1.   Aggressive factors include gastric juice and bile salts which can reflux back into the stomach.

2.   Other limiting factors include unions, large customers and suppliers, and government.

3.   These factors include leaving parental home, Marriage, fertility history, occupational change, retirement and sickness in old age.

4.   These variable factors include the depth of the water, its temperature and transparency, and its velocity, among others.

5.   These factors include funding sources, the employment market for successful graduates, and the costs of running university departments.

6.   Such factors include Reduced utilization.

7.   Procoagulant factors include lipoprotein that contains plasminogen-like domains that allow it to compete with plasminogen for binding sites on endothelial cells, thus impairing fibrinolysis.