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.

Patenting Life – a Bad Idea

Patenting Life by Michael Crichton (new book = Next, also The Andromeda Strain, Jurassic Park…):

Gene patents are now used to halt research, prevent medical testing and keep vital information from you and your doctor. Gene patents slow the pace of medical advance on deadly diseases. And they raise costs exorbitantly: a test for breast cancer that could be done for $1,000 now costs $3,000.

Why? Because the holder of the gene patent can charge whatever he wants, and does. Couldn’t somebody make a cheaper test? Sure, but the patent holder blocks any competitor’s test. He owns the gene. Nobody else can test for it. In fact, you can’t even donate your own breast cancer gene to another scientist without permission. The gene may exist in your body, but it’s now private property.

This bizarre situation has come to pass because of a mistake by an underfinanced and understaffed government agency. The United States Patent Office misinterpreted previous Supreme Court rulings and some years ago began — to the surprise of everyone, including scientists decoding the genome — to issue patents on genes.

This has to be fixed, and here is one way that might help: Continue reading →

Water in Earth’s Deep Mantle

3-D seismic model of vast water reservoir revealed:

n analyzing the data, Wysession first saw large patterns associated with known areas where the ocean floor is sinking down into the earth. Beneath Asia, the fallen Pacific sea floor piles up at the base of the mantle. Right above that he observed an “incredibly highly attenuating region, that is both very damping and slightly slow,” he said. “Water slows the speed of waves a little. Lots of damping and a little slowing match the predictions for water very well.”

Previous predictions calculated that a cold ocean slab sinking into the earth at 1,200 to 1,4000 kilometers beneath the surface would release water in the rock that would escape the rock and rise up to a region above it, but this was never previously observed.

“That is exactly what we show here, the exact depth and high attenuation amounts right above it,” Wysession said. “I call it the Beijing anomaly. Water inside the rock goes down with the sinking slab and it’s quite cold, but it heats up the deeper it goes, and the rock eventually becomes unstable and loses its water. The water then rises up into the overlying region, which becomes saturated with water.

“If you combine the volume of this anomaly with the fact that the rock can hold up to about 0.1 percent of water, that works out to be about an Arctic Ocean’s worth of water.”

Skin Bacteria

Close Look at Human Arm Finds Host of Microbes:

“The skin is home to a virtual zoo,” said Blaser, a microbiologist who last week published online the first molecular analysis of the bacteria living on one small patch of human skin. “We’re just beginning to explore it.” The analysis revealed that human skin is populated by a diverse assortment of bacteria, including many previously unknown species, offering the first detailed peek at this potentially crucial ecosystem.

The work is part of a broader effort by a small coterie of scientists to better understand the microbial world that populates the human body. Virtually every orifice and the digestive tract are swarming with bacteria, fungi and other microbes. By some estimates, only one out of every 10 cells in the body is human.
…
Blaser’s team swabbed an area of skin about the size of silver dollar on the right and left forearms of three healthy men and three healthy women. They then used sophisticated molecular techniques to amplify and analyze fragments of bacterial DNA captured by the swabs. The analysis revealed 182 species, the researchers reported. Of those, 30 had never been seen. They identified an additional 65 species when they sampled four of the volunteers eight to 10 months later, including 14 new species.

Continue reading →

DNA Transcription Webcast

DNA Transcription webcast – via How DNA transcription works

Produced by The World Wide Web Instructional Committee (WWWIC) at North Dakota State University faculty dedicated to developing internet-based educational software. Funded by NSF and the US Department of Education.

Mini Helicopter Masters Insect Navigation Trick

Mini helicopter masters insect navigation trick:

A miniature robotic helicopter has revealed a simple yet effective visual trick that lets insects fly so adeptly without sophisticated avionics.
…
As insects fly forwards the ground beneath them sweeps backwards through their field of view. This “optical flow” is thought to provide crucial cues about speed and height. For example, the higher an insect’s altitude, the slower the optical flow; the faster it flies, the faster the optical flow.

