Author Archives: curiouscat

Math and Nature

Give mathematicians such a toy, and they’re liable to turn it into a math problem.

…
Next, the pair began to investigate whether all three-dimensional shapes have at least two stable and two unstable balance points. They tried to generalize their two-dimensional proof to higher dimensions, but it didn’t hold up. Therefore, it seemed possible that a self-righting three-dimensional object could exist. Such a shape would have only one stable and one unstable balance point.
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Once the pair had built their Once the pair had built their self-righting object, they noticed that it looked very much like a turtle. They figured that wasn’t an accident, since it would be useful for a turtle never to get stuck on its back., they noticed that it looked very much like a turtle. They figured that wasn’t an accident, since it would be useful for a turtle never to get stuck on its back.
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The mathematicians still face an unanswered question. The self-righting objects they’ve found have been smooth and curvy. They wonder if it’s possible to create a self-righting polyhedral object, which would have flat sides. They think it is probably possible, but they haven’t yet managed to find such an object. So, they are offering a prize to the first person to find one: $10,000, divided by the number of sides of the polyhedron.

And Now for Something Completely Different

Macavity the cat

Too cool. Mystery cat takes regular bus to the shops:

The cat was nicknamed Macavity after the mystery cat in T.S Elliot’s poem. He gets on the bus in front of a row of 1950s semi-detached houses and jumps off at a row of shops down the road which include a fish and chip shop.
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Driver Bill Khunkhun, 49, who first saw the cat jumping from the bus in January, said: “It is really odd, the first time I saw the cat jumping off the bus with a group of passengers. I hadn’t seen it get on which was a bit confusing. “The next day I pulled up on Churchill Road to let a couple of passengers on. As soon as I opened the doors the cat ran towards the bus, jumped on and ran under one of the seats, I don’t think any of the passengers noticed. “Because I had seen it jump off the day before I carried on driving and sure enough when I stopped just down the road he jumped off – I don’t know why he would catch the bus but he seems to like it. I told some of the other drivers on this route and they have seen him too.”

Here is T.S. Eliot’s poem:

Macavity’s a Mystery Cat: he’s called the Hidden Paw-
For he’s the master criminal who can defy the Law.
He’s the bafflement of Scotland Yard, the Flying Squad’s despair:
For when they reach the scene of crime-Macavity’s not there!

Macavity, Macavity, there’s no one like Macavity,
He’s broken every human law, he breaks the law of gravity.
His powers of levitation would make a fakir stare,
And when you reach the scene of crime-Macavity’s not there!
You may seek him in the basement, you may look up in the air-
But I tell you once and once again, Macavity’s not there!
Continue reading →

Changing the Circadian Clock with the Seasons

Changing the Circadian Clock with the Seasons:

The findings – gleaned from work on the fruit fly Drosophila – have broad implications for understanding how innate behaviors such as mating, migrating, and hibernating are stimulated by environmental cues. Dan Stoleru, the lead author of the Cell paper and a postdoctoral fellow in Rosbash’s laboratory at Brandeis University, adds that the study reveals insights into possible causes of seasonal depression as well as other forms of mood disorders that respond to light therapy.
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Rosbash is a leader in the field of circadian research. For the past 25 years he has been defining the machinery that underlies the nearly universal pattern of circadian rhythms in insects, animals, and humans. He employs the tools of Drosophila genetics to understand how the circadian clock ticks and which master neural circuits underlie circadian activity patterns.

Lego Autopilot Project Update

An update to, The sub-$1,000 UAV Project from Chris Anderson – Lego Autopilot is Working!:

Our summer project is to create a sub-$1,000 UAV as a proof-of-concept for a drone competition for kids. This weekend we passed a major milestone with a successful ground test of the key elements. The video below shows the prototype working.

We’d initially intended to do all the autopilot functions in Lego, but the gyro programming turned out to be beyond our abilities. So we switched to a commercial stabilization unit to keep the plane level and just use the Lego Mindstorms for waypoint navigation.

Very cool.

Young Scientists Design Open-Source Program at NASA

Young Scientists Design Open-Source Program at NASA:

The program was launched quietly last year under NASA’s CoLab entrepreneur outreach program, created by Robert Schingler, 28, and Jessy Cowan-Sharp, 25, of NASA’s Ames Research Center in Mountain View, California. Members of the CosmosCode group have been meeting in Second Life and will open the program to the public in the coming weeks, organizers said.

“NASA is recognizing the value of free and open-source software in other sectors,” said Cowan-Sharp, a contractor at NASA Ames in Mountain View, California. “CosmosCode is going one step further by allowing NASA scientists to begin a software project in the public domain, leveraging the true value of open-source software by creating an active community of volunteers.”

CosmosCode is indicative of a larger shift at NASA toward openness and transparency — things for which complex and bureaucratic government labs are not known. The software project is part of CoLab, an effort to invite the public to help NASA scientists with various engineering problems. NASA is also digging into its files from previous missions and releasing code that until now remained behind closed doors. Together, these projects are creating a sort of SourceForge for space.

