But new Johns Hopkins research in mice suggests that neural stem cells, the bodyâs source of new brain cells, are resistant to radiation, and can be roused from a hibernation-like state to reproduce and generate new cells able to migrate, replace injured cells and potentially restore lost function.
Pupillary Distance (PD) You'll need to know your PD if you want to order glasses from EyeBuyDirect. Don't worry if your glasses prescription doesn't include your PD, we can show you how to measure it by yourself. How to measure your pd
Safety glasses (spectacles) are commonly used as protection against impact and optical radiation. Tinted safety glasses used in torch soldering must have a shade number (1.5-3) on the lens, but do not provide adequate protection for gas or arc welding which need shades 4 or higher.