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.
Save. Balloons take only a moment to fill when using a helium tank, but figuring out how to tie these party decorations to secure them -- and not let the helium escape -- may present more of a problem. Professional decorators and balloon artists have developed tying techniques that save both time and effort.