405 nm laser fun

May 26, 2011 at 5:39 pm | | nerd, science and the public, science@home

I bought a 10 mW (30 mW, actually, according to our lab’s power meter) 405 nm laser from Amazon. No this pointer isn’t for presentations, for reasons I have already stated. This pointer is for fun.

For instance, I’ve enjoyed shooting the beam through tonic water and seeing the fluorescence from quinine. Here’s some total internal reflection:

Any other ideas for cool “experiments”?

(Note, please be careful with this or any laser pointer. Although the purple light emanating from this pointer doesn’t look bright, it can damage your eye or skin. Even if your eyes aren’t sensitive to 405 nm, that doesn’t mean they can’t be damaged by 405 nm. This pointer is dangerous to be viewed even in diffuse reflections.)

(P.S. The sorta shitty photo credited to E.Y.L.)

UPDATE: It turns out that urine is also fluorescent:

Especially after taking a multivitamin.

extraordinarily repeatable data

May 3, 2011 at 5:31 pm | | crazy figure contest, literature, scientific integrity

UPDATE: My friend on Facebook pointed out that Figure S5c in the supporting info is even more fishy (click on the image below to see a zoomed-in version). Clearly, some portions of the image were pasted on top of other parts. On the right, it is obvious that the top part of the image is from a different frame as the bottom part. On the left, it looks like there’s another image hidden behind (see the strip showing through on the left top part of the image). I’ve added red arrows to aid the eye.

This could possibly be mistakes by someone who doesn’t know how to use Photoshop layers, but I’m thinking there might have been some intentional manipulation of the data. Either way, this type of slicing and stitching and Photoshopping of scientific data is totally unacceptable. I think Nature editors and referees should be more than ashamed to have let this slide.

Nature editors announced that they are investigating.

(Original post below.)

This paper in Nature contains some serious errors: some of the images that are purportedly from different samples (different mice, even) appear to be identical! Note the triangle of spots in the two images below:

Many commenters have noticed the weirdnesses in the figures. This is my favorite comment so far:

2011-04-22 09:31 AM aston panda said:
This is an excellent article shows extraordinary .. skills and amazingly repeatable data. for example
Fig.1a, 2 middle vs 3 bottom left
Fig.1c, 2 right side vs 3 left side
Fig.S4, 1 left side vs 2 right side
Fig.S5, c4 middle right vs e4 middle left

I suspect that some sloppy organizing by the authors led to them mixing up some files on their computer. That’s my optimistic view. If they were trying to fabricate data, they wouldn’t use the same region of the same image of the same sample! It must have been sloppy bookkeeping. I hope their results stand up after they correct these errors.

It just goes to show that real science can’t get accepted into Nature and Science. ;)

UPDATE 2: RetractionWatch is surprised that this paper eventually was published with only a correction!

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