Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Safety margins for (A) the thumb and (B) the virtual finger: group averages and standard errors (bars). The solid line represents the thumb at high-friction contact (HFC), and the dotted line represents the thumb at low-friction contact (LFC).
