1, 2 It contains all normal layers of the intestinal wall and, in approximately 50 percent of cases, contains tissue from other sites (ectopic tissue). 2 This ectopic, or heterotopic, tissue can often be the cause of complications occurring in Meckel's diverticulum. Meckel's diverticulum occurs in about 2 percent of the population, making it the most prevalent congenital abnormality of the gastrointestinal tract.
A common helium-filled latex balloon lasts from about 12 hours up to two days. However, the size, type of material, and presence of a sealant all affect the balloon's lifespan. The treatment and level of activity to which the balloon is subjected also affects how long it floats.
By dividing this flux into the column density of helium in the atmosphere (1.1 x 1020 cm-2)we obtain a residence time for helium of 2 million years, much less than the characteristic escape time. âThis result implies that the rate of Jeans escape at 1500 K is much smaller than the crustal source of helium.