Complex sentence: In 2016, stress granule "cores" were experimentally identified and then biochemically purified for the first time and proteins in the cores were identified in an unbiased manner using mass spectroscopy.
Split into simpler sentences: In 2016, stress granule "cores" were experimentally identified and then biochemically purified for the first time. Proteins in the cores were identified in an unbiased manner using mass spectroscopy.