PURPOSE Bacillus endophthalmitis is a highly explosive infection of the eye that commonly results in rapid inflammation and vision loss, if not loss of the eye itself, within a few days. Quorum-sensing-controlled toxins are essential to virulence during infection. Another unique characteristic of this disease is the ability of Bacillus to replicate rapidly and migrate to all parts of the eye. T...

PldB, a Putative Phospholipase D Homologue, Mediates Quorum Sensing in Dictyostelium discoideum Development by Yi Chen Adviser: Derrick Brazill, Ph.D. Quorum sensing, the ability to measure the local cell density, is required for animal cells to achieve proper cell growth, differentiation and development. However, because of the genetic intractability of mammalian cells, we study quorum sensing...

A quorum system is a collection of sets (quorums) every two of which intersect. Quorum systems have been used for many applications in the area of distributed systems, including mutual exclusion, data replication and dissemination of information Given a strategy to pick quorums, the load L(S) is the minimal access probability of the busiest element, minimizing over the strategies. The capacity ...

Many Proteobacteria use N-acyl-homoserine lactone (acyl-HSL) quorum sensing to control specific genes. Acyl-HSL synthesis requires unique enzymes that use S-adenosyl methionine as an acyl acceptor and amino acid donor. We developed and executed an enzyme-coupled high-throughput cell-free screen to discover acyl-HSL synthase inhibitors. The three strongest inhibitors were equally active against ...

Closed user group based on a Peer-to-Peer system require a membership mechanism that is fully decentralized. Several suggestions have been made in the literature. However, the proposed mechanisms have some significant drawbacks since any peer can easily bypass the proposed membership mechanism. In this paper we present a new fully decentralized and secure membership mechanism for Peer-to-Peer s...

Consistency in data storage systems requires any read operation to return the most recent written version of the content. In replicated storage systems, consistency comes at the price of delay due to large-scale write and read operations. Many applications with low latency requirements tolerate data staleness in order to provide high availability and low operation latency. Using age of informat...

Given a set of nodes S, a coterie is a set of pairwise intersecting subsets of S. Each element in a coterie is called a quorum. Mutual exclusion in a distributed system can be achieved if each request is required to get consensus from a quorum of nodes. This technique of quorum consensus is also used for replicated distributed database systems, and bicoteries and wr-coteries have been deened to...

As communication becomes more and more an integral part of our day to day lives, so our need to access information increases as well. Mobility is currently one of the most important factors to consider in our aim to achieve ubiquitous computing, and with it rises the problem of how to manipulate data while maintaining consistency and integrity. Recent years have seen tremendous interest in quor...

Bacteria are able to synchronize the population behavior in order to regulate gene expression through a cell-to-cell communication mechanism called quorum sensing. This phenomenon involves the production, detection and the response to extracellular signaling molecules named autoinducers, which directly or indirectly regulate gene expression in a cell density-dependent manner. Quorum sensing may...