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Archive for the ‘science’ Category

Genetic Mythbusters


In my continuing quest to unravel the genetic mystery of my son’s wet ear wax, cloverleaf tongue-folding ability, and shovel-shaped teeth I stumbled across John H. McDonald’s “Myths of Human Genetics.” He describes that while tongue-rolling and other traits are common examples used by teachers for basic genetics, those traits aren’t all simply expressed by dominant/recessive genes. Tongue-rolling is partially genetic but studies have found non-rolling parents with rolling kids. So it’s not a good basic example though it’s often used in introductions to genetics. Among his many well laid out examples is my nemesis, yes the wet earwax, which is one that actually is a simple dominant/recessive situation but isn’t used much as an intro example, likely because of homogenous school populations and grossness.

Posted in science

USGS Historical Topographic Maps Online


The U.S. Geological Survey started creating topographic maps in 1884. They don’t even know how many maps they’ve produced since then but they’re estimating it at 200,000. It’s such a fascinating endeavor and they’ve written papers on its history. Their National Geospatial Program is scanning all of the old topographic maps into electronic format and making them available for free download. 90,000 are available already. You can also order a reasonably priced print, the same paper format many of us are familiar with for modern USGS topographic maps (available at stores that cater to hikers like REI). The maps are in GeoPDF format, viewable in Adobe Reader and you get even more functionality with the TerraGo Toolbar extension. I downloaded Mount St Helens from 1919. Yup, it’s a lot different now. And back then the maps were all done by people hiking around taking measurements. (Here’s more geeky detail on Mount St Helens topography if you’re interested.)

Posted in nostalgia,science

Polymer Gel Vocal Cords


Julie Andrews’ scarred vocal cords robbed us of  her lovely soprano. Other people with cancer, intubation scars, vocal strain, or other throat conditions suffer even more loss of their speaking and singing abilities.  When Andrews went to Dr. Steven Zeitels, a Harvard professor specializing in laryngeal surgery, she learned of the project he and Robert Langer, a MIT professor in chemical engineering, had been working on to simulate vocal cords with a polymer gel. Langer’s lab started with polyethylene glycol, used in numerous medical and other applications. They’ve altered the arrangement of the molecules so that the gel vibrates the same way as vocal cords do when air passes by. When injected into scarred vocal cords, the gel can restore the behavior of the patient’s vocal cords, hopefully restoring their voice. The team hopes to start human trials next year. The Institute of Laryngology and Voice Restoration, which brought Julie Andrews in as honorary chairwoman and counts rock musicians Roger Daltrey and Steven Tyler among its supporters, helped to fund the research. Below is a short video of the gel compared to human vocal cords.

Posted in science