Lung VQ Scan. Also known as lung or pulmonary ventilation (V) and perfusion (Q) scans. A lung VQ scan is an imaging test that uses a ventilation (V) scan to measure air flow in your lungs and a perfusion (Q) scan to see where blood flows in your lungs. It uses special x ray scanners outside of your body to create pictures of air and blood flow patterns in your lungs.
Yellow leaf spot, also known as leaf septoria, are caused by Septoria cannabis and S. neocannabina. These are fungal pathogens aimed specifically at marijuana plants. It is brought about by warm weather and rain and effect marijuana grown outdoors.
Spotted, dark colors on leaves are an indication of serious problems with your plant. Plant leaves turn black for a number of reasons, including environmental factors and bacterial infections. In some cases the plant is salvageable. However, most of the problems that cause black leaves in plants are irreversible. In every case, prevention is the best way to deal with the disease and dehydration that are common factors in blackened leaves.