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.

Big Big Lions

Lions Hunting in the Water

Relentless Enemies program to air on National Geographic in January.

The superlions marooned on an island by Zoe Brennan discusses the program:

“We discovered this tiny sandy island in the Okavango,” says Dereck. “It is extraordinary because it became totally isolated from the mainland 15 years ago when the course of the river changed, and a huge herd of buffalo and lions were trapped on a piece of land measuring 200 square kilometres.”

Through this twist of geographical fate, these two ancient species are now engaged in a desperate battle of survival — watched by six bemused refugee wildebeest and a handful of similarly outnumbered warthogs.

Thus, the island has become a unique, ecological experiment. In order to exist without the customary spectrum of weaker African prey like zebra, giraffe and impala, the Duba lions have had to develop distinct strategies in order to trap the single available food source.

Scientists Building a Safer Mosquito

Scientists building a better mosquito by Catherine Clabby:

Eliminating the pests appears impossible. But scientists are attempting to re-engineer them so they cannot carry disease. If they manage that, they must create enough mutants to mate with wild insects and one day to outnumber them.

Researchers chasing this dream, including an N.C. State University entomologist, know they may court controversy. Genetically modified crop plants such as soybeans, corn and cotton have become common in the United States, but an altered organism on wings would be a first.
…
Gould is working on the project with scientists on four continents. They landed $19.7 million under a Grand Challenges in Global Health grant offered by the Gates philanthropy and a National Institutes of Health foundation. The funders selected researchers ready to collaborate rather than compete on risky research aimed at solving massive health threats in poor places.

The genetic tinkering is focused at first on dengue, a tropical virus re-emerging in Asia, Latin America and Africa. While dengue claims a fraction of the million or more victims that malaria kills annually, it strikes 50 to 100 million people each year with severe flu symptoms. Outbreaks disrupt families and communities and overburden health systems.

Ageless Turtles

All but Ageless, Turtles Face Their Biggest Threat: Humans by Natalie Angier:

Dr. Christopher J. Raxworthy, the associate curator of herpetology at the American Museum of Natural History, says the liver, lungs and kidneys of a centenarian turtle are virtually indistinguishable from those of its teenage counterpart, a Ponce de Leonic quality that has inspired investigators to begin examining the turtle genome for novel longevity genes.

“Turtles don’t really die of old age,” Dr. Raxworthy said. In fact, if turtles didn’t get eaten, crushed by an automobile or fall prey to a disease, he said, they might just live indefinitely.

Turtles have the power to almost stop the ticking of their personal clock. “Their heart isn’t necessarily stimulated by nerves, and it doesn’t need to beat constantly,” said Dr. George Zug, curator of herpetology at the Smithsonian Institution. “They can turn it on and off essentially at will.”

Micro-robots to ‘swim’ Through Veins

image of Escherichia coli bacterium with flagella

Micro-robots take off
Photo: Transmission Electron Microscopy photograph of an Escherichia coli bacterium with flagella. The micro-robots are being developed to mimic the swimming behaviour of E.coli.

Micro-robots that can ‘swim’ through the vascular and digestive systems of the human body to perform medical tasks via remote control and, in many cases, avoid invasive major surgery, are being developed at Monash University following today’s announcement that the project has been funded through the Australian Research Council’s Discovery Projects scheme.

Physics Concepts in 60 Seconds

Physics Concepts in 60 Seconds from Symmetry Magazine (from Fermilab and the Stanford Linear Accelerator Center). The magazine is open access journal funded by the US Department of Energy. The complete antimatter in 60 seconds by Michael Doser, CERN:

Antimatter is made up of particles with equal but opposite characteristics of everyday particles of matter. Consider this analogy: dig a hole, and make a hill with the earth you’ve excavated. Hole and hill have equal but opposite characteristics— the volume of the earth in the hill, and that of the hole where the earth was removed. For particles, properties like electrical charge are opposite to their antiparticles—one positive, one negative. Also, antimatter will annihilate its matter counterpart in a burst of energy, just like the hill will fill the hole, leaving neither.

The universe seems to contain no significant amounts of antimatter, despite expectations that both should have been created equally during the big bang. So where did all the antimatter go? One possible explanation could be a subtle and unexpected difference in the properties of matter and antimatter, leading to a slight excess of matter which survived the initial cataclysm of matter-antimatter annihilation.

Experimenters at CERN, Fermilab, SLAC and KEK are producing antimatter in particle accelerators to search for and study this difference. Antimatter also has real-life medical applications, such as positron emission tomography—PET scans. But because producing antimatter even in minuscule quantities is very difficult, it will unfortunately never power any future Starship Enterprise.

Diving Mandarin Ducklings

Bummer BBC refused to let us watch this on You Tube and their videos rarely work and are hard to find so I just removed the link. You can try them Via: Inky Circus

The video was very cute.

How Does the Immune System Remember

Scientists find key to immune system’s ability to remember

The protein, which scientists call Lck, is essential for immune system T cells – white blood cells that attack virus-infected cells, foreign cells and cancer cells… Lck is important in helping “naive” T cells – those cells that have never been exposed to a particular pathogen – capture the receptor template of the invading agent and store it for future reference… Following infection or vaccination, Lck initiates a biochemical chain of events that vastly increases the number of T cells that march off to combat the invader.

After the infection subsides, the number of T cells marshaled to fight that agent decreases dramatically. But a smaller subset, known as “memory” cells, retains the imprint of its previous encounter should the pathogen make a return appearance. According to the study, while Lck primes naive cells to fight a pathogen, it is not required by memory cells, which initiate the fast and furious response when that same pathogen comes calling again years later. Unlike naive T cells, which are confined to the lymphatic system, memory T cells are found everywhere in the body, enabling them to sense and react more quickly when an infectious agent is reencountered.

Fun Fungi

Impudence, Thy Name is Mushroom

Fungi, on the other hand, are fundamentally alien.
…
Some lurk in the Earth, spreading out over hundreds of acres. Others live inside insects, forcing them to climb to the tip of a blade of grass, so that they can shower their spores down on new victims. Instead of ingesting their food, fungi dump their digestive enzymes into their surroundings and suck up the ensuing goo. Their reproductive cycles are like labyrinths. And of the estimated 1.5 million species of fungi on Earth, scientists have identified only five percent.

Flushed Drugs Pollute Water

Flushed drugs pollute water by Ron Seely (site broke the link so I removed it):

An extensive nationwide study by the U.S. Geologic Survey has found evidence of pharmaceuticals including antibiotics and hormonal drugs, such as birth control pills, in surface waters throughout the nation.
…
Whether the presence of drugs in water translates into human health impacts is still being studied. But research has shown that drugs containing hormones such as estrogen are causing changes and deformities in fish and other aquatic creatures.

The World Health Organization indicates that human risk assessments have shown low concentrations of pharmaceuticals in drinking water have a negligible health risk. But WHO points out that long-term exposures have not been evaluated, especially in populations with other illnesses or with compromised immune systems. Also, according to the WHO, antibiotics in water supplies are a potential concern because the most frequently used antibiotics are becoming less effective as the infections they are designed to combat become resistant.

Ocean Warming’s Effect on Phytoplankton

Ocean warming’s effect on phytoplankton:

When the climate warms, there is a drop in the abundance of the ocean’s phytoplankton, the tiny plants that feed krill, fish and whales, according to scientists who say new research offers the first clues to the future of marine life under global warming.

Ocean temperatures have generally risen over the last 50 years as the atmosphere warms. And now nine years of NASA satellite data published today in the journal Nature show that the growth rate and abundance of phytoplankton around the world decreases in warm ocean years and increases in cooler ocean years.