Friday, March 18, 2011
In yesterday's New York Times, science reporter Bill Broad covered the
projected movement of the radiation plume by the UNs Comprehensive Test
Ban Treaty Organization. The forecast is based on patterns of Pacific
winds and, the predicted path is likely to change as weather patterns
shift." Weather patterns always shift, but for the US any radiation from
the plume will be down to a safe level. What is a "safe" level? It's time
to repeat my "radiation-hormesis" rant.
Airline crews experience a high total-radiation exposure. But the exposure
of airline crews is spread over many years, while Chernobyl survivors got a
concentrated dose. Statistically they are not distinguished. Do the
derivatives matter? According to a story in the news this week, Chernobyl
survivors today suffer cancer at about the same rate as others their age.
The same is true of Hiroshima survivors. If true, it would seem to support
the radiation-hormesis thesis. "Hormesis" refers to things that are toxic
in large doses, but harmless or even beneficial in small doses. Trace
amounts of selenium, for example, are essential for cell function of
animals. But selenium salts in larger doses, are highly toxic. Airline
pilots or not, we are all exposed to background levels of ionizing
radiation every day of our lives. We do not all succumb to cancer. It
seems there is a repair mechanism that compares neighboring strands of DNA
and patches up damage. The comparison can work only if damaged strands are
isolated. If the damage rate is very high, the same repair mechanism could
multiply the damage.
Maxwells equations were published 150 years ago this month in
Philosophical Magazine. This week they are honored in a Nature editorial
as a "bold unifying leap." When first exposed to Maxwells equations as a
student I considered giving up physics. Not because I couldn't understand
Maxwells equations, but because I realized that I could never compete on
that level. But I soon realized that there was only one Maxwell.
Andy White of the Rights and Resources Initiative (RRI), says we need,
Growing Restoration, Employment and Energy Now (GREEN), which is crucial
for the success of Reducing Emissions from Deforestation and forest
Degradation (REDD).
Congratulations! It took six years of looping around solar planets,
including Earth, to enter Mercury orbit perfectly. NASA does planets
really well. Acronyms are another matter. The spacecraft's poetic
sounding name turns out to be a labored acronym: MErcury Surface, Space
ENvironment, GEochemistry and Ranging.
I'll be there to give an invited talk about what's new in Voodoo Science,
Thursday, March 24 at 8:36AM, in C1.
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