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Archive for October, 2008

Andy Rooney’s world

Sunday, October 26th, 2008

On 60 Minutes today, Andy Rooney talked about unemployment. Mr. Rooney heard that 10 million Americans are unemployed. Andy refuses to believe this–I guess his friends’ kids are working and his powers of observation don’t extend any further than that. He’s the Inspector Clouseau of commentary.

If many people *are* unemployed, Mr. Rooney knows why–people these days won’t work hard. Why, he worked in a paper mill (for a few months when in college) for $0.45/hour. Convert that from 1939 dollars to 2008 dollars and we have $7.08/hr, higher than today’s minimum wage of $6.55/hr. Of course today’s workers have more taken out for Social Security and Medicaid. In 1939 there was no Medicaid and the SS tax was 2% while today they are 15.3% combined, so today’s single worker takes home $5.97. Mr. Rooney’s short term college job is looking pretty good.

Andy Rooney is as out of touch as John McCain, who said in the Republican primary that American workers won’t take jobs picking lettuce for $50/hour, a whole collection of wrong ideas.

Pepper spray antidote

Tuesday, October 14th, 2008

Pepper spray has been around for years now, but there is not commonly available antidote. And we know how the active ingredient, capsaicin acts to active, or hold open, the ion channels that transduce pain signals. In fact, a quick Google shows that capsaicin binds and activates a receptor called the vanilloid receptor subtype 1 (VR1), a member of a group of related receptors called TRP ion channels that are activated by temperature changes.

Capsaicin chemical structure
Capsaicin chemical structure (from Wikipedia)

So an antidote would be an inhibitor of the VR1 receptor, and such a thing should be easy to find, or create, and in fact another Google shows that several have been created. Capsazepine was the first inhibitor discovered, way back in 1994. Activators and inhibitors of this receptor have many potential uses as analgesics and anti-inflammation compounds so there is a lot of research interest.

Capsazepine
Capsaicin inhibitor capsazepine (from Wikipedia)

A spray containing one of these inhibitors should be an effective antidote for pepper spray. But surprisingly no such inhibitor is available! The small quantities of purified inhibitors are available in small quantities for research purposes (i.e. capsazepine, 50mg for $455 but I can’t find anyone who has made an antidote preparation. This should be safe and fairly easy. Safe, because it would be applied mainly externally, and because pepper spray is itself fairly safe–aside from the pain and shock it is used to cause. It doesn’t have other, non-specific side effects. And relatively easy to make because the literature describes the synthesis of inhibitors from capsaicin itself. So the starting product used to make an inhibitor can be capsaicin, and capsaicin is readily available in large quantities!

Update:
Wikipedia: Discovery and development of TRPV1 antagonists

The shape of programmer’s brains

Saturday, October 11th, 2008

I ran across a remarkable paper, “The Camel has two Humps”. Incoming Introduction to Programming students all *want* to learn to program, but about half the class never gets the hang of it and never will. The authors found a test that identifies the students that can learn to program.

The authors’ pretest asks questions about variable assignment: a=10, b=20, a=b. There is a typical meaning for these assignments in programming languages but the incoming students may not know them. So the authors classify the type of logic required to reach different answers and whether the students use the same logic for each question or switch around on different questions. Students who come up with consistent answers for different questions are the students who can learn to program.

Here’s a key figure:
consistent and inconsistent answers corellated with grades

This is remarkable, a way to candle incoming CS students and figure out (mostly) which ones can learn to program.

One notable thing that further research can answer is about the oddballs. The 2-3% of initially inconsistent testers that *do* learn to program–what sort of programmers are they? Do they end up writing different programs than the typical programmer?