Babbage Difference Engine In Lego
Posted on March 31, 2008 Comments (1)
Building A Calculating Machine Using Lego Pieces by Andrew Carol
In the mid-19th century, people began to design machines to automate this error prone process. Many machines of various designs were eventually built but, the most advanced and famous of these was not. The Babbage Difference Engine.
Because of engineering issues as well as political and personal conflict the Babbage Difference engines construction had to wait until 1991 when the Science Museum in London decided to build the Babbage Difference Engine No.2 for an exhibit on the history of computers.
Babbage’s design could evaluate 7th order polynomials to 31 digits of accuracy. I set out to build a working Difference Engine using standard LEGO parts which could compute 2nd or 3rd order polynomials to 3 or 4 digits. I have built two generations of Difference Engines and am designing the third version now.
Related: Rubick’s Cube Solving Lego Mindstorms Robot – Lego Autopilot Project Update – Open Source for LEGO Mindstorms – Donald Knuth, Computer Scientist
Don’t Eat What Doesn’t Rot
Posted on March 31, 2008 Comments (3)
Here is a nice interview of Michael Pollan by Amy Goodman – Don’t Eat Anything That Doesn’t Rot:
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if you look at the layout of the average supermarket, the fresh whole foods are always on the edge. So you get produce and meat and fish and dairy products. And those are the foods that, you know, your grandmother would recognize as foods. They haven’t changed that much. All the processed foods, the really bad stuff that is going to get you in trouble with all the refined grain and the additives and the high-fructose corn syrup, those are all in the middle. And so, if you stay out of the middle and get most of your food on the edges, you’re going to do a lot better.
Related: Research on Why Healthy Living Leads to Longer Life – Eat food. Not too much. Mostly plants. – Raised Without Antibiotics – Another Strike Against Soda – Energy Efficiency of Digestion
Warning on Two Cholesterol Drugs
Posted on March 30, 2008 Comments (3)
Journal Issues Warning on Two Cholesterol Drugs
The journal’s conclusion came as doctors at a major cardiology conference in Chicago saw for the first time the full results of a two-year clinical trial that showed that the drugs failed to slow, and might have even sped up, the growth of fatty plaques in the arteries. Growth of those plaques is closely correlated with heart attacks and strokes.
Merck and Schering-Plough, the companies that make Vytorin and Zetia, said on Sunday that despite the results of the trial, they would continue to promote their medicines as first-line treatments for high cholesterol.
Related: Drug Price Crisis – New Questions on Treating Cholesterol – Lifestyle Drugs and Risk
Ethanol Scam
Posted on March 30, 2008 Comments (0)
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Meanwhile, by diverting grain and oilseed crops from dinner plates to fuel tanks, biofuels are jacking up world food prices and endangering the hungry. The grain it takes to fill an SUV tank with ethanol could feed a person for a year. Harvests are being plucked to fuel our cars instead of ourselves. The U.N.’s World Food Program says it needs $500 million in additional funding and supplies, calling the rising costs for food nothing less than a global emergency. Soaring corn prices have sparked tortilla riots in Mexico City, and skyrocketing flour prices have destabilized Pakistan, which wasn’t exactly tranquil when flour was affordable.
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One groundbreaking new study in Science concluded that when this deforestation effect is taken into account, corn ethanol and soy biodiesel produce about twice the emissions of gasoline. Sugarcane ethanol is much cleaner, and biofuels created from waste products that don’t gobble up land have real potential, but even cellulosic ethanol increases overall emissions when its plant source is grown on good cropland. “People don’t want to believe renewable fuels could be bad,” says the lead author, Tim Searchinger, a Princeton scholar and former Environmental Defense attorney. “But when you realize we’re tearing down rain forests that store loads of carbon to grow crops that store much less carbon, it becomes obvious.”
