Asthenosphere Asthenosphere, Layer beneath the lithosphere. The asthenosphere is the layer of our planet that lies beneath the lithosphere. It was first named by J. Barrell, a British geologist when he divided the interior of the Earth into three parts. The lithosphere is the outer layer of the Earth that contains crustal plates.
It is wise, however, to have the test repeated by a different laboratory using a different technique (Western Blot). Mother cats with FIV pass antibody to their kittens whether the kittens become infected or not. So positive test results in kittens do not mean they harbor the virus of FIV. If kittens are positive, they need to be retested every two months until they are six months old to see if the test becomes negative. If the test is still positive at six month, they probably have the disease.
A negative result for either test means that it is likely that the person tested does not have a TB infection. However, it does not entirely rule out tuberculosis. It may mean that the person's immune system has not responded to the antigen in the test or that it is too early to detect exposure. It takes about 6 weeks after infection before a person demonstrates a positive reaction to TB screening tests.