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.

Superbugs – Deadly Bacteria Take Hold

Superbugs by Jerome Groopman, New Yorker:

“My basic premise,” Wetherbee said, “is that you take a capable microÃ¶rganism like Klebsiella and you put it through the gruelling test of being exposed to a broad spectrum of antibiotics and it will eventually defeat your efforts, as this one did.” Although Tisch Hospital has not had another outbreak, the bacteria appeared soon after at several hospitals in Brooklyn and one in Queens. When I spoke to infectious-disease experts this spring, I was told that the resistant Klebsiella had also appeared at Mt. Sinai Medical Center, in Manhattan, and in hospitals in New Jersey, Pennsylvania, Cleveland, and St. Louis.
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Unlike resistant forms of Klebsiella and other gram-negative bacteria, however, MRSA can be treated. “There are about a dozen new antibiotics coming on the market in the next couple of years,” Moellering noted. “But there are no good drugs coming along for these gram-negatives.” Klebsiella and similarly classified bacteria, including Acinetobacter, Enterobacter, and Pseudomonas, have an extra cellular envelope that MRSA lacks, and that hampers the entry of large molecules like antibiotic drugs. “The Klebsiella that caused particular trouble in New York are spreading out,” Moellering told me. “They have very high mortality rates. They are sort of the doomsday-scenario bugs.”

Great article. Related: Bacteria Survive On All Antibiotic Diet – Bacteria Can Transfer Genes to Other Bacteria – New Yorker on CERN’s Large Hadron Collider – posts on health related topics

Dolphin Kick Gives Swimmers Edge

photo of Michael Phelps diving

Dolphin Kick Gives Swimmers Edge

Rajat Mittal, a professor of mechanical and aerospace engineering at the George Washington University, was studying dolphins for the U.S. Navy five years ago. “We were asked to understand how fish swim so efficiently,” Mittal says, “and it seemed like a natural extension to apply this to human swimming.”
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They decided to “essentially compare these swimmers to the dolphin, assuming that the dolphin is the ultimate swimmer,” Mittal says. “And the thing that we found is that Michael [Phelps] is able to use his body in a way that is very, very different from the other athletes, and also seems to be much closer to dolphins than we have seen for any other swimmer.”

The dolphin kick first hit Olympic swimming big-time 20 years ago, after Harvard backstroker David Berkoff figured out something fundamental. “It seemed pretty obvious to me that kicking underwater seemed to be a lot faster than swimming on the surface,” Berkoff says.

That’s because there’s turbulence and air on the surface of the water, and they create resistance. The “Berkoff Blastoff,” as it was called, was used at the start and after turns, with long stretches of that underwater undulating kick.

Follow the link for a video of Michael Phelps demonstrating the technique and more interesting details. Photo by A. Dawson shows Michael Phelps diving into the water at the 2008 U.S. Olympic Swimming Trials.

Buckminster Fuller at the Whitney

The Whitney in NYC has a Buckminster Fuller Exhibit through September 15, 2008.

One of the great American visionaries of the twentieth century, R. Buckminster Fuller (1895-1983) endeavored to see what he, a single individual, might do to benefit the largest segment of humanity while consuming the minimum of the earth’s resources. Doing “more with less” was Fuller’s credo.
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Fuller’s innovative theories and designs addressed fields ranging from architecture, the visual arts, and literature to mathematics, engineering, and sustainability. He refused to treat these diverse spheres as specialized areas of investigation because it inhibited his ability to think intuitively, independently, and, in his words, “comprehensively.”
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The results of more than five decades of Fuller’s integrated approach toward the design and technology of housing, transportation, cartography, and communication are displayed here, much of it for the first time. This exhibition offers a fresh look at Fuller’s life’s work for everyone who shares his sense of urgency about homelessness, poverty, diminishing natural resources, and the future of our planet.

Engineering TV

Engineering TV offers some nice videos. The site needs more content and some better usability (almost no webcasts are returned on clicking the tags – though they can be found by searching, videos play with sound automatically (without user approval), the ad sounds are way too loud…) but it is another site that might provide some interesting webcasts. I am still most hopeful about SciVee (based on the tie to PLoS) – though the progress has been slow so far.

USA Broadband is Slow. Really Slow.

Surprise, surprise: U.S. broadband is slow. Really slow.

The U.S. comes in 15th on a worldwide scale, far behind the leaders Japan, South Korea and Finland.
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A file that takes four minutes to download in South Korea would take nearly an hour and a half to download in the U.S. using the average bandwidth. Japanese users leaves U.S. users behind with an eye-popping 63.60 Mb/s download link. This means that Japanese can download an entire movie in just two minutes, as opposed to two hours or more here in the U.S. Just in case you are wondering: No, Japanese users do not pay more for their broadband connections. In fact, U.S. broadband cost is among the highest in the world.

