City Slalom

Monday's I Can't Believe It's Science discussed a few recent "science-ish" articles including one by Richard Wiseman, a University of Hertfordshire psychologist, that found world-wide walking speeds have increased since the last such study in 1997.

I have no trouble believing that in our increasingly 24/7 society, where we're multitasking and trying to be in 3 places at once ,we've picked up the pace and are getting there faster than we did just 10 years ago. After all, 10 years ago, cell phones were big clunky things, blackberries were fruit that you ate and email was only good for sending around unix-based lewd jokes, or that 's what it was used for at my college at least... I feel so old.

The part of the article that surprised me was that New York City was only the 6th fastest city in the world. Working in midtown I think that we're fairly fast walkers, especially in the Rockefeller Concourse... if you're not careful you'll get flattened by some snooty-looking ad executive wearing 4 inch heels and through some miracle of biomechanics power walking to get to where ever ad executives have to go.

So although I was first surprised that Singapore (really? Singapore? Maybe they really are an Asian Tiger force to be reckoned with like The Economist says... those fast walking Singhs) had garnered first place, I soon recalled that not all those who walk in New York are (a) New Yorkers and (b) fast walkers.

To address these annoyingly slow walkers, Time Out New York, the obsessive guide to compulsive entertainment, took matters into their own hands. Dressing up like oversexed meter maids, they handed out tickets to individuals guilty of the following infractions:

• Walking too slowly in a crowded area
• Stopping in an inconvenient place
• Blocking pedestrian traffic by walking side by side in a group of three or more
• Irritating use of cell phone
• Stopping at the top of the stairs in a subway station (Great quote from the article: "Where is Wooster? Hint: not at the top of the stairs")
• Other (I think this category could be extended to the tourists who sling their H&M bags willy-nilly and who are generally recipients of the evil sidewalk eye*)

It seems clear to me that in order to be contenders for 2017's award for fastest walking city, New Yorkers are going to have to get serious about enforcement of the afore mentioned moving (or failure to move) violations. You can download your own spiffy citations like the one pictured at the link above. So get out there and show those annoying foot draggers that we won't stand for their leisurely strolls down 5th Avenue, or any other avenue!

*see evil subway eye

Better Drinking through Science

Now this is the kind of science we should be supporting more of! According to Seed Magazine, Robert MacPherson, a mathematician at the Institute for Advanced Study in Princeton, New Jersey, and David Srolovitz, a physicist at Yeshiva University, New York have discovered why some beers holds their head and others do not.

Surprisingly, the degree to which a beer holds its head is not directly correlated to the blood alcohol content of the beer's dispenser, as I had always suspected. But, according to Seed Magazine:

"Beer foam is a microstructure with complex interfaces. In other words: a cellular structure comprising networks of gas-filled bubbles separated by liquid.

The walls of these bubbles move as a result of surface tension—and the speed at which they move is related to the curvature of the bubbles. As a result of this movement, the bubbles merge and the structure coarsens,” meaning that the foam settles and eventually disappears."

Ostensibly, the difference in Lager and Stout, aside from the obvious differences in taste, lies in variations created either by the liquid surrounding the bubbles or by the gas filling the bubbles. My money's on the gas since I know (from meticulous pub-based research) that Guinness taps require a nitrogen source and other beer taps just require regular carbon dioxide.

On a related note, just to show you the difference between Nature, where MacPherson and Srolovitz's work was published yesterday and Seed Magazine where I just read about their paper, I saw the citation below on my weekly email table of contents from Nature and thought, "Yawn, who cares about von Neuman relations and microstructures." Of course I failed to read the last line in the summary. Contrast that with Seed's catchy headline, "Head Start: Scientists Crack Beer-Froth Enigma," all I can say is "thank God for science writers, Nature should consider hiring some!"

To recap:

Guiness and Budweiser are inherently different

Boring:

"The von Neumann relation generalized to coarsening of three-dimensional microstructures"
(Nature Volume 446 Number 7139 p1053)

Over 50 years ago, von Neumann derived an exact formula for the growth rate of a cell in a two-dimensional cellular structure. Now the extension of this result into three (and higher) dimensions has been found. The formula could lead to predictive models for various industrial and commercial processing scenarios, such as controlling the head on a pint of beer.
Robert D. MacPherson and David J. Srolovitz

Cool: