Tarski apresentou sua definição de operador de consequência com a intenção de expor as concepções fundamentais da consequência lógica. Um espaço de Tarski é um par ordenado determinado por um conjunto não vazio e um operador de consequência sobre este conjunto. Esta estrutura matemática caracteriza um espaço quase topológico. Este artigo mostra uma visão algébrica dos espaços de Tarski e introduz uma lógica proposicional modal que interpreta o seu operador modal nos conjuntos fechados de algum espaço de Tarski. DOI:10.5007/1808-1711.2010v14n1p47.

Tarski presented his definition of consequence operator to explain the most important notions which any logical consequence concept must contemplate. A Tarski space is a pair constituted by a nonempty set and a consequence operator. This structure characterizes an almost topological space. This paper presents an algebraic view of the Tarski spaces and introduces a modal propositional logic which has as a model exactly the closed sets of a Tarski space. • DOI:10.5007/1808-1711.2010v14n1p47.

En este trabajo se define formamente el concepto de representacion en química utilizando homomorfismos desde estructuras algebraicas, que llamamos sistemas de tipo C, en otras estructuras especiales de símbolos muy relacionados con los que son habituales en la qímica experimental. Para la definicion de los sistemas de tipo C se ha seleccionado un conjunto minimo de relaciones y funciones, que son necesarias para expresar proposiciones significativas en química. Tambien se define un lenguaje formal de primer orden adecuado a los sistemas (...) de tipo C, que llamamos L. EI resultado principal que se demuestra es que toda representación que verifica las mismas sentencias de L que un sistema de tipo C, es necesariamente isomorfo a él. Se concluye por lo tanto que puede existir un problema linguístico subyacente en la aplicacion que de la mecaníca cuántica se hace en la química teórica.The concept of representation in chemistry bas been formallv defined by means of homomorphisms from algebraical structures, which we call type-C systems, to some special sets of symbols which can be related to the symbols ordinarily used in experimental chemistry. A minimum number of relations and functions, which would suffice to express significant propositions in chemistry, have been chosen to define type-C systems. A first order formal language L adequate to type-C systems has been defined. It has been shown that each representation that verifies the same sentences of L as a type-C system is necessarily isomorphic to it. It is concluded that a systematic study of the representation problem in chemistry is in order because a deep language problem underlies the application of quantum mechanies to chemical problems. (shrink)

En este trabajo se define formamente el concepto de representacion en química utilizando homomorfismos desde estructuras algebraicas, que llamamos sistemas de tipo C, en otras estructuras especiales de símbolos muy relacionados con los que son habituales en la qímica experimental. Para la definicion de los sistemas de tipo C se ha seleccionado un conjunto minimo de relaciones y funciones, que son necesarias para expresar proposiciones significativas en química. Tambien se define un lenguaje formal de primer orden adecuado a los sistemas (...) de tipo C, que llamamos L(C). EI resultado principal que se demuestra es que toda representación que verifica las mismas sentencias de L(C) que un sistema de tipo C, es necesariamente isomorfo a él. Se concluye por lo tanto que puede existir un problema linguístico subyacente en la aplicacion que de la mecaníca cuántica se hace en la química teórica.The concept of representation in chemistry bas been formallv defined by means of homomorphisms from algebraical structures, which we call type-C systems, to some special sets of symbols which can be related to the symbols ordinarily used in experimental chemistry. A minimum number of relations and functions, which would suffice to express significant propositions in chemistry, have been chosen to define type-C systems. A first order formal language L(C) adequate to type-C systems has been defined. It has been shown that each representation that verifies the same sentences of L(C) as a type-C system is necessarily isomorphic to it. It is concluded that a systematic study of the representation problem in chemistry is in order because a deep language problem underlies the application of quantum mechanies to chemical problems. (shrink)

