parakkum

Over at this post on his blog, Alex Epstein relays the tale of how Axel Alonso randomly seeing a hilarious LoLMonkey caption led directly to the (real) Marvel comic Hitman Monkey.

Posted by parakkum at 11:47 AM | Permalink | Comments (0)

Posted by parakkum at 03:03 PM | Permalink | Comments (1)

Christopher Carr and Jeremy McGee of MIT recently published The Apollo Number: Space Suits, Self-Support, and the Walk-Run Transition, which explores the origin of the difference between an earthbound walk-run transition and the same event under varying gravity conditions in space suits.

The walk-run transition is exactly what it sounds like - the velocity at which we switch from walking to running as we speed up (or vice-versa, of course, as we slow down). As we might imagine, space suits modify the velocity of the walk-run transition. As you may or may not know, this is significant, since a suited individual operating under reduced gravity uses less energy to run rather than walk the same distance, possibly due to "spring" effects of running in a pressurized suit versus the hard work of slogging slowly forward in the same suit.

Carr and McGee modify the usual walk-run transition formula to include an "Apollo" number that factors in the percentage of human-supported to total transported mass. This is significant since a pressurized suit in a vacuum is self-supporting - if you filled a space suit and carefully set it up outside on the moon, it would stand on its own. While this does impart the rigidity that makes walking in a suit so hard, it also means the wearer isn't working to hold the suit's weight up, which in turn modifies the velocity of the walk-run transition.

The practical impact of this is that we now have a formula that is better adjusted to predicting in advance (and presumably manipulating) the walk-run transition velocity for suited individuals...and, as the authors note, "suited" in this sense includes both astronauts in spacesuits and exoskeletons operating on Earth.

So one step closer to Cyclones for all of us.

Carr CE, McGee J (2009) The Apollo Number: Space Suits, Self-Support, and the Walk-Run Transition. PLoS ONE 4(8): e6614. doi:10.1371/journal.pone.0006614

Posted by parakkum at 10:57 AM | Permalink | Comments (0)

You're looking at a mobile phone fitted with an adapter that turns it into a microscope capable of light and fluorescent microscopy, able to resolve cells and microbes, that can be used to carry out field evaluations of malaria, TB, and other conditions that would normally require expensive lab equipment that third-world regions may not have access to.

In their article Mobile Phone Based Clinical Microscopy for Global Health Applications, Breslaur et al have leveraged the ubiquity of mobile phones across the world, including the third world, to provide an invaluable health care tool for areas that desperately need it. In this work, they use their mobile-adapting microscope to identify malaria, tuberculosis, and sickle-cell anemia, including the use of automated image processing:

In addition to the capture and transmission of data, the fact that mobile phones are essentially embedded computer systems offers the opportunity for significant post-processing of images. To demonstrate the diagnostic potential of image processing in this application, we carried out automated bacillus counting of the fluorescent TB images.

This is an impressive development that hopefully will be put into production quite rapidly. As comments already present on the article note, this is important as a public health development for much of the world and it promises to be a pretty cool device for biology hobbyists, too.

The article:

Breslauer DN, Maamari RN, Switz NA, Lam WA, Fletcher DA (2009) Mobile Phone Based Clinical Microscopy for Global Health Applications. PLoS ONE 4(7): e6320. doi:10.1371/journal.pone.0006320

Posted by parakkum at 01:17 PM | Permalink | Comments (0)

In a paper published this month in PLoS One, Elise Nowbahari, Alexandra Scohier, Jean-Luc Durand, and Karen L. Hollis reveal some exciting work in an oddly under-studied area - rescue behavior in animals. Humans clearly engage in rescue behavior, often to our own detriment, and we make complex decisions about whom we choose to try and rescue. You'd rescue your own kid. Would you try to rescue a cousin? A neighbor? A total stranger?

In this work, ants of the species Cataglyphis cursor were faced with a series of potential rescue situations, including:

• A trapped Cataglyphis cursor from their own colony
• A trapped Cataglyphis cursor from another colony
• A trapped ant from another species
• A trapped prey animal
• A trapped Cataglyphis cursor from their colony, chilled into inactivity
• No trapped animals

The results were quite specific: The ants only attempt to rescue active members of their own colony. They do this by digging away at surrounding sand, tugging on limbs (but not antennae!), and biting at the nylon snare trapping the ants.

This is fascinating work that brings up even more exciting future directions for research. As the authors conclude:

In sum, our findings establish that, in Cataglyphis cursor, rescue behavior not only is directed exclusively toward nestmates but also the nestmate must be active. Thus, rescue behavior necessarily depends on some form of actively produced eliciting stimulus, already known to be a pheromone in several ant species but one that contains a component unique to each colony.

What is the "help me" signal? Is that snare biting highly specific, or part of a general clearing of foreign matter from the problem area? How complex (versus, say, programmed) is this behavior?

I've also reposted their supporting videos to YouTube under PLoS One's Creative Commons license. They're worth a look:

You can read the original article by clicking here.

Posted by parakkum at 04:30 PM | Permalink | Comments (0)

Want to make a low-cost laminar flow chamber, perhaps for some light microscopy work? Check out the snappily named Fast Benchtop Fabrication of Laminar Flow Chambers for Advanced Microscopy Techniques by David S. Courson and Ronald S. Rock of the University of Chicago.

They describe a straightforward method for handbuilding a chemically inert, reusable laminar flow chamber in about an hour. I'm not currently in a position to need a laminar flow chamber, but this is a nice set of directions for anyone who might want to do some microfluidics work without having to go to a machine shop for expensive, custom-made flow assemblies.

Posted by parakkum at 08:28 PM | Permalink | Comments (0)

From the 2007 San Diego Comic Con:

Pretty much how I feel whenever I see a "free hugs" sign. Perhaps I'm a misanthrope - I always want to just plant a solid kick in the person and keep moving.

Posted by parakkum at 10:42 AM | Permalink | Comments (0)