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olar Array Retracted From Space Station
Mike Schneider, Associated Press
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Dec. 13, 2006 — NASA began retracting via remote control a 115-foot solar panel on the International Space Station Wednesday, likening the tricky task to folding a road map back up and stuffing it in the glove compartment.

The electricity-generating solar array served as a temporary power source aboard the orbiting outpost. NASA needed to move it out of the way so that a new, permanent pair of solar wings could rotate in the direction of the sun.

The folding-up began shortly before 1:30 p.m. EST and was expected to take about five hours. A crease developed when the array was about a quarter of the way retracted, forcing controllers and astronauts to stop work for about an hour. They eventually decided to release the array slightly in hopes the crease would smooth out.
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Because it had been six years since the array was last folded up, flight controllers and astronauts were not sure how easy it would be.

"It's kind of like folding a map up," space shuttle Discovery commander Mark Polansky radioed Mission Control after the crease appeared. "You start folding it and the folding goes the wrong way. ... There's nothing you can do to it other than pop it back in place or unfold it and try again."

NASA needed the old solar array to be retracted at least 40 percent to provide enough clearance for a pair of giant solar wings that were delivered by space shuttle Atlantis in September. The old array will be moved to another spot during a later shuttle mission.



The space agency hoped to fit the old array into a 21-inch-high box. If it didn't fold up properly, NASA had the option of using spacewalkers to manually retract it at another time.

Flight controllers also watched to see whether the silicone coating on the 32,800 solar cells flaked off as the array was folded up. It would look like a "small, little snowstorm" but would be no reason for concern, said Joel Montalbano, a space station flight director.

During two spacewalks on Thursday and Saturday, astronauts will rewire connectors from the old solar array to the new solar wings. Reconfiguring the power system will enable the station to provide electricity to laboratories that will be added to the structure over the next few years.
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NASA had the shuttle astronauts and space station crew members sleep in highly protected areas of the two spacecraft Tuesday night as a precaution against radiation from a solar flare eruption. Such measures are taken from time to time in space.

Genetic Defect Prevents Pain
Malcolm Ritter, Associated Press
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Dec. 13, 2006 —Scientists have identified a genetic defect that prevents some people from feeling any physical pain, while leaving them perfectly normal otherwise. Sound like a blessing? It's not.

In Thursday's issue of the journal Nature, scientists who found the gene describe six related children who have never felt pain in their lives because of the very rare disorder. The children come from three families with roots in northern Pakistan.

Their experience illustrates that pain is an important warning of injury, disease or danger that signals people to save themselves from further injury. Life without that signal, the report shows, is dangerous.
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Because the children felt no pain from biting themselves, for example, all six had injuries to their lips, some requiring later plastic surgery. Two had lost one-third of their tongues.

Most had suffered fractures or bone infections that were diagnosed only later on because of limping or lack of using a limb.

Some also had been scalded by boiling liquids or steam, or burned from sitting on radiators, said C. Geoffrey Woods, a geneticist at the Cambridge Institute for Medical Research in England. He and colleagues wrote the Nature report.

Woods had been asked to see another patient, a boy who took advantage of the condition by performing street theater, piercing his arms with knives and walking on burning coals. But the boy died before Woods saw him, after jumping off the roof of a house on his 14th birthday.

Detailed examinations of the six children showed that their nervous systems appeared otherwise normal. They could perceive touch, warm and cold, tickle and pressure, for example.

DNA from the children and their parents was used to track down the genetic defect, which sabotages the ability of a protein to perform a key job in pain signaling.

Medical journals have recorded only a handful of people with a lifelong inability to feel pain. The first report was apparently in 1932, about a patient who made a living as a human pincushion act. A crucifixion had to be canceled after a spike was driven through one hand, because a woman in the audience fainted.

It's not clear whether any of the previously reported cases were caused by the newly identified genetic defect, Woods said. Nor is it clear how many people have this defect, although it's probably very rare, he added.

Still, knowledge about the defect and its impact might help scientists develop better painkillers, he and colleagues suggested.

lzheimer's Mark Traced in Spinal Fluid
Lauran Neergaard, Associated Press
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Dec. 12, 2006 — Scientists appear to have found a fingerprint of Alzheimer's disease lurking in patients' spinal fluid, a step toward a long-awaited test for the memory-robbing disease that today can be diagnosed definitively only at autopsy.

