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.

How to Stay Healthy: Avoiding the Flu

It is no secret that washing your hands is a great strategy to stay healthy. Still few people take care to wash their hands thoroughly frequently during each day. The H1N1 Flu is just the latest sickness that washing your hands protects you from.

The CDC recommends you take these everyday steps to protect your health to protect yourself from the flu:

Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are also effective. Though the scientific evidence is not as extensive as that on hand washing and alcohol-based sanitizers, other hand sanitizers that do not contain alcohol may be useful for killing flu germs on hands.
Avoid touching your eyes, nose or mouth. Germs spread this way.
Try to avoid close contact with sick people.

And to keep others healthy you should

Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it. [others also suggest coughing into you elbow instead of your hands, again to reduce the spread of germs.]
If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.) Keep away from others as much as possible to keep from making others sick.

The spread of this 2009 H1N1 flu is thought to be happening in the same way that seasonal flu spreads. Flu viruses are spread mainly from person to person through coughing or sneezing of people with influenza. Sometimes people may become infected by touching something with flu viruses on it and then touching their mouth or nose.

The incidence of H1N1flu is likely to be high this flu season based on results in the Southern Hemishpere. Symptoms are those of the flu: fever, cough, sore throat, runny or stuffy nose, body aches, headache, chills and fatigue; can include diarrhea and vomiting.

The CDC includes weekly flu statistics on their web site. Since mid-April to August 30, 2009, a total of 9,079 hospitalizations and 593 deaths associated with 2009 influenza A (H1N1) viruses have been reported to CDC an increase from 8,843 hospitalizations and 556 deaths from the prior week.

Engineer Tried to Save His Sister and Invented a Breakthrough Medical Device

Here is another remarkable example of the great benefit engineers provide society.

How a software engineer tried to save his sister and invented a breakthrough medical device

I wanted to help my sister as much as I could. I went to Medline, where there are hundreds of thousands of documents describing clinical studies, to see what I could find.

There are billions of dollars spent every year on clinical studies. I was surprised to discover that there were sometimes clinical studies of treatments for which there were no clinical applications. The trials would show successful results but no clinical applications.

I found a 1987 Italian funded set of clinical studies that showed successful treatment of tumors by the application of chemotherapy directly into the tumors. But I could find nothing since then.
…
It took us two years to do the engineering. And it has taken the FDA seven years and two months to approve the product for sale. We were able to shorten the FDA process a little by saying that it was similar to other devices that had already been approved.

Great stuff.

Scientific Illiteracy Leaves Many at Risk in Making Health Care Judgements

Scientific literacy is important for many reasons and that importance has increased greatly over the last century. Medical research is often difficult to interpret. Often various studies seem to contradict each other. Often the conclusions that are drawn are far too broad (especially as the research conclusions are passed on and people hear of them overly simplified ways).

Many health care options are not obviously all good, or all bad, but instead a mix of benefits and risks, both of which include interactions with the individuals makeup. So we often see contradictory (and seemingly contradictory) advice. Without a level of scientific literacy it is very difficult for people to know how to react to medical advice.

We have numerous posts on the scientific inquiry process showing that acquiring scientific knowledge is complex and can be quite confusing in many instances. While understanding things are often less clear cut than they are presented it is still true that most often strategies for healthy living have far better practices that will provide far better results than alternatives.

The scientific illiteracy that has some think because their are risks no matter what is done that means there is no evidence some alternatives are far superior is very dangerous. As you can see in action now with those that risk their and others lives and health by doing things like not vaccinating their children, or driving when drunk, or driving when talking on a cell phone.

Without a scientifically literate society even completely obvious measures like not using antibiotics on viral infections are ignored.

Researchers Work to Protect Bats Against Deadly Disease

Researchers work to protect Wisconsin bats against deadly disease

Redell, who studies bats for the Department of Natural Resources, lives every day now with the threat of a disease called white-nose syndrome hanging over his head. The disease, though not yet in Wisconsin, has killed more than 90 percent of the cave bats in Eastern states such as New York and Vermont. Experts predict it could make its way to Wisconsin, with its eight species and hundreds of thousands of bats, in as little as two years.
…
One female little brown bat – with a body less than the length of your thumb – can eat its body weight in insects in one evening, Redell said. Such is the insect-hunting prowess of the bats that they are thought to save farmers billions of dollars in crop losses, according to Sheryl L. Ducummon, with Bat Conservation International.

