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.

Backyard Wildlife: Great Spreadwing Damselfly

photo of Dragonfly

If you know the what type of dragonfly is in the photo, please add a comment (update: a comment indicates it is not a dragonfly but a Great Spreadwing Archilestes grandis damselfly – I really enjoy getting feedback like this. It appears the most common way to differentiate the two is how the wings are at rest but the Spreadwing is an exception). I had a small preying mantis drop on my head, and then the ground, a month ago in my backyard. But when I got my digital camera I couldn’t find it again. The variety of insects you can see can be amazing, especially if you don’t use poisons and chemicals in your yard.

Photo by John Hunter, creative commons attribution license.

Engineer Uses Gravity

Now Diving: Sir Isaac Newton

On TV, a diver walks out onto a platform. The camera fixes on him. He waits. He leaps. And then — somehow — the camera stays with him as he plunges. In the instant it takes him to break the water’s surface, the picture suddenly cuts to an underwater shot — and we watch in disbelief as the dive culminates in a burst of bubbles.

How do they do it?

Well, there’s a rope. There’s a pulley. And the rope and the pulley work a contraption made out of a pipe. The whole gizmo is based on the brilliant insight that objects fall at the same rate regardless of mass. A Tuscan by the name of Galileo came up with it about 400 years ago; if he were alive, he’d call it cutting edge. And there’s the beauty of it: It’s sophisticated, yes, but only because it’s simple.
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Garrett Brown revolutionized the movie business 38 years ago when he invented the Steadicam, a mechanical arm for cameramen that smooths away the jerkiness of hand-held shots. Much later, he came up with the Skycam, which rides a web of wires above the heads of football players. In between, Mr. Brown, 66 years old, got his one-line brief from NBC: “They wanted a camera,” he says, “that stayed with divers, including going underwater with them.”
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The falling camera rides a rail on the inside of the pipe. A glass strip runs along the pipe’s full length; the camera takes its picture through the glass. From the diving platform to the water line, the glass is smoky. Below the line, it’s clear, so the camera need not adjust its exposure as it streaks into underwater darkness.

The pipe is caulked. The camera drops through air. “It doesn’t splash into the water,” Mr. Brown said. “That would look horrible.”

The appropriate use of technology is great to see. Applying knowledge well is a key to good engineering.

Engineers Should Follow Their Hearts

Steve Wozniak, Apple co-founder is a great engineer and full of wonderful quotes for engineers to take to heart. The autobiography of the Woz is certainly a good read for any engineer. Woz urges engineers to follow their hearts

Wozniak talked about a life driven by his passion for the electronics and computing. And passion can be a more important incentive than money, he said.
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“Sometimes when you’re short of resources it forces you to do better work,” he said. To design the Apple’s logic circuitry, “I couldn’t afford an online timeshare computer system. I had to write down ones and zeros (and simulate the computer’s operations). It was all done by hand, never once on a computer.”
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He offered his computer designs to HP five times, but they never were interested. “I would not sell something for money without my employer getting a cut of it.”

Life in a bubble

Hundreds of insect species spend much of their time underwater, where food may be more plentiful. MIT mathematicians have now figured out exactly how those insects breathe underwater.

By virtue of their rough, water-repellent coat, when submerged these insects trap a thin layer of air on their bodies. These bubbles not only serve as a finite oxygen store, but also allow the insects to absorb oxygen from the surrounding water.

“Some insects have adapted to life underwater by using this bubble as an external lung,” said John Bush, associate professor of applied mathematics, a co-author of the recent study.

Thanks to those air bubbles, insects can stay below the surface indefinitely and dive as deep as about 30 meters, according to the study co-authored by Bush and Morris Flynn, former applied mathematics instructor. Some species, such as Neoplea striola, which are native to New England, hibernate underwater all winter long.

Autism and the MMR vaccine

Science Tuesday: Back into the hornets nest is a thoughtful follow-up post on the decision of a scientist to vaccinate his child.

