The bacterium Myxococcus xanthus glides over surfaces using two different locomotive mechanisms, called S (social) and A (adventurous) motility that enable cells to move both as groups and as individuals. Neither mechanism involves flagella. The functions of these two motors are coordinated by the activity of a small Ras-like protein, encoded by the mglA gene. The results of previous studies of...

A Monte Carlo experiment is used to examine the size and power properties of alternative Bayesian tests for unit roots. Four different prior distributions for the root that is potentially unity – a uniform prior and priors attributable to Jeffreys, Lubrano, and Berger and Yang – are used in conjunction with two testing procedures: a credible interval test and a Bayes factor test. Two extensions...

Several major record labels are adopting a new family of copy-prevention techniques intended to limit “casual” copying by compact disc owners using their personal computers. These employ deliberate data errors introduced into discs during manufacturing to cause incompatibility with PCs without affecting ordinary CD players. We examine three such recordings: A Tribute to Jim Reeves by Charley Pr...

The speed of CPUs is accelerating rapidly, outstripping that of peripheral storage devices and making it increasingly di cult to keep CPUs busy. Multilevel memory hierarchies, scaled to simulate single-level memories, are increasing in importance. In this paper we introduce the Memory Hierarchy Game, a multi-level pebble game simulating data movement in memory hierarchies for straight-line comp...

Research partially supported by EEC under the Esprit Project 6398 VENUS. Partial support given by ONR Contract N00014-91-J-4052, ARPA Order 8225. These two classes are however incomparable (see for example [Kan90]). We consider the broad class of strati ed Datalog queries (which includes both linear and non-linear queries) and propose an extended closure operator that expresses such queries whe...

FoF1-ATP synthases are membrane-embedded protein machines that catalyze the synthesis of adenosine triphosphate. Using photoactivation-based localization microscopy (PALM) in TIR-illumination as well as structured illumination microscopy (SIM), we explore the spatial distribution and track single FoF1-ATP synthases in living E. coli cells under physiological conditions at different temperatures...