In step 2 of an electrophilic addition, the positively charged intermediate combines with (Y) that is electron-rich and usually an anion to form the second covalent bond.Step 2 is the same nucleophilic attack process found in an SN1 reaction.n step 2 of an electrophilic addition, the positively charged intermediate combines with (Y) that is electron-rich and usually an anion to form the second covalent bond.
A. The Sleep Test Optimization Program is prior. authorization initiative for Polysomnography (PSG). There are two types of sleep studies â (1) Attended. Sleep Studies - performed in an outside facility, office, sleep clinic or laboratory; and (2) Unattended.
Two other common kinds of sleep study. Another common test is a split-night study (medical code 95811). It combines a PSG and a continuous positive airway pressure study, or CPAP. The first half of the night is just a basic PSG. If sleep apnea tendencies are exhibited, the patient is woken and is fitted with a mask and hooked up to a CPAP machine.