Biodegradable polymer which, edible films have gained more attention due to their environmentally-friendly characteristics, vast variety and availability, non-toxicity, and low cost. Biodegradable polymers have a long history, and since many are natural products, the precise timeline of their discovery and use cannot be accurately traced. One of the first medicinal uses of a biodegradable polymer was the catgut suture, which dates back to at least 100 AD. The first catgut sutures were made from the intestines of sheep, but modern catgut sutures are made from purified collagen extracted from the small intestines of cattle, sheep, or goats. The concept of synthetic
Experimental musical instrument the length of the long strings and rubbing them with rosined hands and producing longitudinal vibrations. Bradford Reed invented the pencilina, a custom-made string instrument in the 1980s. It is a double-neck 3rd bridge guitar that is similar in construction to two long, thin zithers connected by a stand. Wedged over and under the strings in each neck is an adjustable rod, a wooden drum stick for the guitar strings and a metal rod for the bass strings. In addition, there are four bells. The pencilina is played by striking its strings and bells with sticks. The strings may also