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.

Computer Science Unplugged

Computer Science Unplugged offers a free, interesting collection of activities designed to teach the fundamentals of computer science without requiring a computer. Because they’re independent of any particular hardware or software, Unplugged activities can be used anywhere, and the ideas they contain will never go out of date. Unplugged activities have been trialled and refined over 15 years in classrooms and out-of-school programs around the world maintained by the University of Canterbury in Christchurch New Zealand.

Topics include: Binary Numbers, Text Compression, Error Detection, Searching Algorithms, Sorting Algorithms, Steiner Trees and Public Key Encryption.

Clay Versus MRSA Superbug

“Healing clays” hold promise in fight against MRSA superbug infections and disease

Scientists from Arizona State University report that minerals from clay promise could provide inexpensive, highly-effective antimicrobials to fight methicillin-resistant Staphylococcus aureus (MRSA) infections that are moving out of health care settings and into the community.
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Unlike conventional antibiotics routinely administered by injection or pills, the so-called “healing clays” could be applied as rub-on creams or ointments to keep MRSA infections from spreading
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In their latest study, funded by the National Institutes of Health, Williams, Haydel and their colleagues collected more than 20 different clay samples from around the world to investigate their antibacterial activities… The researchers identified at least two clays from the United States that kill or significantly reduce the growth of these bacteria

Also listen to a podcast with the researchers, Lynda Williams and Shelly Haydel, that provides much more detail. The Science Studio podcasts from Arizona State University provides great science podcasts.

First Lungless Frog Found

The first recorded species of frog that breathes without lungs has been found in a clear, cold-water stream on the island of Borneo in Indonesia. The frog, named Barbourula kalimantanensis, gets all its oxygen through its skin.
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Previously the only four-limbed creatures known to lack lungs were salamanders. A species of earthwormlike, limbless amphibian called a caecilian is also lungless. Tetrapods, or four-limbed creatures, that develop without lungs are rare evolutionary events, Bickford and colleagues write.

The trait in amphibians is likely an adaptation to life between water and land and their ability to respire through the skin. The researchers suggest lunglessness in B. kalimantanensis may be an adaptation to the higher oxygen content in fast-flowing, cold water.
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Wake added that for most amphibians, the majority of gas exchange happens through the skin. A low but significant amount of respiration occurs via simple, sac-like lungs. Most species, he noted, have mating calls that require lungs. So biologists are unsure why a few species have entirely gotten rid of the organs, Wake said.

Engineers Without Borders

Engineering as diplomacy

You cannot look into the eyes of a child who is dying from a disease caused by drinking dirty water — something that rarely, if ever, happens in the United States — and not feel changed. You cannot stand before her parents without thinking, “I’m an engineer. There must be something I can do.”
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A year later, I returned with 10 engineering students from the University of Colorado. We devised a rudimentary pumping system, bringing water to the people of San Pablo. Today, the village’s young girls go to school and are healthier.

That trip was a transforming experience, not just for the villagers, but also for me. Intuitively, we engineers like things big — expansive bridges, colossal dams, massive tunnels. My experience taught me that small-scale engineering can have the most impact on people’s lives.

When I returned to Boulder, I began building something else: Engineers Without Borders — USA. The organization was formed out of the conviction that engineers have a leadership role to play in addressing some of the world’s most serious problems: contaminated water, poor sanitation systems, expensive or harmful energy sources.

In a world focused on bigger and newer, there is growing recognition that small-scale engineering can play a major role in helping end the cycle of poverty that persists among almost half the world’s population. Studies by the World Bank and United Nations suggest the most basic technology is critical to bringing more than 3 billion people out of poverty.

Today EWB-USA counts more than 11,000 student and professional engineers as members and works in 43 countries on 300 projects involving water, sanitation, energy and shelter. Whether it’s combining sustainable technologies with advanced construction techniques to bring affordable housing to pockets of the world, drilling drinking water wells in Kenya, constructing fog collectors in the Himalayas to harvest fresh water or installing solar panels to provide energy for a remote hospital in Rwanda, we are healing communities throughout the globe, giving people dignity and hope for better lives.

Engineers without Borders is another vivid example of the benefits engineering brings to society.

Matter-Antimatter Split Hints at Physics Breakdown

Nature may have handed scientists a new clue in a longstanding mystery: how matter beat out antimatter for dominance of the universe. Early data from twin experiments at the Tevatron, the world’s reigning particle accelerator at Fermi National Accelerator Laboratory (Fermilab) in Batavia, Ill., suggest an unexpected chink in the hugely successful standard model of particle physics.

The twist comes from odd behavior in a particle called the BS (pronounced “B-sub-S”), which flips back and forth between its matter and antimatter forms three trillions times per second. Researchers believe that such a breakdown, known as CP violation, is required to explain why matter is so abundant.

