Clinical outcome was defined as death in 7 studies [12, 16, 26, 33, 34, 45, 54], intensive care unit (ICU) admission or requirement of mechanical ventilation in 6 studies [8, 10, 15, 17, 21, 23], prolonged viral shredding in 2 studies [43, 44], severe or critical (respiratory distress with respiratory rate 30/min, or oxygen saturation 93% at rest, or oxygenation index 300 mmHg, based on the diagnostic and treatment guideline for SARS-CoV-2 issued by Chinese National Health Committee [55] or the American Thoracic Society guidelines [56] for community acquired pneumonia) in 18 studies, the primary composite end point (ICU admission, the use of mechanical ventilation, or death) in 2 studies [18, 47], abnormal chest imaging in 1 study [52], acute cardiac injury in 1 study [19], progression of disease to more severe status (including increasing oxygen supplement, pneumonia exacerbation, transferred to ICU, and sepsis) in 10 studies [13, 20, 24, 25, 30, 32, 34, 37, 38, 48]

Ammonia is highly polar
The Arizer Solo 2 combines conduction and convection through a ceramic heating element to heat the glass stem chamber
Even minor physical damage can worsen over time, especially with daily use
Additionally, the lens of the eye is particularly sensitive to intense heat, and exposure to high levels of microwaves can cause cataracts