Autism isn’t like tuberculosis, there’s not a bacteria that causes the disease. In fact,most researchers believe that “autism” is not a discrete disorder, rather “autism is a clinically defined pervasive developmental disorder with phenotypically diverse neuropsychiatric symptoms and characteristics. These manifest as a spectrum of social and communicative deficits, stereotypical patterns and disturbances of behaviour.”Â¹
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If a particular trait’s heritability is 100% then the trait is due entirely to genetic variation, if the heritability is 0% then the trait is due entirely to environmental variation. By some estimates, heritability of autism spectrum disorders exceeds 90%
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repeated studies have found that autism diagnoses continue to rise even after the removal of thimerosal from the vaccine.
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Finally, when thinking about the environmental influences on autism, it’s important to explore the role of the environment on genetics. Many of the types of genetic changes that have been identified as causative in autism are indicative of some sort of DNA damage – DNA damage that may result from exposure to an environmental toxin. Many scientists, and I count myself in their number, feel that the recent autism ‘epidemic’ is due primarily to improved screening and diagnosis. In other words, prior to the 1980’s, many people suffering from autism were diagnosed as “slow” or misdiagnosed with another type of mental retardation. Unfortunately, there is no way to quantify this hypothesis.

This is one of the examples of what is so good about blogs. Great content that probably would not be available but through a blog.

Google.org Invests $10 million in Geothermal Energy

Google is investing huge sums in renewable energy with the aim of cheaper than coal renewable energy. Google.org (the philanthropic arm of Google) announced $10.25 million in investments in a breakthrough energy technology called Enhanced Geothermal Systems (EGS).

EGS expands the potential of geothermal energy by orders of magnitude. The traditional geothermal approach relies on finding naturally occurring pockets of steam and hot water. The EGS process, by comparison, replicates these conditions by fracturing hot rock, circulating water through the system, and using the resulting steam to produce electricity in a conventional turbine.

A recent MIT report on EGS estimates that just 2% of the heat below the continental United States between 3 and 10 kilometers, depths within the range of current drilling technology, is more than 2,500 times the country’s total annual energy use.

“EGS could be the ‘killer app’ of the energy world. It has the potential to deliver vast quantities of power 24/7 and be captured nearly anywhere on the planet. And it would be a perfect complement to intermittent sources like solar and wind,” said Dan Reicher, Director of Climate and Energy Initiatives for Google.org.

Google’s Renewable Energy Cheaper than Coal initiative focuses on solar thermal power, advanced wind, EGS and other potential breakthrough technologies. Google has set a goal to produce one gigawatt of renewable energy capacity, enough to power a city the size of San Francisco, in years, not decades.
Continue reading →

Huge Ant Nest

[Google broke the original link when they trashed Google Video in poor way, which has become their habit. There history now shows they create very unreliable web services that are an embarrassment to any engineer. Still YouTube is difficult to avoid, Vimeo while not suffering from being a Google product and therefore unreliable based on Google’s history, Vimeo offers only a small fraction of the content found on YouTube.]

Very cool webcast. The ant nest goes 8 meters into the earth. The nest is engineered with vents to promote the flow of air, bringing in fresh air and expelling carbon dioxide created by the large fungus gardens. The scientists filled the ant next with concrete to excavate it: 10 tons of concrete were needed.

Using Spice-based Compound To Kill Cancer Cells

Synthetic molecules, derived from curcumin, a naturally occurring compound found in the spice turmeric have been killed cancer cells, in lab settings. Centuries of anecdotal evidence and recent scientific research suggest curcumin has multiple disease-fighting features, including anti-tumor properties. However, when eaten, curcumin is not absorbed well by the body. Instead, most ingested curcumin in food or supplement form remains in the gastrointestinal system and is eliminated before it is able to enter the bloodstream or tissues.

