Joel O. Johnson

Learn More
[1] Amphitheater-headed valleys on Earth and Mars are often assumed to result from erosion by emerging spring water (i.e., seepage erosion or groundwater sapping) rather than by surface runoff. The origin of such valleys has implications for landscape evolution on Earth and the hydrologic cycle and associated potential for life on other planets. In this(More)
In this paper, we investigate the ability of fuzzy to adapt the parameters of a pharmacokinetic and pharmacodynamic model-based controller for the delivery of the muscle relaxant pancuronium. The system uses the model to control the rate of drug delivery and uses feedback from a sensor which measures muscle relaxation level to adapt the model using fuzzy(More)
A specialized taxonomy of the autonomic nervous system (ANS) has been developing since the time of Galen (ad 130-200). In the early 1900s, Langley first referred to the ANS. 1 He used the term sympathetic nervous system (SNS) as described by Willis in 1665, and introduced the second division as the parasympathetic nervous system (PNS) in 1921. 2 Although(More)
A functional link between the cannabinoid and opioid receptor pathways has been proposed based on data showing that cannabinoid effects can be blocked by opioid receptor antagonists and that cannabinoids can bind to opioid receptors. To explore this link in more detail at the receptor level, we tested the hypothesis that cannabinoids directly activate or(More)
  • 1