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.

2 Mysterious Species in the UK

Plane Bug - UK

Mystery insect found in Museum garden

This mystery bug has not been seen in the UK before and has made the Natural History Museum’s Wildlife Garden its home. The tiny bug is baffling insect experts at the Museum who are still trying to identify the mystery newcomer. The almond-shaped bug is red and black and about the size of a grain of rice
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Experts checked the new bug with those in the Museum’s national insect collection of more than 28 million specimens. Amazingly, there is no exact match.
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The bug closely resembles the fairly rare species Arocatus roeselii, which is usually found in central Europe. However, the roeselii bugs are brighter red than this new bug and they are usually associated with alder trees rather than plane trees.

However, the National Museum in Prague discovered an exact match to the mystery bug in their collections – an insect that was found in Nice and is classified as Arocatus roeselii. ‘There are two possible explanations,’ explains Barclay. ‘That the bug is roeselii and by switching to feed on the plane trees it could suddenly become more abundant, successful and invasive. The other possibility is that the insect in our grounds may not be roeselii at all.’

The Museum is working with international colleagues to analyse the bug’s body shape, form and DNA to see whether it is a newly discovered species or if it is in fact Arocatus roeselii.

Here is a green bug from my trip to Clifton Gorge Nature Preserve that is probably easier to identify. Or how about this insect from the Forest Glen Preserve, Illinois. Or how about this one at Our Lady of Gethsemani Abbey, in Kentucky.

Help us find out more about the mysterious alien “Ghost Slug”
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Speciation of Dendroica Warblers

Speciation for Dendroica Warblers

They developed a mathematical model that attributed patterns of speciation to the way that closely related species divide up their environment. According to this model, when there are few relatives around to compete for resources, such as when an environment is first colonized, species differentiate rapidly.
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This model is robust: even when the authors assumed that their phylogenetic tree contains only 25 percent of all Dendroica species, they found that their Î³ test was still valid, indicating that this genus experienced an explosive bout of adaptive radiation before settling down to a “more normal” rate of speciation.

This mathematical model provides an incisive tool to gain a clearer understanding of the pattern and rate of speciation for groups of closely related species, even in the absence of a fossil record, simply by analyzing their DNA.

A Whale of a Turbine

A whale of a turbine

a flipperlike prototype is generating energy on Canada’s Prince Edward Island, with twin, bumpy-edged blades knifing through the air. And this summer, an industrial fan company plans to roll out its own whale-inspired model – moving the same amount of air with half the usual number of blades and thus a smaller, energy-saving motor.

Some scientists were sceptical at first, but the concept now has gotten support from independent researchers, most recently some Harvard engineers who wrote up their findings in the respected journal Physical Review Letters.
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when models of the bumpy flippers were tested in a wind tunnel, Fish and his colleagues found something interesting. The flippers could be tilted at a higher angle before stall occurred.

The scientific literature had scant reference to the flipper bumps, called tubercles. Fish reasoned that because the whale’s flippers remained effective at a high angle, the mammal was therefore able to manoeuvre in tight circles. In fact, this is how it traps its prey, surrounding smaller fish in a “net” of bubbles that they are unwilling to cross.

In 2004, along with engineers from the US Naval Academy and Duke University, Fish published hard data: Whereas a smooth-edged flipper stalled at less than 12 degrees, the bumpy, “scalloped” version did not stall until it was tilted more than 16 degrees – an increase of nearly 40 percent.

Fish then partnered with Canadian entrepreneur Stephen Dewar to start WhalePower, a Toronto-based company that licenses the technology to manufacturers.
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It has all been a bit of a culture shock for Fish, who is more at home in the open world of academia than the more secretive realm of inventions and patents. Two decades ago, his only motivation was to figure out what the bumps were for.

“I sort of found something that’s in plain sight,” he says. “You can look at something again and again, and then you’re seeing it differently.”