Researchers at New York's Weill Cornell Medical College discovered a pattern of 23 proteins floating in spinal fluid that, in very preliminary testing, seems to identify Alzheimer's — not perfectly, but with pretty good accuracy.

Far more research is needed before doctors could try spinal-tap tests in people worried they have Alzheimer's, specialists caution.
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But the scientists already are preparing for larger studies to see if this potential "biomarker" of Alzheimer's, reported Tuesday in the journal Annals of Neurology, holds up.

"We're looking to an era in which the kinds of uncertainties that many patients and their families face about the diagnosis of Alzheimer's disease will no longer be a problem," predicts Dr. Norman Relkin, a neurologist and the study's senior researcher.

About 4.5 million Americans have Alzheimer's, a toll expected to more than triple by 2050 as the population grays. The creeping brain disease gradually robs sufferers of their memories and ability to care for themselves, eventually killing them. There is no known cure; today's drugs only temporarily alleviate symptoms.

Currently, doctors diagnose Alzheimer's mainly by symptoms. That makes early diagnosis particularly difficult, and even more advanced disease can be confused with other forms of dementia. Nor is there a good way to track the disease's progression, important both for decisions about patient care as well as in testing the effectiveness of new drugs.

Major research is under way to try to change that, including a $60 million study now under way to give brain scans to 800 older Americans and try to pin down the earliest brain changes associated with Alzheimer's.

At the same time, scientists also are hunting what they call biomarkers - signs of the disease in areas other than hard-to-test brain tissue.

"A valid biomarker for Alzheimer's disease is sorely needed," said Dr. Sam Gandy, a neuroscientist at Philadelphia's Thomas Jefferson University and spokesman for the Alzheimer's Association.

But the new protein pattern requires "rigorous validation" by other researchers to make sure it really is linked to Alzheimer's, he cautioned.


By hunting for one protein at a time, scientists have discovered a few other biomarker candidates in cerebrospinal fluid. But Relkin and colleagues at Cornell University expanded the hunt: Using a technology called proteomics, they simultaneously examined 2,000 proteins found in the spinal fluid of 34 people who died with autopsy-proven Alzheimer's, comparing it to the spinal fluid of 34 non-demented people.

What emerged were 23 proteins, many that by themselves had never been linked to Alzheimer's but that together formed a fingerprint of the disease.

Then the researchers looked for that protein pattern in the spinal fluid of 28 more people - some with symptoms of Alzheimer's or other dementia, some healthy. The test indicated Alzheimer's in nine of the 10 patients that doctors suspect have it, and incorrectly fingered three people.
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What's next? That huge brain-scanning study is collecting spinal fluid samples from some participants, and Relkin has begun talks with those researchers about testing his results.

At his own hospital, he's using the protein test in a study of an experimental Alzheimer's treatment to see if changes in the fingerprint may predict when the drug does or doesn't work.

Scientists believe that Alzheimer's begins its insidious brain attack years, even decades, before forgetfulness appears - and if so, there should be evidence of those changes in the spinal fluid, Relkin explained.

"The spinal tap gives people pause," he acknowledged, agreeing that a blood test would be easier. But, "in expert hands ... it's not much more traumatic than having blood taken."

Were the Pyramids Made With Concrete?
Rossella Lorenzi, Discovery News
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Dec. 8, 2006 — Concrete was poured to build the Great Pyramids about 5,000 years ago, according to controversial research, which suggests the ancient Egyptans predated the Romans by thousands of years as the inventors of concrete.

Michel Barsoum, professor of materials engineering at Drexel University in Philadelphia, and colleagues report in the current issue of the Journal of the American Ceramic Society that the pyramids were constructed with a combination of carved stones and blocks of limestone-based concrete.

The study, drawn on a research made in the mid-1980s by the French materials scientist, Joseph Davidovits, consists of a detailed examination of samples taken from the pyramids and their vicinity.
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The aim was to determine whether the pyramid materials are natural or synthetic.

"Davidovits proposed that the pyramid blocks were cast in situ, with a wet mix of limestone particles and a binder, tamped into molds," wrote the researchers.

In time, the French scientist claimed, the wet mix hardened into a concrete that featured the appearance and properties of native limestone.

