Proteins were identified by mass spectrometry (Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland) and by N-terminal sequencing using the Edman degradation method (Biocentrum; Kraków, Poland).
Stained protein bands were excised from the gel and analyzed by liquid chromatography coupled to mass spectrometer in the Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.
The protein bands were numbered 1 to 6, excised from the gel stained with silver [ 20] and sent for identification by mass spectrometry (LC-ESI-MS/MS) at the Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences IBB PANN) in Warsaw, Poland.
Radiocarbon measurement (C) dates the lowest layer of occupation to around 3980 ± 40 BP (personal communications; calibrated and measured by Wu Xiaohong, Head of the Laboratory of Accelerator Mass Spectrometry, Peking University), which is older than that of the Gumugou cemetery (dated to 3800).
MS analysis was performed by LC MS in the Laboratory of Mass Spectrometry (IBB PAS, Warsaw) using a nanoAcquity UPLC system (Waters) coupled to an LTQ-Orbitrap Velos mass spectrometer (ThermoScientific) as previously described (37), and the data were analysed as detailed in Supplementary Experimental Procedures.
Red and blue arrows indicate the pre-collision velocity vectors of the NO and Ne beams in the laboratory and center-of-mass frames of reference, respectively.
The pre-collision laboratory (red) and center-of-mass (blue) velocity vectors of the NO and Ne beams, as well as the center-of-mass velocity vector (green) are indicated.
The final velocities of the scattered NO radicals in the laboratory frame were then calculated from a coordinate transformation between the center-of-mass and laboratory frames.
Many laboratories have little experience of mass spectrometry.
Although these steps are now performed manually, and mass spectrometers are not yet widely distributed in clinical laboratories, the increasing popularity of mass spectrometry in biomedical sciences and the advent of smaller, lower-cost instruments could facilitate wider use and integrated instrumentation.
