Category Archives: Students

Items for students and others, interested in learning about science and engineering and the application of science in our lives. We post many of the general interest items here.

Brain Development

Making the Mind, Why we’ve misunderstood the nature-nuture debate by Gary Marcus

The mapping between genes and behavior is made even more complex by the fact that few if any neural circuits operate entirely autonomously. Except perhaps in the case of reflexes, most behaviors are the product of multiple interacting systems. In a complex animal like a mammal or a bird, virtually every action depends on a coming together of systems for perception, attention, motivation, and so forth. Whether or not a pigeon pecks a lever to get a pellet depends on whether it is hungry, whether it is tired, whether there is anything else more interesting around, and so forth. Furthermore, even within a single system, genes rarely participate directly “on-line,” in part because they are just too slow. Genes do seem to play an active, major role in “off-line” processing, such as consolidation of long-term memory—which can even happen during sleep—but when it comes to rapid on-line decision-making, genes, which work on a time scale of seconds or minutes, turn over the reins to neurons, which act on a scale of hundredths of a second. The chief contribution of genes comes in advance, in laying down and adjusting neural circuitry, not in the moment-by-moment running of the nervous system. Genes build neural structures—not behavior.

An interesting read on brain development. This is another topic I find very interesting.

Science Explained: What The Heck is a Virus?

What The Heck is a Virus? [removed broken link]

A virus is not strictly alive.. nor is it strictly dead… A virus has some fundamental information (genes made of DNA or RNA) which allows it to make copies of itself. However, the virus must be inside a living cell of some kind before the information can be used. In fact, the information won’t be made available unless the virus enters a living cell. It is this entrance of a virus into a cell which is called a viral infection. Too, the virus is very, very small relative to the size of a living cell. Therefore, the information the virus can carry is actually not enough to allow it to make copies (replicate). The virus uses the cell’s machinery and some of the cell’s enzymes to generate virus parts which are later assembled into thousands of new, mature, infectious virus which can leave the cell to infect other cells.

Bigger Impact: 15 to 18 mpg or 50 to 100 mpg?

This is a pretty counter-intuitive statement, I believe:

You save more fuel switching from a 15 to 18 mpg car than switching from a 50 to 100 mpg car.

But some simple math shows it is true. If you drive 10,000 miles you would use: 667 gallons, 556 gallons, 200 gallons and 100 gallons. Amazing. I must admit, when I first read the quote I thought that it must be an wrong. But there is the math. You save 111 gallons improving from 15 mpg to 18 mpg and just 100 improving from 50 to 100 mpg. Other than those of you who automatically guess that whatever seems wrong must be the answer when you see a title like this I can’t believe anyone thinks 15 to 18 mpg is the change that has the bigger impact. It is great how a little understanding of math can help you see the errors in your initial beliefs. Via: 18 Is Enough.

It also illustrates that the way the data is presented makes a difference. You can also view 100 mpg as 1/100 gallon per mile, 2/100 gallons per mile, 5.6/100 gpm and 6.7 gpm. That way most everyone sees that the 6.7 to 5.6 gpm saves more fuel than 2 to 1 gpm does. Mathematics and scientific thinking are great – if you are willing to think you can learn to better understand the world we live in every day.

Carnegie Mellon Robotics Academy

The Carnegie Mellon Robotics Academy is designed to use robotics to excite children about science and technology and to help create a more technologically literate society. This seems like quite a nice idea to me.

When students design and build robots they study math, science, engineering, and physics. Robotics Education is the “Premier Integrator” in education today. Students are immersed in geometry, trigonometry, electronics, programming, computer control and mechanics while using industry standard software and hardware. They learn to compromise when working in teams. They learn the importance of time management and resource allocation. They are introduced to the concept of systems and systems analysis.
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Currently there are over 80 companies in the Southwestern Pennsylvania region that design, sell, or service robots. Carnegie Mellon University, the governing body of the NREC, has a world-renowned reputation for robotics. NASA, one of the funders of the consortium, has an unparalleled commitment to education. Pittsburgh and The National Robotics Engineering Consortium have all the components necessary to become the world leader in Robotics Education.

Why is it important? Most of the technologies that we depend on daily were developed in the last ten years. The only constant is change, and change is exponential in the digitally driven world in which we find ourselves. If you believe as we do that it is the scientists and technologists that will have the greatest impact on the quality of your life in the future, then you will find the following statistics alarming.

Great Physics Webcast Lectures

One great example of MIT’s Open Course Ware initiative is Physics I: Classical Mechanics. This course features lecture notes, problem sets with solutions, exams with solutions, links to related resources, and a complete set of videotaped lectures. The 35 video lectures by Professor Lewin, were recorded on the MIT campus during the Fall of 1999. These are some great lectures by a entertainer and educator. Some lecture topics: Newton’s Laws, Momentum – Conservation of Momentum – Center of Mass, Doppler Effect – Binary Stars – Neutron Stars and Black Holes, The Wonderful Quantum World – Breakdown of Classical Mechanics. What a wonderful web it is.

Giant Rats

Giant rat found in ‘lost world

The trip was the second time that CI had visited the Foja Mountains, part of the Mamberamo Basin, the largest pristine tropical forest in the Asia Pacific region. In 2005, the area was dubbed a “lost world” after scientists discovered dozens of new plants and animals in the dense jungle.
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the most surprising finds of the trip were the two new species of mammal – the Cercarteus pygmy possum and Mallomys giant rat. “The giant rat is about five times the size of a typical city rat,” said Kristofer Helgen, a scientist with the Smithsonian Institution in Washington, D.C. “With no fear of humans, it apparently came into the camp several times during the trip.”

