Pneumatic tube systems — little canisters shot through a series of tubes via the power of compressed air — have been around since the 19th century when they were briefly popular as a way to quickly deliver mail in big cities. Today, they're probably most familiar from their use in drive-through banking, but the tubes also turn up at libraries (the one at the main branch of the New York Public Library is particularly steampunky), in scientific laboratories, and in hospitals.
Last month, I spent an inordinate amount of time in one Minneapolis area hospital, waiting for an induced labor to kick in. How do you entertain yourself between the insertion of the IV line and the beginning of serious contractions? Turns out, you go on a lot of short walks, you watch some TV, and (if you're lucky) you convince the nurses to let your husband "mail" his cell phone from the labor/delivery department to the post-natal department, using the hospital's pneumatic tube system.
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I'm loving the "Doing Stuff with Crazy Aunt Lindsey" series of hands-on science YouTube videos for kids. I can't find the host's full name on the YouTube page or her website, but she's a fantastic presence and so are the kids that appear with her. The result is a series of videos that are adorable, high-spirited, creative, and fun—full of great, simple projects that pack a surprising amount of science "oomph" behind them.
GE hosted a contest to make super-short science videos for Vine and the results feature some really clever, nifty little clips.
For hand towels, astronauts get those little vacuum-packed pucks that you kind of have to unravel into a towel. But what happens when you actually put the towels to use?
Two Nova Scotia high school students, Kendra Lemke and Meredith Faulkner, submitted this experiment to Canadian Space Agency and got to see astronaut Chris Hadfield actually test it out on the ISS. The results are seriously extraordinary and you need to see them.
It seems like a weird past-time, magnetizing ants, but it has some practical purposes. At his blog, media engineer Andrew Quitmeyer explains how he mixed magnetic powder into insect-safe enamel paint, and what he was able to do with it.
The big benefit to something like this is that it could allow scientists to easily alter the populations of social insect groups. Each colony of ants functions, in many ways, like a single organism. So what happens to that hive mind if you remove all the ants doing one particular type of task? Instead of painstakingly picking out each worker with a pair of tweezers every time you want to try this, you could create a colony in which all the workers have had magnetic paint daubed onto their abdomens. Then, you could quickly and easily collect some of them, or all of them, using a magnet. Hunting ants with a tweezer once > hunting ants with a tweezer over and over and over.
Another, possibly less legitimate, use of the paint is demonstrated by Quitmeyer in this video. (Quitmeyer, for the record, is not a social insects researcher.) Using single painted ants in a population of unpainted ants, he plays around with the way colonies remove unhealthy members of their own community. When a magnetized ant starts flopping around erratically in response to a nearby magnet, nearby ants quickly react.
As Quitmeyer says in the video, this demonstration quickly passes from science into mad science (or, at least, YouTube science).
Thanks to Leah Shaffer!
The Joule Thief is a way of producing enough electricity to run small, but useful, electric lights using cast-off trash like pop-can tabs and "dead" batteries. It's especially handy in the Himalayas, writes inventor and Google Science Fair judge T.H. Culhane. There, electricity is a precious resource. But the components needed to build a Joule Thief are abundant, thanks to climbers and tourists who leave behind all sorts of surprisingly useful litter.
Last week, Culhane joined a G+ hangout sponsored by National Geographic and Girlstart to talk about the value in things we throw away and walk viewers through the construction of their very own Joule Thief. You can watched the video of the event, or read the instructions for building a Joule Thief at Culhane's blog.
The fact that the Joule thief allows one to run a 3V LED from a 1.5 or 1.2 Volt battery would itself be astounding, because it means you only need half the number of batteries to get the same light.
Some of you are thinking "wait, maybe it enables you to use a single 1.5 volt battery to light a 3V LED instead of the usual two, but doesn't it just make that battery last half as long? Great question, but the answer is that the Joule Thief, which works by building up and collapsing a magnetic field around the torus (which acts as an electromagnetic inductor) actually is more efficient than using a battery directly because it PULSES the energy to the LED. You see the lightbulb shining brightly, but in fact it is turning on and off very rapidly as the magnetic field of the inductor builds up and discharges again and again. That means that though the light appears to be on all the time it is actually turning on and off and saving energy because it isn't on all the time.
It turns out that the Joule Thief enables the battery to keep supplying electrons to the light long after the battery is normally considered DEAD. So the battery actually lasts much much longer than a normal battery. I've observed "dead" batteries working down to about 0.5 Volts. Normally a 1.5 V battery is considered dead when it reaches 1.0 volts. But the Joule Thief can "steal" the remaining energy much below that. And that got me thinking -- could I use other sources of between 0.5 and 1.0 Volts to run a 3V LED?
T.H. Culhane's post on The Joule Thief (includes instructions for making a Joule Thief with batteries and alternative electricity sources)
Is coffee bad for you or good for you? Does acupuncture actually work, or does it produce a placebo effect? Do kids with autism have different microbes living in their intestines, or are their gut flora largely the same as neurotypical children? These are all good examples of topics that have produced wildly conflicting results from one study to another. (Side-note: This is why knowing what a single study says about something doesn't actually tell you much. And, frankly, when you have a lot of conflicting results on anything, it's really easy for somebody to pick the five that support a given hypothesis and not tell you about the 10 that don't.)
But why do conflicting results happen? One big factor is experimental design. Turns out, there's more than one way to study the same thing. How you set up an experiment can have a big effect on the outcome. And if lots of people are using different experimental designs, it becomes difficult to accurately compare their results. At the Wonderland blog, Emily Anthes has an excellent piece about this problem, using the aforementioned research on gut flora in kids with autism as an example.
For instance, in studies of autism and microbes, investigators must decide what kind of control group they want to use. Some scientists have chosen to compare the guts of autistic kids to those of their neurotypical siblings while others have used unrelated children as controls. This choice of control group can influence the strength of the effect that researchers find–or whether they find one at all.
Scientists also know that antibiotics can have profound and long-lasting effects on our microbiomes, so they agree on the need to exclude children from these studies who have taken antibiotics recently. But what’s recently? Within the last week? Month? Three months? Each investigator has to make his or her own call when designing a study.
Then there’s the matter of how researchers collect their bacterial samples. Are they studying fecal samples? Or taking samples from inside the intestines themselves? The bacterial communities may differ in samples taken from different places.