A nonlinear two-variable reaction-diffusion model of bone mineral metabolism, built from an overall self-oscillatory compartmental model of calcium metabolism in vivo, has been studied for its ability to generate spatial and spatio-temporal self-organizations in a two-dimensional space. Analytical and numerical results confirm the theoretical properties previously described for this kind of model. In particular, it is shown that, for a given set of reactional parameter values and certain values of the ratio of the two diffusion coefficients, there exists a set (...) of unstable wavenumbers leading spontaneously to the development, from the homogeneous steady state, of either different types of stationary spatial patterns (hexagonal, striped and re-entrant hexagonal patterns) or more or less complex spatio-temporal expressions. We discuss the relevance of analogies established between some spatial or spatio-temporal structures predicted by the model and some peculiar features of the primary bone trabecular architecture which appear during embryonic ossification. (shrink)

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Die religionstheologische Hermeneutik der Gegenwartskultur ist zu einem grundlegenden Forschungsfeld einer sich als Theorie der Religionspraxis verstehenden Praktischen Theologie geworden. Das Asthetische ist als eine zentrale Dimension des Kulturellen deshalb neu in den Mittelpunkt der Aufmerksamkeit geruckt. Die Erforschung der Zusammenhange von <I>Asthetik und Religion steht jedoch erst am Anfang. Mit dem Band kann ein teilweiser Uberblick uber den Stand der Diskussion zum Thema <I>Identitat und Differenz von asthetischer und religioser Erfahrung gegeben werden. Er bietet eine Zusammenschau unterschiedlicher Zugange zu (...) den Phanomenen bzw. differenter Theoriestrategien und weist Perspektiven fur den interdisziplinaren Diskurs auf, in denen die theoretischen Voraussetzungen und methodischen Massgaben fur die Verhaltnisbestimmung von religioser und asthetischer Erfahrung zu klaren sind.". (shrink)