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Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Swarthmore College

1998

Articles 1 - 3 of 3

Full-Text Articles in Life Sciences

Bacterial Stress Responses To 1-Megahertz Pulsed Ultrasound In The Presence Of Microbubbles, Amy Cheng Vollmer, Sylvia D. Sakyiama Kwakye , '98, Matthew Evan Halpern , '98, E. Carr Everbach Oct 1998

Bacterial Stress Responses To 1-Megahertz Pulsed Ultrasound In The Presence Of Microbubbles, Amy Cheng Vollmer, Sylvia D. Sakyiama Kwakye , '98, Matthew Evan Halpern , '98, E. Carr Everbach

Engineering Faculty Works

Members of a panel of stress-responsive biosensors have been used to study the effect of megahertz frequency ultrasound onEscherichia coli. Insonification causes acoustic cavitation, the collapse of oscillating microbubbles in solution, which can damage bacterial cells. A focused 1-MHz ultrasound transducer, capable of generating a spatial peak pulse average intensity of 500 W/cm2, was used to treat liquid bacterial cultures. Stress-responsive promoters fused to luxCDABE allowed the continuous measurement of light produced as a result of protein damage, DNA damage, oxidative stress, and membrane perturbation. A promoter responsive to ammonia limitation was not transcriptionally activated under test conditions. In contrast …


Conceptual Breakthroughs In Developmental Biology, Scott F. Gilbert Sep 1998

Conceptual Breakthroughs In Developmental Biology, Scott F. Gilbert

Biology Faculty Works

No abstract provided.


Wormwholes: A Commentary On K.F. Schaffer's "Genes, Behavior, And Developmental Emergentism", Scott F. Gilbert, E. M. Jorgensen Jun 1998

Wormwholes: A Commentary On K.F. Schaffer's "Genes, Behavior, And Developmental Emergentism", Scott F. Gilbert, E. M. Jorgensen

Biology Faculty Works

Although Caenorhabditis elegans was chosen and modified to be an organism that would facilitate a reductionist program for neurogenetics, recent research has provided evidence for properties that are emergent from the neurons. While neurogenetic advances have been made using C. elegans which may be useful in explaining human neurobiology, there are severe limitations on C. elegans to explain any significant human behavior.