Thioglycolic acid corresponding disulfide (2-[(carboxymethyl)disulfanyl]acetic acid or dithiodiglycolic acid): Thioglycolic acid, usually as its dianion, forms complexes with metal ions. Such complexes have been used for the detection of iron, molybdenum, silver, and tin. Thioglycolic acid reacts with diethyl acetylmalonate to form acetylmercaptoacetic acid and diethyl malonate, the reducing agent in conversion of Fe(III) to Fe(II). Scientist David R. Goddard, in the early 1930s, identified TGA as a useful reagent for reducing the disulfide bonds in proteins, including keratin (hair protein), while studying why protease enzymes could not easily digest hair, nails, feathers, and such. He realized that while the disulfide bonds,
Facial hair developing facial hair, especially after menopause, though typically significantly less than men. Men may style their facial hair into beards, moustaches, goatees or sideburns; others completely shave their facial hair. The term "whiskers", when used to refer to human facial hair, indicates the hair on the chin and cheeks. The moustache forms its own stage in the development of facial hair in adolescent males. Facial hair in males does not always appear in a specific order during puberty and varies among some individuals but may follow this process: Depending on the periods and countries, facial hair was prohibited in the