First published in 1975, this is a book of general intellectual interest about the role of the university in contemporary society and that of university teachers in relation to their subjects, their students, and their wider political commitments. Alan Montefiore offers preliminary analyses of the family of concepts most often invoked in discussions of these problems, taking the central dispute to be between those who hold a 'liberal' view of the university and those who regard this notion as illusory, dishonest (...) or undesirable. Six academics, representing, discuss issues of substantive conflict in light of Montefiore's initial distinctions. The volume is of particular interest to students of political and social philosophy, and political and educational theory. It is also intended for a wider readership among those who care about the political status of the universities and recognize the importance and difficulty of the problems involved in this. (shrink)

Tarski presented his definition of consequence operator to explain the most important notions which any logical consequence concept must contemplate. A Tarski space is a pair constituted by a nonempty set and a consequence operator. This structure characterizes an almost topological space. This paper presents an algebraic view of the Tarski spaces and introduces a modal propositional logic which has as a model exactly the closed sets of a Tarski space.

This paper studies a family of monotonic extensions of first-order logic which we call modulated logics, constructed by extending classical logic through generalized quantifiers called modulated quantifiers. This approach offers a new regard to what we call flexible reasoning. A uniform treatment of modulated logics is given here, obtaining some general results in model theory. Besides reviewing the “Logic of Ultrafilters”, which formalizes inductive assertions of the kind “almost all”, two new monotonic logical systems are proposed here, the “Logic of (...) Many” and the “Logic of Plausibility”, that characterize assertions of the kind “many”, and “for a good number of”. Although the notion of simple majority (“more than half”) can be captured by means of a modulated quantifier semantically interpreted by cardinal measure on evidence sets, it is proven that this system, although sound, cannot be complete if checked against the intended model. This justifies the interest on a purely qualitative approach to this kind of quantification, what is guaranteed by interpreting the modulated quantifiers as notions of families of principal filters and reduced topologies, respectively. We prove that both systems are conservative extensions of classical logic that preserve important properties, such as soundness and completeness. Some additional perspectives connecting our approach to flexible reasoning through modulated logics to epistemology and social choice theory are also discussed. (shrink)

Originally published in 1944, this book was originally intended as a continuation of the 1943 publication Nautical Mathematics, which is also reissued in this series. In it, the principles set out in Nautical Mathematics are given practical applications, and the text is supplied with exercises to test and clarify the lessons. This book will be of value to anyone with an interest in the history of education in the forces during WWII.

Contents Acknowledgements vii Illustrations ix Preface xi Further Bibliography of A.C. Crombie xiii 1 Designed in the Mind: Western visions of Science, Nature and Humankind 1 2 The Western Experience of Scientific Objectivity 13 3 Historical Perceptions of Medieval Science 31 4 Robert Grosseteste 39 5 Roger Bacon [with J.D. North] 51 6 Infinite Power and the Laws of Nature: A Medieval Speculation 67 7 Experimental Science and the Rational Artist in Early Modern Europe 89 8 Mathematics and Platonism in (...) the Sixteenth-Century Italian Universities and in Jesuit Educational Policy 115 9 Sources of Galileo Galilei’s Early Natural Philosophy 149 10 The Jesuits and Galileo’s Ideas of Science and of Nature [with A. Carugo] 165 11 Galileo and the Art of Rhetoric [with A. Carugo] 231 12 Galileo Galilei: A Philosophical Symbol 257 13 Alexandre Koyré and Great Britain: Galileo and Mersenne 263 14 Marin Mersenne and the Origins of Language 275 15 Le Corps à la Renaissance: Theories of Perceiver and Perceived in Hearing 291 16 Expectation, Modelling and Assent in the History of Optics: i, Alhazen and the Medieval Tradition; ii, Kepler and Descartes 301 17 Contingent Expectation and Uncertain Choice: Historical Contexts of Arguments from Probabilities 357 18 P.-L. Moreau de Maupertuis, F.R.S. : Précurseur du Transformisme 407 19 The Public and Private Faces of Charles Darwin 429 20 The Language of Science 439 21 Some Historical Questions about Disease 443 22 Historians and the Scientific Revolution 451 23 The Origins of Western Science 465 Appendix to Chapter 10: 479 Sources and Dates of Galileos Writings [with A. Carugo] Pietro Redondi, Galileo eretico [with A. Carugo] Mario Biagioli, Galileo, Courtier Corrections to Science, Optics and Music in Medieval and Early Modern Thought 495 Index 497. (shrink)

