Synthesis and Photochromism Studies of 1-(2,5-Dimethyl-3-Thienyl)-2-[2-Methyl-5- Pyrenyl-3-Thienyl]Perfluorocyclopentene

A new unsymmetrical photochromic diarylethene1o, which contains condensed nucleus was synthesized. Its photochromic both in hexane solution and in PMMA film and kinetics experiment were investigated in detail. The result indicated that this diarylethene had reversible photochromism, changing the color from colorless to purple in hexane solution upon appropriate irradiation with 297 nm UV light, respectively. What’s more, The kinetic experiments showed that the cyclization and cycloreversion processes were zeroth and first order reaction, respectively. This new photochromic system also exhibited fluorescence switching in acetonitrile solution.

Spermatozoa of the giant octopus of the North Pacific Octopus dofleini martini

Spermatozoa of the giant octopus, as obtained from ruptured metre-long spermatophores, are only feebly motile. The total length of a spermatozoon is 1/2 mm, most of it due to the tail. The sperm-head, slim and oblong, is composed of a highly condensed nucleus and a cork-screw shaped acrosome. A striking feature, which distinguishes octopus spermatozoa from those of mammals, is the presence of a large amount of glycogen, concentrated mainly around the sperm-head. This, together with the occurrence of high phosphorylase and phosphoghlcomutase activity, indicates that glycogenolysis represents a pathway of carbohydrate metabolism in octopus spermatozoa. Both glucose-6-phosphate isomerase and glucose-6-phosphate dehydrogenase were demonstrated in extracts of prepared sperm- homogenates, which suggests that octopus spermatozoa may be capable of metabolizing glucose-6-phosphate along the oxidative as well as the glycolytic pathway.