The diseases have been categorized as patches (cause dead spots or patches in the lawn), rings (cause rings of dead or affected grass), or leaf blight (affect individual blades of grass, often over a wide area and no distinct patch or ring pattern may be noticeable).
PVR, abbreviation for pulmonary vascular resistance. To measure changes in blood vessel size or changes in gas volume in the lungs to assist in diagnosing diseases such as deep vein thrombosis (DVT), chronic obstructive pulmonary disease (COPD), and some peripheral vascular disorders. Veins, arteries, and lungs. None.
Polyvinyl chloride, more correctly but unusually poly(vinyl chloride), commonly abbreviated PVC, is the third-most widely produced synthetic plastic polymer, after polyethylene and polypropylene.PVC comes in two basic forms: rigid (sometimes abbreviated as RPVC) and flexible.The rigid form of PVC is used in construction for pipe and in profile applications such as doors and windows. It is also used for bottles, other non-food packaging, and cards (such as bank or membership cards).VC comes in two basic forms: rigid (sometimes abbreviated as RPVC) and flexible. The rigid form of PVC is used in construction for pipe and in profile applications such as doors and windows. It is also used for bottles, other non-food packaging, and cards (such as bank or membership cards).