It is shown that in a linearly ordered MV-algebra A , the implication is unique if and only if the identity function is the unique De Morgan automorphism on A . Modulo categorical equivalence, our uniqueness criterion recalls Ohkuma's rigidness condition for totally ordered abelian groups. We also show that, if A is an Archimedean totally ordered MV-algebra, then each non-trivial De Morgan automorphism of the underlying involutive lattice of A yields a new implication on A , which is not (...) isomorphic to the original implication. (shrink)

Over the past decade, sequence learning has gradually become a central paradigm through which to study implicit learning. In this chapter, we start by briefly summarizing the results obtained with different variants of the sequence learning paradigm. We distinguish three subparadigms in terms of whether the stimulus material is generated either by following a fixed and repeating sequence (e.g., Nissen & Bullemer, 1987), by relying on a complex set of rules from which one can produce several alternative deterministic sequences (e.g., (...) Lewicki, Hill & Bizot, 1988; Stadler, 1989), or by following the output of a probabilistic set of rules such as instantiated by noisy finite-state grammars (Cleeremans & McClelland, 1991; Jiménez, Mendéz & Cleeremans, 1996). Next, we focus on the processes involved in sequence representation and acquisition. We suggest that the sensitivity to the sequential structure observed in the probabilistic subparadigm can only be a result of the acquisition of a representation of the statistical constraints of the material, and that this sensitivity emerges through the operation of mechanisms that are well instantiated by connectionist models such as the Simple Recurrent Network (Elman, 1990; Cleeremans, 1993b). We present new simulation work meant to explore to what extent the model can also account for specific data obtained in a paradigmatic instance of deterministic, rule-based sequence learning task: Lewicki et al. (1988)'s situation. Finally, we report on the results of an experiment that compares learning on otherwise similar deterministic and probabilistic structures, and we show that learning of both types of structures is equivalent only under conditions that maximally hinder explicit acquisition. Taken together, these simulation and experimental data lend support to the claim that implicit learning in all three sequence learning subparadigms can amount to a form of statistical sequence learning. They also suggest that distinguishing among several theories of sequence representation and acquisition may require us to analize the data in great detail. Hopefully, however, some truth can be found in such details.. (shrink)

How did the new developments of the Renaissance affect the way women were understood by men and the way they understood themselves? Addressing a wide range of issues across Renaissance culture--humanism, technology, science, anatomy, literacy, theater, domesticity, colonialism, and sex--this collection of essays attempts to answer that question. In doing so, the authors discover that the female subject of the Renaissance shares a surprising amount of conceptual territory with her postmodern counterpart.

The fundamental assumption of many successful geochemical and geomicrobial technologies developed in the past 80 years is that hydrocarbons leak from subsurface accumulations vertically to the surface. Driven by buoyancy, the process involves sufficiently large volumes directly measurable or indirectly inferable from their surface expressions. Even when the additional hydrocarbons are not measurable, their presence slightly changes the environment where complex microbial communities live, and acts as an evolutionary constraint on their development. Because the ecology of this ecosystem is very (...) complicated, we have used the full-microbiome analysis of the shallow sediments samples instead of targeting only a selected number of known species and the use of machine learning for uncovering meaningful correlations in these data. We achieved this by sequencing the microbial biomass in each sample and generating its “DNA fingerprint,” and by analyzing the abundance and distribution of the microbes over the data set. Our technology uses machine learning as a fast and accurate tool for determining the detailed interactions among the various microorganisms and their environment due to the presence or absence of hydrocarbons, thus overcoming data complexity. In a proof-of-technology study, we have taken more than a thousand samples in the Neuquén Basin in Argentina over three distinct areas, namely, an oil field, a gas field, and a dry location outside the basin, and created several successful predictive models. We kept a subset of randomly selected samples outside of the training set and asked the client operator to blind them, providing the means for objectively validating the prediction performance of this methodology. Uncovering the blinded data set after estimating the prospectivity for each sample revealed that we correctly predicted most of these samples. This very encouraging result indicates that analyzing the microbial ecosystem in shallow sediment can, with the appropriate training data, be an additional derisking method in assessing hydrocarbon prospects and improve the probability of success of a drilling campaign. (shrink)

The title of this presentation may suggest that the subject is homocystinuria. It is not. Rather, the subject is how our epistemology influences our concept of disease, which in turn determines our ability to help patients.

Even a decade after the end of the 1914–1918 war, economic theory assumed that the world was tranquil and orderly. By 1939 an economic slump without parallel, allied to the re-emergence of military ambition in Europe, had brought economic theorists face to face with reality. In this classic book, first published in 1967, Professor Shackle provides a study, in exact and professional language, of the precise nature, structure, presuppositions, language and inter-relations of the theories which were formulated in these fourteen (...) years - unparalleled in the whole history of economics except perhaps by the years of the Physiocrats and Adam Smith. These theories are not prototypes on the way to something better but are of essential and permanent importance. (shrink)