500 Year Floods

Why you can get ‘500 year floods’ two years in a row by Anne Jefferson:

Flood probabilities are based on historical records of stream discharge. Let’s use the Iowa River at Marengo, Iowa as an example. It reached a record discharge of 46,600 cubic feet per second* (1320 m3/s) on 12 June. That flow was estimated to have a 500 year recurrence interval, based on 51 years of peak flow records
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When you are extrapolating beyond your data by an order of magnitude, the highest points in the dataset start to have a lot of leverage. Let’s imagine that there’s another big flood on the Iowa River next year and we do the same analysis. Now our dataset has 52 points, with the highest being the flood of 2008. When that point is included in the analysis, a discharge of 46,600 cubic feet per second* (1320 m3/s) has a recurrence interval of <150 years (>0.6%). It’s still a darn big flow, but it doesn’t sound quite so biblical anymore.
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Urbanization and the adding of impervious surface is one cause of increasing flood peaks, but in Iowa, a more likely culprit is agricultural.

This post is a good explanation that the 500 year flood idea is just way of saying .2% probability (that some people confuse as meaning it can only happen every 500 years). But I actually am more interested in the other factor which is how much estimation is in “500 year prediction.” We don’t have 500 years of data. And the conditions today (I believe) are much more likely to create extreme conditions. So taking comfort in 500 year (.2%), or even 100 year (1% probability) flood “predictions” is dangerous.

It would seem to me, in fact, actually having a 500 year flood actually increases the odds for it happening again (because the data now includes that case which had not been included before). It doesn’t actually increase the likelihood of it happening but the predictions we make are based on the data we have (so given that it happens our previous 500 year prediction is questionable). With a coin toss we know the odds are 50%, getting 3 heads in a row doesn’t convince us that our prediction was bad. And therefore the previous record of heads or tails in the coin toss have no predictive value.

I can’t see why we would think that for floods. With the new data showing a flood, (it seems to me) most any model is likely to show an increased risk (and pretty substantial I would think) of it happening again in the next 100 years (especially in any area with substantial human construction – where conditions could well be very different than it was for our data that is 20, 40… years old). And if we are entering a period of more extreme weather then that will likely be a factor too…

The comments on the original blog post make some interesting points too – don’t miss those.

The Brain Hides Information From Us To Prevent Mistakes

“The main finding of the study is that it has enabled us to confirm that tactile sensations are initially located unconsciously in anatomical coordinates, but they reach our awareness only when the brain has formed an image of their origin in the spatial coordinates, external to the body,” explained Salvador Soto-Faraco. The coexistence of different spatial reference frames in the brain has been known for some time. So has the fact that confusions between them may result in some cases, such as when we invert the usual anatomical position of some body parts (e.g. when crossing our arms over the body midline). “The brain sorts out problems of this kind rapidly, in a matter of tenths of a second. To do so, however, it has to integrate information arriving in formats that are quite disparate”, Sotoa-Faraco added. “Our research has helped us understand how this process works and how the brain manages spatial realignment when faced with conflict”, he concluded.

Interesting. I think my brain might be hiding more from me lately (like right now where the key to my shed is) 🙂

Too Toxic for Microorganisms – Not

The Pit of Life and Death by Richard Solensky:

The water became as acidic as lemon juice, creating a toxic brew of heavy metal poisons including arsenic, lead, and zinc. No fish live there, and no plants line the shores. There aren’t even any insects buzzing about. The Berkeley Pit had become one of the deadliest places on earth, too toxic even for microorganisms. Or so it was thought.
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the researchers identified it as Euglena mutabilis, a protozoan which has the remarkable ability of being able to survive in the toxic waters of the Berkeley Pit by altering its local environment to something more hospitable. Through photosynthesis, it increases the oxygen level in the water, which causes dissolved metals to oxidize and precipitate out. In addition, it pulls iron out of the water and sequesters it inside of itself. This makes it a classic example of an extremophile.

