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Michael Jackson is suffering from a rare lung condition and needs to undergo an emergency transplant operation, according to a report that continues to gain steam.
And his normally outspoken publicist hasn’t denied the allegations.
The King of Pop may even be fighting for his life, New York Times bestselling biographer Ian Halperin tells In Touch magazine and Britain’s Sunday Express newspaper.
Halperin, author of such tomes as “Love & Death: The Murder of Kurt Cobain” and “Stalking Britney: Under Siege With Britney Spears,” says Jackson has been diagnosed with Alpha 1-antitrypsin deficiency, an occasionally fatal genetic condition.
“He’s had it for years but it’s gotten worse,” Halperin told In Touch. “He needs a lung transplant but may be too weak to go through with it.
He also has emphysema and chronic gastrointestinal bleeding, which his doctors have had a lot of trouble stopping. It’s the bleeding that is the most problematic part. It could kill him.”
According to Halperin, Jackson “can barely speak” and is having trouble seeing: “The vision in his left eye is 95 percent gone.”
Jackson, who has lived largely out the public eye in recent years, shocked fans in July when he was photographed in wheelchair.
The 50-year-old also received help walking when stepped out in Los Angeles earlier this month wearing a Zorro-style face mask.
Jackson’s rep was unavailable for comment Sunday, but the singer’s brother Jermaine didn’t deny the reports, telling Fox News, “He’s not doing so well right now. This isn’t a good time.”
NASA’s Hubble Space Telescope has caught Jupiter’s moon Ganymede playing a game of “peek-a-boo.” In this crisp Hubble image, Ganymede is shown just before it ducks behind the giant planet.
Ganymede completes an orbit around Jupiter every seven days. Because Ganymede’s orbit is tilted nearly edge-on to Earth, it routinely can be seen passing in front of and disappearing behind its giant host, only to reemerge later.
Composed of rock and ice, Ganymede is the largest moon in our solar system. It is even larger than the planet Mercury. But Ganymede looks like a dirty snowball next to Jupiter, the largest planet in our solar system. Jupiter is so big that only part of its Southern Hemisphere can be seen in this image.
Hubble’s view is so sharp that astronomers can see features on Ganymede’s surface, most notably the white impact crater, Tros, and its system of rays, bright streaks of material blasted from the crater. Tros and its ray system are roughly the width of Arizona.
The image also shows Jupiter’s Great Red Spot, the large eye-shaped feature at upper left. A storm the size of two Earths, the Great Red Spot has been raging for more than 300 years. Hubble’s sharp view of the gas giant planet also reveals the texture of the clouds in the Jovian atmosphere as well as various other storms and vortices.
Astronomers use these images to study Jupiter’s upper atmosphere. As Ganymede passes behind the giant planet, it reflects sunlight, which then passes through Jupiter’s atmosphere. Imprinted on that light is information about the gas giant’s atmosphere, which yields clues about the properties of Jupiter’s high-altitude haze above the cloud tops.
A research team led by Professor Michael Chazan, director of the University of Toronto’s Archaeology Centre, has discovered the earliest evidence of our cave-dwelling human ancestors at the Wonderwerk Cave in South Africa.
Stone tools found at the bottom level of the cave â€” believed to be 2 million years old â€” show that human ancestors were in the cave earlier than ever thought before. Geological evidence indicates that these tools were left in the cave and not washed into the site from the outside world.
Archaeological investigations of the Wonderwerk cave â€” a South African National Heritage site due to its role in discovering the human and environmental history of the area â€” began in the 1940s and research continues to this day.
Using a combination of dating methods it has been possible to date the bottom level reached by Peter Beaumont in the front part of the cave to 2 million years ago.
A small number of very small stone tools have been recovered from excavations in this level. Geological evidence indicates that these tools were deposited in the cave by human ancestors, not washed into the site from the outside.
The combination of stone tools indicating the presence of human ancestors and the dating of the level leads to the conclusion that human ancestors (hominids) were in the cave 2 million years ago. This is the earliest evidence for intentional cave occupation by human ancestors.
There were a number of species of hominids in southern Africat 2 million years ago. The most likely candidate as the manufacturer of the stone tools found at Wonderwerk is Homo habilis.
The oldest known stone tools from sites in Ethiopia date to 2.4 million years. The Wonderwerk Cave discoveries are those close in age to the very earliest known stone tools and similar in date to the bottom levels at Olduvai Gorge.
