<s>
*	O
hierarchy	O
is	O
a	O
major	O
class	O
of	O
newsgroups	B-Application
in	O
Usenet	B-Application
,	O
containing	O
all	O
newsgroups	B-Application
whose	O
name	O
begins	O
with	O
"	O
sci	O
.	O
</s>
