TV, video games, or Internet: Which activity makes teenagers fat?

I talk a lot about the importance of context in understanding science. The results of one, single research paper do not tell you everything you need to know on a given subject. Instead, you have to look at how those results fit into the big picture. How do they compare to the results of other studies on the same subject? Have the results been independently verified? How do the specific experiments being done influence what you can and cannot say about the results? What questions aren't answered by the study, and what new questions does it bring up?

You should be thinking about that every time you see anybody talk about the results of a single, new study. Without context, you get situations like this one, described by Travis Saunders on the Obesity Panacea blog:

Earlier this year my friend and colleague Valerie Carson published an interesting paper examining the health impact of various types of sedentary behaviour in a sample of 2500 children and adolescents. They created a clustered risk score (CRS) which took into account a child’s waist circumference, blood pressure, cholesterol, and inflammation, and then examined whether it was associated with 3 different measures of sedentary behaviour – accelerometry (an objective measure of movement), self-reported TV watching, and self-reported computer use.

Here is what they found (emphasis mine): For types of sedentary behavior, high TV use, but not high computer use, was a predictor of high CRS after adjustment for MVPA and other confounders. Here is what the Daily Mail had to say: Watching TV most damaging pastime for inactive children, increasing risk of heart disease.

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Scientists: How do ethics and culture shape your work?

Recoding Innovation is a National Science Foundation-funded documentary that's basically about the anthropology of science and engineering.

If you're a scientist or an engineer, you can participate. How does your culture, values, and beliefs make your work happen? The idea here is that ethics aren't something that hold science back. Instead, applying ethics helps scientists and engineers be innovative. It's a cool idea, and I'm looking forward to watching the finished documentary. The video above includes a short example of the kind of stories the editors are looking for.

Submit your story by January 1.

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The trouble with lab mice

You've probably seen this caveat pretty often: Just because a study that uses mice as subjects produces a specific result, doesn't mean you'd get the same result using human subjects. Mice are handy research animals, but they aren't perfect analogues to humans. A mouse study is a stepping stone towards better evidence. It is something we do because there are potentially useful ideas that we should not try out on humans first. But mouse studies should not count as incontrovertible proof of anything.

Usually, when that caveat comes up, the person giving it is talking about fundamental differences between mouse biology and human biology. For instance, a mouse might only need one copy of a genetic factor to grow normally. Meanwhile, a human needs to have both copies or risk altered sexual development.

But there are other problems with mice, problems that have more to do with how we select, breed, and raise mouse models. In a fascinating three-part series on, Daniel Engber looks at how we undermine the usefulness of our own lab mice, and the risks we take when we do so.

If you put a rat on a limited feeding schedule—depriving it of food every other day—and then blocked off one of its cerebral arteries to induce a stroke, its brain damage would be greatly reduced. The same held for mice that had been engineered to develop something like Parkinson's disease: Take away their food, and their brains stayed healthier.

But Mattson wasn't so quick to prescribe his stern feeding schedule to the crowd in Atlanta.

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Faster-than-light neutrino update: What's going on behind the scenes?

The publication process for a research paper about physics works a little differently than other subjects. That's because of arXiv. Funded by Cornell University, this site posts research papers, before they're formally published in a scientific journal. Unlike most scientific journals, which charge big fees for subscriptions or even to view a single paper, arXiv is free and open to the public. You can read everything published there—more than 700,000 papers about physics, math, computer science, and more. The other big difference: arXiv isn't peer reviewed. At least, not ahead of time.

A lot of the time, when you read a newspaper article about a new study in one of those fields, the study hasn't actually yet been published in a peer-reviewed journal. It's just been posted to arXiv, which sort of becomes a crowd-sourced peer review peer review of its own. Especially for headline-grabbing research making big, bold claims.

That's the background you need to understand what's going on right now with the study that claimed to find neutrinos traveling faster than the speed of light. That announcement was made in an arXiv paper. Putting those results on arXiv was as much a way of saying, "Woah, we just found something crazy, please tell us if you see something we've done wrong," as it was a formal declaration of scientific discovery.

Since that paper was published in September, there have been more than 80 follow-up papers, also published on arXiv, offering criticism of the original research or proposing theoretical explanations of how that seemingly crazy finding could fit into physics as we know it. Read the rest

How do we know that the moon isn't cheese?

