Influence of zonal flows on unstable drift modes in ETG turbulence
  The linear instability of the electron temperature gradient (ETG) driven modes in the presence of zonal flows is investigated. Random and deterministic $cos$ - like profiles of the zonal flow are considered. It is shown that the presence of shearing by zonal flows can stabilize the linear instability of ETG drift modes. 
V. M. Lashkin, Yu. A. Zaliznyak, and A. I. Yakimenko