Breastfeeding that is needed for a baby's growth and development. Breastfeeding triggers biochemical reactions which allows for the enzymes, hormones, growth factors and immunologic substances to effectively defend against infectious diseases for the infant. The breast milk also has long-chain polyunsaturated fatty acids which help with normal retinal and neural development. The composition of breast milk changes depending on how long the baby nurses at each session, as well as on the child's age. The first type, produced during the first days after childbirth, is called "colostrum". Colostrum is easy to digest although it is more concentrated than mature milk. It
Sesquilinear form to is Similarly, is orthogonal to with respect to , written (or simply if can be inferred from the context), when . This relation need not be symmetric, i.e. does not imply (but see "" below). A sesquilinear form is reflexive if, for all , That is, a sesquilinear form is reflexive precisely when the derived orthogonality relation is symmetric. A -sesquilinear form is called -Hermitian if there exists such that, for all , If , the form is called -"Hermitian", and if , it is called -"anti-Hermitian". (When is implied, respectively simply "Hermitian" or "anti-Hermitian".) For a nonzero -Hermitian