Tag Archives: cross section

The secret math of plants: UCLA biologists uncover rules that govern leaf design

Life scientists from UCLA’s College of Letters and Science have discovered fundamental rules of leaf design that underlie plants’ ability to produce leaves that vary enormously in size. In their mathematical design, leaves are the “perfect machines,” said Lawren Sack, a professor of ecology and evolutionary biology and senior author of the research.

The UCLA team discovered the mathematical relationships using “allometric analysis,” which looks at how the proportions of parts of an organism change with differences in total size. This approach has been used by scientists since Galileo but had never before been applied to the interior of leaves. (more…)

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How some leaves got fat: It’s the veins

Some plants, such as succulents, have managed to grow very plump leaves. For that to happen, according to a new study in Current Biology, plants had to evolve 3-D arrangements of their leaf veins in order to maintain adequately efficient hydraulics for photosynthesis.

PROVIDENCE, R.I. [Brown University] — A garden variety leaf is a broad, flat structure, but if the garden happens to be somewhere arid, it probably includes succulent plants with plump leaves full of precious water. Fat leaves did not emerge in the plant world easily. A new Brown University study published in Current Biology reports that to sustain efficient photosynthesis, they required a fundamental remodeling of leaf vein structure: the addition of a third dimension. (more…)

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New Tool for CSI? Geographic Software Maps Distinctive Features inside Bones

COLUMBUS, Ohio – A common type of geographic mapping software offers a new way to study human remains.

In a recent issue of the American Journal of Physical Anthropology, researchers describe how they used commercially available mapping software to identify features inside a human foot bone – a new way to study human skeletal variation. (more…)

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UA Professor Uses Aerospace Materials to Build Endless Green Pipeline

Carbon fiber fabric and lightweight honeycomb materials, plus a mobile manufacturing platform, make infinite pipeline technology cheaper and greener while boosting local economies.

Mo Ehsani, professor emeritus of civil engineering at the University of Arizona, has designed a new, lightweight underground pipe he says could transform the pipeline construction industry.

Instead of conventional concrete or steel, Ehsani’s new pipe consists of a central layer of lightweight plastic honeycomb, similar to that used in the aerospace industry, sandwiched between layers of resin-saturated carbon fiber fabric. (more…)

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Chemists Advance Clear Conductive Films

Thin, conductive films are useful in displays and solar cells. A new solution-based chemistry developed at Brown University for making indium tin oxide films could allow engineers to employ a much simpler and cheaper manufacturing process.

PROVIDENCE, R.I. [Brown University] — In a touch-screen display or a solar panel, any conductive overlay had better be clear. Engineers employ transparent thin films of indium tin oxide (ITO) for the job, but a high-tech material’s properties are only half its resume. They must also be as cheap and easy to manufacture as possible. In a new study, researchers from Brown University and ATMI Inc. report the best-ever transparency and conductivity performance for an ITO made using a chemical solution, which is potentially the facile, low-cost method manufacturers want.

“Our technology is already at the performance level for application in resistive touch screens,” said Jonghun Lee, a Brown chemistry graduate student and lead author of the paper posted online Aug. 1 by the Journal of the American Chemical Society. (more…)

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Prehistoric Predators with Supersized Teeth Had Beefier Arm Bones

*Combination of colossal canines and forceful forelimbs arose repeatedly over time*

The toothiest prehistoric predators also had beefier arm bones, according to results of a study published today in the journal Paleobiology.

Saber-toothed tigers may come to mind, but these extinct cats weren’t the only animals with fearsome fangs.

Take the false saber-toothed cats–also known as nimravids–and their catlike cousins, a family of carnivores called the barbourofelids. (more…)

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