Science & Technology


US: Scientists Grow Viable Urethras From Boys' Cells

Researchers have used patients' own cells to grow urinary tubes in the lab and have successfully used them to replace damaged tissue in five young boys, showing the potential power of cell-based therapies.

Urine flow tests and tube diameter measurements show the tissue-engineered urethras are still working after six years, said Dr. Anthony Atala, director of the Institute for Regenerative Medicine at Wake Forest University Baptist Medical Center in North Carolina.

The study, published on Monday in the journal Lancet, represents a first in the growing field of regenerative medicine, which doctors hope will eventually lead to ways to repair injuries and eventually replace whole organs.

"Totally grown in the laboratory, these urethras -- living tubes which convey urine from the bladder -- highlight the power of cell-based therapies," Chris Mason, a regenerative medicine expert at University College London who was not involved in the research, said in an e-mailed statement.

"When an organ or tissue is irreparably damaged or traumatically destroyed, no amount of drugs or mechanical devices will restore the patient back to normal," but he said cell-based therapies offer a potential cure.

Defective urethras can result from injury, disease or birth defects. While short defects in the tube can be repaired, larger defects are treated with a tissue graft, usually taken from skin or the lining of the cheek.

But these grafts fail in half of the cases, often leading to infection, pain, bleeding and trouble urinating.

Scientists Dubious Over Claim of Alien Life Evidence in Meteorite

Alien Life
© Hoover/Journal of Cosmology
Filaments in the Orgueil meteorite, seen under a scanning electron microscope, could be evidence of extraterrestrial bacteria, claims NASA scientist Richard Hoover.

The recent announcement by a NASA scientist of evidence for alien life in meteorites from outer space has created a firestorm of controversy that researchers say is unlikely to die down anytime soon.

The claim, announced Friday (March 4), called "startling, paradigm busting research," by the Journal of Cosmology, which published the findings, has been derided by critics, one of which referred to it "garbage."

The finding

Astrobiologist Richard Hoover of NASA's Marshall Space Flight Center in Huntsville, Ala., used scanning electron microscopes to analyze slices of carbonaceous meteorites that fell to Earth from space.

Based on the appearance of "filaments" and other features that resemble microbes, Hoover argues that the meteorites contain fossilized life in the form of cyanobacteria - single-celled organisms also known as blue-green algae. He supports this claim by presenting evidence of chemical compounds present in the meteorites that are consistent with a biological origin.
Grey Alien

NASA Scientist Finds 'Alien Life' Fossils

© Agence France-Presse
Activists dressed up as aliens from environmental watchdog Greenpeace demonstrate in Manila in 2009. A NASA scientist's claim that he found tiny fossils of alien life in the remnants of a meteorite has stirred both excitement and skepticism, and is being closely reviewed by 100 experts
A NASA scientist's claim that he found tiny fossils of alien life in the remnants of a meteorite has stirred both excitement and skepticism, and is being closely reviewed by 100 experts.

Richard Hoover's paper, along with pictures of the microscopic earthworm-like creatures, were published late Friday in the peer-reviewed Journal of Cosmology, which is available free online.

Hoover sliced open fragments of several types of carbonaceous chondrite meteorites, which can contain relatively high levels of water and organic materials, and looked inside with a powerful microscope.

He found bacteria-like creatures that he calls "indigenous fossils," which he believes originated beyond Earth and were not introduced here after the meteorites landed.

"He concludes these fossilized bacteria are not Earthly contaminants but are the fossilized remains of living organisms which lived in the parent bodies of these meteors, e.g. comets, moons, and other astral bodies," said the study.
Bizarro Earth

No such thing as a dormant volcano: Magma chambers awake sooner than thought

Crater of Mount Pinatubo
© iStockphoto/Arnel Manalang
Crater of Mount Pinatubo in the Philippines. Is there no such thing as a dormant volcano?
Until now it was thought that once a volcano's magma chamber had cooled down it remained dormant for centuries before it could be remobilized by fresh magma. A theoretical model developed by Alain Burgisser of the Orléans Institute of Earth Sciences (Institut des Sciences de la Terre d'Orléans -- CNRS/Universités d'Orléans et de Tours) together with a US researcher , was tested on two major eruptions and completely overturned this hypothesis: the reawakening of a chamber could take place in just a few months. This research should lead to a reassessment of the dangerousness of some dormant volcanoes.

