Quorum systems are commonly used to maintain the consistency of replicated data in a distributed system. Much research has been devoted to developing quorum systems with good theoretical properties, such as fault tolerance and high availability. However, even given a theoretically good quorum system, it is not obvious how to efficiently deploy such a system in a real network. This paper introdu...

Replicated systems often use quorums in order to increase their performance and availability. We study the running time of quorum-based distributed systems deployed in a widely distributed setting over the Internet. We study a simple primitive that propagates information from a quorum of hosts to a either one host or to a quorum of hosts; this primitive occurs in numerous distributed systems. W...

Quorum sensing is a regulatory mechanism (operating in response to cell density) which in gram-negative bacteria usually involves the production of N-acyl homoserine lactones (HSL). Quorum sensing in Burkholderia cepacia has been associated with the regulation of expression of extracellular proteins and siderophores and also with the regulation of swarming and biofilm formation. In the present ...

background: quorum sensing (qs) is a mechanism used by bacteria to determine their physiological activities and coordinate gene expression based on cell to cell signaling. many bacterial physiological functions are under the regulation of quorum sensing such as virulence, luminescence, motility, sporulation and biofilm formation. the aim of the present study was to isolate and characterize quor...

In this presentation the hydro dynamical condition of quorum sensing in the biofilm growth is investigated using convection diffusion reaction equation and analyzed environmental condition. It is used to analyze the influence of hydrodynamics and structural heterogeneities on mass transfer in this quorum sensing mechanism. The future direction of stochastic model of quorum sensing in bacteria i...

Quorum signals are diffusible factors produced by bacteria that coordinate communal responses. For nontypeable Haemophilus influenzae (NTHi), a series of recent papers indicate that production and sensing of quorum signals are determinants of biofilm formation/maturation and persistence in vivo. In this mini-review I will summarize the current knowledge about quorum signaling/sensing by this or...

Pathogenic bacteria use quorum-sensing signal molecules to co-ordinate the expression of virulence genes. Animal-based studies have demonstrated the immunomodulatory effects of quorum-sensing signal molecules. In the present study, we have examined the impact of these molecules on normal human immune function in vitro and compared this with immune changes in patients with sepsis where quorum-se...

For many years bacteria were considered primarily as autonomous unicellular organisms with little capacity for collective behaviour. However, we now appreciate that bacterial cells are in fact, highly communicative. The generic term 'quorum sensing' has been adopted to describe the bacterial cell-to-cell communication mechanisms which co-ordinate gene expression usually, but not always, when th...

Signaling mechanisms that govern physiological and morphological responses to changes in cell density are common in bacteria. Quorum sensing, as such signal transduction processes are called, involves the production of, release of, and response to hormone-like molecules (autoinducers) that accumulate in the external environment as the cell population grows. Quorum sensing is found in a wide var...

Bacterial conversations: talking, listening and eavesdropping. An introduction 1115 I. Joint, J. Allan Downie & P. Williams Look who’s talking: communication and quorum sensing in the bacterial world 1119 P. Williams, K. Winzer, W. C. Chan & M. Cámara Cell–cell communication in the plant pathogen Agrobacterium tumefaciens 1135 C. E. White & S. C. Winans Quorum-sensing regulation in rhizobia and...