Quorum sensing Quorum sensing is a system of stimulus and response correlated to population density. Many species of bacteria use quorum sensing to coordinate gene expression according to the density of their local population. In similar fashion, some social insects use quorum sensing to determine where to nest. In addition to its function in biological systems, quorum sensing has several useful applications for computing and robotics. Quorum sensing can function as a decision-making process in any decentralized system, as long as individual components have: (a) a means of assessing the number of other components they interact with and (b) a standard response once a threshold number of components is detected. Bacteria[edit] Some of the best-known examples of quorum sensing come from studies of bacteria. Mechanism[edit] Model of quorum sensing. Examples[edit] Aliivibrio fischeri[edit] Escherichia coli[edit] Salmonella enterica[edit] Salmonella encodes a LuxR homolog, SdiA, but does not encode an AHL synthase.
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Journal home : Nature Raphael Lis, Charles C. Karrasch, Michael G. Poulos, Balvir Kunar, David Redmond, Jose G. Barcia Duran, Chaitanya R. Badwe, William Schachterle, Michael Ginsberg, Jenny Xiang, Arash Rafii Tabrizi, Koji Shido, Zev Rosenwaks, Olivier Elemento, Nancy A. Speck, Jason M. Tech News | Innovation News | Money News Quantum Levitation Syndrome from Pixar's The Incredibles levitates things on zero-point energy. We study methods [1,2] for the manipulation of the force of the quantum vacuum known as the Casimir force. It is possible to turn the Casimir force from attraction to repulsion and to use it for levitating mirrors on, literally, nothing. This research may be interesting for applications in nanotechnology, because the Casimir force is the ultimate source of friction for micro- and nano-machines. In the following we explain the science behind Quantum Levitation [1]. Gecko feet [3]. A gecko can hang on a glass surface using only one toe. Field lines of the van der Waals force between two atoms or molecules. What is the van der Waals force? The physics behind the van der Waals force: neutral atoms or molecules electrically polarize each other. However, the dipole of one molecule does only form in the presence of another particle. Imagine that you replace the molecules by larger bodies, say glass or metal plates. U.
Physical Review B