Natural fiber Keratin is a structural protein located at the hard surfaces in many vertebrates. Keratin has two forms, α-keratin and β-keratin and are used by different classes of animals. The naming convention for proteins follows that for keratin, alpha keratin is helical and beta keratin is sheet like. Alpha keratin is found in mammalian hair, skin, nails, horn and quills, while beta keratin can be found in avian and reptilian species in scales, feathers, and beaks. The two different structures of keratin have dissimilar mechanical properties, as seen in their dissimilar applications. The relative alignment of the keratin fibrils has a
Debra Nails Debra Nails Debra Nails (born November 15, 1950) is an American philosophy professor and well known classics scholar who taught at Michigan State University. Nails earned her M.A. in philosophy and classical Greek from Louisiana State University before going on to earn a Ph.D. in philosophy at the University of the Witwatersrand, Johannesburg in 1993. Previously, she taught in the Department of Classics, Philosophy, and Religion at Mary Washington College. Nails taught courses on the history of philosophy, continental rationalism, metaphysics, and modern philosophy. Nails' work primarily focuses on ancient Greek philosophy, metaphysics, feminist philosophy, and early modern philosophy. She