registered trademark insignia

[Paul N Hengen]

I was writing a paper that included the brand names of some materials and
couldn't figure out what the difference between trademark [TM] and registered
trademark [circled R] is. Please tell me. What happens if I use the wrong one
in a publication?

*******************************************************************************
* Paul N. Hengen, Ph.D.                           /--------------------------/*
* National Cancer Institute                       |Internet: pnh at ncifcrf.gov |*
* Laboratory of Mathematical Biology              |   Phone: (301) 846-5581  |*
* Frederick Cancer Research and Development Center|     FAX: (301) 846-5598  |*
* Frederick, Maryland 21702-1201 USA              /--------------------------/*
* - - -  Methods FAQ list -> http://www.ncifcrf.gov:2001/~pnh/info.html - - - *
*******************************************************************************