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
If you have a single PD number, which would be one number between 50 and 75, subtract three. For example, letâs say your distance vision PD is 63. Lower this by three, to 60, for single-vision reading glasses. However, you may have a dual PD, which is the measurement from the center of each pupil to the center of the bridge of your nose. In this case, you would have two numbers, each somewhere between the mid-20s to the mid-30s.