BACKGROUND
Many microorganisms, including myxobacteria, cyanobacteria, and flexibacteria, move by gliding. Although gliding always describes a slow surface-associated translocation in the direction of the cell's long axis, it can result from two very different propulsion mechanisms: social (S) motility and adventurous (A) motility. The force for S motility is generated by retraction of type 4 pili. A motility may be associated with the extrusion of slime, but evidence has been lacking, and how force might be generated has remained an enigma. Recently, nozzle-like structures were discovered in cyanobacteria from which slime emanated at the same rate at which the bacteria moved. This strongly implicates slime extrusion as a propulsion mechanism for gliding.


RESULTS
Here we show that similar but smaller nozzle-like structures are found in Myxococcus xanthus and that they are clustered at both cell poles, where one might expect propulsive organelles. Furthermore, light and electron microscopical observations show that slime is secreted in ribbons from the ends of cells. To test whether the slime propulsion hypothesis is physically reasonable, we construct a mathematical model of the slime nozzle to see if it can generate a force sufficient to propel M. xanthus at the observed velocities. The model assumes that the hydration of slime, a cationic polyelectrolyte, is the force-generating mechanism.


CONCLUSIONS
The discovery of nozzle-like organelles in various gliding bacteria suggests their role in prokaryotic gliding. Our calculations and our observations of slime trails demonstrate that slime extrusion from such nozzles can account for most of the observed properties of A motile gliding.

How myxobacteria glide

This chapter contains sections titled: Organizing Committee, Motivations and Goals, Contributions, Proceedings

Verification, Model Checking and Abstract Interpretation

In this project you will again use Monte Carlo methods to study a physical system. The system is extremely simple and you don’t need to know any physics at all to understand it. Imagine that a large number of small solid particles are suspended in a fluid, moving around randomly due to thermal motions (“Brownian motion”). In the center of the region is a cluster of these particles, all stuck together. Whenever a new particle touches the cluster, it sticks to it. After the cluster has grown to a fairly large size, what will be its shape? Your task is to create a computer simulation to answer this question.

Diffusion Limited Aggregation

In recent years, the notion of intelligent buildings (IBs) has become increasingly popular due to their potentials for deploying design initiatives and emerging technologies towards maximized occupants’ comfort and well-being with sustainable design. However, various definitions, interpretations, and implications regarding the essence of IBs exist. Various key performance indicators of IBs have been proposed in different contexts. This study explores the notion of IBs and presents an analysis of their main constituents. Through a comparison of these constituents in different contexts, this study aims to extract the common features of IBs leading to an evolved definition which could be useful as a reference framework for design, evaluation, and development of future IBs. Findings also scrutinize the long run benefits of IBs, while demonstrating the constraints and challenges of the current international interpretations.

/pdf/what-is-an-intelligent-building-analysis-of-recent-4b0dmd6oxs.pdf

What is an intelligent building? Analysis of recent interpretations from an international perspective

ion Refinement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Pei-Hsin Ho

Automated Technology for Verification and Analysis

LaVail (Eds), Retinal Degenerative Diseases (Advances in Experimental Medicine and Biology 723) ISBN 978-1-4614-0630-3 7 * € (D) 213,95 | € (A) 219,94 | sFr 266,50 7 € 199,95 | £180.00 Special_SpacerSpecial_Spacer Mylonakis (Eds), Recent Advances on Model Hosts (Advances in Experimental Medicine and Biology 710) ISBN 978-1-4419-5637-8 7 * € (D) 149,75 | € (A) 153,94 | sFr 201,00 7 € 139,95 | £126.00 Special_SpacerSpecial_Spacer

Advances in intelligent and soft computing

Abstract The object of the presented paper is to demonstrate the possibility of equalizing the transmission properties of networks described by graphs with an equal number of nodes of the same degree but differing in diameter and average path length. A node of a graph is understood to be a specialised device performing commutation and transmission functions, while an edge is understood to be a transmission link. It was assumed that this alignment can be achieved by controlling the transmission resources assigned to specific edges of a graph through which the network nodes communicate with each other. The concept of transmission resource, counted in contractual units, is understood as, for example, the number of time slots or the bandwidth of the links used to transmit information. The authors show that with the proposed method, the equalization of the mentioned network properties is achieved with a minimal increase in the global resources used for transmission. 

/pdf/equalising-the-transmission-properties-of-graph-modelled-7y2lq31n.pdf

B. Marciniak

Papers

Advances in intelligent and soft computing

Equalising the Transmission Properties of Graph-Modelled Networks by Introducing the Control of the Resources Used to Transmit Information