But Davidovits' theory lacked hard evidence and was widely rejected by the Egyptologist community.

The longstanding belief is that the pyramids were built with blocks of limestone carved from nearby quarries. The blocks were cut to shape using copper tools, transported to the pyramid site and then hauled up huge ramps and set in place using wedges and levers.

Using scanning and transmission electron microscopy, Barsoum and his co-workers, Gilles Hug of the French National Aerospace Research Agency, and Adrish Ganguly of Drexel University, analyzed and compared the mineralogy of a number of pyramid samples with six different limestone samples from their vicinity.

They found that pyramid samples featured mineral ratios that did not exist in any known limestone sources.

"The most convincing argument is the presence of amorphous SiO2 (silica)," Barsoum told Discovery News. "In sedimentary rocks, the SiO2 is almost always crystalline."

He also noted that some samples of calcite and dolomite taken from pyramid samples featured water molecules trapped inside — again, he said, this is not a phenomenon found in nature.

The researchers believe that a limestone concrete, called a geopolymer, was used for, at most, 20 percent of the blocks — in the outer and inner casings and in the upper parts of the pyramids.

Davidovits, himself, tested a limestone-based concrete recipe at the Geopolymer Institute at Saint-Quentin.

He concluded that diatomaceous earth (a soil formed by the decay of tiny organisms called diatoms), dolomite and lime were mixed in water to produce a clay-like mixture. This was what the ancient Egyptians would have poured into wooden moulds at Giza to obtain concrete blocks in a few days.

Indeed, with this recipe, Davidovits produced a large concrete limestone block in ten days.

The researchers point out that pouring concrete would have spared the ancient builders from using steep ramps to push stones to the summit of the pyramids.

Zahi Hawass, chief of Egypt's Supreme Council of Antiquities, dismissed the theory as "unlikely."

He noted that concrete was widely used at the pyramids in modern restoration work, suggesting that team may have taken samples from these modern cuts.
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But Barsoum rejected such criticism.

"I would have to be a complete and utter fool to confuse Portland cement to what we saw," he said.

David Walker, a Columbia University geologist, said that Barsoum and colleagues have a strong case when considering the mineralogical constitution of the block chips they examined.

"Both sides in this controversy have good points. Some blocks are definitely natural and some are not," Walker said, adding that the mystery over how the ancient Egyptians may have poured concrete is "all the more intriguing.

Egyptians Living Near Tombs Agree to Go
Sierra Millman, Associated Press
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Dec. 4, 2006 — After six decades of wrangling, Egyptians living in the hills near Luxor have agreed to move out and give tourists and archaeologists access to nearly 1,000 Pharaonic tombs that lie beneath their homes, the government said Saturday.

Officials said most of 3,200 families in the brightly painted, mud-brick houses have agreed to pack up and move to a $32 million residential complex being built three miles away. No deadline for moving has been set and there is no target date for finishing the complex.

"Most of them want to leave and they demand to leave," said Rania Yusuf, a spokeswoman for Egypt's Supreme Council for Antiquities in Luxor.
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Only a few families continue to resist, "and they will leave, believe me," Yusuf said.

The government began trying to get the families to leave after World War II, but talks repeatedly bogged down. Many residents, who depend on Luxor's tourist business to earn livings, argued that new homes being offered were too small and didn't come with new jobs.

Over time, though, many grew tired of the standoff.

In an effort to preserve the ancient tombs, authorities prohibited the homeowners from adding to their residences or installing modern plumbing, which forced people to bring water uphill using donkeys.

Many people expressed happiness with the government's latest offer, which includes giving residents either new homes or plots of land in the complex that will include a market, police station, cultural center and schools.

"We are happy, but at the same time we are not happy, because we leave the best place here," said Nadia Mohammad Qassem, who is unsure of when she and her family will move.

The area being vacated is near the Valley of the Kings and its famous collection of well-preserved tombs that draw thousands of tourists daily to Luxor. Egyptians moved into the Theban hills after the arrival of European antiquity hunters in the late 18th and early 19th centuries, offering jobs to help excavate — and loot — artifacts.

Elina Paulin-Grothe, an archaeologist involved in tomb excavation, said the best way to preserve the artifacts below is to move the residents.

"This cannot continue and the population is growing too fast," she said.

Advocates for the residents said many resisted moving over the decades not because they didn't want to live in more modern homes but because they wanted to move on their own terms.

