Success rates of long-term weight loss maintenance with lifestyle changes are low, ranging from 2 to 20%. Dietary and lifestyle changes are effective in limiting excessive weight gain in pregnancy and improve outcomes for both the mother and the child.eight loss with these drugs is modest. Over the longer term, average weight loss on orlistat is 2.9 kg (6.4 lb), sibutramine is 4.2 kg (9.3 lb) and rimonabant is 4.7 kg (10.4 lb).
Part of the Computing fundamentals glossary: In science, a half-life (also, as a noun, spelled half life) is the amount of time it takes for half of a substance or entity to undergo some specified process.
Not all of the atoms of a radioisotope decay at the same time, but they decay at a rate that is characteristic to the isotope. The rate of decay is a fixed rate called a half-life. The half-life of a radioisotope describes how long it takes for half of the atoms in a given mass to decay.Some isotopes decay very rapidly and, therefore, have a high specific activity. Others decay at a much slower rate.he rate of decay is a fixed rate called a half-life. The half-life of a radioisotope describes how long it takes for half of the atoms in a given mass to decay. Some isotopes decay very rapidly and, therefore, have a high specific activity.