Your doctor may need to change the doses of your medications or monitor you carefully for side effects. ... Metformin side effects can also affect other parts of the body. It can leave a metallic taste in the mouth, cause heartburn or headache, flushing of the skin, nail changes or muscle pain. More serious metformin side effects include chest pain or rash. ...
Early String Theory. The first attempt to construct a physical model of an atom was made by William Thomson (later elevated to Lord Kelvin) in 1867. The most striking property of the atom was its permanence.
Fifty years ago, in 1964, physicists Murray Gell-Mann at Caltech and George Zweig at CERN came up with the idea of the quark as a response to the bewildering number of elementary particles that were being discovered at the huge atom smasher labs sprouting up all over the world.