"I mean, nobody wants to live in those conditions when they know that most of Egypt doesn't live like that and the world has moved on," said Caroline Simpson, a former archaeologist who coordinates a small cultural exhibition on the hillside.

Despite the agreement, some people are bittersweet about giving up their hillside homes, no matter that their living conditions are poor.

"For me, I don't want to even imagine what it would look like. Without houses, it's a dead place," said Abdo Osman Daramali.

Ancient Tsunami Ravaged Three Continents
Rossella Lorenzi, Discovery News
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Dec. 4, 2006 — A volcano avalanche in Sicily thousands of years ago caused a gigantic tsunami, which engulfed the Mediterranean Sea and ravaged the coastline of three continents in less than four hours, according to geological evidence and computer simulations.

In a study entitled "The Lost Tsunami," published in the current issue of the journal Geophysical Research Letters, Maria Teresa Pareschi and colleagues at Italy's National Institute of Geophysics and Volcanology suggest that the tsunami might also have caused the mysterious abandonment of a Neolithic village along the coast of present-day Israel.

Pareschi modeled the collapse of the eastern flanks of Mount Etna in the early Holocene (nearly 8,000 years ago), drawing a scenario in which six cubic miles of rock crashed into the water at a speed of 224 miles per hour.
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According to the simulation, waves splashed tremendously high near the landslide area and traveled as far as the coasts of Southern Europe, North Africa and Asia Minor.

"It is hard to find on-shore evidence of such a catastrophic event because since then the sea level has increased by about 10 meters (33 feet). But we found a wealth of submarine evidence across the floor of the Ionian Sea and the Sirte Abyssal Plains in Africa," Pareschi told Discovery News.

Indeed, the simulation showed that pressure from the ancient tsunami liquefied thick layers of soft

marine sediments across the Ionian seafloor and triggered a far-reaching underwater mudslide.

Holecene deposits in the Ionian Sea and the Gulf of Sirte in the form of so-called homogenite and megaturbidite deposits — both related to tsunami dynamics — would confirm the rapid and devastating event.


"Along the Calabrian coastline, the tsunami run-up wave reached heights of up to 40 meters (131 feet). The coasts of Greece and Libya were impacted by waves up to 13 meters (43 feet) high, while the coast of Egypt, Syria and Israel were inundated by two- to four-meter (six- to 13-foot) high waves," Pareschi said.

She believes that it is possible that the now submerged Neolithic village of Atlit-Yam in Israel was abandoned because of the Etna tsunami impact.

The village shows evidence of a sudden evacuation, including 6,000 fish that had been gutted and stored for future consumption and trade but then left to rot.
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Europe's top expert on volcano-generated tsunamis, geophysicist Stefano Tinti of Bologna University, described the study as interesting and credible, adding that the ancient event holds lessons for present-day dangers.

"Although there is absolutely no immediate risk for collapses similar to the one described by Pareschi, we should not forget the danger of island volcanoes," Tinto told Discovery News. "It is important to have constant monitoring and a tsunami warning system in the entire Mediterranean area."

Roman Emperor's Insignia Unearthed
Marta Falconi, Associated Press
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Dec. 4, 2006 — Archaeologists have unearthed what they say are the only existing imperial insignia belonging to Emperor Maxentius — precious objects that were buried to preserve them and keep them from enemies when he was defeated by his rival Constantine.

Excavation under Rome's Palatine Hill near the Colosseum turned up items including three lances and four javelins that experts said are striking for their completeness — digs usually turn up only fragments — and the fact that they are the only known artifacts of their kind.

Clementina Panella, the archaeologist who made the discovery, said the insignia were likely hidden by Maxentius' people in an attempt to preserve the emperor's memory after he was defeated by Constantine I in the 321 A.D. battle of the Milvian Bridge — a turning point for the history of the Roman empire which saw Constantine become the unchallenged ruler of the West.
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"Once he's lost, his objects could not continue to exist and, at the same time, could not fall in the hands of the enemy," she said Friday.

Some of the objects, which accompanied the emperor during his public appearances, are believed to be the base for the emperor's standards — rectangular or triangular flags, officials said.

An imperial scepter with a carved flower and a globe, and a number of glass spheres, believed to be a symbolic representation of the earth, also were discovered.

