Circuits are grounded for the. purpose of limiting the voltage upon the circuit which might. otherwise occur through exposure to lightning or other voltages. higher than that for which the circuit is designed; or to limit. the maximum potential to ground due to normal voltage. (b) Exposed Enclosures.
More important, there are differences in the underlying cause of these two types of heart attack and, therefore, in the initial treatment. A STEMI heart attack is caused when a blood clot suddenly forms, completely blocking an artery in the heart. This can result in damage that covers a large area of the heart and extends deep into the heart muscle.
TIAs are usually caused by a clot that blocks blood flow. Plaque, often called atherosclerosis, can build up in your arteries, narrowing the space blood flows through or causing a clot to develop. Some other conditions that can cause TIAs include: 1  A weakened, bulging heart wall (ventricular aneurysm). 2  A rapid, irregular heartbeat (atrial fibrillation). 3  Narrowing of the main artery in your neck, the carotid artery. 4  Blood clotting problems.