Ukulele Festival Hawaii. This annual Waikiki festival honors Hawaii's beloved musical instrument. Photo: Tina Mahina. Photo: Tina Mahina. The ukulele is Hawaiiâs best-loved musical instrument, so it makes sense that Ukulele Festival Hawaii is the worldâs largest, attracting enthusiasts from as far away as Italy and Thailand.
atrioventricular (AV) valve, a valve in the heart through which blood flows from the atria to the ventricles. The valve between the left atrium and left ventricle is the mitral (bicuspid) valve; the right AV valve is the tricuspid valve. 1  Facebook. 2  Twitter.
The two atrioventricular (AV) valves are one-way valves that ensure that blood flows from the atria to the ventricles, and not the other way. The two semilunar (SL) valves are present in the arteries leaving the heart; they prevent blood from flowing back into the ventricles.