Seed Discharge in Arceuthobium: A Photographic Study
Photographs, made at a speed of 5 microseconds, of the ejection of the Arceuthobium seed from its fruit, show that tumbling in the vertical plane begins soon after discharge and that most seeds have turned 90 degrees when they have traveled about 6 centimeters. As the seeds leave the fruit they have a viscous sheath around the trailing end that disintegrates after the seeds have traveled about 2 to 3 centimeters. This viscous material does not act as a rudder as has been postulated.
Acetylcholine Effects of γ-Carbomethoxypropyltrimethyl-Ammonium Bromide
γ-Butyrobetaine, in comparison with its methyl ester, γ-carbomethoxypropyltrimethyl-ammonium bromide, is biologically inert. When injected into mice and insects or assayed on the frog's rectus abdominis muscle, γ-carbomethoxypropyltrimethyl-ammonium bromide has pharmacological properties resembling those of acetylcholine. Although reported to be present in rat brain during the convulsions induced by dieldrin poisoning, γ-butyrobetaine has not been found in the nervous tissue of the roach after treatment with dieldrin.
Line Arrester Energy Discharge Duties
Surge arresters could practically eliminate lightning flashovers on distribution lines, if they are properly deployed in large enough numbers, and if they could survive the current and energy discharge duties imposed by high-magnitude lightning strokes. The discharge duty depends on complex interactions between the arrester locations, grounding, shielding from nearby objects, and the local lightning environment. But many factors of traditional concern with distribution arrester application, such as the lead length, surge front time, and protective margin, play little or no role in the discharge duty. Probabilistic methods determine the expected arrester failure rate. This should be much lower than the original flashover rate on the line insulation, otherwise the design is not acceptable. A transient program such as EMTP/ATP provides the best tool for calculating the discharge duty, but simplified methods are also available