I googled it and got both answers, "yes" and "no."
What I mean is: O-H-S, F-H-S, N-H-S, etc.
Ex.'s of "yes": http://www.ncbi.nlm.nih.gov/pubmed/19089987 http://pubs.rsc.org/en/content/articlelanding/2011/ce/c0ce00760a
Ex. of "no": http://www.nature.com/nature/journal/v149/n3773/abs/149218a0.html
What I mean is: O-H-S, F-H-S, N-H-S, etc.
Ex.'s of "yes": http://www.ncbi.nlm.nih.gov/pubmed/19089987 http://pubs.rsc.org/en/content/articlelanding/2011/ce/c0ce00760a
Ex. of "no": http://www.nature.com/nature/journal/v149/n3773/abs/149218a0.html