Expensive Ink

$8,000-per-gallon printer ink leads to antitrust lawsuit

For most printer companies, ink is the bread and butter of their business. The price of ink for HP ink-jet printers can be as much as $8,000 per gallon, a figure that makes gas-pump price gouging look tame. HP is currently the dominant company in the printing market, and a considerable portion of the company’s profits come from ink.

The printer makers have been waging an all-out war against third-party vendors that sell replacement cartridges at a fraction of the price. The tactics employed by the printer makers to maintain monopoly control over ink distribution for their printing products have become increasingly aggressive. In the past, we have seen HP, Epson, Lenovo and other companies attempt to use patents and even the Digital Millennium Copyright Act in their efforts to crush third-party ink distributors.

The companies have also turned to using the ink equivalent of DRM, the use of microchips embedded in ink cartridges that work with a corresponding technical mechanism in the printer that blocks the use of unauthorized third-party ink.

Tip – by a printer from a company that doesn’t rip you off as much for ink: The Kodak 5300 All-in-One Printer, which uses ultra low-priced ink to help you save up to 50 percent. Kodak has made the strategic decision to compete with the entrenched printing companies by not ripping off customers as much. Ok I am not really sure how this really fits one this blog but I want to put it here so I will 🙂

Handcrafted Chromosomes

Synthetic DNA on the Brink of Yielding New Life Forms

Scientists in Maryland have already built the world’s first entirely handcrafted chromosome — a large looping strand of DNA made from scratch in a laboratory, containing all the instructions a microbe needs to live and reproduce.

In the coming year, they hope to transplant it into a cell, where it is expected to “boot itself up,” like software downloaded from the Internet, and cajole the waiting cell to do its bidding. And while the first synthetic chromosome is a plagiarized version of a natural one, others that code for life forms that have never existed before are already under construction.
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LS9 Inc., a company in San Carlos, Calif., is already using E. coli bacteria that have been reprogrammed with synthetic DNA to produce a fuel alternative from a diet of corn syrup and sugar cane. So efficient are the bugs’ synthetic metabolisms that LS9 predicts it will be able to sell the fuel for just $1.25 a gallon.

At a DuPont plant in Tennessee, other semi-synthetic bacteria are living on cornstarch and making the chemical 1,3 propanediol, or PDO. Millions of pounds of the stuff are being spun and woven into high-tech fabrics (DuPont’s chief executive wears a pinstripe suit made of it), putting the bug-begotten chemical on track to become the first $1 billion biotech product that is not a pharmaceutical.

Engineers at DuPont studied blueprints of E. coli’s metabolism and used synthetic DNA to help the bacteria make PDO far more efficiently than could have been done with ordinary genetic engineering.

Related: Life-patents – Open-Source Biotech

The State of Physics

The Problem with Physics by Peter Woit

Physics has become obsessed with strings, branes and multiple dimensions, yet the big questions remain fundamentally unanswered. Has the time come to admit these wild conjectures have failed, and move on?
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Fundamental physics now finds itself in a historically unprecedented situation. The multi-decade dominance of string theory, along with its extremely speculative research into the implications of exotic scenarios far removed from any hope of testability, has changed the subject in dramatic and fundamental ways.

What used to be considered part of the dubious fringes of science has now become institutionalised within the mainstream. In physicist Lee Smolin’s recent book, The Trouble With Physics, he characterises the current sociology of the field as dominated by ‘groupthink’, with too few physicists willing to admit how far off the tracks things have gone. The nearly infinite complexity of string theory, M-theory, branes, higher dimensions and the multiverse has led to a vast number of possible challenging calculations for people to do to keep themselves busy, all embedded in a mathematical structure far too poorly understood to ever lead to definitive, falsifiable predictions.

The problems of the Standard Model that faced my colleague and I a quarter of a century ago continue to inspire new generations of young theorists to devote their lives to work that might some day lead to real progress. But these problems remain extremely difficult ones, and we have little in the way of promising ideas, with far too much effort going into the evasion of difficulties and the pursuit of the chimera of unification through ever more complex higher dimensional constructions inspired by string theory.

Superfluid Helium

Once helium is cooled to within 2 degrees above absolute zero helium becomes a superfluid. At that point is has zero viscosity and can do things like rise out of a container – scaling the walls. Graphic from Wikipedia on Superfluid:

Helium II will “creep” along surfaces in order to find its own level – after a short while, the levels in the two containers will equalize. The Rollin film also covers the interior of the larger container; if it were not sealed, the helium II would creep out and escape.

More interesting superfluid traits:

The superfluid component has zero viscosity, zero entropy, and infinite thermal conductivity. (It is thus impossible to set up a temperature gradient in a superfluid, much as it is impossible to set up a voltage difference in a superconductor.) One of the most spectacular results of these properties is known as the thermomechanical or “fountain effect”. If a capillary tube is placed into a bath of superfluid helium and then heated, even by shining a light on it, the superfluid helium will flow up through the tube and out the top as a result of the Clausius-Clapeyron relation. A second unusual effect is that superfluid helium can form a layer, a single atom thick, up the sides of any container in which it is placed.