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Evolutionary trait in pathogen cryptococcus gattii allows it to bypass strong immune responses

New research into a rare pathogen has shown how a unique evolutionary trait allows it to infect even the healthiest of hosts through a smart solution to the body's immune response against it.

Scientists at the University of Birmingham have explained how a particular strain of a fungus, Cryptococcus gattii, responds to the human immune response and triggers a 'division of labour' in its invading cells, which can lead to life-threatening infections.

Once inhaled, the pathogen can spread through the body to cause pneumonia or meningitis. The outbreak strain of this fungus differs significantly from other strains because it threatens the lives of healthy people -- those with a strong immune response -- rather than those usually considered at risk of infection.

Professor Robin May, from the University of Birmingham, explained, "It is important to point out that the risk to any individual is still very low: the fungus is non-contagious and cannot be passed between humans, or indeed from animals to humans, so we're not presenting a doomsday scenario here."
Cloud Grey

'Space Bubbles' may have downed key Afghan rescue mission

helicopter
© news.agu.org
Soldiers walk to the ramp of the CH-47 Chinook helicopter that will return them to Kandahar Army Air Field. New models will help predict the impact of plasma bubbles on future missions.
Twelve years ago, a U.S. military rescue mission in Afghanistan went horribly wrong. A Chinook helicopter carrying U.S. troops failed to receive a crucial radio message and was shot down over the snow-covered peak of Takur Ghar.

But the radio failure was not caused by malfunctioning equipment. Instead, a giant, 62-mile-long (100 kilometers) "plasma bubble" made up of clouds of electrically charged particles was responsible for the communication blackout, new research suggests.

Michael Kelly, a researcher at the Johns Hopkins University Applied Physics Lab (APL), in Laurel, Maryland, started to put the pieces together after reading a journalist's account of the Battle of Takur Ghar. He suspected the radio failure was caused by a little-known space weather effect caused by these mysterious plasma bubbles.

Ionospheric Scintillation
© www.jhuapl.edu
Plasma Bubbles: Tendrils of low-density charged particles with turbulence at their edges can skew radio frequency waves passing through them.
During daylight hours in the upper atmosphere, radiation beaming down from the sun rips electrons from their atoms. But once the sun sets, the electrons start recombining with their atoms. This recombination process happens faster in the lower atmosphere because there are heavier particles there, and electrons recombine faster with molecules than they do with single atoms. Since the plasma in this part of the atmosphere is less dense, it rises and burrows into the denser plasma above. This causes giant bubbles of charged particles to form, similar to the way air bubbles rise from a submerged diver.

Comment: The data for this research was from the Global Ultraviolet Imager(GUVI) instrument aboard NASA's Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) mission, which launched in 2001 to study the composition and dynamics of the upper atmosphere. A new model, based on this data, shows the electron-depleted regions of the atmosphere where radio wave interference, known as scintillation, is most likely to occur. Bubbles have been tracked between 53 and 370 miles above the earth, perhaps answers to space weather communications blackouts.

Moon

Electric Universe: NASA's Cassini caught in Hyperion's particle beam

Hyperion
© Credit: NASA/JPL/Space Science Institute
This stunning false-color view of Saturn's moon Hyperion reveals crisp details across the strange, tumbling moon's surface. Differences in color could represent differences in the composition of surface materials. The view was obtained during Cassini's close flyby on Sept. 26, 2005. Hyperion has a notably reddish tint when viewed in natural color. The red color was toned down in this false-color view, and the other hues were enhanced, in order to make more subtle color variations across Hyperion's surface more apparent.
Static electricity is known to play an important role on Earth's airless, dusty moon, but evidence of static charge building up on other objects in the solar system has been elusive until now. A new analysis of data from NASA's Cassini mission has revealed that, during a 2005 flyby of Saturn's moon Hyperion, the spacecraft was briefly bathed in a beam of electrons coming from the moon's electrostatically charged surface.

