There are two models of protein folding that are currently being confirmed: 1  The diffusion collision model, in which a nucleus is formed, then the secondary structure is formed, and finally these secondary structures are collided together and pack tightly together.
If you do not test within these dates you will have to reregister and repay the examination fee. The ATT contains your authorization number, candidate identification number and an expiration date. You need the ATT to: Schedule an appointment to take the NCLEX examination.
1 Call NCLEX Candidate Services if you've lost your ATT or if you have not received your ATT two weeks after registering. 2  The ATT contains the authorization number, candidate identification number and an expiration date. 3  These validity dates cannot be extended for any reason.