How the site was dated
The deposits at Wonderwerk Cave built up over time so that the deeper one excavates the layers become older. The trick is to figure out exactly how old the levels are. We used two methods that together provide a secure date.
For Paleomagnetic Dating Hagai Ron of the Hebrew University took small samples of soil from the entire sequence (over fifty samples). These samples allow him to measure changes in he earthâ€™s magnetic field and to correlate the Wonderwerk sequence with a global timescale for changes in the magnetic field (known as reversals).
For Cosmogenic Burial Age Ari Matmon, also from the Hebrew University, took soil samples and carefully prepared them in the lab. He then sent these samples to an atomic accelerator in the United States where a procedure to measure isotopes, much like the method used in carbon dating, was carried out. Unlike carbon dating, Cosmogenic Burial Age dating can provide very old dates.
Why was this so difficult? Most well dated early sites are in East Africa where there are volcanic ash layers that can be dated using the Argon method. In southern Africa we lack these ash layers so that we need to develop new methods. The first use of Cosmogenic Burial Age dating in South Africa was at the Cradle of Humankind. Our results show the value of this method, particularly when combined with Paledating, for archaeological research both in the region and globally.
About Wonderwerk Cave
The Wonderwerk Cave is located in Northern Cape Province, South Africa between Danielskuil and Kuruman. The cave formed by water action in the Dolemite rocks of the Asbestos Hills. This rock formation is over 2 billion years old, some of the oldest rock on earth, so we do not know when exactly the cave formed.
The cave runs 130 meters from front to back. Wonderwerk discovered was discovered when local farmers dug up large parts of the cave in the 1940â€™s to sell the sediments for fertilizer. Subsequently a series of brief archaeological excavations began. Peter Beaumont of the McGregor Museum carried out major excavations at the site between 1978-1993.
A Princeton-led team of researchers has discovered an entirely new mechanism for making common electronic materials emit laser beams. The finding could lead to lasers that operate more efficiently and at higher temperatures than existing devices, and find applications in environmental monitoring and medical diagnostics.
“This discovery provides a new insight into the physics of lasers,” said Claire Gmachl, who led the study. Gmachl, an electrical engineer, is the director of the Mid-Infrared Technologies for Health and the Environment (MIRTHE) center. The phenomenon was discovered in a type of device called quantum cascade laser, in which an electric current flowing through a specially designed material produces a laser beam. Gmachl’s group discovered that a quantum cascade laser they had built generated a second beam with very unusual properties, including the need for less electrical power than the conventional beam. “If we can turn off the conventional beam, we will end up with a better laser, which makes more efficient use of electrical power,” said Gmachl.
The team that conducted the study includes Gmachl’s graduate student Kale Franz, who built the laser that revealed the new phenomenon, and Stefan Menzel, a graduate student from the University of Sheffield, UK, who unearthed the unique properties of the phenomenon during an internship at Princeton University last summer. The study was published online in Nature Photonics on Dec. 14.
The light emitted by a laser differs fundamentally from light produced by common sources such as the sun, fire, or electric lamps. According to the field of physics called quantum electrodynamics, light is made up of particles called photons. Common sources of light emit photons that are in a random order, like crowds milling about a busy marketplace. In contrast, photons in a laser are “in sync” with each other, like a music band marching in formation. This property, called coherence, allows laser light to shine in an intense, narrow beam of a single, very pure color.
One way to produce a laser beam is to pass an electric current through a semiconductor such as gallium arsenide. The electric current pumps energy into the material, forcing a large number of its electrons to a higher energy level than normal. Under certain conditions, these electrons drop to a lower level of energy, and emit the extra energy in the form of synchronized photons of light. This is the mechanism underlying lasers used in CD writers, laser pointers and other common electronic devices.
The laser used in the Princeton study is a special type called a quantum cascade laser. Built at Princeton University’s nanofabrication facility, the device is about one-tenth as thick as a human hair and 3 millimeters long. Despite its tiny size, it is made of hundreds of layers of different semiconductor materials. Each layer is only a few atoms thick. In this device, electrons “cascade” down through the layers as they lose energy and give off synchronized photons.
In an earlier study published in Applied Physics Letters in June 2007, Franz, Gmachl and others had reported that a quantum cascade laser they had built unexpectedly emitted a second laser beam of slightly smaller wavelength than the main one. Further studies by Menzel and others revealed that the second beam could not be explained by any existing theory of quantum cascade lasers. Unlike a conventional semiconductor laser, the second beam grew stronger as the temperature increased, up to a point. Further, it seemed to compete with the “normal” laser, growing weaker as the latter strengthened when more electric current was supplied. “It’s a new mechanism of light emission from semiconductor lasers,” said Franz.
