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
Polar form of the Dirac equation formula_11 vanish simultaneously, the spinor field is called regular, and in this case it is always possible to find a local frame in which the regular spinor field acquire the form up to a transformation of the type formula_15 and up to the reversal of the third axis. Therefore, a regular spinor can, in general, be written according to where formula_17 is called module and formula_18 is called Yvon-Takabayashi angle, and where formula_19 is the generic complex representations of the Lorentz transformation that is needed to obtain the generic spinor in its most reduced form as is written above. When