Sean Carrol explains why there are some ideas science doesn't have to test in order to know that they're ridiculous. (Via Bora Zivkovic.) Read the rest

Space dust: Your tax dollars at work

Your tax dollars build bridges. They pay the salaries of teachers and firefighters. Tax dollars help put people through college, provide a safety net for the elderly and the disabled, and pay for fighter jets and nuclear bombs.

You may not agree all those ways your tax dollars are spent, but they are all, at least, fairly tangible. When it's time for re-election, your senator can point to a roads project, a school, a saintly grandmother, or a missile silo. Through these projects, Americans are being educated, cared for, and protected.

But it's hard to make that clear cost/benefit analysis for basic scientific research. At least, not on a timetable that matches up with election cycles.

Basic research is often weird, and it's often boring. It's the years spent mapping the neurons of zebra fish, so that future scientists can have a more detailed biological model to work with. It's the chemical analysis that has to happen, so that two decades from now somebody else can discover a new cancer-fighting drug. Basic research is about curiosity, and knowledge for knowledge's sake. By it's very nature, basic research relies on public funding. But by it's very nature, it's hard to explain how the public benefits from the basic research we fund.

Attila Kovacs is one of the scientists who put your tax dollars to work. An astrophysicist at the University of Minnesota, he specializes in the study of space dust. That is, yes, dust. In space. It's the sort of thing that would be very easy to mock. Read the rest

Meet Science: How clinical trials work

Did you know that, with a properly conducted series of clinical trials, it can take upwards of 20 years before a medical discovery makes it from the lab to the hospital?

Judy Stone, an infectious disease specialist who does clinical research, has a guest post on the Scientific American blog network today, explaining the basics of clinical trials—where they came from, and how they can go wrong.

She's going to be publishing a series of posts on this topic, and is looking for input on what you want to know about clinical trials. Disclaimer: As a clinical researcher, Stone has a goal here. She'd like to see more people volunteering for clinical research, and part of what she's interested in is the gaps in knowledge that make people wary of participating, or leave them unaware that they can participate. Your input would be helpful.

Image: Pills Phial, a Creative Commons Attribution Share-Alike (2.0) image from luca_volpi's photostream

Clinical trials seek to learn whether a drug (or device) works as expected—it’s unknown, until tested in people. That’s why early phase trials use only a few people, and more are added as experience is gained. Sometimes unexpected discoveries are made along the way. For example, Rogaine was discovered by an astute clinician researcher during a clinical trial studying high blood pressure. The drug, minoxidil, originally under study as an anti-hypertensive medication, was serendipitously found to have the unexpected side effect of stimulating hair growth, prompting a whole new line of products for baldness.

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Caffeine hallucinations: Why "Letters to the Editor" matter in science

Letters to the Editor are an interesting feature of peer-reviewed scientific journals. The function of this section varies from journal to journal, but, in general, this is where you'll find things like critiques of research published in previous issues, and short write-ups on findings that don't yet warrant their own big, formal research paper. Neuroscience blogger Vaughan Bell found a neat example of the latter in an old 1993 issue of the American Journal of Psychiatry.

Dr. Harold W. Koenigsberg and his colleagues were in the process of studying the causes of panic and anxiety disorders, in hopes of better understanding why some people are prone to panic attacks and others aren't. Part of that research involved determining whether you could have a panic attack while sleeping. They wanted to see whether a panic attack could still happen if the patient wasn't actively thinking about the causes of the panic attack, like they might when awake. Basically, Koenigsberg was trying to figure out how much of a panic attack was attributable to chemistry changes, and how much was related to cognitive processing.

Koenigsberg and company injected sleeping patients with caffeine, to produce the physical symptoms of panic. And that's when they noticed something odd. Two of the patients reported olfactory hallucinations—they smelled things that weren't there. Here's what Koenigsberg wrote in his Letter to the Editor:

Mr. A, a 38-year-old man with no personal or family history of psychiatric disorders, received an intravenous dose of 250 mg of caffeine, delivered as a bolus over a 60-second period during an episode of stage 3-4 sleep.

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Meet a paleontologist

What does a scientist do all day? The Smithsonian's Matthew Carrano explains his job as a paleontologist, what he hopes to discover, and why he made a career out of dinosaurs. Read the rest