To explain this mechanism, the researchers invoked a quantum property of electrons called momentum. In the conventional view of quantum cascade lasers, only electrons of nearly zero momentum participate in “lasing” (producing laser light). Further, a substantial number of electrons has to attain the same level of energy and momentum â€“ be in a so-called “quasi-equilibrium” condition — before they can participate in laser action. In contrast, studies by Gmachl’s group showed that the second laser beam originated from electrons of lower energy, but higher momentum that were not in equilibrium. “It showed, contrary to what was believed, that electrons are useful for laser emission even when they are in highly non-equilibrium states,” said Franz.
The new laser phenomenon has some interesting features. For instance, in a conventional laser relying on low momentum electrons, electrons often reabsorb the emitted photons, and this reduces overall efficiency. In the new type of laser, however, this absorption is reduced by 90%, said Franz. This could potentially allow the device to run at lower currents, and also makes it less vulnerable to temperature changes. “It should let us dramatically improve laser performance,” he said.
The device used in the study does not fully attain this level of performance, because the conventional, low-efficiency laser mechanism dominates. To take full advantage of the new discovery, therefore, the conventional mechanism would need to be turned off. The researchers have started to work on methods to achieve this outcome, said Franz.
Unlike other lasers, quantum cascade lasers operate in the mid- and far-infrared range, and can be used to detect even minute traces of water vapor, ammonia, nitrogen oxides, and other gases that absorb infrared light. As a result, these devices are finding applications in air quality monitoring, medical diagnostics, homeland security, and other areas that require extremely sensitive detection of different chemicals. The new discovery should help make these devices smaller, more efficient, and more sensitive, said Gmachl.
JPL, NASA – Researchers using a powerful instrument aboard NASA’s Mars Reconnaissance Orbiter have found a long-sought-after mineral on the Martian surface and, with it, unexpected clues to the Red Planet’s watery past.
Surveying intact bedrock layers with the Compact Reconnaissance Imaging Spectrometer for Mars, or CRISM, scientists found carbonate minerals, indicating that Mars had neutral to alkaline water when the minerals formed at these locations more than 3.6 billion years ago. Carbonates, which on Earth include limestone and chalk, dissolve quickly in acid. Therefore, their survival until today on Mars challenges suggestions that an exclusively acidic environment later dominated the planet. Instead, it indicates that different types of watery environments existed. The greater the variety of wet environments, the greater the chances one or more of them may have supported life.
‘We’re excited to have finally found carbonate minerals because they provide more detail about conditions during specific periods of Mars’ history,’ said Scott Murchie, principal investigator for the instrument at the Johns Hopkins University Applied Physics Laboratory in Laurel, Md.
The findings will appear in the 19 December issue of Science magazine and were announced Thursday at a briefing at the American Geophysical Union’s Fall Meeting in San Francisco.
Carbonate rocks are created when water and carbon dioxide interact with calcium, iron or magnesium in volcanic rocks. Carbon dioxide from the atmosphere becomes trapped within the rocks. If all of the carbon dioxide locked in Earth’s carbonates were released, our atmosphere would be thicker than that of Venus. Some researchers believe that a thick, carbon dioxide-rich atmosphere kept ancient Mars warm and kept water liquid on its surface long enough to have carved the valley systems observed today.
‘The carbonates that CRISM has observed are regional rather than global in nature, and therefore, are too limited to account for enough carbon dioxide to form a thick atmosphere,’ said Bethany Ehlmann, lead author of the article and a spectrometer team member from Brown University, Providence, R.I.
‘Although we have not found the types of carbonate deposits which might have trapped an ancient atmosphere,’ Ehlmann said, ‘we have found evidence that not all of Mars experienced an intense, acidic weathering environment 3.5 billion years ago, as has been proposed. We’ve found at least one region that was potentially more hospitable to life.’
The researchers report clearly defined carbonate exposures in bedrock layers surrounding the 1,489-kilometre-diameter (925-mile) Isidis impact basin, which formed more than 3.6 billion years ago. The best-exposed rocks occur along a trough system called Nili Fossae, which is 666 kilometres (414 miles) long, at the edge of the basin. The region has rocks enriched in olivine, a mineral that can react with water to form carbonate.
