1.1 Complex modular organization When grown on semi-solid surfaces, P. vortex organize its colonies by generating rotating modules (termed vortices), each consisting of many cells, which are used as building blocks for the colony as a whole [1-17] as is illustrated in Figure S1. Each vortex is composed of many cells that swarm collectively around their common center at about 10 micron/sec (see ...

Cross-coupled phenomena of multiferroic domains and domain walls are of fundamental scientific and technological interest. Using cryogenic magnetic force microscopy, we find alternating net magnetic moments at ferroelectric domain walls around vortex cores in multiferroic hexagonal ErMnO(3), which correlate with each other throughout the entire vortex network. This collective nature of domain w...

We study the general phenomenon of randomorganization using a vortex system.When a periodic shearwith a small shear amplitude dinp is applied tomany-particle (vortex) assemblies with a random distribution, the particles (vortices) gradually self-organize to avoid future collisions and transform into an organized configuration. This is detected from the time-evolution of the voltageV t ( ) (aver...

Loen, NORWAY, 7-11 May, 2001 The original version of this material will be published by the Research and Technology Organization, North Atlantic Treaty Organization (RTO/NATO) in Meeting Proceedings, MP-069 "Advanced Flow Management, Part A Vortex Flow and High Angle of Attack", in the Spring 2002. For permission to copy or republish, contact the NATO/RTO Research and Technology Agency, BP 25 7...

We present results of experiments on the dynamics of Dictyostelium discoideum in a novel setup which constrains cell motion to a plane. After aggregation, the amoebae collect into round “pancake” structures in which the cells rotate around the center of the pancake. To provide a mechanism for the self-organization of the Dictyostelium cells, we have developed a new model of the dynamics of self...

this paper is about experimental results for partial reduction of vortex at vertical pipe intakes. one of the easiest and practical ways of reducing vortex effect is to use anti-vortex plates or baffles. these plates can be used to avoid the vortex completely or partially. this paper will concentrate on the latter case. rectangular plates with different dimensions have been placed at different ...

We develop a kinetic theory for point vortices in two-dimensional hydrodynamics. Using standard projection operator techniques, we derive a Fokker-Planck equation describing the relaxation of a "test" vortex in a bath of "field" vortices at statistical equilibrium. The relaxation is due to the combined effect of a diffusion and a drift. The drift is shown to be responsible for the organization ...