4 research outputs found
Can the strong get stronger? A laboratory investigation of natural selection for antimicrobial resistance
The students, Sarah Grace Keaveany and Elizabeth Ramsey, completed original research with to investigate 1) standing variation among common bacterial species (Escherichia coli and Stapholococcus epidermidis) in the amount of resistance to triclosan, a common anti-microbial used in hand washes; and 2) the capacity for these bacteria to develop increased resistance to triclosan through selection. The students have developed lab modules based on this research. One module includes a wet lab, where students will culture their own bacteria. The other module allows students to obtain data from photographs of bacterial plates in lieu of a wet lab component
Effect of the current-wave angle on the local scour around circular piles
This paper studies the effect of the wave front-current angle on the scour around a circular pile. An experimental study was carried out in the Coastal, Ocean and Sediment Transport (COAST) laboratory at the University of Plymouth (UK) using a single monopile of 0.125 m in diameter and an 8 m long by 1.5 m wide by 0.2 m high sand pit. The results obtained during the test campaign show the influence of the angle between waves and currents on both the maximum scour depth and the time scale of the process. Wave fronts partially aligned with current (65°) produce deeper scour holes than perpendicular forcing conditions (90°). Wave fronts partially against the current (115°) produce less scour than any of the two previous scenarios. The addition of waves reduced the maximum scour depth, compared with the current-only case. The development of the scour hole was found to be more rapid when waves are added to the current, with 50% of the final scour achieved in half the time. The results show that wave direction relative to the current is an important component in scour prediction.The authors would like to thank the contribution of Dr. Kieran Monk, Mr. Gregory Nash, Mr. Peter Arber, Mr. Alastair Reynolds, and Mr. Andrew Oxenham during the test setup and the whole experimental campaign. The research was supported by Intelligent Community Energy (ICE) project, INTERREG V FCE, European Commission (Contract No. 5025).Peer ReviewedPostprint (author's final draft
A Large Community Outbreak of Legionnaires' Disease Associated With a Cooling Tower in New York City, 2015
Objectives: Infections caused by Legionella are the leading cause of waterborne disease outbreaks in the United States. We investigated a large outbreak of Legionnaires' disease in New York City in summer 2015 to characterize patients, risk factors for mortality, and environmental exposures.
Methods: We defined cases as patients with pneumonia and laboratory evidence of Legionella infection from July 2 through August 3, 2015, and with a history of residing in or visiting 1 of several South Bronx neighborhoods of New York City. We describe the epidemiologic, environmental, and laboratory investigation that identified the source of the outbreak.
Results: We identified 138 patients with outbreak-related Legionnaires' disease, 16 of whom died. The median age of patients was 55. A total of 107 patients had a chronic health condition, including 43 with diabetes, 40 with alcoholism, and 24 with HIV infection. We tested 55 cooling towers for Legionella, and 2 had a strain indistinguishable by pulsed-field gel electrophoresis from 26 patient isolates. Whole-genome sequencing and epidemiologic evidence implicated 1 cooling tower as the source of the outbreak.
Conclusions: A large outbreak of Legionnaires' disease caused by a cooling tower occurred in a medically vulnerable community. The outbreak prompted enactment of a new city law on the operation and maintenance of cooling towers. Ongoing surveillance and evaluation of cooling tower process controls will determine if the new law reduces the incidence of Legionnaires' disease in New York City