Propolis recently been isolated from red propolis, and prenylated acids such as 4-hydroxy-3,5-diprenyl cinnamic acid have been documented. An analysis of propolis from Henan, China found sinapinic acid, isoferulic acid, caffeic acid, and chrysin, with the first three compounds demonstrating antibacterial properties. Also, Brazilian red propolis, largely derived from "Dalbergia ecastaphyllum" plant resin, has high relative percentages of the isoflavonoids 3-hydroxy-8,9-dimethoxypterocarpan and medicarpin. Other flavonoids commonly present include galangin and pinocembrin. Caffeic acid phenethyl ester (CAPE) is also a component of some varieties of propolis from New Zealand. Occasionally, worker bees will even gather various caulking compounds of human manufacture, when
Stitch and glue As such, unlike other construction techniques of the day, which required specialist skills and tools, Stitch and Glue was supposed to put boat-building within the reach of the average public. Although stitch and glue is similar to a traditional form of boatbuilding from northern Europe, particularly Lapland, called "sewn boats", it is not known if Littledyke's development of the stitch and glue methods was influenced by that technique. In the United States stitch and glue boat building was popularized in the mid-1980s largely through Harold "Dynamite" Payson's articles in "WoodenBoat" magazine and books on building "instant boats" designed by Phil