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Limacina helicina

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Written by camcarlson

March 30, 2014 at 10:35 PM

Posted in Science

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Flame retardants

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From the New York Times (italics mine):

The problem is that flame retardants don’t seem to stay in foam. High concentrations have been found in the bodies of creatures as geographically diverse as salmon, peregrine falcons, cats, whales, polar bears and Tasmanian devils. Most disturbingly, a recent study of toddlers in the United States conducted by researchers at Duke University found flame retardants in the blood of every child they tested. The chemicals are associated with an assortment of health concerns, including antisocial behavior, impaired fertility, decreased birth weight, diabetes, memory loss, undescended testicles, lowered levels of male hormones and hyperthyroidism.

Heather Stapleton, a Duke University chemist who conducted many of the best-known studies of flame retardants, notes that foam is full of air. “So every time somebody sits on it,” she says, “all the air that’s in the foam gets expelled into the environment.” Studies have found that young children, who often play on the floor and put toys in their mouths, can have three times the levels of flame retardants in their blood as their parents. Flame retardants can also pass from mother to child through the placenta and through breast milk.

Logic would suggest that any new chemical used in consumer products be demonstrably safer than a compound it replaces, particularly one taken off the market for reasons related to human health. But of the 84,000 industrial chemicals registered for use in the United States, only about 200 have been evaluated for human safety by the Environmental Protection Agency. That’s because industrial chemicals are presumed safe unless proved otherwise, under the 1976 federal Toxic Substances Control Act.

When evidence begins to mount that a chemical endangers human health, manufacturers tend to withdraw it from the market and replace it with something whose effects — and often its ingredients — are unknown.

And then there is the graphic below… I was in agreement up until the suggestion to “vacuum with a HEPA filter several times a week.” Overkill perhaps, but the alternative is to replace the furniture with something less toxic.

12-039flameretardants

Written by camcarlson

February 16, 2013 at 11:40 AM

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Over & Over

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A thoughtful article on why people watch/read/do the same things repeatedly:

The responses suggested that sometimes choosing to do something again was about reaching for a sure thing—the brain knows the exact kind of reward that it will receive in the end, whether it is laughter, excitement or relaxation. They also learned that people gained insight into themselves and their own growth by going back for a do-over, subconsciously using the rerun or old book as a measuring stick for how their own lives had changed.

 

Written by camcarlson

January 7, 2013 at 7:32 PM

Posted in Science

Does the universe have a purpose?

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If the purpose was for humans to exist, then the universe procrastinated for 99.9999% of its cosmic history.

Written by camcarlson

December 13, 2012 at 10:59 PM

Posted in Science, video

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Molossus rufu

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Black Mastiff bat embryos.

[h/t: Wired]

Written by camcarlson

October 31, 2012 at 10:58 PM

Posted in Science

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The 10-dimension Omniverse

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Take some time this evening to familiarize yourself with our ten dimensions.

Written by camcarlson

August 20, 2012 at 7:21 PM

7:59:60

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Enjoy your leap second!

The adjustment is needed to reflect a slowing in the Earth’s rotation which gradually prolongs the solar day. The day has not been exactly 24 hours long since 1820. When dinosaurs roamed the planet, the day was only 23 hours long.

The slowing of the earth did not matter much as long as time was measured in accordance with the average rotation of the Earth relative to other celestial bodies. Modern atomic clocks, however, are based on a consistent signal emitted by electrons within an atom. They are accurate to within about one second in 200 million years.

One challenge is that the slowing of the Earth is irregular, influenced as it is by the gravitational pull of the sun and the moon and by unpredictable changes in the atmosphere and in the planet’s molten core.

As a consequence, the scientists charged with measuring the Earth’s rotation determine the timing of leap seconds only six months in advance.

The extra second will occur at 7:59:60pm CST — that is, between 7:59:59 and 8:00:00.

[h/t: NYT]

Written by camcarlson

June 30, 2012 at 4:46 PM

Posted in Science

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