{id_rubrique != 12}: returns the data from sections with an (#ID_RUBRIQUE) ID that is not equal to 12.
{titre !== ^(a|e|i|o|u|y)}: returns data from the objects (articles, sections...) which have a (#TITRE) title that does not start with a vowel (irrespective of uppercase or lowercase characters).
{extension !IN gif, jpg, png}: returns the data for the documents that have an extension which is not any one of gif, jpg or png.
See also
Other logical operator
Conditional criteria
Operators