In\'{e}galit\'{e}s de Harnack et Ph\'{e}nom\`{e}ne de Concentration
  We proove some inequalities concerning the product, sup * inf for some elliptic operators of order 2 and 4. Using those inequalities and the concentration phenomena we can describe the asymptotic behavior of those PDE solutions. 
Samy Skander Bahoura (IMJ)