Once the acute attack subsides, levels of uric acid can be lowered via lifestyle changes and in those with frequent attacks, allopurinol or probenecid provides long-term prevention.Gout affects about 1 to 2% of the Western population at some point in their lives. This is believed to be due to increasing risk factors in the population, such as metabolic syndrome, longer life expectancy and changes in diet. Long-standing elevated uric acid levels (hyperuricemia) may result in other symptoms, including hard, painless deposits of uric acid crystals known as tophi.Gout is due to elevated levels of uric acid in the blood.This occurs due to a combination of diet and genetic factors.Most excited electrons will soon recombine with lattice ions, but some will be trapped, storing part of the energy of the radiation in the form of trapped electric charge (Figure 1).
The crystallization of uric acid, often related to relatively high levels in the blood, is the underlying cause of gout.
OSL works because all sediments have some natural radioactivity, caused by the presence of uranium, thorium and potassium isotopes in heavy minerals such as zircons.
We analyse the quartz or feldspar minerals in sand deposits.
This page was contributed by Dr Georgina King from the Aberystwyth Luminescence Research Laboratory in the Institute for Geography and Earth Sciences. OSL is used on glacial landforms that contain sand, such as sandur or sediments in glacial streams.
| Calculating Age | Challenges for OSL | Case studies of OSL dating in glacial environments | References | Comments | Another way of dating glacial landforms is optically stimulated luminescence dating (OSL).