Casting flight

T. Baker, Upwind flight and casting flight complimentary phasic and tonic systems used for location of a sex pheromone sources by male moths, Proceedings of the 10th Intemation Symposium on Olfaction and Taste, (1990), pp. 18-25. 

The timescale over which the moths reactions to pheromone strands and clean air occur is remarkably small. The behavioral responses to both the onset (upwind surge) and loss of filaments (cross-wind casting) can be as fast as 0.15 s in Grapholita molesta (Busck) (Baker and Haynes 1987), but usually are between 0.3 and 0.6 s Vickers and Baker 1997). In studies of host-odor responses by flying female moths, only the latency of the casting flight response to loss of the odor has been measured, and its time course is similar to that of the latency for pheromone loss, 0.7 s (Haynes and Baker 1989). 

Because of its motor, i.e., activating effect on vascular smooth muscle and its inhibitory effect on intestinal smooth muscle, the sympathetic nervous system has been cast into the role of the component of the nervous system that executes control of visceral function in times of physical emergency for the organism. The phrase fight or flight has been often used to describe the circumstances in which the adrenergic transmitters of the sympathetic system are dominant over the cholinergic parasympathetic system. This concept is perhaps oversimplified but it has the utility of a first approximation of how the two components of the ANS interact in the periphery. Sensory inputs which lead to increased blood pressure, for example, activate the sympathetic pathways. 

Fig. 6 Electron time-of-flight photocurrent transients of solution-cast film of EHO-OPPE (L=8 pm), measured at 295 K and an electric field of 2.5-10 V cm in (a) linear and (b) double logarithmic plots. Reproduced with permission from [61]...

The artificial discretization of space, however, is awkward. In particular, it is responsible for introducing a large set of constants w A as a substitute for the diffusion coefficient D. This difficulty is even more serious if one has to take into account the free flight in space of the particles, as in the case of neutrons in a reactor, see 4. Hence it is desirable to cast (1.1) and (1.2) in a form in which the spatial coordinates occur as continuously varying parameters instead of the discrete subscripts k. 

But there was i thing to do but go on No longer worried about keeping quiet, I went to the second door. When I opened it I was looking at the top of a narrow flight of steps. Above them a feeble light bub cast a sickfy illumination... 

Screws for ordinary service customarily consist of steel ribbons wound helically around the central steel shaft or pipe, but for severe service and handling heavy loads the flights are made much heavier, usually of steel, but occasionally of cast iron. The screws are supported by a series of bearings spaced from 6 to 10 ft. centers and the troughs are closed at the charging end. The standard pitch is approximately equal to the diameter of the screw. 

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