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.
ATT Validity Dates. 1  Each ATT is valid for a period of time specified by the BON/RB (the average length of an ATT is 90 days). 2  Once the BON/RB has declared you eligible to test and you receive your ATT, you must test within the validity dates on the ATT.
On Test Day, you will see anywhere from 75 to 265 questions and have up to 6 hours to complete the exam. The NCLEX-PNÂ® exam is pass/fail based on your ability to answer passing-level questions correctly. On Test Day, you will see anywhere from 85 to 205 questions and have up to 6 hours to complete the exam.