Comprehending the origin of marine invertebrate larvae remains a key domain of research for evolutionary biologists, including the repeated origin of direct developmental modes in echinoids. In order to address the latter question, we surveyed existing evidence on relationships of homology between the ectoderm territories of two closely related sea urchin species in the genus Heliocidaris that differ in their developmental mode. Additionally, we explored a recently articulated idea about homology called ‘organizational homology’ (Muller 2003. In: Muller GB, Newman SA, (...) editors. Origination of organismal form: beyond the gene in developmental and evolutionary biology. Cambridge, MA: A Bradford Book, The MIT Press. p 51–69. ) in the context of this specific empirical case study. Applying the perspective of organizational homology to our experimental system of congeneric echinoids has led us to a new hypothesis concerning the ectoderm evolution in these species. The extravestibular ectoderm of the direct developer Heliocidaris erythrogramma is a novel developmental territory that arose as a fusion of the oral and aboral ectoderm territories found in indirect developing echinoids such as Heliocidaris tuberculata. This hypothesis instantiates a theoretical principle concerning the origin of developmental modules, ‘integration’, which has been neglected because the opposite theoretical principle, ‘parcellation’, is more readily observable in events such as gene duplication and divergence (Wagner 1996. Am Zool 36:36–43). J. Exp. Zool. (Mol. Dev. Evol.) 306B:18– 34, 2006. (shrink)

We present a distributed control modeling approach for an automated manufacturing system based on the dynamics of one-dimensional cellular automata. This is inspired by the fact that both cellular automata and manufacturing systems are discrete dynamical systems where local interactions given among their elements can lead to complex dynamics, despite the simple rules governing such interactions. The cellular automaton model developed in this study focuses on two states of the resources of a manufacturing system, namely, busy or idle. However, the (...) interaction among the resources such as whether they are shared at different stages of the manufacturing process determines the global dynamics of the system. A procedure is shown to obtain the local evolution rule of the automaton based on the relationships among the resources and the material flow through the manufacturing process. The resulting distributed control of the manufacturing system appears to be heterarchical, and the evolution of the cellular automaton exhibits a Class II behavior for some given disordered initial conditions. (shrink)

The origin of marine invertebrate larvae has been an area of controversy in developmental evolution for over a century. Here, we address the question of whether a pelagic “larval” or benthic “adult” morphology originated first in metazoan lineages by testing the hypothesis that particular gene co-option patterns will be associated with the origin of feeding, indirect developing larval forms. Empirical evidence bearing on this hypothesis is derivable from gene expression studies of the sea urchin larval gut of two closely related (...) but differently developing congenerics, Heliocidaris tuberculata (feeding indirect-developing larva) and H. erythrogramma (nonfeeding direct developer), given two subsidiary hypotheses. (1) If larval gut gene expression in H. tuberculata was co-opted from an ancestral adult expression pattern, then the gut expression pattern will remain in adult H. erythrogramma despite its direct development. (2) Genes expressed in the larval gut of H. tuberculata will not have a coordinated expression pattern in H. erythrogramma larvae due to loss of a functional gut. Five structural genes expressed in the invaginating archenteron of H. tuberculata during gastrulation exhibit substantially different expression patterns in H. erythrogramma with only one remaining endoderm specific. Expression of these genes in the adult of H. erythrogramma and larval gut of H. tuberculata, but not in H. erythrogramma larval endoderm, supports the hypothesis that they first played roles in the formation of adult structures and were subsequently recruited into larval ontogeny during the origin and evolution of feeding planktotrophic deuterostome larvae. (shrink)

