Science News

Headlines

. Follow the poop ! On the bird flu trail
. Cockroaches welcome: tell us how you eat
. Such a soft dinosaur
. Erupting volcanoes -- on Mars !
. Where is all the oil ? -- Oil spill update

Follow the poop !
We all know what a scare bird flu caused among us a few years ago. The menace continues to haunt us, we keep hearing of deaths from bird flu. How do scientists track and study how bird flu spreads ?
Don't get disgusted, one of the best ways is to "follow the poop". To be more specific, duck droppings can give important clues about the spread of bird flu.
Bird flu, which is also called avian influenza, is caused by viruses carried around by birds. These viruses are contagious, which means bird flu can spread from wild birds to birds kept by people, such as chickens and some ducks. One of the ways disease can spread is through excrement.
Bruce Kimball, a scientist in Colorado, USA, has been training mice to identify droppings from ducks with bird flu. During training sessions, Kimball's mice correctly picked out the feces, or poop, from infected ducks or nine times out of ten. Once the mice were trained, Kimball tested their new skills on new samples. In those trials, mice correctly picked out the droppings from sick birds 77 percent of the time.
Kimball and his team don't know exactly which chemical compounds the mice detect. The scientists suspect that when a bird is infected with bird flu, its immune system responds with certain chemicals. The mice may be responding to these chemicals in the feces of infected ducks.
Cockroaches welcome
Do you consider cockroaches nasty ? Do you pull out a slipper to throw as soon as you see one ? Think again, you may be thanking cockroaches soon, since they would be protecting you from many infectious diseases.
New research finds that the rudimentary brains of cockroaches and locusts teem with antimicrobial compounds that slay harmful E. coli and MRSA, the antibiotic-resistant staph bacterium. If you don't understand all that, don't worry: it only means that they can probably be used to make strong medicines for us.
When you see insects living in filthy places like drainage and sewers, and crawling on dead tissue, have you wondered how they can cope with all the bacteria ? This is the question that led scientist Naveed Khan and his team in Nottingham, England, to study how insects ward off disease.
They ground up various body parts from both cockroaches and desert locusts that had been reared in the lab and incubated them for two hours with different bacteria. Leaving these mixtures overnight on petri dishes revealed that the extracts from brains and from locust thorax nerve tissue killed nearly 100 percent of the bacteria !
Curiously, extracts of insect fat, muscle and blood didn't bother the bacteria at all. Cockroaches and locusts often eat stuff loaded with microbes.
On the other hand, insect brain extracts didn't seem to bother human kidney or epithelial cells when grown with them in a lab dish. This suggests that these extracts may be bad for bacteria while leaving human cells unaffected. 
Research is now on to isolate the responsible compunds. Medicine using insect extracts are a long way off.
Such a soft dinosaur
A dinosaur with soft feathers ? Yes indeed, according to the September 9, 2010 issue of the famous science magazine Nature.
Paleontologist Francisco Ortega and his team from central Spain have described a carnivorous dinosaur species that has a strikingly unusual hump on its back and hints of featherlike appendages on its arms. The 125 million-year-old fossil suggests that feathers evolved in more primitive dinosaurs than previously thought.
Scientists found the nearly complete skeleton of Concavenator corcovatus, which means "the hunchback hunter from Cuenca," at a fossil site called Las Hoyas, in Cuenca, Spain, in 2003. After seven years of painstaking removal work on the dense limestone in which the fossil was exquisitely preserved, they have a description of the animal.
Concavenator belongs to a family of carnivore dinosaurs that walked on hind legs, had three main fingers at the end of each stub by arm and ripped through flesh with razorlike teeth. But its fossil sports two new features. Two of the dinosaur's vertebrae are longer than the rest, indicating that it had a tall hump on its back that wasn't very long.
Concavenator also has bumps on its forearm bones that look a lot like quill knobs seen on the wing bones of modern birds. This could mean that Concavenator had featherlike structures on its arms.
If such a primitive dinosaur was feathered, its many descendants were probably feathered as well. Perhaps, say some scientists, a third of all dinosaurs that we know of were feathered.
Erupting volcanoes -- on Mars !
Volcanoes erupting, water flowing. All this on Mars, in the recent past. Do you find that hard to believe ? Of course, when scientists say recent past they mean within the last 100 million years or so. Still, this is surprising.
The September 10, 2010 issue of the magazine Science reports on the most precise measurements ever taken of carbon dioxide in the Martian atmosphere, recorded by NASA's Mars Phoenix Lander during its five months of operation in 2008. Because carbon dioxide gas reacts strongly with both water and silicate rock, measuring the relative proportions of different isotopes of carbon and oxygen in the Martian atmosphere provides a record of the history of both materials on the planet. 
The finding suggests that Mars continually replenishes the carbon dioxide it loses with fresh material. The most likely source is carbon dioxide belched during volcanic eruptions, say Paul Niles (NASA Space Center, Houston, USA) and his team. If they are right, volcanic activity has been significant on Mars during the past 100 million years, the time scale over which carbon dioxide naturally exits the atmosphere. The picture shows a 3D image of Olympus Mons on Mars, the largest known volcano in the Solar system.
Some scientists are not convinced by this explanation, but admit that the data is intriguing.
Where is all the oil ?
We all heard and read about the disaster caused by the oil spill in the Gulf of Mexico in April this year. We have been assured that the spill has been plugged. But there's still a lot of oil in the water. Scientists are trying to find and remove it -- and that's a difficult process.
To summarise, on April 20, the Deepwater Horizon drilling platform exploded. It sank two days later. A long pipe connected the drilling platform to an oil well buried deep under the Gulf of Mexico. When the platform sank, the pipe crumpled and oil began to flow into the water.
Between April 20 and July 15, when the hole was plugged, an estimated 4.9 million barrels of oil escaped. Much of the oil has floated to the surface, but much has not -- leaving many scientists scratching their heads. Where has it gone?
In August, one US government team reported that 17 percent of the oil was collected directly from the top of the well before it made it to the water, that another 5 percent was burned off and 3 percent was skimmed off the surface. Other scientists disagree. They say that only about 10 percent of the oil had been removed from the water, and that another 10 percent may have evaporated. 
In August a team of scientists reported that it had mapped a giant plume, or cloud, of oil floating beneath the surface. This cloud was about as tall as a 50-floor building and more than two kilometres long. It was floating more than one KM beneath the surface, and the researchers say that's mysterious. Oil usually floats on top of water, but there may be many of these plumes crawling along, deep underwater.
Oil floats on water because it is less dense. So why isn't all the oil floating in the Gulf of Mexico? A mathematician named Roberto Camassa (North Carolina, USA) may have the answer. He says that if oil droplets are small enough, it doesn't matter that oil is less dense than water. Tiny droplets don't float or sink -- they move with the water. He has demonstrated this using mathematical models and computer simulations. We do not yet know whether this is what is happening in the Gulf of Mexico, but it is one good explanation.
--Compiled from several sources