Prehistoric Timber Circles

Plant Cytokinesis: Circles within Circles

The current model of the plant cytokinetic apparatus, describing it as being composed of treadmilling microtubules, is challenged by a new study showing that these microtubules display dynamic instability.

Quaternionic Product of Circles and Cycles and Octonionic Product for Pairs of Circles

This paper concerns with a product of circles induced by the quaternionic product considered in a projective manner. Several properties of this composition law are derived and on this way we arrive at some special numbers as roots or powers of unit. We extend this product to cycles as oriented circles and to pairs of circles by using the algebra of octonions. Three applications of the given pro...

Timber Cycles *

We construct an intertemporal model of rent-maximizing behaviour on the part of a timber harvester under potentially multi-dimensional risk as well as geographical heterogeneity. Subsequently, we use recursive methods (in particular, the method of dynamic programming) to characterize the optimal policy function, the rent-maximizing timber-harvesting profile. One noteworthy feature of our applic...

Late Prehistoric Southwest

examining the role of glaze \vare pottery in the social lives of the late precontact and early contact Pueblos. By tracing the circulation of spe­ cialized knowledge, raw materials, and the glaze-painted pots themselves, through interactive networks ofvarying sizes and scales, these researchers reveal how glaze ware production, distribution, and use articulated with a variety of dynamic histori...

A Prehistoric Revolution