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OBJECT Exogenous progesterone has been shown to reduce brain edema and ischemia-induced cell damage and to improve physiological and neurological function during the early stage of focal cerebral ischemia. In the present study, the authors assessed the neuroprotective potential of progesterone during the late stage of ischemia in a transient middle cerebral(More)
Sun-synchronous exploration is accomplished by reasoning about sunlight: where the Sun is in the sky, where and when shadows will fall, and how much power can be obtained through various courses of action. In July 2001 a solar-powered rover, named Hyperion, completed two sun-synchronous exploration experiments in the Canadian high arctic (75°N latitude).(More)
Plasma vasopressin concentrations, measured by radioimmunoassay, were remarkably elevated during endotoxin and E. coli shock. The concentrations were often above 500 pg/ml in dogs and above 300 pg/ml in baboons; they reached 1200 pg/ml in two dogs and 1800 pg/ml in another. Plasma concentration in a quiet, hydrated subject is 4 pg/ml; osmoregulation is(More)
Plasma vasopressin concentration was measured by radioimmunoassay in lightly anesthetized baboons and dogs before and during experimental Escherichia coli septic shock. Since vasopressin is a potent vasoconstrictor, and activator of clotting factors and a myocardial depressant, we postulated that, if found in substantial amounts in the plasma, vasopressin(More)
To eliminate the influence of anesthesia while investigating the role of vasoactive hormones during shock, we have developed an unanesthetized rat model that provides information on key cardiovascular parameters pertinent to shock. Enfluane anesthesia was used while the animals were being catheterized. After recovery from anesthesia, endotoxin (40 mg/kg)(More)
The Atacama Desert of northern Chile may be the most lifeless place on Earth, yet microorganisms do survive in some areas. The distribution and diversity of life in the Atacama remains unexplored and is the focus of the Life in the Atacama project. To conduct this investigation, survey traverses across the desert with biologic and geologic instruments will(More)
To study life in the Mars-like Atacama Desert of Chile we have created a robot, Zoë, and conducted three seasons of technical and scientific experiments. We describe Zoë's exploration algorithms and architecture and assess a total of six months of long distance survey traverses. To date Zoë has navigated autonomously over 250 km. Its average distance per(More)