In arithmetic, rules for addition involving fractions and negative numbers have been devised amongst others. In algebra, addition is studied more abstractly.
Addition has several important properties. It is commutative, meaning that order does not matter, and it is associative, meaning that when one adds more than two numbers, the order in which addition is performed does not matter (see Summation). Repeated addition of 1 is the same as counting; addition of 0 does not change a number. Addition also obeys predictable rules concerning related operations such as subtraction and multiplication.
Gamma-adducin is a protein that in humans is encoded by the ADD3gene.
Adducins are heteromeric proteins composed of different subunits referred to as adducin alpha, beta and gamma. The three subunits are encoded by distinct genes and belong to a family of membrane skeletal proteins involved in the assembly of spectrin-actin network in erythrocytes and at sites of cell-cell contact in epithelial tissues. While adducins alpha and gamma are ubiquitously expressed, the expression of adducin beta is restricted to brain and hematopoietic tissues. Adducin, originally purified from human erythrocytes, was found to be a heterodimer of adducins alpha and beta. Polymorphisms resulting in amino acid substitutions in these two subunits have been associated with the regulation of blood pressure in an animal model of hypertension. Heterodimers consisting of alpha and gamma subunits have also been described. Structurally, each subunit is composed of two distinct domains. The amino-terminal region is protease-resistant and globular in shape, while the carboxy-terminal region is protease-sensitive. The latter contains multiple phosphorylation sites for protein kinase C, the binding site for calmodulin, and is required for association with spectrin and actin. Alternatively spliced adducin gamma transcripts encoding different isoforms have been described. The functions of the different isoforms are not known.
The song was thought of by Sermon after buying a copy of Gaye's Midnight Love and the Sexual Healing Sessions album, which overlook some of the original album's earlier mixes. After listening to an outtake of Gaye's 1982 album track, "Turn On Some Music" (titled "I've Got My Music" in its initial version), Sermon decided to mix the vocals (done in a cappella) and add it into his own song. The result was similar to Natalie Cole's interpolation of her father, jazz great Nat "King" Cole's hit, "Unforgettable" revisioned as a duet. The hip hop and soul duet featuring the two veteran performers was released as the leading song of the soundtrack to the Martin Lawrence & Danny DeVito comedy, "What's the Worst That Could Happen?" The song became a runaway success rising to #2 on Billboard's R&B chart and was #1 on the rap charts. It also registered at #21 pop giving Sermon his highest-charted single on the pop charts as a solo artist and giving Gaye his first posthumous hit in 10 years following 1991's R&B-charted single, "My Last Chance" also bringing Gaye his 41st top 40 pop hit. There is also a version that's played on Adult R&B stations that removes Erick Sermon's rap verses. The song was featured in the 2011 Matthew McConaughey film The Lincoln Lawyer.