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
Concerto for Piano, Violin and Strings (Mendelssohn) Concerto for Piano, Violin and Strings (Mendelssohn) The Concerto for Piano, Violin, and Strings in D minor, MWV O4, also known as the Double Concerto in D minor, was written in 1823 by Felix Mendelssohn when he was 14 years old. This piece is Mendelssohn's fourth work for a solo instrument with orchestral accompaniment, preceded by a Largo and Allegro in D minor for Piano and Strings MWV O1, the Piano Concerto in A Minor MWV O2, and the Violin Concerto in D minor MWV O3. Mendelssohn composed the work to be performed for a private concert on May 25,