ANF

ANF is an acronym used in several fields, and its meaning depends on context. The two most common references are Algebraic Normal Form in boolean algebra and Atrial Natriuretic Factor, an early name for the hormone now called atrial natriuretic peptide.

In boolean algebra, Algebraic Normal Form expresses a Boolean function as a polynomial over the finite field GF(2). Addition is performed by XOR and multiplication by AND. Each term is a product of distinct input variables, and coefficients are in {0,1}. Every Boolean function has a unique ANF representation, which can be computed from a truth table via the Möbius transform. ANF is used in digital logic analysis and synthesis, and in cryptography to study algebraic degree and resistance to certain attacks.

In physiology, ANF stands for Atrial Natriuretic Factor, an early term for the hormone now commonly called atrial natriuretic peptide (ANP). It is produced primarily by atrial cardiomyocytes and helps regulate blood volume and arterial pressure by promoting natriuresis and diuresis and by inducing vasodilation. Its effects are mediated through natriuretic peptide receptors, which raise cyclic GMP levels. ANP plays a role in fluid balance, cardiovascular homeostasis, and response to volume expansion; the term ANF appears mainly in historical literature.

Because ANF has multiple meanings, its intended interpretation is determined by domain and context.