  All the components of cosmic rays have 'structure' in their energy spectra at
some level, ie deviations from a simple power law, and their examination is
relevant to the origin of the particles. Emphasis, here, is placed on the
large-scale structures in the spectra of nuclei (the 'knee' at about 3 PeV),
that of electrons and positrons (a shallow 'upturn' at about 100 GeV) and the
positron to electron plus positron ratio (an upturn starting at about 5 GeV).
  Fine structure is defined as deviations from the smooth spectra which already
allow for the large-scale structure. Search for the fine structure has been
performed in the precise data on positron to electron plus positron ratio
measured by the AMS-02 experiment. Although no fine structure is indicated, it
could in fact be present at the few percent level.
