illuminating science

I have a friend who, upon getting the first hints of a cold, goes on a strong diet of zinc, horseradish, garlic, vitamin C, echinacea, and other herbs as appropriate - all obtainable in convenient pill form. As a bit of a skeptic, I’m inclined to believe that a balanced diet will get you most of what you need and that, in general, this is a pretty good scam by the so-called “natural therapy” companies. (I don’t really see why people mistrust drug companies as the Root of All Evil (TM), and yet will happily hand over hundreds of dollars for completely unproven herbal remedies…let alone magnetic therapy!)

However, one particularly interesting herb is echinacea which is supposed to boost your immune system and either protect against the common cold or at least reduce your symptoms. While some people swear by it, I can’t help but attribute it to a combination of placebo effect and selective memory (”Wow, this cold wasn’t anywhere like as bad as my last one. Thanks echinacea!”) Studies have both supported and contradicted its healing powers, and I’ve previously seen lots of bad science on the “support” side. Hence, I’ve been skeptical, and pretty much put it in the money-money-money pile of “natural” remedies, pending further studies.

Cue Dr Craig Coleman, from the University of Conneticut doing a review of 14 earlier studies, involving 1600 people. He found that echinacea typically reduces your odds of catching a cold by 60%, and reduces the length of the colds you do catch by about one and a half days. Now that’s pretty good odds - half as many colds, and only 2-3 days off instead of 3-5! I’ll still maintain a little skepticism because, as Dr Coleman (a pharmacist) points out, for a really clear result, “someone needs to do a really large, well-done, randomised trial. That is unlikely to occur because there is a lack of funding.” Why? No-one can patent echinacea, so no-one will front up the money for a study like that! (Particuarly not if it turns out to do better than commercial meds! But that’s veering towards conspiracy theories…)

Interestingly, though, there’s a flip side - if echinacea really does stimulate the immune system, it could be harmful to people who already have overactive immune systems. People with autoimmune diseases, where the immune system attacks healthy cells, actually take immunosupressants which reduces the immune response. Dr Coleman also points out that although there are no harmful effects observed so far, there hasn’t been any long terms studies. Just because it’s natural, doesn’t mean it’s safe! (Hemlock, anyone? And again, people demand long term studies for drugs which might save their lives, but if a herb can stave off the cold then full steam ahead. I don’t get it.) Whether one should be taking it as a preventative then? In general, you want to do as little to your body as you can, I think, so I guess there’s a trade off there - unknown risks, vs cold prevention.

Either way, I am probably now swayed enough to purchase some echinacea, just for when I get a sniffle. Even if it shouldn’t, perhaps I’m now convinced enough for the placebo effect to kick in!

Just a quick note that I’m about to upgrade…so if things are offline, you’ll know why!

And we’re done, nice and painless.

Here’s a neat conceptual problem that I first puzzled over in first year, and encountered again doing a bit of tutoring recently. I like it, because it forces you to think about the assumptions and connections between a couple of different things. This is probably only really interesting if you’ve done high school physics, though you really just need to know (and understand) three things:

1. That gravitational potential energy is given by E = mgh
2. The concept of work, basically being the energy added to or removed from a system (usually, by mechanical means)
3. That the work done on an object is given by W = Fs, that is, the work is the net force on an object multiplied by the distance (displacement) over which that force acted.

So, if I push a smooth block along some ice with a force of 10 Newtons, over a distance 5 metres, it gains 50 Joules of energy from my 50 Joules of work. If the ice is flat, this will be kinetic energy, and you can calculate its resulting speed the usual way.

Now, let’s say I’m holding a mass on my palm. I raise it up very slowly from my waist to my head, starting and ending at rest. What is the work done on the object? Well, if we neglect the initial and final accelerations (I said “very slowly”, so these are small) the block will move with a constant speed all the way up. Hence, there’s no net force, and the work done is zero. But, it now has more gravitational potential energy, because it’s higher up - despite there being no net external force to give it any energy. It seems we’ve created energy from nothing.

What, if any, is the flaw in my reasoning?

So for my first post for ages, I’m going to link direct to someone else’s post - a great review of the brand new publication International Journal of Creation Research. I quote from 6_bleen_7’s post:

But there is something more sinister at work here, and it all hinges on one hyphenated word in the description of this farcical publication: “IJCR is a professional peer-reviewed journal of interdisciplinary scientific research that presents evidence for recent creation within a biblical framework”.

It’s a really good post, definitely worth reading, and shows just how far the creationism movement is going to undermine the scientific method. In this case, it’s the attack on “peer review” - the idea that most scientific publications are subjected to review and argument by other scientists, with knowledge of your area, before seeing the light of day. This means that, reading the article, you can be fairly sure that it adheres to a minimum standard of scientific quality. It might be wrong, but not by intent or through stupid mistakes.

So, for instance, despite many claims of the power of biomagnetic healing, there are no peer reviewed papers showing any health benefits of permanent magnets. Simiarly, there are no peer reviewed papers showing any “evidence” for creationism, or even providing good interpretions for fossils, carbon dating, etc. That’s not because no science journals will publish creationist ideas - it’s because there’s no evidence for them.

So, what else would you do, but start your own “peer reviewed” journal and publish all of your supposed theories in that? Then you’re just as legitimate as any scientist.

The solution is too complicated, unfortunately, and that’s the idea of impact factor - the journal world equivalent of Google’s PageRank technology. Journals are rated according to how often their articles are cited by other articles (the equivalent of web links). And this is a pretty simple picture. One could imagine that Google’s Google Scholar would use a more sophisticated version, weighting each article’s contribution by how much it is cited - just like Google does with regular web searches. I expect you’d find that such algorithms would give pretty poor weighting to a journal never cited by anything but itself. (Of course, people would have to resist the urge to write things like “The ridiculous article by Smith (2007) says that…”)

But, how do you explain all that to a newspaper reporter, tossing up the scientific merits of evolution vs creationism?