James Fuchs, assistant professor of medicinal chemistry and pharmacognosy at Ohio State University and principal investigator on the project, and colleagues are continuing to refine compounds that are best structured to interact with a few overactive proteins that are associated with cell activity in breast and prostate cancers. Blocking these molecular targets can initiate cell death or stop cell migration in the cancers.

A major component of their strategy is called structure-based, computer-aided design, a relatively new technology in the drug discovery field. Before ever working with an actual compound, the scientists can make manipulations to computer-designed molecules and observe simulated interactions between molecules and proteins to predict which structural changes will make the most sense to pursue.

“Most of the interaction between our compound and the overactive protein comes from what are called hot spots on the protein’s surface,” said Chenglong Li, assistant professor of medicinal chemistry and pharmacognosy at Ohio State and an expert in computational chemistry. “For each spot, we can design small chemical fragments and link them together to make a molecule. This is what computer-aided design and modeling can do.”

Some of the most effective compounds have been tested for their effectiveness against human cancer cell lines – as well as whether they might be toxic to healthy cells. So far, the molecule favored by the researchers has a nearly 100-fold difference in toxicity to cancer cells vs. healthy cells, meaning it takes 100 times more of the compound to kill a healthy cell than it does to kill a cancer cell.

Lake Superior vs. Silicon Valley Hot Spots

Nice post from Rich Hoeg – Lake Superior vs. Silicon Valley Hot Spots:

Recently I had the opportunity to visit friends in Silicon Valley. While riding the light rail in Mountain View, I experienced a moment of revelation of how life differs between the shores of Lake Superior and Silicon Valley. Six young men boarded the train … all obviously geeks in their young 30’s … their laptops (all Apples) were already fired up and ready. They proceeded to have a LAN party while riding the light rail on the way to work. Why was this possible?? You need to understand that Google provides free wireless to the entire town on Mountain View. The world is connected … and interacts in different ways … at least in Silicon Valley.
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Thus, life is different on the shores of Lake Superior. I am a lone software nerd looking for a wireless hotspot … not a light rail rider with free unlimited access anywhere in my community. Out in Silicon Valley I tried Google’s connection; it worked fine and did not ask for anything beyond my normal Google account.

This is one small example of why Silicon Valley is so successful. To be economically successful, countries need to focus on big things (investing in infrastructure, sensible laws relating to innovation, creating and maintaining good capital markets, investing in science and engineering education, encouraging entrepreneurs, transportation systems…) and the small stuff like this. Silicon Valley continue to be a bright light (as do other places, like Boston) but overall the USA seems to be trailing, not leading, far too often lately.

Science Sortof Explains: Hiccups

photo of Red Hot Pepper by John Hunter

I love spicy food (Indian food is my favorite food). In my garden, this year, I am growing some spicy peppers (which honestly I don’t really like on their own – I have discovered). Still I eat them some and I get the hiccups almost every time. So I finally used Google to find out why. That lead to – MayoClinic on Hiccups:

A hiccup is an unintentional contraction of your diaphragm – the muscle that separates your chest from your abdomen and plays an important role in breathing. This contraction makes your vocal cords close very briefly, which produces the sound of a hiccup.

Although there’s often no clear cause for a bout of hiccups, some factors that can trigger acute or transient hiccups include: Eating spicy food. Spicy food may cause irritation to the nerves that control normal contractions of your diaphragm.

I must say the internet is great. Still that is hardly a great explanation for me. I almost never get the hickups eating spicy meals but every time I eat a hot pepper on its own I seem to (which happens very quickly and then ends pretty quickly – under 5 seconds). I guess somehow the other food in my mouth disrupts the potential nerve irritation so that it doesn’t cause a hiccup? It doesn’t seem like the raw pepper is hotter (higher Scoville Heat Unit) than the food, so I don’t think it is just a matter of more “heat” causing the hiccups.

Photo by John Hunter, Creative Commons Attribution-Share Alike (see requirements for use).