Manufacturers have succeeded in selling this technology by emphasizing its energy efficiency and other benefits. The installed cost of VRF systems is about $18 per square foot of conditioned space, while a conventional air-source heat pump system costs about $12 to $15 per square foot.anufacturers have succeeded in selling this technology by emphasizing its energy efficiency and other benefits. The installed cost of VRF systems is about $18 per square foot of conditioned space, while a conventional air-source heat pump system costs about $12 to $15 per square foot.
Essential Thrombocythemia. Essential thrombocythemia (ET) is a type of blood cancer known as a myeloproliferative neoplasm. It involves the abnormal development and function of bone marrow cells that produce blood cells, and leads to the overproduction of blood cells known as platelets.
In this condition, faulty stem cells in the bone marrow make too many platelets. What causes this to happen usually isn't known. When this process occurs without other blood cell disorders, it's called essential thrombocythemia. A rare form of thrombocythemia is inherited. (Inherited means the condition is passed from parents to children through the genes.) In some cases, a genetic mutation may cause the condition. In addition to the bone marrow making too many platelets, the platelets also are abnormal in primary thrombocythemia. They may form blood clots or, surprisingly, cause bleeding when they don't work well. Bleeding also can occur because of a condition that develops called von Willebrand disease.