Prove (to show the truth): prove > proved > proved
Aside from specific legal uses (e.g., innocent until proven guilty) the variant past participle, proven, has never been preferred and should be avoided.
Prove suggests unquestionable, absolute certainty. While a common term in mathematics, prove should have no home in scientific writing. Experiments and studies do not prove, they show, they demonstrate, and they suggest. No matter how infallible a study or its design, it is still subject to scrutiny, skepticism, and reproduction. Prove, thus, is not a scientific word, though it has found an unfortunate misuse in journalistic and scientific writing, usually to the detriment of a scientifically-untrained public. Be not the poor scientist who thinks studies and experiments prove anything; be not the lazy journalist who misplaces a scientifically-written result with the absolute, unquestionable certainty of the word prove.