photopositive


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photopositive

[¦fōd·ō′päz·əd·iv]
(electronics)
Having positive photoconductivity, hence increasing in conductivity (decreasing in resistance) under the action of light; selenium ordinarily has photopositivity.
References in periodicals archive ?
Light traps may collect a larger proportion of settlement-stage larvae for those fishes that exhibit a photopositive response, but they catch fewer taxa and
Larvae are strongly photopositive on release and with time either change to photoneutral or alternate between photopositive and photonegative.
We report that 5HT and its immediate metabolic precursor, 5-hydroxytryptophan (5HTP), rapidly caused photopositive larvae of B.
In controls without applied 5HT, the percentage of larvae remaining photopositive decreased from a mean of 88% to 70% over the 140-min period.
In controls lacking exogenous DA, the percentage of larvae remaining photopositive decreased from a mean of 83% to 41% over 240 min.
6] M 5HT rapidly induced negative phototaxis in newly released photopositive larvae of B.
The sharp initial decrease in the percentage of photopositive larvae seen after treatment with [10.
neritina remain photopositive for 2-3 h (see controls in [ILLUSTRATION FOR FIGURE 2 OMITTED]), then make a transition to a state in which they alternate between positive and negative phototaxis (Ryland, 1960), and eventually may become photonegative (Mawatari, 1951).