In a recent scientific article on the ecological and economic importance of bats, Ducummon reported that, in one summer, the 150 bats in an average colony of big brown bats can conservatively eat 38,000 cucumber beetles, which attack corn and other farm crops. Damage from the beetle and their larvae cost corn farmers as much as $1 billion a year.

The loss of such an insect-eating force could be devastating, Redell said. The approximate 1 million bats that have already died of white-nose syndrome in the last three years on the East Coast would have eaten 700,000 tons of insects were they still hunting the night skies, he said.

Bats perform other important tasks, too. Several Western species serve crucial roles as pollinators for desert plants such as agave and as seed dispersers for dozens of species of cacti.
…
“I mean, this is like a mouse that flies, but it has the predatory capabilities of a polar bear,” Blehert said. “They are physically adapted to command the night sky. You’re talking about a little thing with a body less than half the size of your thumb whose heartbeat can get up to 1,000 beats a minute when they are flying but that can slow when they are hibernating in the winter to 4 beats a minute. And they live 20 to 25 years!”

Bats really are amazing and very valuable animals.

Friday Fun: Bristol Zoo’s Human Exhibit

Photo of the Homo Sapiens zoo sign at the Bristol Zoo

A mysterious sign has appeared on the side of the Zoo’s popular Coral CafÃ©, designating the area as a place to spot one of the world’s most widespread species – Homo sapiens. The notice, which appeared without warning this week, shows humans ‘on display’ inside the cafÃ© and includes tongue-in-cheek description of the species and its characteristics.

Zoo staff were surprised and amused to discover the new fixture. Dr Jo Gipps, Director of Bristol Zoo Gardens, said: “This is definitely not one of the Zoo’s own signs, it is clearly a prank and a very good one too. It looks completely genuine. We think it’s great sign and we have absolutely no intention of removing it, however I think one of them is probably enough.”

From the sign:

After a gestation period of nine months, the you usually live in the parents’ next for around 16 years. While the parents are out foraging for food, juveniles are looked after in large groups by other adults.

In adolescence, the offspring adopt a more nocturnal lifestyle and engage in ritualized activities of drinking fermented liquids and dancing to rhythmical sounds, which scientists believe may help them to find a mate.
…
They are known to adopt other species as pets, particularly dogs (canis lupus familians) and cats (felis catus).

Continue reading →

The Value of Displaying Data Well

Anscombe’s quartet: all four sets are identical when examined statistically, but vary considerably when graphed. Image via Wikipedia.

___________________
Anscombe’s quartet comprises four datasets that have identical simple statistical properties, yet are revealed to be very different when inspected graphically. Each dataset consists of eleven (x,y) points. They were constructed in 1973 by the statistician F.J. Anscombe to demonstrate the importance of graphing data before analyzing it, and of the effect of outliers on the statistical properties of a dataset.

Of course we also have to be careful of drawing incorrect conclusions from visual displays.

For all four datasets:

Property	Value
Mean of each x variable	9.0
Variance of each x variable	10.0
Mean of each y variable	7.5
Variance of each y variable	3.75
Correlation between each x and y variable	0.816
Linear regression line	$y = 3 + 0.5 x$

Edward Tufte uses the quartet to emphasize the importance of looking at one’s data before analyzing it in the first page of the first chapter of his book, The Visual Display of Quantitative Information.

Here Comes Science by They Might Be Giants

They Might Be Giants creates great music and has moved into creating music aimed at kids, of any age, over the last few years. They are releasing a new Album and animated DVD Here Comes Science, is being released tomorrow. Their music is both enjoyable to listen to and educational, something that is often attempted but rarely done as successfully as they do.

