Michelle Tagliamonte, 58, was getting a manicure when she noticed the black lines on her thumb, which signaled the start of a ...

Use precise geolocation data and actively scan device characteristics for identification. This is done to store and access ...

and the thickness can range from resembling a thin pencil mark to a broader, more noticeable band. A black line can also stretch horizontally across the nail (horizontal melanonychia), though this ...