Scalable distributed processing of mass spectral difference networks

摘要

Mass spectrometry (MS) is an analytical technique to filter, detect, identity and/or me as ure compounds by the mass-to-charge ratios ofions formed from the compounds. The quantity of mass-to-charge ratio is commonly denoted by the symbol "m/z" in which "m" is ionic mass in units of Daltons and "z" is ionic charge in units of elementary charge, c. Thus, mass-to-charge ratios arc appropriately measured in units of "Da/e". Mass spectrometry techniques generally include (1) ionization of compounds and optional fragmentation of the resulting ions so as to form fragment tons; and (2) detection and analysis of the mass-to-charge ratios of the ions and/or fragment tons and calculation of corresponding ionic masses. The compound may be ionized and detected by any suitable means. A "mass spectrometer" generally includes an ionizer and an ion detector. Combining mass spectrometry with chromatography provides an extremely useful technique for detection, identification and (or) quantification of components of mixtures or of analytes within mixtures. This technique generally provides data in the form of a mass chromatogram, in which detected ion intensity (a measure of the number of detected ions) as measured by a mass spectrometer is given as a function of lime. Various separated chemical constituents can elate from a chromatographic column as a function of time. As these coaslituents come off the column, they are submitted for mass analysis by a mass spectrometer. The mass spectrometer accordingly generates, in real time, detected relative ion abundance data for ions produced from each cluting analyte, in turn. Thus, such data is inherently three-dimensional, comprising the two independent variables of time and mass (more specifically, a mass-related variable, such as mass-to-charge ratio) and a measured dependent variable relating to ton abundance.