The four main types of colostomy to discuss with a doctor include transverse, ascending, descending, and sigmoid. Each is named for the part of the colon in which a surgeon makes the stoma.

This surgical procedure removes the sigmoid colon and connects the descending colon with the anus. It can be done via open or laparoscopic surgery.

Sigmoidal Curve: An S-shaped curve that characterises growth processes which start slowly, accelerate, and then level off as they approach a saturation point.

Amyloid deposition is a hallmark of neurodegenerative diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). The deposition process is described as a sigmoidal curve in which the ...