Previous experiments involving bees suggest that optical flow is crucial to landing. Maintaining a constant optical flow while descending should provide a constant height-to-groundspeed ratio, which makes a bee slowdown as it approaches the ground. Distorting this optical flow can cause them to crash land instead.

Biomedical Engineering Opinion

An insight into biomedical engineering

Nevertheless, the strict regulatory procedures that must be adhered to in biomedical engineering can be frustrating and feel like a barrier to innovation, even though engineers in this field are often working at the leading edge of technology. Colin Hunsley says: “Anything new has to be shown to be better than what is currently available. A modern hip replacement, for example, is expected to last for 15 years or more; even with thorough testing via the formal clinical trials process, it can be hard to prove conclusively that a new development is significantly better.

The take-up of new products and techniques also depends to some extent on the way the market operates. In the UK, for instance, the National Health Service (NHS) funds most healthcare, whereas the USA market is driven by private medical insurance. With the budgeting structure of the NHS, it can be difficult to justify the adoption in one department of a more expensive treatment, even if it could lead to significant long-term savings for another department. This illustrates why it is important that biomedical engineers understand the market in which they operate.

Mystery Ailment Strikes Honeybees

A mysterious illness is killing tens of thousands of honeybee colonies across the country, threatening honey production, the livelihood of beekeepers and possibly crops that need bees for pollination. Researchers are scrambling to find the cause of the ailment, called Colony Collapse Disorder.
…
The country’s bee population had already been shocked in recent years by a tiny, parasitic bug called the varroa mite, which has destroyed more than half of some beekeepers’ hives and devastated most wild honeybee populations.

Along with being producers of honey, commercial bee colonies are important to agriculture as pollinators, along with some birds, bats and other insects. A recent report by the National Research Council noted that in order to bear fruit, three-quarters of all flowering plants _ including most food crops and some that provide fiber, drugs and fuel _ rely on pollinators for fertilization.

Schoofs Prize for Creativity 2007

Single-handed fishing kit reels in first place in invention competition:

Brian “Sunya” Nimityongskul got the idea for a system for one-armed fishing while recovering from shoulder surgery last summer. “I wanted to be fishing and not sitting at home,” he says. “Being an engineer, I decided I’d do something about it.” He worked on it during his free time, doing the design and machining himself

No Sleep, No New Brain Cells

No sleep means no new brain cells

The researchers compared animals who were deprived of sleep for 72 hours with others who were not. They found those who missed out on rest had higher levels of the stress hormone corticosterone. It would be interesting to see if partial sleep deprivation – getting a little bit less sleep every night that you need – had the same effect

They also produced significantly fewer new brain cells in a particular region of the hippocampus. When the animals’ corticosterone levels were kept at a constant level, the reduction in cell proliferation was abolished. The results suggest that elevated stress hormone levels resulting from sleep deprivation could explain the reduction in cell production in the adult brain.

Sleep patterns were restored to normal within a week. However levels of nerve cell production (neurogenesis) were not restored for two weeks, and the brain appears to boost its efforts in order to counteract the shortage.

Light to Matter to Light

Light and Matter United (includes videos) by William J. Cromie:

Lene Hau has already shaken scientists’ beliefs about the nature of things. Albert Einstein and just about every other physicist insisted that light travels 186,000 miles a second in free space, and that it can’t be speeded-up or slowed down. But in 1998, Hau, for the first time in history, slowed light to 38 miles an hour, about the speed of rush-hour traffic.

Two years later, she brought light to a complete halt in a cloud of ultracold atoms. Next, she restarted the stalled light without changing any of its characteristics, and sent it on its way. These highly successful experiments brought her a tenured professorship at Harvard University and a $500,000 MacArthur Foundation award to spend as she pleased.
…
Now Mallinckrodt Professor of Physics and of Applied Physics, Hau has done it again. She and her team made a light pulse disappear from one cold cloud then retrieved it from another cloud nearby. In the process, light was converted into matter then back into light. For the first time in history, this gives science a way to control light with matter and vice versa.