Seeking one's heading through eye movements

A study of eye movements during simulated travel toward a grove of four stationary trees revealed that observers looked most at pairs of trees that converged or decelerated apart. Such pairs specify that one's direction of travel, called heading, is to the outside of the near member of the pair. Observers looked at these trees more than those that accelerated apart; such pairs do not offer trustworthy heading information. Observers also looked at gaps between trees less often when they converged or diverged apart, and heading can never be between such pairs. Heading responses were in accord with eye movements. In general, if observers responded accurately, they had looked at trees that converged or decelerated apart; if they were inaccurate, they had not. Results support the notion that observers seek out their heading through eye movements, saccading to and fixating on the most informative locations in the field of view.

Stochastic Stability for Markovian Jump Linear Systems Subject to a Crucial Failure Event

This paper is concerned with the stability of discrete-time linear systems subject to random jumps in the parameters, described by an underlying finite-state Markov chain. In the model studied, a stopping time τ Δ is associated with the occurrence of a crucial failure after which the system is brought to a halt for maintenance. The usual stochastic stability concepts and associated results are not indicated, since they are tailored to pure infinite horizon problems. Using the concept named stochastic τ-stability, equivalent conditions to ensure the stochastic stability of the system until the occurrence of τ Δ is obtained. In addition, an intermediary and mixed case for which τ represents the minimum between the occurrence of a fix number N of failures and the occurrence of a crucial failure τ Δ is also considered. Necessary and sufficient conditions to ensure the stochastic τ-stability are provided in this setting that are auxiliary to the main result.

Strengthening development: the interplay of macro- and microeconomics

Includes bibliography

Methodology for the comparison of military expenditures

Includes bibliography

In search of work. International migration of women in Latin America and the Caribbean. Selected bibliography

Includes bibliography

Mnitoramento do desenvolvimento infantil realizado no Brasil

Objective: To review scientific literature in order to check how infant development surveillance is being carried out in Brazil. Data sources: Search on databases (PubMed, Medline, SciELO and CAPES Database Thesis) for studies on medical practices related to surveillance and monitoring of child development in Brazil from 2000 to 2011. The terms used for research were: child development surveillance, early intervention, developmental screening, and developmental screening tests. There were ten texts on the subject under study. Original articles, reviews, and thesis were analyzed, as well as the reference lists of publications on the topic. Data synthesis: Studies on monitoring of child development in Brazil showed major failures from pediatrician formation to clinical practice. Conclusions: It is urgent to offer continued medical education to pediatricians in order to update their knowledge about child development monitoring, especially due to the increasing numbers of preterm infants.

Co-operativism and popular participation: new considerations regarding an old subject

Includes bibliography

Peircean semiotics and subject indexing: Contributions of speculative grammar and pure logic

The semiotics of C S. Peirce presents fundamental concepts to discover aspects of the indexing process, including representation and classes of signs. However, we still know little of its theoretical potential for subject indexing. We believe that the main difficulty in the proposals to understand the process of subject indexing based on Peircean semiotics stems from an incomplete interpretation of his semiotic system. This paper attempts to describe the contributions of Peircean semiotics to subject indexing. First, we analyze some of the concepts of the branches of semiotics, after which, we discuss strategies for conceptual approximation. Secondly, and aiming to raise the level of interlocution between the areas, we intend to argue that subject indexing is an inferential process, as explained by the second branch of semiotics. Thus, we seek to go beyond the level of speculative grammar, the first branch of semiotics, to forge a closer link with pure or critical logic, the second branch. We conclude that the indexer's work does not produce a mere reflection of what already exists in documents, but involves an instigating action to discover, through the inferential matrix, the meaning of a text in order to find the subject and the most appropriate subject added entry to the information system.

Population and development subject in the CELADE teaching programmes

Includes bibliography

Areas de estudio recomendadas por el Grupo de Expertos Africanos en Ciencia y Tecnología para el Desarrollo = Subject areas recommended by the African Experts Group on Science and Technology for Development

Documento Informativo, No 2