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
PD In order to customize your glasses, you have to figure out your PD, or pupillary distance, aka, the distance between your pupils. Once we have this information, we can determine how to place your lenses in your frame. Just ask your optician; they should have your PD on file. You can also measure your PD yourself.