photonegative


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photonegative

[¦fōd·ō′neg·ə·tiv]
(electronics)
Having negative photoconductivity, hence decreasing in conductivity (increasing in resistance) under the action of light; selenium sometimes exhibits photonegativity.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The mean percentage of photonegative and photopositive cer cariae at each light intensity was not significantly different from the control (P > 0.05; Fig.
Larval behaviors can also change over time: the larvae of many invertebrate species are photopositive upon release and then become photoneutral or photonegative over time, a change that is often associated with an increase in exploring behavior (e.g., Ryland, 1960; Thorson, 1964; Wendt and Woollacott, 1999).
Given that larvae shift from being photopositive to photonegative with age.
The switch to photonegative behavior prior to metamorphosis would only require downregulation of effector ciliary beat among the same receptor-effector complex.
Most individuals are positively phototactic on release, becoming photonegative after the first several hours of larval swimming (Pires and Woollacott, 1997; Wendt and Woollacott, 1999).
In 76% of the cases examined, larvae that were initially photopositive became photonegative before the end of the larval period.
Larvae are strongly photopositive on release and with time either change to photoneutral or alternate between photopositive and photonegative.
neritina to become photonegative. Antibodies to 5HT label cells with processes that are associated with the apical disc and extend orally to the equatorial nerve-muscle ring.
The books are like photonegatives of each other, as one might guess from the titles.