-
The test, called a carbon isotope ratio test, can distinguish naturally produced from artificial testosterone.
NPR: Landis Facing Uphill Battle on Doping Charges
-
Late Wednesday, his lawyer, Howard Jacobs, acknowledged he'd received a written statement that the carbon isotope test showed the presence of synthetic testosterone.
NPR: Landis Facing Uphill Battle on Doping Charges
-
Hers is not the lab that did the tests on Floyd Landis, but Dr. Ayotte has used the carbon isotope test since the late 1990s.
NPR: Landis Facing Uphill Battle on Doping Charges
-
They've made the allegation, certainly, both to the New York Times and in paperwork provided, that the carbon isotope test was positive, but they don't provide the documents that show that.
NPR: Landis Facing Uphill Battle on Doping Charges
-
The Anthropocene's equivalent of iridium is nitrogen - although there will be other candidates (such as heavy metals, and carbon isotope ratios characteristic of fossil fuel emissions) for geochemists of the far future to identify as the chemical signature of the new epoch's dawn.
BBC: Leaving our mark: Fossils of the future
-
The latest work on sea urchin growth rates uses measures of the isotope carbon-14, which has increased in all living organisms following the atmospheric testing of atomic weapons in the 1950s.
BBC: NEWS | Science/Nature | Red sea urchin 'almost immortal'
-
Unlike archaeological radiocarbon dating based on the fixed rate of decay of the carbon-14 isotope, there is simply no fixed rate of decay of basic vocabulary, which would allow us to date ancestral proto-languages.
BBC: English language 'originated in Turkey'
-
Most of it is an isotope known as carbon-12 (12C), but there is always a smattering of a heavier isotope, 13C, mixed in.
ECONOMIST: Methane and climate change
-
There are many different isotopes of carbon and one that we have probably heard of is in the form of carbon-14, known for radio-carbon dating, but where does this radioactive isotope come from?
FORBES: Climate Scientists Deepening Skepticism of Democracy