Without variable valve timing or variable valve lift, the valve timing must be the same for all engine speeds and conditions, therefore compromises are necessary. An engine equipped with a variable valve timing actuation system is freed from this constraint, allowing performance to be improved over the engine operating range.
A variety of medical specialists treat people with osteoporosis, including internists, gynecologists, family doctors, endocrinologists, rheumatologists, physiatrists, orthopaedists, and geriatricians. There are a number of ways to find a doctor who treats osteoporosis patients. If you have a primary care or family doctor, discuss your concerns with him or her. Your doctor may treat the disease or be able to refer you to an osteoporosis specialist.
A doctor of osteopathy (D.O.), or an osteopath is a physician who deals with the structure and function of the body, and uses manipulations to help the body heal itself. This holistic approach relies on all the neuromusculoskeletal systems of the body as an integral part of health.