-month holding period is shown to be the most profitable yielding a Sharpe ratio roughly 5.4 times that generated by a passive strategy. Time-series momentum strategies tend to perform best during extreme up-market periods and deliver the worst returns during down markets. This suggests that the strategy may not offer significant diversification benefits. Our findings add to the evidence that time-series momentum effects are not a product of data mining and are difficult to reconcile with the assertion that stock markets follow a random walk.