Dr. Helen E. Maynard-Casely chats about planets


What to expect on the surfaces of the more distant planets is a hard question to answer. Fortunately, we have scientists working on this problem.

At our institute, we just had the pleasure of hosting a talk by Dr. Maynard-Casely, whose mission is to add a certain amount of evidence-based level-headedness to the discussions. I will do my best to summarize the contents of her excellent and engaging talk. Read more »


Small-angle Scattering: More than nice curves. [Guest post by M. Gallagher-Jones]

Coherent waves emanating from a raindrop impact on water. CC0-licenced image from: http://pixabay.com/en/rain-drops-raindrops-water-drops-71481/

[ed: Marcus Gallagher-Jones just finished his Ph.D. project on VUV and X-ray lasers for imaging of biological macromolecules]

I was happy to receive an invitation from Brian to write a post for his blog. I can honestly say that I owe a good deal of my knowledge of SAXS from helpful discussions with Brian and from reading LaN. Over the years we’ve shared a country, a workplace, and one more important thing: a scattering geometry. So without further ado I’m delighted to introduce to you the technique which has occupied my time for much of the past four years, Coherent Diffractive Imaging (CDI). Read more »


The Dark Side of Science.

Panel from Dresden Codak. Reproduced with permission, Copyright 2011 Aaron Diaz. Source: http://dresdencodak.com/2011/06/16/dark-science-10/

A little step sideways from small-angle scattering for this week’s post. As you are probably aware by now, I sometimes use the LaN weblog to crystallize ideas into something resembling a coherent story. This is needs to be done now, as I am preparing another presentation (due late January), one that covers a tangential topic from my usual repertoire: a little overview of bad tidings in science. Read more »


Error estimation using Fourier Transforms

left: Fourier components and low- and high-pass window. Right: original data, low-pass filtered data, and high-pass filtered data.

Estimating uncertainties on data values has always been an important and under-emphasized part of small-angle scattering. Uncertainties are critical to your data: they tell you what is most likely a real difference, and what is probably just measurement noise. Fortunately, many datasets come complete with data uncertainties, but there are still quite a few cases where this is not the case, or where the provided uncertainty estimates are unrealistic. So what can we do?

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