Related: CosmosCode – Second Life Intern – NASA CoLab

Math’s Architect of Beauty

Math’s Architect of Beauty – How Terence Tao’s quest for elegance earned him a Fields Medal and a MacArthur Fellowship

The prime numbers do obey some simple patterns—for instance, all primes but 2 are odd numbers. The great achievement of the Green-Tao theorem is its use of subtle and novel methods of harmonic analysis (very much indebted to the work of 2002 Fields Medalist Timothy Gowers) to show that these simple patterns are essentially the only structure the primes possess. Beyond these basic structures, the primes look random—they are, in a sense, all noise and no music.

Related: Terence Tao – math related posts

Bedbugs Are Back

Bedbugs bounce back: Outbreaks in all 50 states by Meredith May:

Pest control companies nationwide reported a 71 percent increase in bedbug calls between 2000 and 2005. Left alone, a few bedbugs can create a colony of thousands within weeks. “We never treated bedbugs until 2002. Now we have a dedicated bedbug crew working on this every day,” said Luis Agurto, president of Pestec in San Francisco.

Agurto’s arsenal includes a vacuum, steam heat to cook the bedbug eggs and targeted spraying of insecticides. It takes three, eight-hour visits and about $500 to $750 to exterminate one room. A whole house would cost closer to $5,000.
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Nearly all exterminators use pyrethroids, which are a synthetic version of pyrethrum, the substance found in chrysanthemum flowers. But last fall, at the University of Kentucky, some of the nation’s best bedbug researchers delivered some sobering news — while they could kill bedbugs born in the lab with pyrethroids, four groups of adult bedbugs brought in from the outside were unaffected.

University extension offices often have the soundest scientific information – try the links below for more details.

CERN Pressure Test Failure

photo of Femilab inner triplet quadrupole at CERN

On March 27th a high-pressure test at CERN of a Fermilab-built ‘inner-triplet’ series of three quadrupole magnets in the tunnel of the Large Hadron Collider failed. Fermilab Director on the test failure:

We test the complex features we design thoroughly. In this case we are dumbfounded that we missed some very simple balance of forces. Not only was it missed in the engineering design but also in the four engineering reviews carried out between 1998 and 2002 before launching the construction of the magnets. Furthermore even though every magnet was thoroughly tested individually, they were never tested with the exact configuration that they would have when installed at CERN–thus missing the opportunity to discover the problem sooner.

We need and want to make sure that we find the root causes of the problem and from the lessons learned build a stronger institution. Beyond that, there is no substitute for the commitment each of us makes to excellence, to critical thinking and to sweating every detail.

In a Fermilab Update on Inner Triplet Magnets at LHC they state: “The goal at CERN and Fermilab is now to redesign and repair the inner triplet magnets and, if necessary, the DFBX without affecting the LHC start-up schedule. Teams at CERN and Fermilab have identified potential repairs that could be carried out expeditiously without removing undamaged triplet magnets from the tunnel.”

Bisphenol A

Bisphenol A is a chemical compound used in plastics (and contained in many beverage and food container – water bottles…). There is debate over how dangerous it is. Studies have found health problems in animals and people (due to Bisphenol A exposure) but whether those studies indicate there is any problem with the real life exposures today is questioned. At a quick glance at the issue it seems to me the issue is worthy of continued study but the evidence of harm is not conclusive yet (the FDA, European Food Safety Authority and Japan have examined the issue and find current levels safe). However, I am concerned about the general increase it chemicals in our food supply, ground water… so I think this is an area that needs constant monitoring and increases in funding for public health studies. Obviously the industries effected have an interest in maintaining the status quo and influencing government to concur. Those pressures have to be offset by proper government research and oversight. Which is not easy to maintain.

I personally want to err on the side of safety even if that increases costs. But making those tradeoffs – costs versus safety are complicated for an entire economy. Examining the existing evidence to see if there is a high likelihood of danger is not that tricky (that seems to be no, right now, for Bisphenol A). But determining whether the likelihood of danger is too high in reality (not that has been proved yet) is much more difficult. Even deciding what things to devote resources to for further study is quite challenging.

Links: Bisphenol A Exposure In Utero Disrupts Early Oogenesis in the Mouse – Opinion of the Scientific Panel AFC related to 2,2-BIS(4-HYDROXYPHENYL)PROPANE – EPA on Bisphenol A. – ‘Inherently toxic’ chemical faces its future – European Safety Review – No Risk from Bisphenol A Exposure – Bisphenol A industry web site

Climate Change Impacts, Adaptation and Vulnerability

Climate Change 2007: Climate Change Impacts, Adaptation and Vulnerability by the Intergovernmental Panel on Climate Change – summary (pdf) [the broken link has been removed]

Related articles: International report details impact of global warming [the broken link has been removed] – Climate change around the world – U.S., China Got Climate Warnings Toned Down – Permanent drought predicted for Southwest [paywall added so the broken link has been removed]