It is published in the journal Nature dated 3 March 2011.

A magma chamber is a large reservoir of molten rock (magma) located several kilometers beneath a volcano, which it feeds with magma. But what happens to the magma chamber when the volcano is not erupting? According to volcanologists, it cools down to an extremely viscous mush until fresh magma from deep inside Earth 'reawakens' it, in other words fluidizes it by heating it through thermal contact. The large size of magma chambers (ranging from a few tenths to a few hundred cubic kilometers) explains why, according to this theory, it takes several hundred or even thousand years for the heat to spread to the whole reservoir, awakening the volcano from its dormant state.
Bizarro Earth

Blind Science: Humans in the Midst of Causing Planet's Sixth Mass Extinction

© Nature/University of California, Berkley
We're slowly creeping towards levels of mass extinction (see lines to the right), according to a recent study. Only five mass extinctions have occurred in the Earth's history and this one would the first caused directly by man.
Evolution will likely overcome the role of humanity, but pressure is unlike any in history

A mass extinction is a world-changing event. In order to qualify, 75 percent of species must be eliminated within a "short" period (between a few hundred thousand years to a few million years).

This has only happened five times in history, and according to researchers at the University of California, Berkley, it's happening a sixth time. This time, they claim humans are to blame.

The worst mass extinction in history occurred during the Permian Period, when most land species perished. While that won't likely happen, the majority of non-domesticate large land species may perish over the next a thousand years if mankind doesn't change its behavior, according to the researchers.

Anthony Barnosky, the curator of the Museum of Paleontology at UC Berkeley and another co-author of the study, comments that species go extinct today just as they have always. However, the real question is, "Is the pace of extinction we're seeing today over these short time intervals usual or unusual?"

Comment: For a better perspective as to why most of the above doesn't ring true, you are invited to read the following articles:

Cyclones, Earthquakes, Volcanoes And Other Electrical Phenomena

Fire and Ice: The Day After Tomorrow

Procession of the Damned: Mass Bird and Fish Deaths Turning Up Everywhere

Global Warming And The Corruption Of Science


Human Astrocytes Used to Repair Spinal Cord Injuries in Rats

Researchers are working to apply the cells to human models
© Stephen Davies
BMP transplants provide protection of spinal cord neurons while CNTF transplants do not

Researchers from the University of Colorado School of Medicine and the University of Rochester Medical Center have found a way to repair damage to the nervous system of rats and help restore their locomotor function as well through the use of a particular type of human cell.

Chris Proschel, Ph.D., study leader and assistant professor of genetics at the University of Rochester Medical Center, along with Stephen Davies, Ph.D., associate professor in the Department of Neurosurgery at the University of Colorado School of Medicine, and a team of researchers, have discovered a human cell that is produced from stem cells and placed into spinal cord-injured rats in order to repair nerve damage and restore certain functions.

The type of human cells used were human astrocytes, which are support cells in the central nervous system. These particular human astrocytes used were generated from stem cells called human fetal glial precursor cells, which were isolated and exposed to signaling molecules that instructed "different astrocytic cell fate." This process, which consisted of switching on or off signals in cells, created two types of human astrocytes -- BMP (bone morphogenetic protein) and CNTF (ciliary neurotrophic factor). One of the astrocytes was able to aid in the recovery of rats with spinal cord injuries while the other did not.

Michelangelo's David 'could collapse due to high-speed train building'

Michelangelo's statue of David is at risk of being toppled by the construction of a high-speed railway line beneath Florence because of his flimsy ankles.

The statue is riddled with tiny cracks, particularly in the ankles of the boy warrior, and could collapse as a result of vibrations from the 1.4 billion euro project, which is due to start in the summer.

The threat of serious damage being done to one of the world's most famous statues has prompted calls for it to be moved to a purpose-built museum away from the construction work.

"The tunnel will pass about 600 meters (2,000ft) from the statue of David, the ankles of which, it is well known, are riddled with micro-fissures. If it's not moved before digging begins, there is a serious risk that it will collapse," said Fernando De Simone, an expert in underground engineering.

