Most rare diseases are genetic, and thus are present throughout the person's entire life, even if symptoms do not immediately appear. Many rare diseases appear early in life, and about 30 percent of children with rare diseases will die before reaching their fifth birthday. With a single diagnosed patient only, ribose-5-phosphate isomerase deficiency is considered the rarest genetic disease.
When the temperature in the core reaches about 100 million degrees, the helium will begin to fuse into carbon by a reaction known as the triple-alpha process, because it converts three helium nuclei into one carbon atom.This generates a great deal of heat.n heavier stars, the oxygen can in turn fuse with the helium to make neon.) Helium fusion produces only 9% as much energy per kilogram as hydrogen fusion, so energy-wise, the Sun continues to be mainly a hydrogen reactor. 90% of its luminosity still comes from burning hydrogen.
All stars live by fusing hydrogen into helium. In the first step of the process, two hydrogen atoms fuse to form deuterium. In the next step, another hydrogen atom fuses with the deuterium, creating a rare isotope of helium that has two protons and one neutron in its nucleus. In the third step, two of the rare helium atoms fuse to create a single normal helium atom and two hydrogen atoms. The fusion pathway described above requires six hydrogen atoms to create one helium atomâhowever, there are two hydrogen atoms left over at the end of the process. The net result is that it takes four hydrogen atoms to make one helium atom.