As for our divergent tastes in music… I bet you’ll like this one.

The questions I’m posing here are:
1-Can modern bycicle helmet actually help your head in a crash and to what point?
2-Are typical crash conditions which involve your head within the design bounds of bicycle helmets or do they occur at a point where it would make no difference?

Just trying to clarify the scope of what I’m discussing here. It also seems like the documents you suggested in your comment deal with that point.

http://www.cpsc.gov/LIBRARY/FOIA/FOIA98/PUBCOM/34C7A89B.PDF

Basically, engineer Sundahi argues against the use of a heavier test mass (5kg was proposed for the standard instead of about 3kg) for infant helmets. The justification is that helmets need to decelerate the head at impact respecting a certain maximum acceleration. To do so, the helmet crushes. (Sundahi says that energy absorption is not the critical factor, but acceleration/time is the critical parameter to watch. While it may be through, most materials used to decelerate impacts do so via crushing which absorbs impact energy, so really the helmet does both, it decelarates the head and absorbs energy as crushed materials don’t tend to rebound very hard, but nonetheless, that’s not the point.) The analysis engineer Sundahi goes through shows that a helmet designed with a 5kg test mass would end up being stiffer (the liner material is made more dense) and a lighter head would not allow the liner to crush, but really just to rebound. So the helmet would decelarate the head, but make it reaccelarate the other way. The analysis also shows such a helmet in such a condition would also produce more acceleration than it was designed for.

It’s quite interesting, but this letter doesn’t tell me whether this has caused actual head trauma in children wearing helmets designed for heavier heads. Also, this document is from 1998. I haven’t looked but is the standard still at 5kg for infant head proxy?

I’m not saying the Sundahi letter is useless, I’m just wondering if there’s more information on this particular issue. From the analysis in there, it sounds like something to be investigated further. Could it be that in the end, maximum acceleration isn’t the critical factor in head damage in children? This is an interesting discussion (and I think an important one).

I haven’t read the second document you sent, but let me do so today and comment back here.

Matt Hanson

I really like onlike puzzles. A recent one that I found and really enjoyed was a Toyota IQ challenge. Kind of funny that Toyota created a puzzle, but it has nothing to do with Toyota, but the puzzle is actually quite simple and fun. Try to unlock the cube:

http://www.toyota-europe.com/innovation/design/concept_cars/intelligence/en/index.aspx

The PLOS is a great initiative. As I said above, the basic idea of how we WANT to communicate science is fine. How we IMPLEMENT it today is something else. I’m not all that familiar with PLOS, but my understanding is that it’s open (free) access and the rights are kept with the publishing scientist(s). PLOS does have limitations.

1- it charges the authors for publishing their article. At the core, I have nothing against it. Someone has to pay for it. From the looks of their webpage, it seems quite a hefty fee. They do have fee waivers if you don’t have funds, so this is probably one of the reasons why the fee is so high. The people that get waivers have to be offset by the paying users. I’ve had argued to me by a journal editor (a good type, I quite enjoyed discussing with him when I had access to him) that there were only 2 business models available. “Either the person who reads pays or the person who publishes pays. In the end, someone has to pay the fee.” (I’m paraphrasing, this was over a year ago, I don’t remember the exact words.) I don’t agree with that statement. First, we should make the system almost completely an online one. This brings the publishing costs to a bare minimum. (There are still costs associated with moving bits of information instead of stacks of glossy paper, but it’s much lower. Plus it’s more ecological, presumably.) The only piece of information I would distribute on paper form, and only if it is requested, is a digest of the new articles on the site or a summary of the ones that may interest you. I’d much rather send that information via e-mail though. Second, I’d offset the remaining costs with advertising. Yes, I said it, advertising. People don’t like advertising, yet we put up with it even as scientist in large distribution scientific publications. Think “Physics Today”, etc. I believe that advertising well done can be a benefit for the user. Think “Amazon”. Seriously. Anyone’s who’s looked at more than 5 products (not even bought them) on Amazon knows exactly what I’m talking about. You can’t lie and claim that the “Here’s a product you might like” section isn’t always spot on. Unobstrusive, well-targeted, thoughtful and visually appealing advertising can be a added value for the user and a revenue stream for the maintainer of the system. Yes, I said it, I’m sorry. Advertising-supported, (not necessarily) peer-reviewed, scientific publication. Hate me if you will, I think it has potential.

2- PLOS is limited to biology/genetics/medicine. I guess I should call it Health Sciences. This isn’t really a bad thing. It’s a business decision. At the beginning, Facebook was only meant as a platform for university students. Maybe PLOS will expand, I don’t know. I’d like it if it did, though.

3- (And probably the only real criticism:) PLOS is limited to conventional expressions of scientific results. By this I mean that what you get from PLOS is a collection of bar graphs, texts and fixed graphics. To be fair, this is not only the state of just about every single scientific publication today, but PLOS is also showing signs of improvements. There’s this new thing, called a “SciVee”. I think it’s at http://www.scivee.tv. I’m not a huge fan. Basically the idea is that once your paper is published, you can go and make a video explaining your paper. Then, you attach the video to the paper on the site. It’s an improvement. It’s a step. Not a leap, not a bound and not a revolution. It’s a step in the right direction. Ultimately, I think the format of scientific expressions has to explode. The only reason why we’ve used bar graphs, text and static images is because, until now, that’s the only thing we knew how to publish. Those were the limitations of the medium. Well not anymore. By making the papers directly available online, there’s nothing stopping you from attaching executable code to your paper (hopefully, nobody puts viruses there). Maybe some people would want to attach source code. I can’t count the number of instances where I read a paper titled “A new algorithm for…” with no reference to a webpage with an actual nuts&bolts implementation of that algorithm in a language. An algorithm in mathematical form is necessary, an implementation in a known computer language is useful. Why not attach movies? High resolution computer simulations today can generate great movies and it’s sometimes actually informative to watch them. There are some conferences offering that option now, but it’s not all of them and it’s still mostly in its infancy. But why stop there? How about having plots that move? I’ve often wanted to plot something and wished I could have a moving plot where the line I’m showing would move as a parameter is changed. Unfortunately, we can’t publish that today. I submitted an abstract recently where I had to hammer at the text for 2 days to make it fit in the 4 page limit (ah yes, don’t get me started about page limits) when I could have cut out an entire page if I only would have had an animated figure.

In essence, that’s my take on PLOS. I’m not saying PLOS is bad. PLOS is here to stay and I’m all for any organizationi that offers free access to science with the copyright squarely in the hands of the publishing scientist(s). Everything else is an argument about how to implement the perfect system.

I agree to a certain extent that intellectual property must be protected as to allow an economic motive to generate investment and research, but not at the price of “imprisoning knowledge”. The Creative Commons license is a good place to start. and innovative initiatives like the Public Library of Science (www.plos.org) are beggining to bear fruit. There is hope