A central reason that undergirds the significance of evo-devo is the claim that development was left out of the Modern synthesis. This claim turns out to be quite complicated, both in terms of whether development was genuinely excluded and how to understand the different kinds of embryological research that might have contributed. The present paper reevaluates this central claim by focusing on the practice of model organism choice. Through a survey of examples utilized in the literature of the Modern synthesis, (...) I identify a previously overlooked feature: exclusion of research on marine invertebrates. Understanding the import of this pattern requires interpreting it in terms of two epistemic values operating in biological research: theoretical generality and explanatory completeness. In tandem, these values clarify and enhance the significance of this exclusion. The absence of marine invertebrates implied both a lack of generality in the resulting theory and a lack of completeness with respect to particular evolutionary problems, such as evolvability and the origin of novelty. These problems were salient to embryological researchers aware of the variation and diversity of larval forms in marine invertebrates. In closing, I apply this analysis to model organism choice in evo-devo and discuss its relevance for an extended evolutionary synthesis. (shrink)

This paper proposes a conceptual framework for evaluating how social networking platforms fare as epistemic environments for human users. I begin by proposing a situated concept of epistemic agency as fundamental for evaluating epistemic environments. Next, I show that algorithmic personalisation of information makes social networking platforms problematic for users’ epistemic agency because these platforms do not allow users to adapt their behaviour sufficiently. Using the tracing principle inspired by the ethics of self-driving cars, I operationalise it here and identify (...) three requirements that automated epistemic environments need to fulfil: (a) the users need to be afforded a range of skilled actions; (b) users need to be sensitive to the possibility to use their skills; (c) the habits built when adapting to the platform should not undermine the user’s pre-existing skills. I then argue that these requirements are almost impossible to fulfil all at the same time on current SN platforms; yet nevertheless, we need to pay attention to these whenever we evaluate an epistemic environment with automatic features. Finally, as an illustration, I show how Twitter, a popular social networking platform, will fare regarding these requirements. (shrink)

En me posant le probleme de la méthode, je constate une diversité de solutions, et énetudiant cette diversité, je suis conduit à examiner, entre autres, la doctrine chrétienne.Mais pour comprendre cette doctrine, il faut que nous commencions par la priere, c’est-à-dire par la purification. Car c’est ainsi qu’en fait le christianisme commence toute action. Et alors, nous pouvons voir que la méthode cherchée est la croyance, mais sous des formes différentes : instinct, sensibilité, expérience, raison, pensée, esprit.Il у a donc (...) plusieurs méthodes, mais en toutes, il у a en une seule ; il у a une méthode, mais sous des formes différentes. (shrink)

This article reviews three recent books that enhance our understanding of the work of French feminist Luce Irigaray: Marine Lover of Friedrich Nietzsche and The Irigaray Reader, and Philosophy in the Feminine, a commentary on Irigaray's work by Margaret Whitford. The author emphasizes a dynamic reading of Irigaray's philosophy and integrates theoretical concepts with poetic/utopian passages from the works.