Researchers say the finding is well worth following up to make sure it is not a random clump in the data, as frequently happens in particle physics experiments.
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Neither result on its own was very convincing, so a team of European researchers combined the data, similar to the way medical researchers cull information from independent clinical trials, to look for rare side effects. Together, the data make it 99.7 percent likely that the discrepancy is real, not due to chance, says physicist Luca Silvestrini… Such analyses require making judgment calls, but Silvestrini says he is confident in the finding.

We posted on this study last month in: Explaining the Missing Antimatter

Coopers Rock State Forest, West Virginia

photo of Coopers Rock State Forest in West Virginia

See more photos of my visit last year to Coopers Rock State Forest in West Virginia. The day before I visited Rocky Gap State Park in Maryland. Photos by John Hunter.

False Teeth For Cats

False Teeth For Cats! What Next?

A team of eight British college students, calling themselves Fangs A Lot, have created the first false tooth for a cat and set up a business, Animal Solutions, to market false teeth for cats, dogs, and other animals. The group and its prototype false cat tooth have made it to the finals of the Ideas Igloo Roadshow, an invention contest for college students sponsored by Britain’s Make Your Mark Campaign and Microsoft, UK.

False teeth for cats may sound ridiculous, but they could be a solution to a serious problem for cats. Cats have notoriously bad dental problems. Cat owners seldom brush their cats’ teeth or scrape the surfaces of the teeth to remove plaque. By the time a cat is 3 or 4 years old, she may already have periodontal disease that can lead to tooth loss. Tooth loss may also come about as a result of tooth breakage, particularly in the canine teeth.

Link provided via our post suggestion page.

Scientists Witness the Birth of a Brain Cell

The Birth of a Brain Cell: Scientists Witness Neurogenesis

For the first time, researchers have developed a way to view stem cells in the brains of living animals, including humans—a finding that allows scientists to follow the process neurogenesis (the birth of neurons). The discovery comes just months after scientists confirmed that such cells are generated in adult as well as developing brains.
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The key ingredient in this process is a substance unique to immature cells that is neither found in mature neurons nor in glia, the brain’s nonneuronal support cells. Maletic-Savatic and her colleagues collected samples of each of the three cell types from rat brains (stem cells from embryonic animals, the others from adults) and cultured the varieties separately in the lab. They were able to determine the chemical makeup of each variety – and isolate the compound unique to stem cells – with nuclear magnetic resonance (NMR) spectroscopy. (NMR helps to determine a molecule’s structure by measuring the magnetic properties of its subatomic particles.) Although the NMR could identify the biomarker, but not its makeup, Maletic-Savatic speculates it is a blend of fatty acids in a lipid (fat) or lipid protein.

Aztec Math

Aztec Math Decoded, Reveals Woes of Ancient Tax Time

By reading Aztec records from the city-state of Tepetlaoztoc, a pair of scientists recently figured out the complicated equations and fractions that officials once used to determine the size of land on which tributes were paid. Two ancient codices, written from A.D. 1540 to 1544, survive from Tepetlaoztoc. They record each household and its number of members, the amount of land owned, and soil types such as stony, sandy, or “yellow earth.”

“The ancient texts were extremely detailed and well organized, because landowners often had to pay tribute according to the value of their holdings,” said co-author Maria del Carmen Jorge y Jorge at the National Autonomous University in Mexico City, Mexico. The Aztecs recorded only the total area of each parcel and the length of the four sides of its perimeter, Jorge y Jorge explained. Officials calculated the size of each parcel using a series of five algorithms—including one also employed by the ancient Sumerians—she added.

Aztec math finally adds up

That meant that some of the unknown symbols had to represent fractions of a rod, she said. By trial and error, she decoded the system. A hand equaled 3/5 of a rod, an arrow was 1/2 , a heart was 2/5 , an arm was 1/3 , and a bone was 1/5 .

A set of at least five formulas emerged showing how the Aztec surveyors determined the areas of irregular shapes. In some cases, the Aztecs averaged opposite sides and then multiplied. In others, they bisected the fields into triangles.

Bacteria Survive On All Antibiotic Diet

Bacteria Survive on All-Antibiotic Diet

The scientists wanted to make sure they had a good control—a group of bacteria that didn’t grow at all—so they bathed some of the bacteria in antibiotics. But there was a problem: The bacteria didn’t just survive in the antibiotics, they consumed them. The researchers then gathered soil from 11 sites with varying degrees of exposure to human-made antibiotics (from manure-filled cornfields to an immaculate forest) and found that every site contained bacteria, including relatives of Shigella and the notorious E. coli that could survive solely on antibiotics. And these weren’t just piddling doses—the bacteria could tolerate levels of antibiotics that were up to 100 times higher than would be given to a patient, and 50 times higher than what would qualify a bacterium as resistant.