Joel O. Johnson

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The present experiments examined the role of the serotonergic system in the behavioral deficit produced by uncontrollable shock. In Experiment 1: Establishment of model, the behavioral potential of the Sprague-Dawley rat was defined. When exposed to mild uncontrollable stress such as a 0.8 mA electric footshock, a significant percentage of rats developed a(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)
OBJECTIVE This pilot study provides firsthand feedback from medical students and residents in training regarding their perceptions of technology in medicine. METHOD The authors distributed an e-mail invitation to an anonymous Web-based survey to medical students and residents in two different U.S. training institutions. RESULTS Respondents unanimously(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)
Chromosome 22q11.2 deletion syndrome (22q11.2DS) is a result of a hemizygotic microdeletion that results in a variety of impairments in children including greater risk for psychiatric ailments in adulthood. We used high-resolution magnetic resonance imaging to accurately quantify the length and, for the first time, volume, of the cavum septum pellucidum(More)
Author Information Stiff-person syndrome (SPS) is a rare neurologic disease manifested by persistent muscle contractions causing marked rigidity in the affected individual [1]. There are many case descriptions and clinical reviews in the neurologic literature, outlining a progression of knowledge from the early clinical description of SPS to advanced(More)
BACKGROUND Changes in cardiac output may occur during insufflation for laparoscopic procedures. However, there are limited data regarding its potential effects on cerebral oxygenation. MATERIALS AND METHODS Cerebral oxygenation (ScO(2)), end tidal CO(2), heart rate, blood pressure and oxygen saturation by pulse oximetry were recorded every 5 minutes prior(More)