The cracks in the marble are mostly in David's left ankle and in the carved tree stump which bears part of the statue's weight.

Inglorious take-off for NASA's research satellite as it plunges into the sea

© AP Photo/NASA
This image provided by NASA shows the encapsulated Glory spacecraft sitting atop the Taurus XL rocket and awaiting launch on the pad at Vandenberg Air Force Base's Space Launch Complex in Calif., Feb. 22, 2011. Vandenberg Air Force Base officials say the Taurus XL rocket carrying NASA's Glory satellite lifted off about 2:10 a.m. PST Friday from the base. However the fairing surrounding the Glory spacecraft failed to separate properly preventing the spacecraft from reaching orbit.
For the second time in two years, a rocket glitch sent a NASA global warming satellite to the bottom of the sea Friday, a $424 million debacle that couldn't have come at a worse time for the space agency and its efforts to understand climate change.

Years of belt-tightening have left NASA's Earth-watching system in sorry shape, according to many scientists. And any money for new environmental satellites will have to survive budget-cutting, global warming politics and, now, doubts on Capitol Hill about the space agency's competence.

The Taurus XL rocket carrying NASA's Glory satellite lifted from Vandenberg Air Force Base in California and plummeted to the southern Pacific several minutes later. The same thing happened to another climate-monitoring probe in 2009 with the same type of rocket, and engineers thought they had fixed the problem.

"It's more than embarrassing," said Syracuse University public policy professor Henry Lambright. "Something was missed in the first investigation and the work that went on afterward."

Squishy ice shifts climate models, study says

This satellite view shows Antarctica, which is covered by two ice sheets divided by the Transnatarctic Mountains. A new study found that a plateau just east of the mountain range includes ice that thaws and freezes over time, changing the structure of the ice sheet.
Knowing how the massive ice sheets atop Antarctica and Greenland work is key to predicting how global warming could raise sea levels and flood coastal cities. But a new study upends what scientists thought they knew. It turns out it's not just ancient snow that makes up the ice sheets, but water deep under the sheets also thaws and refreezes over time.

To put it in non-scientific terms, lead scientist Robin Bell told, the study redefines "how squishy" the base of ice sheets can be. "This matters to how fast ice will flow and how fast ice sheets will change."

"It also means that ice sheet models are not correct," she said, comparing it to "trying to figure out how a car will drive but forgetting to add the tires. The performance will be very different if you are driving on the rims."

Reporting in this week's issue of the peer-reviewed journal Science, Bell and his team described how ice-penetrating radar peeled back two miles of ice a million years old in the center of Antarctica.

Reduced Solar Activity Could Hint at Future

Sunspots represent magnetic activity on the surface and interior of the sun and have a cycle that averages 11 years. The 2008 minimum was the lowest in a century.

As a result, solar flares were almost nonexistent, and solar extreme ultraviolet radiation was at low ebb.

When solar extreme ultraviolet activity is low, it causes the thermosphere of Earth's atmosphere to shrink, and the contraction that took place in 2008-09 was the greatest in nearly 50 years.

Due to decreased atmospheric drag, the shrinking thermosphere changed the orbits of satellites.

During the same interval, the solar wind pressure was the weakest in 50 years, following a decreasing trend that began in the 1990s.

The solar wind permeates the entire solar system and creates the heliosphere, a bubble of magnetism originating from the sun and inflated by the solar wind. The entire solar system is inside the magnetic bubble. It is the first line of defense against cosmic rays.

In 2009 cosmic rays increased 19 percent over the highest seen in the past 50 years. The atmosphere protects us, but the increase created a danger for astronauts and satellites.

A whole fleet of spacecraft is devoted to solar physics. Monitoring the sun's vibrating surface allows helioseismologists to probe the stellar interior.

An article published in Nature yesterday revealed a new computer model of the sun's interior showing that plasma currents deep inside the sun interfered with the formation of sunspots and prolonged the solar minimum.

Like Earth, the sun has surface currents that run from the equator to the poles, then plunge deep beneath the surface and travel back to the poles.