We present a new method for continuously tracking the location of the Gulf Stream using a moored array of inverted echo sounders. Time series of lateral displacements of the front, shown accurate to -+8 km, have been collected along three sections spaced 100, 150, and 200 km downstream (NE) of Cape Hatteras, North Carolina, for a period of 12 months. These records are highly coherent at all per...

Kinetochores attach chromosomes to the mitotic spindle. After binding initially to the sides of spindle microtubules, they form stable attachments to microtubule plus ends so that chromosomes can be segregated to the spindle poles during anaphase. In addition , kinetochores recruit the spindle assembly checkpoint proteins that prevent cells from entering anaphase if their chromosomes aren't att...

This article analyzes directed lattice paths, when a boundary reflecting or absorbing condition is added to the classical models. The lattice paths are characterized by two time-independent sets of rules (also called steps) which have a privileged direction of increase and are therefore essentially one-dimensional objects. Depending on the spatial coordinate, one of the two sets of rules applie...