Monthly Archives: November 2006

Imaging hA3G

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I am under the impression that the image above shows the first-ever “snapshot” of the structure of an enzyme that could help resist HIV and the onset of AIDS.

According to an article from Reuters, some small percentage of people possess hA3G in spades, and they can fight off the effects of HIV for longer than others. The question is how. Knowing what the enzyme looks like helps scientists understand the chemical processes better and could help “design a drug to mimic its effects and perhaps provide the first medicine to boost the ability to fight AIDS,” as the Reuters reportage puts it.

According to the associated research article, “high-molecular-mass (HMM) complex […] can be transformed in vitro into an active, low-molecular-mass (LMM) variant comparable to that of HIV-non-permissive CD4+ T-cells.” Which seems to be something good.

The point, as far as this blog is concerned, is that the general structure of this important compound has been unlocked—or at least the first steps have been taken to understanding more about its elusive nature. Moreover, the spatial depiction of the chemical structure is fundamental to unlocking its secrets. And that’s what visualization is all about.

Bloody Palpitations

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The above image comes from a press release from MIT (which can be read ina recent issue of MIT’s Tech Talk as well) that describes work being done on imaging living cells. The cells in question (as the colors chosen for the height scale so transparently suggest) are red blood cells, and the “quantitative phase imaging” technique allows for observations of the cells’ shapes down to a few nanometers.

The spiffy thing? High resolution in scale allows us to see fluctuations in the membranes as they allow ions into and out of the cell. Cells prone to swelling can burst, and swollen cells also palpitate less, so studying their motion numerically is a boon to understanding the physical processes at work. This could help us understand diseases such as malaria and sickle-cell anemia at the scale of the blood cells themselves.

(As far as I understand, quantitative phase imaging has been used in Transmission Electron Microscopy (TEM) for some time, so its application in light spectroscopy is a new thing. Especially since you can’t use TEM to observe living cells. Just FYI, this differs from the technique I’d described earlier on this blog for tagging individual stem cells in bone marrow.)

I quite like the image above. What’s the Hitchcock quote? “Blood is jolly, red.” You take one look and you get a general sense of what’s going on, and the scale to the right provides a little more info. Nice.

Numerous other pictures accompany the press release, including a series of false-color images that reveal both normal and abnormal cells. Sadly, the captions shed little light (spectroscopic or otherwise) on what the images actually depict. Particularly egregious is a rather incomprehensible figure—according to its caption, it “shows the correlation between cell shape and membrane dynamics,” but what exactly does that mean? Of all places, it seems that MIT would want to present imagery that could be read across a variety of technical disciplines, and this figure doesn’t cut it! Couldn’t we get more information than “Δu&sup2(q)” versus “q” (although they kindly include units)? I’ll tell you this much—a little research revealed that “discocyte,” “echinocyte,” and “spherocyte” refer to diffferent red blood cell morphologies (cf. a “scientific highlight” from Australia for more information).

My gripe here is just that captions, particularly in press releases, should give enough information for a well-informed non-specialist to get a handle on the information being presented. After all, science reporters are most likely generalists who will appreciate whatever cues you can provide.

(Thanks to Phile Schewe and his “Physics News Update.” Also, I ran across another informative web site in my searches. Lots of info about cell biology. And very difficult quizzes!)

Airport Images

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Having returned to New York from my trip, I figured I could offer two airport observations…

While waiting for my flight at the Lousiville International Airport, I had a good view of a pari of video panels set up by the Standiford Art Foundation as part of their “Video Art Project.” The three pieces each had their merits, but I found myself mildly intrigued by Thomas C. deLisle’s “Transition” (2005), which consisted entirely of Earth imagery from orbit.

I should first note that the screens were situated slightly off the beaten path (albeit on the way to restrooms, which is often a good thing), so no more than fifty or sixty people passed by in the hour or so I sat nearby. Of those, only five or six stopped to look, and highly subjectively, I’d say that the terrestrial imagery held their attention longer than the other pieces—one a somewhat abstract view of reflections on water, the other a continuous drive-by of suburbia. But people didn’t linger very long, usually only fifteen or twenty seconds and only once more than a minute.

The problem I had with the piece was the rapidity with which images cut from one to the next, leaving little time to absorb anything within the frame. Plus, the physical set-up consisted of two screens with separate content on both, making the transitions feel even faster-paced. I kept looking for some connection between sequential frames or paired images, but none struck me. Between the speed of cuts and the randomness of the images, the net effect was a bit like watching a screen saver with poor settings. But the Earth stuff seemed to have a slight allure for passers-by… Perhaps if it had offered more time to absorb the visuals?

On a related airport topic, I also took a look at Accenture’s interactive video wall at O’Hare International Airport. This has nothing to do with science, per se, but in fact, it would be nice if it did! When you step up to the screen, you’re given options for “Weather,” “News,” “Sports,” “Entertainment,” and “Tiger Woods.” Why not “Science”? Given the degree to which science and technology affects our lives, it seems like a no-brainer. Then we could implore Accenture for data on how often people select the “Science” option relative to others.

I’ve read some rather critical appraisals of the technology, but in fact, people spent a bit of time interacting with the thing (more than looked at the video art in Louisville, that’s for sure), and its interface felt completely transparent to basically everybody who stepped up to the screen. That strikes me as successful. I mean, the Windows-like grassy field and blue sky kinda creeps me out, but even I won’t hold that against ’em. Too much.