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Marcos André via Flickr Creative Commons // CC BY 2.0
Marcos André via Flickr Creative Commons // CC BY 2.0

Scientists Explain How Your Shoes Untie Themselves

Marcos André via Flickr Creative Commons // CC BY 2.0
Marcos André via Flickr Creative Commons // CC BY 2.0

You know you tied your shoelaces properly. You know you did. Yet halfway down the block, you feel your sneaker slipping away from your foot. How could a knot untie itself? Scientists using slow-motion cameras may have figured it out. They published their report in the journal Proceedings of the Royal Academy A.

There are two classic shoelace knots. There’s the “rabbit comes out of the hole, runs around the tree, and returns to his hole” loop-and-pull, and then there’s the crossed-loop bunny ears approach. (Rabbits have apparently cornered the market on shoelace knots.) Both knots are prone to unraveling under strain, although bunny ears are generally considered the more secure option.

Mechanical engineers at Berkeley wondered what was producing the two knots’ different success rates. Their interest, said co-author Christopher Daily-Diamond, goes well beyond untied cross-trainers. “If you can start to understand the shoelace,” he said in a statement, “then you can apply it to other things, like DNA or microstructures, that fail under dynamic forces. This is the first step toward understanding why certain knots are better than others, which no one has really done."

The first step was to catch the knots in the act of coming undone. The researchers trained a high-speed camera on a treadmill, then co-author and runner Christine Gregg put on her sneakers and got moving.

By slowing down the camera and analyzing the physics of Gregg’s footfalls, the research team was able to spot the conspirators tugging away at those poor, unsuspecting knots. The first was the violence of each footfall, as Gregg’s shoes smacked against the treadmill with seven times the force of gravity. This impact stretched and pushed the knot. And while it was weakening, the whipping motion of the bow’s loops and ends simultaneously pulled the strands apart. These two forces combined untied Gregg’s well-formed knots.

"You really need both the impulsive force at the base of the knot and you need the pulling forces of the free ends and the loops," Daily-Diamond said. "You can't seem to get knot failure without both."

The researchers noted that knot failure is not inevitable; often it takes one specific jolt to the laces to start the unraveling clock. “[Your] laces can be fine for a really long time,” Gregg said, “and it's not until you get one little bit of motion to cause loosening that starts this avalanche effect leading to knot failure.”

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Yes, You Can Put Your Christmas Decorations Up Now—and Should, According to Psychologists
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We all know at least one of those people who's already placing an angel on top of his or her Christmas tree while everyone else on the block still has paper ghosts stuck to their windows and a rotting pumpkin on the stoop. Maybe it’s your neighbor; maybe it’s you. Jolliness aside, these early decorators tend to get a bad rap. For some people, the holidays provide more stress than splendor, so the sight of that first plastic reindeer on a neighbor's roof isn't exactly a welcome one.

But according to two psychoanalysts, these eager decorators aren’t eccentric—they’re simply happier. Psychoanalyst Steve McKeown told UNILAD:

“Although there could be a number of symptomatic reasons why someone would want to obsessively put up decorations early, most commonly for nostalgic reasons either to relive the magic or to compensate for past neglect.

In a world full of stress and anxiety people like to associate to things that make them happy and Christmas decorations evoke those strong feelings of the childhood.

Decorations are simply an anchor or pathway to those old childhood magical emotions of excitement. So putting up those Christmas decorations early extend the excitement!”

Amy Morin, another psychoanalyst, linked Christmas decorations with the pleasures of childhood, telling the site: “The holiday season stirs up a sense of nostalgia. Nostalgia helps link people to their personal past and it helps people understand their identity. For many, putting up Christmas decorations early is a way for them to reconnect with their childhoods.”

She also explained that these nostalgic memories can help remind people of spending the holidays with loved ones who have since passed away. As Morin remarked, “Decorating early may help them feel more connected with that individual.”

And that neighbor of yours who has already been decorated since Halloween? Well, according to a study in the Journal of Environmental Psychology, homes that have been warmly decorated for the holidays make the residents appear more “friendly and cohesive” compared to non-decorated homes when observed by strangers. Basically, a little wreath can go a long way.

So if you want to hang those stockings before you’ve digested your Thanksgiving dinner, go ahead. You might just find yourself happier for it.

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Pop Culture
The Princess Ride: Here's What a Princess Bride Theme Park Attraction Might Look Like
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MGM

Do you fight the urge to say “Hello, my name is Inigo Montoya” when introducing yourself? Have you spent the past 30 years mispronouncing the word “marriage”? If so, you may be a diehard fan of The Princess Bride. The cult film (and the book on which it’s based) has inspired board games, merchandise, and countless pop culture references. Now, two theme park designers from Universal have conceived the inconceivable. As Nerdist reports, Jon Plsek and Olivia West have designed the plans for a hypothetical attraction called “The Princess Ride.

Their idea follows the classic river boat ride structure and adds highlights from the movie around each corner. After watching Buttercup and Wesley’s love story unfold, riders are taken past the Cliffs of Insanity, through the Fire Swamp, and into the Pit of Despair. The climax unfolds at Prince Humperdinck’s castle and leads up to the two protagonists riding off into the sunset. The last thing the passengers see is Miracle Max and Valerie waving goodbye saying, “Hope ya had fun stormin’ the castle!”

The ride’s designers make a living turning stories into thrilling attractions. Plsek works as a concept artist for Universal Creative, the group behind Universal’s theme parks, and West works there as a concept writer. While The Princess Ride was just a fun side project for the pair, it isn’t hard to imagine their ride bringing Princess Bride fans to the parks in real life.

For more of Jon Plesk’s concept rides inspired by classics like Dr. Strangelove (1964) and National Lampoon’s Vacation (1983), check out his website.

[h/t Nerdist]

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