Magnetic Movie

Magnetic Movie from Semiconductor on Vimeo

Magnetic Movie was shot in NASA’s Space Sciences Laboratories at UC Berkeley for Chanel 4 in association with the Arts Council of England.

In Magnetic Movie, Semiconductor have taken the magnificent scientific visualisations of the sun and solar winds conducted at the Space Sciences Laboratory and Semiconducted them. Ruth Jarman and Joe Gerhardt of Semiconductor were artists-in-residence at SSL. Combining their in-house lab culture experience with formidable artistic instincts in sound, animation and programming, they have created a magnetic magnum opus in nuce, a tour de force of a massive invisible force brought down to human scale, and a “very most beautiful thing.”

Magnetic Movie is the aquavit, something not precisely scientific but grants us an uncanny experience of geophysical and cosmological forces.

Cool video: I must admit I am confused at how extensive the artistic license taken with the animation is.

Ninja Professors

From the excellent Piled Higher and Deeper comic strip by Jorge Cham, www.phdcomics.com. Like many of the best comics (Dilbert, xkcd) 🙂 PhD is authored by an engineer: Jorge Cham got his PhD in Mechanical Engineering at Stanford University, and was a full-time Instructor and researcher at the California Institute of Technology.

US Navy Sponsored Technology Summer Camp

US Navy plants a new seed of future engineers

When 14-year-old Dayne Savory first heard about a summer camp on technology in suburban Maryland, he had no idea that he would become so interested in science and engineering.

“Even though engineering was not one of my first options, now I will consider it. After attending this program I realized that I was able to do this,” Long Island resident Savory said.

Worried about the steep decline in U.S. science and engineering graduates, U.S. institutions such as the Navy and the NAVSEA — the command in charge of building, buying and maintaining the Navy’s ships- are promoting technology camps and competitions around the country. They’re doing it through partnerships with a growing number of associations such as the nonprofit Seat Pleasant, Md.-based Patriots Technology Training Center.
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The students built underwater robots and held a competition on July 3 at Prince George’s Sports and Learning Complex.

Thurman Jones, president of the Patriots Technology Training Center, said that the number of participants grows every year. To support this summer’s edition -as well as other programs organized by the Patriots Center — the U.S. Navy and the NAVSEA provided more than $100,000 worth of in cash, technical equipment and volunteers, according to Jones.

How Prozac Sent Science Inquiry Off Track

I post often on examples of scientific inquiry in action. I think it is an important way to see how science works while searching for answers. The process is not a simple one, but after a solution is found it can often be presented as obvious. But while trying to find answers it is quite difficult.

How Prozac sent the science of depression in the wrong direction

But the success of Prozac hasn’t simply transformed the treatment of depression: it has also transformed the science of depression. For decades, researchers struggled to identify the underlying cause of depression, and patients were forced to endure a series of ineffective treatments. But then came Prozac. Like many other antidepressants, Prozac increases the brain’s supply of serotonin, a neurotransmitter. The drug’s effectiveness inspired an elegant theory, known as the chemical hypothesis: Sadness is simply a lack of chemical happiness. The little blue pills cheer us up because they give the brain what it has been missing.

There’s only one problem with this theory of depression: it’s almost certainly wrong, or at the very least woefully incomplete. Experiments have since shown that lowering people’s serotonin levels does not make them depressed, nor does it does not make them depressed, nor does it worsen their symptoms if they are already depressed.
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In this sense, Prozac is simply a bottled version of other activities that have a similar effect, such as physical exercise.
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It is jarring to think of depression in terms of atrophied brain cells, rather than an altered emotional state. It is called “depression,” after all. Yet these scientists argue that the name conceals the fundamental nature of the illness, in which the building blocks of the brain – neurons – start to crumble. This leads, over time, to the shrinking of certain brain structures, like the hippocampus, which the brain needs to function normally.