The pathogenesis of ectopic gastric mucosa is a matter of debate between a congenital-embryological-and an acquired origin-consecutive to a gastroesophageal reflux (GER) like Barrett's esophagus -, the most commonly accepted theory being that these areas are embryological remnants.
Standard size latex filled helium balloons stay afloat for approx 8 - 12 hours, metallic helium filled balloons float for 2-5 days. I have found that a 36 latex helium filled balloon can stay afloat for a number of days due to the thickness of the balloon and the massive quantity of helium.
How long does a portable oxygen tank last? Oxygen tanks can last between 0.75 and 37.5 hours. How long they last depends on the size of the tank, the pressure in the tank and the flow of oxygen, which ranges from 0.5 to 5 liters per minute. For example, a D-size tank that is full last only 1.25 hours at 4 liters per minute but can last 10 hours at 0.5 liters per minute.