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{The paper studies the implications of bounding the complexity of the strategies players may select, on the set of equilibrium payoffs in repeated games. The complexity of a strategy is measured by the size of the minimal automaton that can implement it. A finite automaton has a finite number of states and an initial state. It prescribes the action to be taken as a function of the current state and a transition function changing the state of the automaton as a function of its current state and the present actions of the other players. The size of an automaton is its number of states. The main results imply in particular that in two person repeated games, the set of equilibrium payoffs of a sequence of such games. G(n)

Self-diffusion of all components in two different microemulsions has been studied by the Fourier-transform pulsed-gradient spin echo 1H NMR technique. The anal. of hydrodynamic and direct droplet-droplet interactions in microemulsions allows the simultaneous application of the Stokes-Einstein equation for surfactant and oil. The result of this anal. is a simple relation connecting self-diffusion coeffs. of components and the size of droplets. It is shown that because of partial solubilization of water in oil the droplet radius can be significantly different from the expected radius. [on SciFinder(R)]

Self-assembled chromophoric multilayers having large second-order optical nonlinearities can be combined with linear guiding materials such as polymethylmethacrylate to produce two-component frequency doublingwaveguides. This approach introduces considerable flexibility in optimizing the trade-off between the overlap of waveguide mode profiles and linear absorption. Extremely low waveguide propagation losses can be achieved because electric field poling and the accompanying poling-induced optical scattering are obviated.

A mixture of two different types of grain can undergo spontaneous stratification simply by being poured. This surprising behaviour may be significant in fields from pharmaceuticals to geology.

Our objective was to determine whether colorectal cancer tissue synthesizes and secretes biologically active gastrins resulting in a rise of gastrin levels in patients with adenocarcinoma of the colon. Blood samples for gastrin determination were taken from the artery feeding, and from the vein draining colon tumors, from a vein draining an uninvolved colon segment and from a peripheral vein. Tissue gastrin levels were measured in tumor tissues and normal mucosa taken by colonoscopic biopsy from colon cancer patients and healthy controls. The setting was a university hospital research laboratory. We had seventeen patients with colorectal cancer and 23 controls. No significant difference was found in peripheral venous blood gastrin levels between the cancer and the control groups. Serum gastrin concentration was not significantly different in the arterial blood which supplied the tumor area, the venous blood draining the tumor, the "uninvolved" mucosa or the control normal epithelium. Cancer tissue gastrin levels were lower than those measured in biopsies of uninvolved mucosa from cancer patients and normal controls. The present results show no rise of gastrin blood levels in patients with colon cancer, nor any evidence of gastrin-increased synthesis by the tumors.

This ariticle concerns the interactive modal propositional calculus, using the multi-agent epistemic logic S5. With regard to the space of maximally consistent sets of formulas, the relations between three aspects of common knowledge are investigated: 1) whether common knowledge defined semantically is determined by the set of formulas held in common knowledge, 2) the partial order by inclusion of the sets of formulas that can be held in common knowledge, and 3) the cardinality of a generating set of formulas for those held in common knowledge. Additionally, assuming at least two agents, it is shown that the number of connected components of holding only the tautologies in common knowledge has the cardinality of the continuum.

La revue belge Empreintes consacra en 1950 un numéro spécial à Jean Cocteau. On demanda à Genet de participer à l'hommage rendu au poète. Le texte qu’il écrivit (Jean Cocteau) n'a pas été repris dans les Euvres Complètes comme n'a pas été reprise la Lettre à Léonor Fini, publiée la mème année chez Jacques Loyau. Ces deux textes sont les deux premiers écrits purement analytiques de Genet. Il les compose en marge de La Mort. Et l'on retrouve, entre leurs lignes, les thèmes du grand ouvrage abandonné. Comment métamorphoser la théfitralité des thèmes oniriques en une forme classique, universelle ? Comment ériger une nouvelle morale dont les valeurs soient esthétiques ? La morale de 1’artiste obéit, elle aussi, au Beau. C'est par le pinceau ou le style qu’il parvient à la sainteté. D’autre part, en méme temps que Genet écrit sur Cocteau et Fini, Sartre écrit sur Genet. Entre Sartre et Genet, il y a eu (pendant quelques années du moins) un dialogue véritable, un dialogue d’auvres. Et le Saint Genet va faire écho aux idées dé- veloppées dans ces deux petits textes : la sainteté de l'artiste ; sa nécessaire métamorphose.