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.
Polysomnography monitors your sleep stages and cycles to identify if or when your sleep patterns are disrupted and why. The normal process of falling asleep begins with a sleep stage called non-rapid eye movement (NREM) sleep. During this stage, your brain waves, as recorded by electroencephalography (EEG), slow down considerably. Your eyes don't move back and forth rapidly during NREM, in contrast to later stages of sleep. After an hour or two of NREM sleep, your brain activity picks up again, and rapid eye movement (REM) sleep begins. Most dreaming occurs during REM sleep. You normally go through four to six sleep cycles a night, cycling between NREM and REM sleep in about 90 minutes.