Solar azimuth angle be interpreted as the angle between zero and 180 degrees when the hour angle, "h", is negative (morning) and the angle between 180 and 360 degrees when the hour angle, "h", is positive (afternoon). (These two formulas are equivalent if you assume the "solar elevation angle" approximation formula). The formulas use the following terminology: Solar azimuth angle The solar azimuth angle is the azimuth angle of the Sun's position. This horizontal coordinate defines the Sun's relative direction along the local horizon, whereas the solar zenith angle (or its complementary angle solar elevation) defines the Sun's apparent altitude. There are several
Straight leg raise more specific, the ankle can be dorsiflexed and the cervical spine flexed. This increases the stretching of the nerve root and dura. If the patient experiences sciatic pain when the straight leg is at an angle of between 30 and 70 degrees, then the test is positive and a herniated disk is a possible cause of the pain. A negative test suggests a likely different cause for back pain. A meta-analysis reported the accuracy as: If raising the opposite leg causes pain (cross or contralateral straight leg raising): Lasègue's sign was named after Charles Lasègue (1816-1883). In 1864 Lasègue described