The finding represents the first confirmed detection of a charged surface on an object other than our moon, although it is predicted to occur on many different bodies, including asteroids and comets.

The new analysis was led by Tom Nordheim, a doctoral candidate at Mullard Space Science Laboratory (MSSL), University College London, and was published recently in the journal Geophysical Research Letters.

Hyperion is porous and icy, with a bizarre, sponge-like appearance. Its surface is continuously bombarded by ultraviolet light from the sun and exposed to a rain of charged particles - electrons and ions - within the invisible bubble generated by Saturn's magnetic field, called the magnetosphere. The researchers think Hyperion's exposure to this hostile space environment is the source of the particle beam that struck Cassini.

Comment: The Electric Universe theory and much more are discussed in Pierre Lescaudron and Laura Knight-Jadczyk's new book, Earth Changes and the Human-Cosmic Connection.

For more information listen to:

SOTT Talk Radio show #70: Earth changes in an electric universe: Is climate change really man-made?

SOTT Talk Radio: The Electric Universe - An interview with Wallace Thornhill

Saturn

Solar-system-wide climate change: Scientists puzzled by 'wobble' of Saturn moon Mimas

Mimas
© NASA/JPL l
Cassini image of Mimas, the closest of Saturn’s regular moons.
'Something is not right' with Saturn's 'Death Star'

An interesting recent space study found that one of Saturn's moons is behaving in a way scientists weren't expecting to see:
Mimas, one of Saturn's moons (nicknamed 'Death Star') has a telltale 'wobble', according to a new study.

"The data suggest that something is not right," Dr.Radwan Tajeddine, a Cornell University research associate in astronomy and the lead author of the article, said in a statement by NASA's Jet Propulsion Laboratory (JPL). "The amount of wobble we measured is double what was predicted."

The Cassani research associate went into more detail about what was "not right."
Magnify

Microbial evolution: Primitive microbes stole bacterial genes

Archaea

In the late 1970s, the hot springs of Yellowstone National Park were among the first places that Archaea, a previously unsuspected domain of life, were discovered.
A University of Otago researcher is part of an international team that has discovered that horizontal gene transfer (HGT) played a surprisingly large role in the evolution of primitive microbes known as archaea.

HGT, which involves acquiring genetic material from another unrelated organism instead of inheriting it from a direct ancestor, is most known today for its role in antibiotic resistance and its use in genetic modification technologies.

The team's findings appear this week in the prestigious journal Nature and show that archaea have swiped dozens, and sometimes hundreds, of bacterial genes on numerous occasions. Their research shows that these gene transfers are a far more important mechanism of microbial evolution than had been previously thought.

Archaea, which live in environments ranging from boiling geysers to the human navel, are single-celled microbes representing one of the three domains of life. The other two are bacteria and eukaryotes (organisms whose cells have a nucleus, such as plants and animals).
Bulb

Italian company to revolutionize home building in poor countries with 3D-printed huts

WASP 3D printer

Photo from WASProject website
An Italian company believes they have come up with an idea that could improve the lives of hundreds of millions. They have developed an easily transportable printer that can build houses out of natural materials, such as mud or clay.

The technology is relatively simple, and was designed by the Italian based company, WASP (World's Advanced Saving Project), and one of its main attributes is it can be assembled in two hours.

The printer has three arms with a six-meter reach in height. So it can build houses to a much greater height than is usually the case with a mud hut. Another difference is the method of construction, which makes the dwelling much stronger. Instead of using large square blocks, small triangles are used, allowing the house to bear a much greater load.
Frog

Poisonous frogs evolve to sing longer and louder

Devil Frog
© Pete Oxford/NaturePL
Hear my song: but you'll regret it if you eat me.
He's sexy and he knows it. The little devil frog is noisy in pursuit of a partner, and doesn't care who hears him.

The little devil frog's fearlessness in the face of hungry predators could be down to his toxicity. The little devil, Oophaga sylvatica, is a member of the dendrobatid group of poisonous frogs. His bright colours warn predators that he is unsafe to eat, which Juan Santos of the University of British Columbia in Vancouver, Canada, believes has allowed the evolution of more flamboyant mating calls.

