Leaving the Simpson Desert

Steve Simpson

Steve Simpson was born and grew up in Australia. After completing his undergraduate degree at the University of Queensland, he travelled to London where he undertook his PhD on locust feeding physiology. Steve then spent 22 years in Oxford, fi rst in Experimental Psychology and then in the Department of Zoology and the Natural History Museum, before being enticed back to Australia in 2005. Toge...

On the Deligne-Simpson problem

The Deligne-Simpson problem is formulated like this: give necessary and sufficient conditions for the choice of the conjugacy classes Cj ⊂ SL(n,C) or cj ⊂ sl(n,C) so that there exist irreducible (p + 1)-tuples of matrices Mj ∈ Cj or Aj ∈ cj satisfying the equality M1 . . .Mp+1 = I or A1 + . . .+Ap+1 = 0. We solve the problem for generic eigenvalues with the exception of the case of matrices Mj ...

Leaving the Past Behind

There is considerable interest from the wider scientific community in the heritability of epigenetic states across generations, and this has arisen as a result of a series of studies in mice [1,2], flies [3], plants [4,5], and yeast [6] over the past decade. These studies have identified genetic elements at which epigenetic states appear to be inherited through meiosis. The Lamarckian implicati...

Leaving the sheltered workshop

Leaving the Banquet

The offerings in this, my last issue as Editor of Addiction Science & Clinical Practice, reinforce my feeling of stepping away from a banquet that has many rich courses still to come. In this final issue produced by NIDA: • Drs. Manoranjan D’Souza and Athina Markou review what researchers have discovered about how nicotine affects brain function to produce dependence, and examine the prospects ...