Developing A Mathematical Model For Locating Facilities And Vehicles To Minimize Response Time

Traditional mathematical models for locating/allocating vehicles and facilities are reviewed and extended to illustrate how to formulate and solve a problem of minimized response time, given resource constraints.  Results indicate that the average response time can be significantly improved through strategically allocating vehicles throughout the service area.  Furthermore, the modified model was shown to outperform the traditional model as the number of vehicles allocated to a fixed number of facilities increase.  Implications are identified for applications such public transit systems, wholesale and distribution operations

Alternative Mechanisms for Tn5 Transposition

Bacterial transposons are known to move to new genomic sites using either a replicative or a conservative mechanism. The behavior of transposon Tn5 is anomalous. In vitro studies indicate that it uses a conservative mechanism while in vivo results point to a replicative mechanism. To explain this anomaly, a model is presented in which the two mechanisms are not independent—as widely believed—but could represent alternate outcomes of a common transpositional pathway