Scientists have re-created the deadly 1918 flu virus and used it to infect animals. WTF?
3 days ago in Genomics, Medicine, and Pseudoscience
A plant pundit comments on plants, the foibles and fun of academic life, and other things of interest.
3 comments:
Cool! I only just recently heard about this phenomenon. Lots of pretty pictures here: http://www.kuriositas.com/2012/12/frost-flowers-natures-exquisite-ice.html
TPP, I've seen these on dead wood, stumps, and coming up through gravel and rocks. Your comment about root pressure may be somewhat true, but it may not have any role to play, either. The ice forms at the interface of the luquid stage inside the object, and the liquid water feeds the expanding solid phase at that point. I don't think active transpiration or other "pushing" is needed. The solid ice pulls the liquid to the point where it can phase shift to solid. BTW, I belive the liquid is super-cooled at this point, as well, and is just waiting for an initiating event to convert to solid form.
Well, Dr. Chips really makes some good points as he usually does; dead stumps definitely don't have root pressure. I'd only ever seen them on herbaceous perennials. And I hadn't thought about super-cooled water. Guess that's my problem: it's more physics than biology. Drat!
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