Rigour (BrE) or rigor (AmE) (see spelling differences) describes a condition of stiffness or strictness. Rigour frequently refers to a process of adhering absolutely to certain constraints, or the practice of maintaining strict consistency with certain predefined parameters.
PLA stands for polylactic acid and is a resin made from corn starch. PLA is used to make clear compostable containers and PLA lining is used in cups and containers as an impermeable liner. PLA is biodegradable, and fully compostable. It uses 65 percent less energy to produce than conventional oil-based plastics and generates 68 percent fewer greenhouse gasses and contains no toxins.
Prostate Specific Antigen Test. The Prostate Specific Antigen (PSA) test is a common screening for prostate cancer. This test measures a protein that is produced by the prostate gland. Elevated PSA levels may indicate a higher likelihood of having prostate cancer. The PSA test is also used to monitor a person's response to cancer treatment.