Vitamin amino acids. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, vitamin E consists of four tocopherols and four tocotrienols. The thirteen vitamins required by human metabolism are: vitamin A (retinols and carotenoids), vitamin B (thiamine), vitamin B (riboflavin), vitamin B (niacin), vitamin B (pantothenic acid), vitamin B (pyridoxine), vitamin B (biotin), vitamin B (folic acid or folate), vitamin B (cobalamins), vitamin C (ascorbic acid), vitamin D (calciferols), vitamin E (tocopherols and tocotrienols), and vitamin K (quinones). Vitamins have diverse biochemical functions. Some forms of vitamin A function as regulators of cell and tissue
Superbird-B2 backup VSAT system to Japanese local government. Following its launch and on-orbit testing, it was placed in geostationary orbit at 162° East, from where it provides communications services to Japan. It is equipped with thirty five transponders. Currently, the J-Alert emergency warning system is broadcast via Superbird-B2. Superbird-B2 Superbird-B2, also known by its pre-launch designation Superbird-4, is a Japanese communications satellite which is operated by SKY Perfect JSAT Group. It was originally built and launched for the Space Communications Corporation, which merged with JSAT in October 2008. It was constructed by Hughes and is based on the HS-601HP satellite bus.