Ancient Roman concrete is still standing strong after thousands of years and, not only does it resist damage, but the salt water actually makes it stronger. X-ray examinations may have found the key to the concrete's amazing longevity, which could help improve modern concrete recipes. Dissolving phillipsite in pumice, as seen in this Scanning Electron Microscope (SEM) image, is believed to be part of the secret:
Note that modern sea walls last only a few years in salt water where these Roman sea walls have lasted thousands of years.
Although the complete recipe has been lost over the years, studies of samples have shown that volcanic ash, lime, and seawater are the main ingredients. "But, according to an article published in American Mineralogist the real magic seems to happen when those ingredients interact with the environment – specifically the saltwater incessantly pounding on the surface."
Al-tobermorite is part of the cementing matrix, key to its strength. Modern "Portland cement" relies more heavily on heating the elements, exacting an environmental toll.
Huzzah for the ancient Romans. . .and for seawater! Has this idea been cemented in your brain?
Steph
Pink Martini and Rufus Wainwright at Red Rocks, July 6, 2017:
I am fascinated by these redheaded pine sawflies (Neodiprion lecontei) on my geology professors' Mugo Pine (Pinus Mugo):
The sawfly was not a major pest problem in Mugo and other pines in the U.S. until the planting of large pine plantations in the 1930's.
The sawflies resemble caterpillars but are actually members of the wasp/bee family, not the butterfly/moth family. Caterpillars have up to 5 pairs of abdominal prolegs. Sawfly larvae have six or more pairs of abdominal prolegs:
Another notable difference, though it requires a much closer look (oh, yeah!), is that caterpillars have tiny hooks called crochets, on the ends of their prolegs. Sawflies don't. Here are the crochets on caterpillars (C on C as a way to remember the "cats" [entomologists' affectionate pet name for caterpillars] differentiation from sawflies):
And the Scanning Electron Microscope version of the crochets:
The common name of sawfly comes from the saw-like appearance of the ovipositor, or egg depositor, which the females use to cut into the plants where they lay their eggs.
The insecticides that are used on the caterpillar family do not work on sawflies. [And, of course, many caterpillars transform into much-needed and wanted butterflies.]There are some wasp/sawfly insecticides that are somewhat effective, including organic diatomaceous earth (remember the diatoms from our Scanning Electron Microscope {SEM } discussion earlier?):
However, one of the best ways to get rid of the sawfly larvae is to simply pull them off the Mugo pine trees. Any volunteers to get in there, count legs, and pull off the large clumps of sawflies? If so, they are in Northampton, Massachusetts, waiting for you. {Eric Carle used to be there, too, for over 30 years, though he recently moved southward to North Carolina and Florida.}
Wonder if Eric Carle ever counted pro-legs on caterpillars. . .
Any good caterpillar or sawfly tales? Might we count on you?
Steph
Here is an image from the August 4, 2015, Las Animas River after a 3,000,000+* gallon spill from the Gold King Mine in southwest Colorado (see link to article in 8/7/15 comment):
Indeed, next week's Partial Ellipsis will look at the Animas River Spill in Colorado. Please look there for a discussion of the Gold King Mine. I am cleaning up some of the graphs, have some new local photos to share, etc.
*Updated from the original EPA estimate of 1,000,000 gallons.
Juxtaposing close-up views from a Scanning Electron Microsope (SEM) with views from space is this week's Partial Ellipsis of the Sun topic. Throw in some SEMantics or semANTICS and we've got some fun words to go with those images. And, a little venture into SEMiotics will round out today's blog.
Firstly, guess what's in this SEM image:
Hint: Hair is involved. Yes, it's a louse egg or nit clinging to a human hair. No wonder nit-picking takes so much focused time and energy!
Here are eyelashes and human skin:
How about this SEM image?
It is an image of the surface of a strawberry.
Lego brought up the surface of a tongue last week. Here's a human tongue in a SEM:
And lastly,
Any ideas? Hair? Fur? Origami? Fiber optics? Wild psychedelic drug images?
It's an SEM image of a caffeine crystal(!). . .which should provide enough energy to rocket into space via NASA astronaut Reid Wiseman to view this Pacific Coast sunset:
How about this image? Are we looking at a close-up of a spider on the right side of the image or is this an image of solar flares . . .or something else? Not always easy to tell from what perspective you are seeing, is it?
I promised semANTICS. Here you go:
It's an SEM image of a wood ant with a microchip. Wonder what sort of semiotic message this image is sending?
According to Wikipedia "Semiotics is the study of meaning-making, the philosophical theory of signs and symbols. This includes the study of signs and sign processes of indication, designation, likeness, analogy, metaphor, symbolism, signification, and communication. Semiotics is closely related to the field of linguistics, which, for its part, studies the structure and meaning of language more specifically. As different from linguistics, however, semiotics also studies non-linguistic signs and symbols."
In semiotics news last month, New York state announced that is will be updating the handicapped symbol (and accompanying verbiage to read "Access") on signs to reflect a more active, moving person in a wheelchair. It's the first major symbol update in over 45 years:
Semiotic update to handicapped sign
I'd relish hearing your perspective on these images and words from SEMantics to SEMiotics.
It's a small (and large) world after all.
Signed ;-),
Steph
(Word Woman)
Here's the mystery sign. What does it mean?
Semiotic shoes at the edge of the Blue Danube (see description in comments section from 08/06/14):
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