Santos and his colleagues examined the calls, colourings and toxicity of 170 species of frog, including the little devil. They found a strong relationship between the volume of a frog's call and its aposematism - markings that warn of its toxicity. In general, the more toxic a frog, the brighter and more noticeable it is - and the louder and more rapidly it sings (Proceedings of the Royal Society B). Non-toxic frogs are camouflaged and call from less exposed perches, says Santos.

"Females can have a significant effect on the selection of the most noisy males, given that predators will avoid these aposematic individuals," says Santos.
Magnify

Myelin vital for learning new practical skills

myelin
© Sarah Jolly, UCl
Image shows the complex shape of individual oligodendrocytes (OLs) and myelin in adult mice injected with tamoxifen.
New evidence of myelin's essential role in learning and retaining new practical skills, such as playing a musical instrument, has been uncovered by UCL research. Myelin is a fatty substance that insulates the brain's wiring and is a major constituent of 'white matter'. It is produced by the brain and spinal cord into early adulthood as it is needed for many developmental processes, and although earlier studies of human white matter hinted at its involvement in skill learning, this is the first time it has been confirmed experimentally.

The study in mice, published in Science today, shows that new myelin must be made each time a skill is learned later in life and the structure of the brain's white matter changes during new practical activities by increasing the number of myelin-producing cells. Furthermore, the team say once a new skill has been learnt, it is retained even after myelin production stops. These discoveries could prove important in finding ways to stimulate and improve learning, and in understanding myelin's involvement in other brain processes, such as in cognition.

For a child to learn to walk or an adult to master a new skill such as juggling, new brain circuit activity is needed and new connections are made across large distances and at high speeds between different parts of the brain and spinal cord. For this, electrical signals fire between neurons connected by "axons" -- thread-like extensions of their outer surfaces which can be viewed as the 'wire' in the electric circuit. When new signals fire repeatedly along axons, the connections between the neurons strengthen, making them easier to fire in the same pattern in future. Neighbouring myelin-producing cells called oligodendrocytes (OLs) recognise the repeating signal and wrap myelin around the active circuit wiring. It is this activity-driven insulation that the team identified as essential for learning.
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Brain's compass relies on geometric relationships, say researchers

layouts
© Penn News
Each of the virtual museums in the study was visually distinct, but had the same layout and geometry.
The brain has a complex system for keeping track of which direction you are facing as you move about; remembering how to get from one place to another would otherwise be impossible. Researchers from the University of Pennsylvania have now shown how the brain anchors this mental compass.

Their findings provide a neurological basis for something that psychologists have long observed about navigational behavior: people use geometrical relationships to orient themselves.

The research, which is related to the work that won this year's Nobel Prize in Physiology or Medicine, adds new dimensions to our understanding of spatial memory and how it helps us to build memories of events.

The study was led by Russell Epstein, a professor of psychology in Penn's School of Arts & Sciences, and Steven Marchette, a postdoctoral fellow in Epstein's lab. Also contributing to the study were lab members Lindsay Vass, a graduate student, and Jack Ryan, a research specialist.

It was published in Nature Neuroscience.
Beaker

Could designer viruses be the new antibiotic?

Bacteria
© Credit: Graham Beards/Wikimedia Commons
Bacteria under attack by a flock of bacteriophages.
Bacterial infections remain a major threat to human and animal health. Worse still, the catalogue of useful antibiotics is shrinking as pathogens build up resistance to these drugs. There are few promising new drugs in the pipeline, but they may not prove to be enough. Multi-resistant organisms - also called "superbugs" - are on the rise and many predict a gloomy future if nothing is done to fight back.

The answer, some believe, may lie in using engineered bacteriophages - a type of viruses that infects bacteria. Two recent studies, both published in the journal Nature Biotechnology, show a promising alternative to small-molecule drugs that are the mainstay of antibiotics today.
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