Richard K. Hester

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— A CODEC, fabricated in 3.3-V CMOS, provides the low-voltage transmitter and receiver interfaces between the modem digital signal-processing engine and the high-voltage hybrid circuitry for either the central office or the remote terminal ends of the subscriber loop, configurable by metal mask option. Extensive use of digital interpolation filters in the(More)
AIM To quantitatively assess the effect of lowering external Ca(2+) ([Ca(2+)](o)) on both endothelium-dependent and -independent relaxations in rabbit aorta. METHODS Isometric contractions and relaxations of isolated aortae were recorded. When assessing the effect of reduced [Ca(2+)](o) on relaxations, the normal [Ca(2+)](o) solution was substituted with(More)
Residual responses to norepinephrine (NE) in an Mg2+-, Ca2+-free medium with low EGTA (0.1 mM) for 15 min were potentiated following preincubation of rabbit aortas in Mg2+-free medium for 60 min. Responses to Ca2+ in a Ca2+-free medium with nifedipine and NE were not affected under a similar Mg2+-free condition. Nifedipine, theophylline, dibutyryl cAMP,(More)
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