0000000000422151
AUTHOR
Jorge Martinez
A New Multicast Technique for Video Transmission over ABR Services in ATM Networks
Multicast techniques are the only way to simultaneously provide flows of information from one source to several destinations. The intention of this paper is to study and to evaluate different multicast techniques using a video coder based on an adaptive video compression algorithm with subband coding and a best effort network service like ATM with the Available Bit Rate (ABR) service. This video transmission can adapt faster and easily to changing network conditions. In this way, we present an evaluation process for a determined network configuration. Thereafter we discuss the results obtained by simulation and propose for this video transmission a trade-off between these multicast techniqu…
Biotransformation in vitro of the 22R and 22S epimers of budesonide by human liver, bronchus, colonic mucosa and skin.
The pharmacological effects of glucocorticoids are greatly influenced by their pharmacokinetic properties. In the present report, the in vitro biotransformation of the 22R and 22S epimers of the topical steroid budesonide was studied in the S-9 fraction of human liver, bronchus, skin and colonic mucosa. The disappearance of unchanged epimers of budesonide was measured during 90 min of incubation by high performance liquid chromatography. The rate of disappearance was high in human liver while little biotransformation occurred in bronchial tissue and colonic mucosa, and none was detected in the skin. A marked decay of the initial concentration of unchanged budesonide epimers was noticed afte…