Medical imaging is predominantly a visual field. In this context, prenatal ultrasound images assume intense social, ethical, and psychological significance by virtue of the subject they represent: the fetus. This feature, along with the sophistication introduced by three-dimensional ultrasound imaging that allows improved visualization of the fetus, has contributed to the common impression that prenatal ultrasound scans are like photographs of the fetus. In this article we discuss the consistency of such a comparison. First, we investigate the epistemic role of (...) both analogic and digital photographic images as visual information-providing representations holding a high degree of objectivity. Second, we examine the structure and process of production of ultrasound scans and argue that a comparison between two-dimensional ultrasound and photography is justified. This is in contrast to 3D ultrasound images that, due to the intensive mathematical processing involved in their production, present some structural issues that obfuscate their ontological and epistemic status. (shrink)

The methodology of Latin American economic structuralism has been generally interpreted as an implicit extension of classic French structuralism of Claude Lévi-Strauss and others, without careful examination of the methodological pronouncements of Latin American economists and social scientists. The present paper provides a detailed treatment of how Latin American structuralist methodology was formed between the 1950s and 1970s, with emphasis on Celso Furtado's views. Furtado was influenced by both C. Lévi-Strauss's and F. Braudel's apparently incompatible approaches to structure and (...) history. Furtado's suggested combination of structure and history was based on the use of economic models to interpret successive historical structures, plus the development of the notion of creativity as a link between structures and processes. It differed in some important aspects from the ‘historical-structural method’ usually associated with other Latin American authors such as Sunkel, and Cardoso and Faletto, built on ex.. (shrink)

The encounter between Socrates and Thrasymachus in Republic I is notoriously baffling. Most of what is said seems straightforward, and the issues at stake are ones of common concern, but the argument remains elusive. The purpose of this paper is to investigate the nature and grounds of this elusiveness, and to show that some of it can be dispelled by a sufficiently free-ranging exegesis that bears in mind the general character of Plato’s writing.

We show how a simple nonlinear dynamical system (the discrete quadratic iteration on the unit segment) can be the basis for modelling the embryogenesis process. Such an approach, even though being crude, can nevertheless prove to be useful when looking with the two main involved processes:i) on one hand the cell proliferation under successive divisions ii) on the other hand, the differentiation between cell lineages. We illustrate this new approach in the case of Caenorhabditis elegans by looking at the early (...) stages of embryogenesis, up to several hundreds of cells (lima bean larval stage). We show how the many results that have been obtained by several groups can be interpreted in terms of values for the parameters controlling the dynamical system. Furthermore, we can extend the model to the cases of genetic mutations. More precisely the teratogenetic and lethal effects are associated with abnormal variation of the control parameters with time. (shrink)

First published in 1945. In this work the author seeks to correct the misinterpretation and incorrect labelling of Shelley's thought. While not neglecting Shelley as a poet, this book focuses on his contributions made to the general movement of political and philosophical thought of his era and by so doing his relevance to contemporary issues. This title will be of interest to students of literature.