Open Access. Powered by Scholars. Published by Universities.®
- Discipline
- Keyword
-
- Blackbody radiation (1)
- DNA transcription (1)
- Digital simulation (1)
- Evolutionary adapation (1)
- Evolutionary genetics (1)
-
- Genome evolution (1)
- Heat transfer (1)
- Insertion mutation (1)
- Laser cooling (1)
- Los Alamos National Laboratory (1)
- Mirrors (1)
- Mutation (1)
- Optical engineering computing (1)
- Optical pumping (1)
- Optical testing (1)
- Optical waveguides (1)
- Osmotic shock (1)
- Quantum optics (1)
- Radiation pressure (1)
- Refrigeration (1)
- Regulatory networks (1)
- Solid lasers (1)
- Thermal analysis (1)
- Wave guides (1)
Articles 1 - 2 of 2
Full-Text Articles in Life Sciences
Thermal Links For The Implementation Of An Optical Refrigerator, John Parker, David Mar, Steven Von Der Porten, John Hankinson, Kevin Byram, Chris Lee, Michael K. Mayeda, Richard C. Haskell, Qimin Yang, Scott R. Greenfield, Richard I. Epstein
Thermal Links For The Implementation Of An Optical Refrigerator, John Parker, David Mar, Steven Von Der Porten, John Hankinson, Kevin Byram, Chris Lee, Michael K. Mayeda, Richard C. Haskell, Qimin Yang, Scott R. Greenfield, Richard I. Epstein
All HMC Faculty Publications and Research
Optical refrigeration has been demonstrated by several groups of researchers, but the cooling elements have not been thermally linked to realistic heat loads in ways that achieve the desired temperatures. The ideal thermal link will have minimal surface area, provide complete optical isolation for the load, and possess high thermal conductivity. We have designed thermal links that minimize the absorption of fluoresced photons by the heat load using multiple mirrors and geometric shapes including a hemisphere, a kinked waveguide, and a tapered waveguide. While total link performance is dependent on additional factors, we have observed net transmission of photons with …
Compensatory Evolution Of Gene Regulation In Response To Stress By Escherichia Coli Lacking Rpos, Daniel M. Stoebel, Karsten Hokamp, Michael S. Last, Charles J. Dorman
Compensatory Evolution Of Gene Regulation In Response To Stress By Escherichia Coli Lacking Rpos, Daniel M. Stoebel, Karsten Hokamp, Michael S. Last, Charles J. Dorman
All HMC Faculty Publications and Research
The RpoS sigma factor protein of Escherichia coli RNA polymerase is the master transcriptional regulator of physiological responses to a variety of stresses. This stress response comes at the expense of scavenging for scarce resources, causing a trade-off between stress tolerance and nutrient acquisition. This trade-off favors non-functional rpoS alleles in nutrient-poor environments. We used experimental evolution to explore how natural selection modifies the regulatory network of strains lacking RpoS when they evolve in an osmotically stressful environment. We found that strains lacking RpoS adapt less variably, in terms of both fitness increase and changes in patterns of transcription, than …