The release include the following songs and videos:

1. Science Is Real
2. Meet the Elements
3. I Am a Paleontologist w/Danny Weinkauf
4. The Bloodmobile
5. Electric Car w/Robin Goldwasser
6. My Brother the Ape
7. What Is a Shooting Star?
8. How Many Planets?
9. Why Does the Sun Shine?
Continue reading →

Experimenting Social Network

Social media is definitely a fad filled with lots of ways to waste time. It also does have real value, ways to connect to things people care about and wish to focus on. Reddit is a good site for finding interesting resources online. Sub-reddits are topical areas within Reddit (I have set up management and investing sub-reddits). A new experiment subreddit looks very interesting:

Each experiment will go through a few threads. The first step will be a query for experimental methods. Someone will present a problem or piece of information they want to find out, and then others will suggest methods. Once this is agreed upon, it will be carried out, and a second thread will be posted detailing the method and providing a place to post results via the comments. Then, a third thread can be made to discuss the results. Having more than one thread for every experiment will make things more accessible and easier to sort.

Don’t research ways other people have experimentally determined these things. Submit original ideas to the experimental design thread. Try to come up with a novel way to discover things, but don’t be completely limited by this suggestion. This is chiefly about rediscovery, not repeating someone else’s experiment, but sometimes there’s fun and merit in that as well.

I have joined. You can go to Reddit and join this subreddit to see experiences with experimenting to learn about the world around us.

Atomic Force Microscopy Image of a Molecule

The delicate inner structure of a pentacene molecule imaged with an atomic force microscope. For the first time, scientists achieved a resolution that revealed the chemical structure of a molecule. The hexagonal shapes of the five carbon rings in the pentacene molecule are clearly resolved. Even the positions of the hydrogen atoms around the carbon rings can be deduced from the image. (Pixels correspond to actual data points). Image courtesy of IBM Research – Zurich

IBM scientists have been able to image the “anatomy” — or chemical structure — inside a molecule with unprecedented resolution. “Though not an exact comparison, if you think about how a doctor uses an x-ray to image bones and organs inside the human body, we are using the atomic force microscope to image the atomic structures that are the backbones of individual molecules,” said IBM Researcher Gerhard Meyer. “Scanning probe techniques offer amazing potential for prototyping complex functional structures and for tailoring and studying their electronic and chemical properties on the atomic scale.”

The AFM uses a sharp metal tip to measure the tiny forces between the tip and the sample, such as a molecule, to create an image. In the present experiments, the molecule investigated was pentacene. Pentacene is an oblong organic molecule consisting of 22 carbon atoms and 14 hydrogen atoms measuring 1.4 nanometers in length. The spacing between neighboring carbon atoms is only 0.14 nanometers—roughly 1 million times smaller then the diameter of a grain of sand. In the experimental image, the hexagonal shapes of the five carbon rings as well as the carbon atoms in the molecule are clearly resolved. Even the positions of the hydrogen atoms of the molecule can be deduced from the image.

Read full press release: IBM Scientists First to Image the “Anatomy” of a Molecule
Continue reading →

Lego Mindstorms Robots Solving: Sudoku and Rubik’s Cube

LEGO Mindstorms Rubik’s Cube Solver

Tilted Twister solves Rubik’s cube fully automatically.
Just place the scrambled cube on Tilted Twister’s turntable. An ultrasonic sensor detects its presence and starts to read the colors of the cube faces using a light sensor. The robot turns and tilts the cube in order to read all the faces. It then calculates a solution and executes the moves by turning, tilting and twisting the cube.
…
The challenge was to build the robot using only the Lego Mindstorms NXT Retail-kit. And to make it completely independent, without need of being connected to a PC.
The Lego Mindstorms NXT Retail-kit contains three servo motors and four sensors (touch, light, ultrasonic and sound). How should I build the robot using only these items?
After a lot of experimenting I came up with a solution – If I tilted the whole robot, it would be possible for it to tilt the cube using only one motor, leaving the other two motors for turning the cube and for positioning the light sensor. Thus Tilted Twister.
…
Scanning the cube: 1 minute
Calculating a solution: 20 – 40 seconds
Executing the moves: 1 – 5 minutes. Average 4.5 minutes (60 faceturns)
Average total time: 6 minutes

Very cool. Related book: Building Robots With Lego Mindstorms