Japan dominates international broadband speed with a median download speed of approximately 63 Mb/s, more than enough to stream DVD-quality video with surround audio in real time. Next on the list is South Korea where download speeds achieve an average of 49.50 Mb/s. Finland and France follow with 21.70 Mb/s and 17.60 Mb/s, respectively. Canada ranked eighth with an average download speed of 7.60 Mb/s. The U.S. came in 15th with 2.35 Mb/s.

I see this as an economic issue. Countries that have provided an investment in internet infrastructure to provide broadband to the home at reasonable prices will be rewarded.

How Humans Got So Smart

Cooking and Cognition: How Humans Got So Smart

For a long time, we were pretty dumb. Humans did little but make “the same very boring stone tools for almost 2 million years,” he said. Then, only about 150,000 years ago, a different type of spurt happened — our big brains suddenly got smart. We started innovating. We tried different materials, such as bone, and invented many new tools, including needles for beadwork. Responding to, presumably, our first abstract thoughts, we started creating art and maybe even religion.

To understand what caused the cognitive spurt, Khaitovich and colleagues examined chemical brain processes known to have changed in the past 200,000 years. Comparing apes and humans, they found the most robust differences were for processes involved in energy metabolism.

The finding suggests that increased access to calories spurred our cognitive advances, said Khaitovich, carefully adding that definitive claims of causation are premature.

Nice example of scientific discovery in action. The direct link from cooking to brain development is far from proven but it is interesting. I also like “the same very boring stone tools for almost 2 million years” – maybe that is because I am too cynical (but while evolution is amazing – sometimes it is amazing how slow progress is).

Lighting in Slow Motion

Video deleted

The videos provides a super slow motion lighting strike. A separate lighting related item, from NASA: Gigantic Jets:

They are extremely rare but tremendously powerful. Gigantic jets are a newly discovered type of lightning discharge between some thunderstorms and the Earth’s ionosphere high above them. Pictured above is one such jet caught by accident by a meteor camera in Oklahoma, USA. The gigantic jet, at the lower left, traversed perhaps 70 kilometers in just under one second.

Invisibility Cloak Closer

Invisibility shields one step closer with new metamaterials that bend light backwards

Applications for a metamaterial entail altering how light normally behaves. In the case of invisibility cloaks or shields, the material would need to curve light waves completely around the object like a river flowing around a rock. For optical microscopes to discern individual, living viruses or DNA molecules, the resolution of the microscope must be smaller than the wavelength of light.

The common thread in such metamaterials is negative refraction. In contrast, all materials found in nature have a positive refractive index, a measure of how much electromagnetic waves are bent when moving from one medium to another.

In a classic illustration of how refraction works, the submerged part of a pole inserted into water will appear as if it is bent up towards the water’s surface. If water exhibited negative refraction, the submerged portion of the pole would instead appear to jut out from the water’s surface.
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For a metamaterial to achieve negative refraction, its structural array must be smaller than the electromagnetic wavelength being used. Not surprisingly, there has been more success in manipulating wavelengths in the longer microwave band, which can measure 1 millimeter up to 30 centimeters long.

Compressor-free Refrigerator

Compressor-free refrigerator may loom in the future

Refrigerators and other cooling devices may one day lose their compressors and coils of piping and become solid state, according to Penn State researchers who are investigating electrically induced heat effects of some ferroelectric polymers.

“This is the first step in the development of an electric field refrigeration unit,” says Qiming Zhang, distinguished professor of electrical engineering. “For the future, we can envision a flat panel refrigerator. No more coils, no more compressors, just solid polymer with appropriate heat exchangers.”
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Zhang’s approach uses the change form disorganized to organized that occurs in some polarpolymers when placed in an electric field. The natural state of these materials is disorganized with the various molecules randomly positioned. When electricity is applied, the molecules become highly ordered and the material gives off heat and becomes colder. When the electricity is turned off, the material reverts to its disordered state and absorbs heat.

Photos of Parfrey’s Glen, Wisconsin

photo of Yellow Flower in Parfreys Glen

See more photos from my visit to Parfrey’s Glen Natural Area in Wisconsin, about an hour outside of Madison. It really was amazingly beautiful – the pictures do not do it justice. The Parfrey’s Glen trail is under a mile but well worth visiting. If you want to hike more try the Ice Age National Scenic Trail or nearby Devil’s Lake State Park. The top photo is of me (John Hunter) at nearby Durwood’s Glen. The yellow flower is from Parfrey’s Glen.

Photo of yellow flower by John Hunter is available for use: Creative Commons Attribution-Share Alike (see requirements for use).

Parfrey’s Glen is Wisconsin’s first State Natural Area, is a spectacular gorge deeply incised into the sandstone conglomerate of the south flank of the Baraboo Hills. The exposed Cambrian strata provide excellent opportunities for geological interpretation. The walls of the glen – a Scottish word for a narrow, rocky ravine – are sandstone with embedded pebbles and boulders of quartzite.