Human reproductive ecology to aid infant survival and growth. Lactational strategies vary cross-culturally, but can typically be defined by sibling sets and sex ratios, frequency of nursing, entire lactational duration, and milk composition. Milk is composed of my bioconstituents, but only a few will be outlined here. In the first days of puerperium, the first milk is thick and yellowish, also called colostrum. For weeks after that, mature milk is expressed and it has been shown that fetal-mammary gland signaling occurs even before birth in determining milk type and concentrations based on the fetus sex. Colostrum plays an important role in establishing the
Conjunctive normal form formula_30 and formula_31 with a new variable, and repeating as often as necessary. To convert first-order logic to CNF: As an example, the formula saying ""Anyone who loves all animals, is in turn loved by someone"" is converted into CNF (and subsequently into clause form in the last line) as follows (highlighting replacement rule redices in formula_71): Informally, the skolem function formula_72 can be thought of as yielding the person by whom formula_60 is loved, while formula_74 yields the animal (if any) that formula_60 doesn't love. The 3rd last line from below then reads as ""formula_60 doesn't love the animal