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Greetings from Skid Row Chopper Fest 2015

#harley #harleydavidson #Panhead #Shovelhead #knucklehead #blockhead #Ironhead #evo #sportster #chopper #chopcult #gpoy #losangeles #california (at Black Board Cafe)

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Scientists at the University of Alberta filmed a knuckle cracking in an MRI scanner to find out what makes that popping sound. I’ve wondered about this for ages, and I can’t believe this hasn’t been done before!

Turns out, contrary to the dominant theory of the past 50 years, the pop happens when a bubble forms between the two bones - not when that bubble collapses. Even better, some think that knuckle-popping might actually be good for your joints. Well, well, well, looks like my sister was wrong! 

More from NPR’s Rob Stein.