The Polar Diagram [1] of a set of points (i.e. sites) is a partition of the plane. It is a locus approach for problems processing angles. Also, Dynamic Polar Diagram problem is a problem in which some points can be added to or removed from the point set of the Polar Diagram. Sadeghi et al. [4] introduced this problem and solved it using an algorithm which is optimal in the case that some points...

For successful generation of different cell types by asymmetric cell division, cell differentiation should be initiated only after completion of division. Here, we describe a control mechanism by which Caulobacter couples the initiation of a developmental program to the completion of cytokinesis. Genetic evidence indicates that localization of the signaling protein DivK at the flagellated pole ...

Nearly all adaptive optics images of Titan taken between December 2001 and November 2004 showed tropospheric clouds located within 30◦ of the south pole. We report here on a dissipation of Titan’s south polar clouds observed in twenty-nine Keck and Gemini images taken between December 2004 and April 2005. The near complete lack of south polar cloud activity during this time, and subsequent resu...

To examine the dependence of poleward force at a kinetochore on the number of kinetochore microtubules (kMTs), we altered the normal balance in the number of microtubules at opposing homologous kinetochores in meiosis I grasshopper spermatocytes at metaphase with a focused laser microbeam. Observations were made with light and electron microscopy. Irradiations that partially damaged one homolog...

A critical examination is made of the somewhat loose and incomplete statement that a polar diagram is the Fourier transform of an aperture distribution. By aperture distribution it is necessary to understand, in the two-dimensional case, distribution across the aperture of the component along the aperture plane of the electromagnetic field in the plane of propagation. Furthermore, the concept o...

Anterior-posterior patterning and germ cell specification in Drosophila requires the establishment, during oogenesis, of a specialized cytoplasmic region termed the pole plasm. Numerous RNAs and proteins accumulate to the pole plasm and assemble in polar granules. Translation of some of these RNAs is generally repressed and active only in pole plasm. Vasa (VAS) protein, an RNA helicase and a co...

The Mars Polar Lander (MPL) mission is the first planetary mission to w e Internet-based distributed ground operations where scientista and engineers cod labornte in daily mission operations f+om multiple geographically distributed locations via the Internet. This paper describes the operations system, the Web Interface for Telescience (WITS), which is used by the MPL mission for Internet-based...

A non-stationary model of the polar gap discharge in pulsars is reviewed and modiied. It is argued that the polar gap is braking down via a number of localized spark discharges, feeding a corresponding subpulse-associated plasma columns in the pulsar magnetosphere. It is demonstrated that each spark occupies a region of the polar cap with a characteristic dimension approximately equal to the he...

Asymmetric localization is key to the proper function of certain prokaryotic proteins important to virulence, chemotaxis, cell division, development, motility, and adhesion. Shigella IcsA is localized to the old pole of the bacterium, where it mediates assembly of an actin tail inside infected mammalian cells. IcsA (VirG) is essential to Shigella intracellular motility and virulence. We used tr...

Mitochondria of early Drosophila embryos were observed with a transmission electron microscope and a fluorescent microscope after vital staining with rhodamine 123, which accumulates only in active mitochondria. Rhodamine 123 accumulated particularly in the posterior pole region in early cleavage embryos, whereas the spatial distribution of mitochondria in an embryo was uniform throughout cleav...