Related: Is Ethanol a Science Based Solution or Special Interest Payoff – Biofuels use Could Worsen Global Warming – Peak Soil – Converting Emissions to Biofuels – Geothermal Power in Alaska
Appetite for Destruction
Posted on March 29, 2008 Comments (1)

Appetite for Destruction (link broken, so I removed it) by Eric R. Olson:
Global climate change, which is pushing temperatures higher, has altered the beetle’s natural life cycle. Now the insect threatens one of the world’s largest forest systems: Canada’s boreal forest, a 600-mile-wide band of pine woodlands that stretches from the Yukon in Alaska all the way to Newfoundland on the East Coast.
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The source of all this destruction is an insect not much bigger than a grain of rice. A native of North America, the pine beetle does its damage by burrowing beneath the bark and feeding on the living tissue of the tree called the phloem. This tissue is composed of long tubes that transport nutrients from root to limb, and once it is destroyed, the tree can no longer survive.
In the past, cold snaps — quick drops in temperature in the spring and fall — have kept beetle populations in check. Although the insects can survive temperatures as low as minus 35 degrees Fahrenheit in the winter, it takes time for their bodies to accumulate enough glycol, the same ingredient found in antifreeze, to survive such frigid temperatures.
Photo: Mountain Pine Beetle (Dendroctonus Ponderosae) under a scanning electron microscope. [Credit: Leslie Manning/Canadian Forest Service]
Related: Rain Forests – Deforestation and Global Warming – Bed Bugs, Science and the Media
Thompson and Tits share 2008 Abel Prize (Math)
Posted on March 28, 2008 Comments (0)
Thompson and Tits share the Abel Prize for 2008
In 1963, Thompson and Walter Feit proved that all nonabelian finite simple groups were of even order, work for which they both won the Frank Nelson Cole Prize in Algebra from the AMS in 1965. Thompson also won a Fields Medal in 1970. In the Abel citation for Tits, the committee writes that “Tits created a new and highly influential vision of groups as geometric objects. He introduced what is now known as a Tits building, which encodes in geometric terms the algebraic structure of linear groups.” The committee noted the link between the two winners’ work: “Tits’s geometric approach was essential in the study and realization of the sporadic groups, including the Monster.” Tits received the Grand Prix of the French Academy of Sciences in 1976, and the Wolf Prize in Mathematics in 1993.
The Abel Prize is awarded by the Norwegian Academy of Science and Letters for outstanding scientific work in the field of mathematics. The prize amount is 6,000,000 Norwegian kroner (over US$1,000,000).
Related: Professor Marcus du Sautoy on Thompson and Tits – Math’s Architect of Beauty – 2007 Nobel Prize in Physics – Poincaré Conjecture
Squid Materials Engineering
Posted on March 28, 2008 Comments (0)
Scientists find that squid beak is both hard and soft
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The key to the squid beak lies in the gradations of stiffness. The tip is extremely stiff, yet the base is 100 times more compliant, allowing it to blend with surrounding tissue. However, this only works when the base of the beak is wet. After it dries out, the base becomes similarly stiff as the already desiccated beak tip.
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“You can imagine the problems you’d encounter if you attached a knife blade to a block of Jell-o and tried to use that blade for cutting. The blade would cut through the Jell-o at least as much as the targeted object. In the case of the squid beak, nature takes care of the problem by changing the beak composition progressively, rather than abruptly, so that its tip can pierce prey without harming the squid in the process. It’s a truly fascinating design!”
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“If we could reproduce the property gradients that we find in squid beak, it would open new possibilities for joining materials,” explained Zok. “For example, if you graded an adhesive to make its properties match one material on one side and the other material on the other side, you could potentially form a much more robust bond,” he said. “This could really revolutionize the way engineers think about attaching materials together.”
Related: Deep-Sea Giant Squid – Self Healing Plastic – Sea Slug Photo Gallery
Tags: California,Engineering,materials engineering,ocean,Research
Propeller Innovation by Engineering Students
Posted on March 28, 2008 Comments (0)
Innovation propels students’ careers
Most propellers have a body encasing the motor. There’s air inside, which can cause the body to collapse when submerged in oceanic depths. The casing also creates drag, slowing the machine down and making it difficult to move backward.
