Lastly, parietal cells synthesizedand secrete intrinsic factor which aids in the absorption of vitamin B12 by the ileum. Chief cells (B or arrow)are located, in cluster, at the base of the glands. They synthesize and secret hydrolytic enzymes, which areactivated at acid pH. These enzymes include gastric lipase, rennin and pepsin, which is secreted aspepsinogen and activated in the lumen. Pepsin hydrolyzes proteins. Rennin breaks down milk proteins andlipase initiates the digestion of fats.
A basis set in theoretical and computational chemistry is a set of functions (called basis functions) which are combined in linear combinations (generally as part of a quantum chemical calculation) to create molecular orbitals.
The Canonical Partition Function is the ( Boltzmann ) weighted sum of the microstates of any system. The partition function is also a combinatorial generating function. See this great book on Generating Functionology. https://www.math.upenn.edu/~wilf... The partition function has lots of applications. In particular, we can use it to express the important global variables that describe a system, such as the Total Energy, the Free Energy, the Entropy, the Variance, etc.