The absorber rod comprises cladding of stainless steel closed by plugs and containing a column of absorber pellets e. The inert nano-sized particles may comprise metal oxides, metal nitrides, metal carbides, metal borides, etc. A specified branch and elements hanging therefrom can be highlighted when displayed, such that differences in the manner in which individual elements of the overlapped dendrograms are clustered can be easily recognized. An output from the second buffer switches a supply select to selectively pass the higher supply voltage or a reduced supply voltage to the first buffer.