RESUMO
Gravitational-wave detectors such as Virgo and the laser interferometric gravitational-wave observatory (LIGO) use a long-baseline Michelson interferometer with Fabry-Perot cavities in the arms to search for gravitational waves. The symmetry between the two Fabry-Perot cavities is crucial to reduce the interferometer's sensitivity to the laser amplitude and frequency noise. To this purpose, the transmittance of the mirrors in both cavities should be as close as possible. This paper describes the realization and the characterization of the first twin large low-loss mirrors with transmissions differing by less than 0.01%.
RESUMO
The effect of altered gravity on single cells has been reported in a number of studies. From the investigation of the immune system response to spaceflight conditions, interest has focused on the influence of gravity on single lymphocytes. Microgravity has been shown to decrease lymphocyte activation and to influence motility. On the other hand, the effect of hypergravity on lymphocyte motility has not been explored. We studied the migration of human peripheral blood T lymphocytes cultured in vitro in a hypergravity environment (10g). After hypergravity culture for 1-11 days, T cells were seeded on a fibronectin-coated glass surface, observed by time-lapse bright-field microscopy, and tracked by a computer program. We found that T cells, activated and then cultured in hypergravity, become motile earlier than cells cultured at normal gravity. These results suggest that hypergravity stimulates T cell migration.
