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 (PSA) is a protein produced by the prostate and found in the blood. A PSA blood test can detect prostate cancer early, but it may not save lives. Sound confusing? It is. Many prostate cancers grow slowly, so a PSA test may save the lives of some men while causing others to have unnecessary surgeries or radiation treatments, which could cause lifelong problems such as erectile dysfunction or incontinence.