Publications by authors named "Twarog B"

This paper presents a vision system that measures the position of an aircraft relative to the runway (RWY) during a landing approach. It was assumed that all the information necessary for a correct approach was based entirely on an analysis of the image of the runway and its surroundings. It was assumed that the way the algorithm works, as well as possible, should imitate the pilot's perception of the runway.

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Serotonin: history of a discovery.

Comp Biochem Physiol C Comp Pharmacol Toxicol

February 1989

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It would appear that susceptibility to chronic proliferative pulmonary hypertension in response to chronic alveolar hypoxia is most severe in species in which adrenergic innervation of pulmonary arteries is reduced or lacking. Intrapulmonary arteries of the rat have been reported to lack adrenergic innervation by some workers but not others. Since the rat develops severe proliferative pulmonary hypertension in response to prolonged alveolar hypoxia, the different divisions of the lung vasculature of Sprague-Dawley rats were thoroughly examined to determine the presence or absence of an adrenergic innervation.

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Electrical properties of the membrane of smooth muscle cells in the rat main pulmonary artery (MPA) and a small pulmonary artery (SPA) were compared. MPA and SPA differed in several important respects, suggesting characteristic quantitative and qualitative differences in membrane properties. 1) Resting membrane potentials were similar in both (MPA 52.

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The membrane properties of smooth muscle cells in rat main pulmonary artery (MPA) and small pulmonary artery (SPA) were investigated during chronic normobaric hypoxia and after monocrotaline injection. As chronic pulmonary hypertension developed, pronounced differences between MPA and SPA were observed. These findings may shed light on mechanisms of smooth muscle hypertrophy.

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Contractile and relaxing responses of the anterior byssus retractor muscle of Mytilus edulis L. were observed after exposure to La+++. After 25 minutes in 5 mM La+++, contraction in response to acetylcholine, to KCl and to stimulation of intramuscular nerves is blocked, whereas contraction in response to direct current pulses is partially blocked and caffeine contraction is unaffected.

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The effects of mersalyl, bromo-LSD (BOL) and methysergide (UML) on the relaxation of catch by certain indole and catechol derivatives were studied in the anterior byssus retractor muscle of Mytilus. Mersalyl antagonized relaxation in response to serotonin whereas BOL and UML were less effective. Two other indole derivatives, ergotamine and gramine, were also blocked by mersalyl; BOL and UML antagonized relaxation in response to dopamine more effectively than did mersalyl.

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1) Catch in Mytilus ABRM may be a specialization of a mechanism common to all muscles that gives rise to stretch resistance in the resting state. Catch appears to be due to actin myosin interaction. Since this interaction is regulated by nerves, it provides a convenient model for studying resting stretch resistance.

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The individual muscle fibers of the anterior byssus retractor muscle (ABRM) of Mytilus edulis L. are uninucleate, 1.2-1.

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1. In the nerve-muscle preparation, where catch was characteristically minimal, 5-hydroxytryptamine (5-HT) had no effect on resting membrane potential, junction potentials, spikes or contraction.2.

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