But Shea, along with Brian Claus, Peter Crocker and Toren Gustafson, devised a way to build the motor in the casing that surrounds the propeller blades. The parts are assembled in a ring shape then encased in epoxy, making the motor waterproof. The propeller is fastened inside the ring, allowing it to easily move forward or backward.
Related: PhD Student Speeds up Broadband by 200 times – Singapore Students Engineer New Products – Concentrating Solar Collector wins UW-Madison Engineering Innovation Award
Solar Energy: Economics, Government and Technology
Posted on March 27, 2008 Comments (10)
An American Solar Opportunity Gets Shipped Abroad
They’ll be installed in Europe. In Asia. And maybe even in America too, one day. Why not now? Because AES wants to sow its solar seeds in only those countries that offer the most “attractive tariffs.” That eliminates the US from the list of potentials, immediately. And it gives countries like Germany, Spain, Italy and South Korea the clear advantage. They all have can’t-beat national incentives for solar developers.
It’s one of the sad facts of Washington’s incoherent clean energy policy these days. How can a country lure in clean energy projects when there are far more appealing offers elsewhere?
Government actions impact economic decisions. It will likely take more than 10 years to have good data on what government investments pay off in the energy sector. But I would say it is a pretty good bet to invest in technology such as: solar, geothermal, wind… Countries that create global centers of excellence in these areas are likely to benefit greatly. The only question I think is that many countries are smart enough to see the benefits and so likely many countries will try.
Any time many actors pursue the same economic strategy there is the risk that the payoff is diluted with so many others having done the same thing. Still the reason so many countries have adopted the strategy of developing centers of excellence in science, engineering and technology is that it is such a good idea. The USA has a problem in that we are spending more than we produce on luxuries today so there is much less available to invest compared to other countries (and compared to 40 years ago).
Related: Global Installed Capacity of Wind Power – Invest in Science for a Strong Economy – Science, Engineering and the Future of the American Economy – China challenges scientific research dominance of USA, Europe and Japan – Green Energy in Canada
Tags: centers of excellence,economy,Energy,government,solar energy
Secrets of Spider Silk’s Strength
Posted on March 27, 2008 Comments (0)
Secrets of Spider Silk’s Strength
This structure makes the lightweight natural material as strong as steel, even though the “glue” of hydrogen bonds that hold spider silk together at the molecular level is 100 to 1,000 times weaker than the powerful glue of steel’s metallic bonds or even Kevlar’s covalent bonds.
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“Using only one or two hydrogen bonds in building a protein provides no or very little mechanical resistance, because the bonds are very weak and break almost without provocation,” said Buehler, the Esther and Harold E. Edgerton Assistant Professor in the Department of Civil and Environmental Engineering. “But using three or four bonds leads to a resistance that actually exceeds that of many metals. Using more than four bonds leads to a much-reduced resistance. The strength is maximized at three or four bonds.”
Related:Why a spider hanging from a thread does not rotate – 60 Acre (24 hectare) Spider Web
Mutation Rate and Evolution
Posted on March 26, 2008 Comments (0)
Stop the Mutants! by Olivia Judson
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Actually stopping mutations is a physical impossibility – hence the need for a magic wand. But if they were to stop, so would raw invention. But evolution would not. Not for a long time.
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And sometimes natural selection actively promotes the persistence of genetic variation. This can happen when there’s an advantage to having genes that are rare. Among guppies, for example, males with rare color patterns are much more likely to survive than those with common color patterns, presumably because predators get good at spotting the patterns they encounter often. In such situations, the rare type does well, begins to become common – and then becomes the victim of its own success and starts to do badly. In situations like this, the frequencies of different genes can rise and fall, cycling indefinitely.
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Among lifestyles that promote genetic diversity, far and away the most important is sex. Sex shuffles up genes, continually producing new gene combinations. (An important difference between sex and mutation is that sex can only create genetic novelty if it already exists in the population. If everyone is genetically identical, sex will have no effect.) Sex also – and this is important – decouples the fates of genes from one another.
Good stuff. Related: Evolution is Fundamental to Science – Evolution In Action – Evolution in Darwin’s Finches

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