‘This discovery of carbonates in an intact rock layer, in contact with clays, is an example of how joint observations by CRISM and the telescopic cameras on the Mars Reconnaissance Orbiter are revealing details of distinct environments on Mars,’ said Sue Smrekar, deputy project scientist for the orbiter at NASA’s Jet Propulsion Laboratory in Pasadena, Calif.
NASA’s Phoenix Mars Lander discovered carbonates in soil samples. Researchers had previously found them in Martian meteorites that fell to Earth and in windblown Mars dust observed from orbit. However, the dust and soil could be mixtures from many areas, so the carbonates’ origins have been unclear. The latest observations indicate carbonates may have formed over extended periods on early Mars. They also point to specific locations where future rovers and landers could search for possible evidence of past life.
The Applied Physics Laboratory led the effort to build the Compact Reconnaissance Imaging Spectrometer for Mars and operates the instrument in coordination with an international team of researchers from universities, government and the private sector. JPL, a division of the California Institute of Technology, Pasadena, manages the Mars Reconnaissance Orbiter mission for the NASA Science Mission Directorate in Washington. Lockheed Martin Space Systems, Denver, is the prime contractor for the project and built the spacecraft.
Two giant plumes of hot rock deep within the earth are linked to the plate motions that shape the continents, researchers have found.
The two superplumes, one beneath Hawaii and the other beneath Africa, have likely existed for at least 200 million years, explained Wendy Panero, assistant professor of earth sciences at Ohio State University.
The giant plumes — or “superpiles” as Panero calls them — rise from the bottom of Earth’s mantle, just above our planet’s core. Each is larger than the continental United States. And each is surrounded by a wall of plates from Earth’s crust that have sunk into the mantle.
She and her colleagues reported their findings at the American Geophysical Union meeting in San Francisco.
Computer models have connected the piles to the sunken former plates, but it’s currently unclear which one spawned the other, Panero said. Plates sink into the mantle as part of the normal processes that shape the continents. But which came first, the piles or the plates, the researchers simply do not know.
“Do these superpiles organize plate motions, or do plate motions organize the superpiles? I don’t know if it’s truly a chicken-or-egg kind of question, but the locations of the two piles do seem to be related to where the continents are today, and where the last supercontinent would have been 200 million years ago,” she said.
That supercontinent was Pangea, and its breakup eventually led to the seven continents we know today.
Scientists first proposed the existence of the superpiles more than a decade ago. Earthquakes offer an opportunity to study them, since they slow the seismic waves that pass through them. Scientists combine the seismic data with what they know about Earth’s interior to create computer models and learn more.
But to date, the seismic images have created a mystery: they suggest that the superpiles have remained in the same locations, unchanged for hundreds of millions of years.
“That’s a problem,” Panero said. “We know that the rest of the mantle is always moving. So why are the piles still there?”
Hot rock constantly migrates from the base of the mantle up to the crust, she explained. Hot portions of the mantle rise, and cool portions fall. Continental plates emerge, then sink back into the earth.
But the presence of the superpiles and the location of subducted plates suggest that the two superpiles have likely remained fixed to the Earth’s core while the rest of the mantle has churned around them for millions of years.
Unlocking this mystery is the goal of the Cooperative Institute for Deep Earth Research (CIDER) collaboration, a group of researchers from across the United States who are attempting to unite many different disciplines in the study of Earth’s interior.
Panero provides CIDER her expertise in mineral physics; others specialize in geodynamics, geomagnetism, seismology, and geochemistry. Together, they have assembled a new model that suggests why the two superpiles are so stable, and what they are made of.
As it turns out, just a tiny difference in chemical composition can keep the superpiles in place, they found.
The superpiles contain slightly more iron than the rest of the mantle; their composition likely consists of 11-13 percent iron instead of 10-12 percent. But that small change is enough to make the superpiles denser than their surroundings.
“Material that is more dense is going to sink to the base of the mantle,” Panero said. “It would normally spread out at that point, but in this case we have subducting plates that are coming down from above and keeping the piles contained.”
CIDER will continue to explore the link between the superpiles and the plates that surround them. The researchers will also work to explain the relationship between the superpiles and other mantle plumes that rise above them, which feed hotspots such as those beneath Hawaii and mid-ocean ridges. Ultimately, they hope to determine whether the superpiles may have contributed to the breakup of Pangea.
This work was funded by the National Science Foundation.