The discovery was announced Wednesday by Italy's Culture Minister Francesco Rutelli during a visit to New York.

The items, inside wooden boxes and wrapped in linen and silk, were found buried at a sanctuary last year and have since been restored and analyzed. The depth of the burial allows experts to date them to the early 4th century A.D., ministry officials said.

"These artifacts clearly belonged to the emperor, especially the scepter, which is very elaborated, it's not an item you would let someone else have," Panella said.

"As far as we know, there are no similar findings," said Angelo Bottini, the state's top official for archaeology in Rome. "Similar representations are only on coins and paintings, but we never saw them for real," he said. Bottini added that the artifacts will be shown to the public in February.
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Darius A. Arya, an archaeologist and professor at the American Institute for Roman Culture, said the discovery was highly unusual.

"Here's something precious that represents the greatness of Maxentius, buried by his loyal people to save something that belonged to him," said Arya, who was not involved in the excavation. "All together, they represented the power of this particular emperor and you wouldn't want the enemy or the usurper to get a hold of it."

Excavations on the Palatine in recent decades have turned up wonders such as the house of Rome's first emperor, Augustus. Experts said that much has yet to be uncovered, hidden in underground passageways.

Robot to Probe Cheops Pyramid
AFP
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Nov. 30, 2006 — A robot archaeologist is to be sent deep inside Egypt's largest pyramid in a bid to solve secrets revealed by a first foray more than four years ago, antiquities supremo Zahi Hawass said.

"The new robot will be sent down very narrow passages in the so-called Queen's Chamber, where the first robot was sent in 2002," said Hawass, who heads Egypt's Supreme Council of Antiquities.

Teams from Egypt and Singapore and a joint group from Britain and Hong Kong plan to insert the robot in February inside the Pyramid of Cheops at Giza, near to Cairo.
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Equipped with tiny cameras, the robot will be sent down the chamber's north and south passages in the hope of discovering what lies behind two inner walls — or doors — revealed during the first robotic expedition in September 2002.

At the time, the robot was sent into a northern shaft leading from the Queen's Chamber, only to be blocked about 65 yards from the chamber by "a stone wall or door" with copper handles.

It also revealed the existence of a similar obstruction the same distance down the south passage.

The robot drilled a tiny hole through this blockage that was large enough to insert a micro camera which showed a cavity filled with stones — itself closed on the far side by another wall or door.

Archaeologists have always hoped to find clues that might lead them to discover the tomb of Cheops himself. The pharaoh reigned more than 2,500 years before Christ, and it he was he who had the largest pyramid in Egypt built.
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Stonehenge Once a Healing Sanctuary?
Rossella Lorenzi, Discovery News
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Nov. 30, 2006 — Stonehenge might have been seen as a healing destination for ailing Neolithic and Bronze Age pilgrims, according to a new investigation into the megalithic monument.

Thought to have been built around 2700 B.C., the ring of standing stones has long puzzled scholars. Theories on its origins range from the possibility that it served as a mortuary to it being designed for human sacrifice or astronomy.

But according to Timothy Darvill, professor of archaeology at Bournemouth University in southern England, Stonehenge "was a sanctuary that served as an oracle and a place of pilgrimage for the sick."
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Darvill, who has detailed his findings in the book "Stonehenge: The Biography of a Landscape," suggests that the key to understanding Stonehenge lies in the Preseli Mountains in western Wales.

There he and colleague Geoffrey Wainwright located the quarry where the bluestones forming Stonehenge's inner circle were cut around 2500 B.C.

Weighing about 4 tons and standing between 6 and 9 feet tall, the blue-grey stones had to be transported 240 miles to the Stonehenge site in Wiltshire, England. According to Darvill, they were carried so far because they were regarded as holy.

"It was believed that the bluestones had many healing properties because in Preseli there are many sacred springs that are considered to have health-giving qualities," Darvill told Discovery News.

The belief that the stones held special power survived into the late 18th century, when many people went to Stonehenge to break off bits of rock as talismans.

Other evidence for his argument is found in the burial sites at Stonehenge, Darvill said.

"Amongst these burials, there seem to be a good proportion of people who show signs of being unwell — they would have walked with a limp or had broken bones and so on — just the sort of thing that in modern times pressures people to seek help from the Almighty," he explained.