A number of studies have shown that phonetic peculiarities, especially at the coarticulation level, exist in the disfluent as well as in the perceptively fluent speech of people who stutter (PWS). However, results from fluent speech are disparate and not easily interpretable. Are the coarticulatory features a manifestation of the disorder, or rather a compensation for the disorder itself? Our purpose is to investigate the coarticulatory behavior in the fluent speech of PWS in the attempt to answer the question on (...) its symptomatic or adaptive nature. In order to achieve this, we have studied the speech of 21 adult PWS (10 French and 11 Italian) compared to that of 20 fluent adults (10 French and 10 Italian). The participants had to repeat simple CV syllables in short carrier sentences, where C = /b, d, g/ and V = /a, i, u/. Crucially, this repetition task was performed under a condition with normal auditory feedback (NAF) for both the groups, and under a fluency-enhancing condition (only for PWS) due to an altered auditory feedback (AAF). The degree of coarticulation was measured by means of the Locus Equations (LE). Under NAF conditions, the coarticulation degree observed in fluent PWS speech is lower than that of the PWNS, and, more importantly, in AAF condition, PWS coarticulation appears even weaker than in the NAF condition. The latter result allows to interpret the low degree of coarticulation found in fluent speech of PWS under NAF condition as a compensation for the disorder, based on the fact that coarticulation is weaker in fluency-enhancing conditions. Since a lower degree of coarticulation is associated to a greater separation between the places of articulation of the consonant and the vowel, these results are compatible with the hypothesis that larger articulatory movements could be responsible for the stabilization of the PWS speech motor system, increasing the kinesthetic feedback from the effector system. This interpretation shares with a number of relatively recent proposal the idea that stuttering derives from an impaired feedforward (open-loop) control system, which makes PWS rely more heavily on a feedback-based (closed loop) motor control strategy. (shrink)

Lejos de ser lo político una cuestión secundaria o extraña a la filosofía epicúrea, se arguye de este ser un componente esencial de su pensamiento que se presenta en el trato de la amistad como rasgo característico e ineludible para el constructo social decara a los conflictos internos y externos de la Grecia del siglo IV a.C. Desde esta óptica, un interés por precisar el alcance ético-político de la φιλíα (filopolitismo) tan referido en la antigüedad, pero desde un filósofo al (...) que se le endilga la defensa de apoliticidad (O’Keefe,2010; Christensen, 2020), el actual estudio explora argumentos que hacen de ese término un fundamento práctico que ofrece las mejores condiciones para una vida social en tanto puede ofrendar patrones de conducta en lo que respecta a vínculos comunitarios. Para ello se recurre al análisis de textos que se conservan de Epicuro los cuales tienen un tratamiento de la amistad como la Carta a Meneceo (Ad Menoeceum), las Máximas Capitales (Ratæ Sententiae) y las Sentencias Vaticanas (Gnomologio Vaticano), pues se trata de un estudio documental el cual tiene por fin la revisión y análisis de fuentes bibliográficas. (shrink)

Published in France in 1980, _Marine Lover_ is the first in a trilogy in which Luce Irigaray links the interrogation of the feminine in post-Hegelian philosophy with a pre-Socratic investigation of the elements. Irigaray undertakes to interrogate Nietzche, the grandfather of poststructuralist philosophy, from the point of view of water. According to Irigaray, water is the element Nietzsche fears most. She uses this element in her narrative because for her there is a complex relationship between the feminine and the fluid. (...) Irigaray's method is to engage in an amorous dialogue with the male philosopher. In this dialogue, she ruptures conventional discourse and writes in a lyrical style that defies distinction between theory, fiction, and philosophy. (shrink)

Resumen: Este artículo estudia el poder de la visualidad en la política. Entre aquello que está permitido ver y aquello que está prohibido mostrar, el régimen escópico se define por la intervención del poder institucional respecto de la mirada del espectador. Este estudio se desarrolla entre la tradición filosófica y otras aportaciones multidisciplinares (estudios visuales, comunicación social, estética, historia del arte, teoría del arte) que evidencian a) el control político en los regímenes escópicos de la mirada del espectador; b) la (...) consolidación de una cultura visual que condiciona el modo de vida de los individuos y las sociedades; c) el dominio del espacio social por medio de la regulación del espacio visual; y d) la manipulación de los afectos por medio de la experiencia visual. En este estudio destacamos la apertura de la consciencia crítica en la modernidad a la estetización de la política. Abstract: This article studies the power of visual aesthetics in politics. Between what is allowed to see and what is forbidden to show, the scopic regime is defined by the intervention of institutional power on the viewer's gaze. This study is developed between the philosophical tradition and other multidisciplinary contributions (visual studies, social communication, aesthetics, art history, art theory) that show a) political control in the scopic regimes of the viewer's gaze; b) the consolidation of a visual culture that conditions the way of life of individuals and societies; c) the domain of social space through the regulation of visual space; and d) the manipulation of affects through visual experience. In this study we highlight the opening of critical consciousness in modernity to the aestheticization of politics. (shrink)

