UV Light Causes Specific Types of Dark Spots. 1  Melasma: Itâs a common condition characterized by grayish patches on the face, forehead or on the upper lip. 2  Solar Lentigines â Freckles: These are red or brown raised spots caused by long term exposure to the sunlight. 3  Ephelides: These fall under the category of freckles.
What is the antibody titer test? The antibody titer is a test that detects the presence and measures the amount of antibodies within a personâs blood. The amount and diversity of antibodies correlates to the strength of the bodyâs immune response.
A specific example is a viral titer, which is the lowest concentration of virus that still infects cells. To determine the titer, several dilutions are prepared, such as 10 â1, 10 â2, 10 â3, ...10 â8.iters are sometimes expressed by the denominator only, for example 1:256 is written 256. The term has also two other, conflicting meanings. In titration, the titer is the ratio of actual to nominal concentration of a titrant, e.g. a titer of 0.5 would require 1/0.5 = 2 times more titrant than nominal.