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Tuesday, June 23, 2015

Kangaroos are Southpaws in More Ways Than One

     Kangaroos are predominantly left-pawed according to a June 18, 2015, study of Eastern Gray and Red kangaroos published in Cell Biology by Andrey Giljov et al of Saint Petersburg State University. 

     The pawedness of these bipedal marsupials was observed during eating and grooming. A connection to walking on two legs for a paw dominance was noted. Bipedal wallabies (shown below) also showed a left-hand preference. The wallabies used their left paws for fine motor skills and right paws for strength. Quadruped marsupials like tree kangaroos did not show a predominant paw.

      The researchers were surprised to find a dominant paw at all since marsupial brains do not have a corpus callosum, the connecting tissue between the two sides of the brain which humans and many other placental mammals have.

      This Smithsonian article describes the kangaroo research as being useful to understanding dominant handedness in humans. Additionally, left-handedness in humans correlates with less specialized brains.

      Any southpaws out there among PEOTSers? Maizie is right-pawed and I am right-handed.

Chirality yours,

Wednesday, June 17, 2015

Liquid Ferrofluids: Solid Science For Possible Cancer Tumour Treatment

     With all things liquid in mind today, here's the link to  Science Friday's blog's picture of the week and text: Ferrofluids.

     The blog text, reproduced here, includes possible practical applications to directly targeting cancer tumours:

      "Magnets are pretty cool. The way they attract and repel—it’s like magic. But a liquid magnet? That’s even cooler. Called a ferrofluid, such a liquid is comprised of tiny magnetic particles between 10 and 15 nanometers wide suspended in a fluid. In the presence of a magnetic field, the material ebbs and flows according to where the field tells it to go. Instead of an amorphous puddle, it can pool into some funky, spikey shapes—making for some amazing pictures like the bizarrely beautiful one above."

       "This particular photo (above) shows a single drop of a ferrofluid that’s made from magnetic iron particles suspended in oil. To form that pattern, Felice Frankel, a photographer and researcher at MIT, placed a small, three-centimeter-wide drop on a glass slide. Underneath are seven round magnets—like the kind on your refrigerator—arranged so that six of them surround the last. Each magnet forces the particles in the liquid to align with the magnetic field, forming the spikes seen in the photo."

     "To add some color, Frankel inserted a yellow Post-It note in between the magnets and the slide. The image is part of an exhibition at the MIT Museum on communicating science through photography, which is showing from now through March 2016. (Frankel is also co-instructing a course on science photography.)"

     "Ferrofluids, though, have been around since the 1960s. And they don’t all just sit around, looking pretty. For example, they’re widely used as nearly frictionless seals to maintain a vacuum while still allowing for moving or rotating parts. Some computer hard drives, for instance, rely on a magnet to hold a ferrofluid seal in place, which keeps the disk protected in a clean, dust-free vacuum. Because the ferrofluid is liquid, the disk can spin freely with hardly any friction."

     "Understanding ferrofluids can also inform research into fighting diseases like cancer. No, doctors won’t be infusing patients with that black liquid. The idea is to inject magnetic nanoparticles that help deliver tumor-destroying drugs. Their movement through liquids like blood could be controlled by a magnetic field, similar to particles in a ferrofluid."

     "By targeting tumors directly, you can avoid collateral damage to healthy cells. (Cancer drugs tend to be quite nasty and can cause side effects.) But getting those particles to accumulate at the tumor isn’t easy. “That is the biggest challenge in nanomedicine today,” says Carlos Rinaldi, a professor of biomedical and chemical engineering at the University of Florida."

     "One potential way to deliver drugs is with tiny spherical containers called liposomes, which are made of the same stuff as a cell’s membrane. You can fill the liposomes with drugs and attach the nanoparticles on the outside. Once the liposomes reach a tumor, the doctor turns on a magnetic field, which flips the nanoparticles back and forth, like how a compass needle goes crazy when next to a magnet. All that motion generates heat, which melts the liposome and releases the drug."

     "Or, instead of riding in a liposome, the drug could chemically bind to the nanoparticles. The magnetically induced heat would then break that bond and unleash the drug. The heat itself could also help kill the tumor, as some drugs work better at higher temperatures."

     "Saving lives drives much of the research in ferrofluids, of course. Still, you can't discount their mesmerizing patterns and behaviors. After all, that’s what inspired Rinaldi to study ferrofluids in the first place. "The idea that you can use a magnet to manipulate a liquid—to me, that's just so cool," he says."

     And if you want to make your own ferro-fluid, here's 4-minute video:

Fun with Ferrofluids: Making Your Own

Let me know how it turns out; I don't want to see any more liquids right now,


Wednesday, June 10, 2015

Trilobite Bottoms: Molting, Molting, Molting

      Trilobite bottoms (or pygidia) are found in sedimentary rocks, evidence of the molting life cycle of these intriguing fossils.

      The fossilized remains of these primarily Paleozoic fossils sometimes show the molting process quite distinctly:

     Rather than finding the whole fossil with its namesake distinct three parts

sometimes only the trilobite bottoms are found:

      Molting, molting molting. . .

      When first searching the web for trilobite bottoms here's the image that popped up first:

      Trilobite bottoms came up as a topic for this week's PEOTS as I was planting artichoke plants (nasty, spiky, weedy looking things):

        It was a small leap from artichoke bottoms (which are, of course, also known as hearts)

to trilobite bottoms. . . .

Looking forward to Tri lo bite of the artichoke bottoms soon!


And for those science grads:


Tuesday, June 2, 2015

Cherry Blossom Stones : I Knew I Muscovite Away

     Cherry blossom stones (or "pinite") are a complicated group of six cordeirite crystals surrounding a central indialite crystal which have all then been replaced by muscovite in a second metamorphic event. I knew I muscovite about them after reading about them for the first time today.

      The structure of the stones is shown in this illustration (please forgive the 'intergorth' typo:

     The dumbbell structure including the central indialite crystal creates these intriguing stones which are not fossils:

      The type locality is near Kyoto, Japan, of all perfect prefecture places. And these stones are found in a hornfels (metamorphosed shale or mudstone) matrix. 

     So much change in temperature and pressure in those metamorphic rocks to create these delicate hexagonal structures! The end result are muscovite replacement crystals of these cordeirite-indialite crystals all on the hornfels rock.

        Chemically, indialite is a magnesium aluminosilicate mineral (Mg2Al4Si5O18).  Cordierite is an iron magnesium aluminosilicate mineral ((Fe,Mg)2Al4Si5O18).

      Have you heard of cherry blossom stones before? Does the complex interrelationship of the host rock, original crystal structure of two different minerals then replaced by another mineral in a hexagonal structure make you say "Wow?!"

Whoa. Wow,


New canine mountain friends on a perfect Colorado Day:

        We said our Colorado au revoirs this weekend. . . ZOË is Addis Ababa bound, home-made injera sourdough flat bread in hand ;-). A most excellent adventure until September, 2017; Colorado peeps will miss you! Excited to hear about your grand adventure!