Este artículo estudia el poder de la visualidad en la política. Entre aquello que está permitido ver y aquello que está prohibido mostrar, el régimen escópico se define por la intervención del poder institucional respecto de la mirada del espectador. Este estudio se desarrolla entre la tradición filosófica y otras aportaciones multidisciplinares que evidencian a) el control político en los regímenes escópicos de la mirada del espectador; b) la consolidación de una cultura visual que condiciona el modo de vida de (...) los individuos y las sociedades; c) el dominio del espacio social por medio de la regulación del espacio visual; y d) la manipulación de los afectos por medio de la experiencia visual. En este estudio destacamos la apertura de la consciencia crítica en la modernidad a la estetización de la política. (shrink)

The preparation of layers of amorphous Se by plasma-enhanced CVD using the hydride H2Se as precursor gas is described. Information concerning the structure of the films was obtained from Raman spectroscopy. The spectra of amorphous Se indicated that the dominant molecular structure is the eight-membered ring and/or a chain with Se8 molecular fragments. This material exhibited reversible photodarkening when illuminated at 77 K. In order to explain this phenomenon, we propose a mechanism which takes into account the role of the (...) lone-pair electron orbitals of Se in their contribution to structural ordering. Illumination can cause a distortion in the normal bonding direction between nearest-neighbour Se atoms and induce in this way intrinsic defect states located at the band edges. In the photo-darkened state, optical transition will occur between these defect states. (shrink)

Successful prototype marine chronometers, developed by Harrison and others in the eighteenth century, stimulated a sector of the British watchmaking industry to supply Admiralty and commercial demand for this instrument. Chronometers, like other British-made timepieces, were constructed by an elaborate pre-industrial method of production. The instrument's static technology and extreme durability meant replacement demand was minimal, and new demand was low relative to existing stock and the industry's capacity. The First World War created a final surge of demand that left (...) supplies far in excess of peacetime needs; and a new technology—radio transmissions of time signals—offered an alternative method of determining Greenwich time, and thus longitude, at sea. (shrink)

Résumé Domaine de réflexion toujours sensible aujourd’hui, l’embryologie donne déjà lieu dans l’Antiquité à de nombreux débats, sous-tendus par deux enjeux principaux. Le premier vise à déterminer comment l’embryon se forme et se développe. Le second est celui de l’acquisition de la vie : le fœtus n’est-il qu’une partie du corps de la mère ou doit-on le considérer comme un être autonome? À partir de quel moment est-il vivant? Or, l’analogie entre le fœtus et la plante se trouve au cœur (...) des discussions qui opposent les différentes écoles philosophiques et médicales sur ces questions, et il s’agira de souligner les différentes fonctions et les ambiguïtés de l’image. Utilisée comme l’instrument d’une description, l’analogie entre le fœtus et la plante donne lieu à des conclusions qui divergent radicalement selon les auteurs quant à la question de l’autonomie et de la vie du fœtus. L’analogie savante entre le fœtus et la plante a également permis de mettre au point une trame narrative que l’on retrouve dans les Métamorphoses d’Ovide. (shrink)

La critique féministe a dénoncé très tôt le « bonheur parfait » que la techno-science est censée apporter à nos sociétés occidentales. Mais c'est la tendance écoféministe qui a poussé le plus à fond cette critique. Nous voulons mettre en évidence les principaux enjeux identifiés par ce courant, ainsi que les types de praxis qu'il veut mettre en oeuvre pour nous libérer de l'idéologie du « progrès » et nous permettre d'accéder à une société plus humaine.The feminist critique very early (...) on denounced the "bonheur parfait" that techno-science is expected to yield in our Western societies. This line of criticism was insisted upon by ecofeminists. We would like to underscore the main issues identified by eco-feminists, together with the type of praxis it implies in order to liberate us from a progress-based ideology and to allow us accès to a more human society. (shrink)

Sommes-nous tous malades? La médecine, ses approches de l'humain, son vocabulaire ont pénétré dans notre univers quotidien. Une telle médicalisation de notre existence n'est pas sans effet. Les problèmes du corps et de l'âme se voient systématiquement redéfinis en pathologies et les différentes phases de la vie accompagnées de l'aide technique médicale. Celle-ci esquisse la figure d'un homme amélioré par les biotechnologies, débarrassé des aléas des passions, maîtrisant ses colères et ses pulsions: un homme sans fièvre. Ainsi paradoxalement, à mesure (...) que la médecine identifie toujours plus de maladies, les hommes rèvent de parfaite guérison et en font à la fois une exigence personnelle et un idéal social. Guérir la société de ses blessures, nous défaire de notre vulnérabilité; telle est la manière dont est interprétée trop rapidement l'idée d'une société du soin proposée par de nouvelles philosophies. Pourtant, soigner n'est pas un geste anodin, guérir ne se fait pas sans souffrance et généraliser le modèle médical, c'est aussi prendre le risque de banaliser sa violence spécifique. (shrink)

Dans un texte bref et essentiel prononcé et publié en 1992, Paul Ricœur interrogeait l’expérience de la souffrance au cœur de l’existence humaine. Il en dépliait les horizons dans le rapport à soi et à l’autre, depuis la douleur corporelle jusqu’à la souffrance morale. Ce volume se propose de donner aujourd’hui à relire ce texte clé tant pour sa compréhension que pour une réflexion sur l’anthropologie philosophique et l’éthique du soin. Les contributions qui le suivent, chacune à leur manière, rebondissent (...) sur les éléments d’analyse aujourd’hui particulièrement stimulants qui sont les siens, tout en les mettant en perspective avec certains enjeux très concrets du soin dans nos vies. (shrink)

Rendell and Whitehead argue persuasively that individual foraging specializations, if socially learned, are examples of cetacean culture. However, they discount ecological variation experienced by individuals within a population as a factor in such behavior. I suggest that ecological variation may play an important role in individual foraging specializations and describe several ecological parameters that may help us understand the high frequency of this interesting behavior in the marine habitat.

The influence of sediment oxygen heterogeneity, due to bioturbation, on diffusive oxygen flux was investigated. Laboratory experiments were carried out with 3 macrobenthic species presenting different bioturbation behaviour patterns: the polychaetes Nereis diversicolor and Nereis virens, both constructing ventilated galleries in the sediment column, and the gastropod Cyclope neritea, a burrowing species which does not build any structure. Oxygen two-dimensional distribution in sediments was quantified by means of the optical planar optode technique. Diffusive oxygen fluxes and a variability index were (...) calculated on the captured oxygen images. All species increased sediment oxygen heterogeneity compared to the controls without animals. This was particularly noticeable with the polychaetes because of the construction of more or less complex burrows. Integrated diffusive oxygen flux increased with oxygen heterogeneity due to the production of interface available for solute exchanges between overlying water and sediments. This work shows that sediment heterogeneity is an important feature of the control of oxygen exchanges at the sediment–water interface. (shrink)

By the time George Wilton Field concluded his work at the marine laboratory his initial scientific concerns had forced him directly into local politics. He pleaded with little success with the community of South Kingstown, and with no success with the town of Narragansett, to create and maintain a permanent breach:Is it not possible for the acute business sense and the broad philanthropy of the community to sweep aside petty, local, and personal jealousies which are now blocking practical progress for (...) the establishment of a permanent breach at Point Judith Pond? It is truly criminal neglect which permits fifteen hundred acres of valuable water-farming area to lie practically idle and rapidly deteriorate with each passing year.... In the opinion of the writer the Point Judith Pond and those of similar type could be made the seat of oyster, clam, crab, herring, white perch, and striped bass fisheries.30In the summer of 1899 Field was invited to teach a summer course on echinoderms at the MBL in Woods Hole, and to conduct summer research in a laboratory of the U.S. Fish Commission, also located at Woods Hole. When the summer was over, he remained there. Whether he had intentions of returning to resume his position in Rhode Island is unclear. At this point all correspondence with the Agricultural Experiment Station ceases, and Field's last report is a brief statement in the annual report of the experiment station for 1900 wherein he laments the variety of experiments he has not been able to carry to conclusion, such as a study of the artificial fertilization of water analogous to the method of chemically fertilizing the land for crops.The correspondence reveals that the enthusiasm Field brought to Point Judith Pond in 1896 was gradually sapped by his own fragile health, by three years' exposure to the local politics surrounding the southern Rhode Island fishing industry, and by a college administration determined to remove the stench of his invertebrates. He sought a refuge in the sheltered world of pure research at the U.S. Fish Commission Laboratory, where he set out to investigate the “Origin of Sex” using, as his animal models, squid and toadfish.On November 14, 1899, the Board of Managers of the college ordered the director of the experiment station to dispose of the marine laboratory at Point Judith Pond.31 How long the laboratory at Buttonwood Point survived in the institutional memory of the University of Rhode Island is open to question. The current Graduate School of Oceanography, in the event, traces its history back to 1937, not 1896.Nevertheless, Field and his one-room marine station established a precedent of land-grant marine research that other state colleges would follow, including Rhode Island itself, which reestablished its marine station, this time permanently, at South Ferry in 1937. In his brief research career in Rhode Island, George Wilton Field had discovered the same coastal attributes that would lead later to the creation of one of the world's major marine research centers at the University of Rhode Island's Graduate School of Oceanography.And, in a measure of triumph for his work, little more than a year after Field left for Woods Hole and his laboratory was dismantled, the town of South Kingstown voted the funds necessary to begin the construction of a permanent breachway.32 Whether Field's scientific reasoning and the conclusions of his marine research played any part in finally deciding the thirty-year-old debate in the affirmative will probably never be known. What is evident is that Field had no patience for those who could not see the results of his research as clearly as he could himself. (shrink)

A new model for early diagenetic processes has been developed through a new formula explicitly accounting for microbial population dynamics. Following a mechanistic approach based on enzymatic reactions, a new model has been proposed for oxic mineralisation and denitrification. It incorporates the dynamics of bacterial metabolism. We find a general formula for inhibition processes of which some other mathematical expressions are particular cases. Moreover a fast numerical algorithm has been developed. It allows us to perform simulations of different diagenetic models (...) in non-steady states. We use this algorithm to compare our model to a classical one (Soetaert et al., 1996). Dynamical evolutions of a perturbation of particulate organic carbon (POC) input are studied for both models. (shrink)

The collective monograph "Ontology of Stative Situations - Linguistic Modeling. A Contrastive Bulgarian-Russian Study" includes research carried out within the project of the same name "Ontology of stative situations – linguistic modeling. A contrastive Bulgarian-Russian study", supported by the "Scientific Research" Fund of the Ministry of Education and Science in Bulgaria (№ КП-06-РУСИЯ / 23) and from the Russian Fund for Fundamental Research (No. 20-512-18005).

De Interpretatione is among Aristotle's most influential and widely read writings; C. W. A. Whitaker presents the first systematic study of this work, and offers a radical new view of its aims, its structure, and its place in Aristotle's system. He shows that De Interpretatione is not a disjointed essay on ill-connected subjects, as traditionally thought, but a highly organized and systematic treatise on logic, argument, and dialectic.