miércoles, 27 de octubre de 2010
Photograph by Cris Bouroncle, AFP/Getty Images
A rare undisturbed tomb atop an ancient pyramid in Lima, Peru, has yielded four 1,150-year-old, well-bundled mummies of the Wari culture, archaeologists announced on October 20.
The mummies include what appear to be an elite woman and three children, who may have been sacrificed to accompany her into the afterlife, according to Isabel Flores Espinosa, excavation director at the Huaca Pucllana archaeological site.
The Wari civilization spread along the central coast of Peru beginning around A.D. 700. At Huaca Pucllana, they replaced the Lima culture before being replaced themselves by the ascendant Inca.
Mask of the Mummy
Photograph by Cris Bouroncle, AFP/Getty Images
Wrapped in layers of fabric and vegetation, mummies of an apparently elite Wari woman and a likely child sacrifice are exposed in Lima's mud-brick Huaca Pucllana pyramid on October 20.
Though the mummy bundles' fake heads—made of cloth or carved from wood—appear well preserved, "the state of the bodies inside might be only bones or partially dried-out bodies," Espinosa said in an email translated from Spanish.
Pyramid Looming Over Lima
Photograph by Enrique Castro-Mendivil, Reuters
Excavation work continues at the pyramid at the center of the Huaca Pucllana archaeological site in the Peruvian capital. Prior to occupation by the Wari, the eight-story-tall monument was a ceremonial center for the Lima culture, for which the surrounding city is named.
In addition to the undisturbed tomb containing the mummies, archaeologists have discovered 61 other Wari mummy bundles at the site, though each had been subject to looting. The newfound, undisturbed crypt should allow a reconstruction of the entire Wari funerary complex believed to exist here, Espinosa said.
Photo: A historic portrait of Pocahontas in London, age 21, dressed as the Christian lady she had become. She died within months. This portrait hangs in the National Portrait Gallery of the Smithsonian, in Washington, D.C.
A team of archaeologists believe they may have finally discovered Pocahontas' wedding site, a mystery that has long vexed scholars.
Her matrimonial location may sound more modern than one would expect for a 1614 marriage between a 19-year-old daughter of an American Indian chief and her tobacco farmer husband.
Archaeologist Bill Kelso and his team discovered the church in a previously unexplored area of the fort in Jamestown, Virg. During a dig, they unearthed a series of deep holes. They believe the holes were once filled with wood columns that supported the fort's first church, built in 1608.
Kelso, the director of archaeology at Historic Jamestowne, has spent decades excavating Jamestown, the first permanent English settlement in colonial America.
Remnants of the church are mostly now gone, but Kelso believes the site had 60-foot-long walls and a thatched roof.
A row of graves found near the altar was the clincher that convinced his team that they had indeed found the fort's church.
Historically, prominent Anglicans were buried in that part of the church, called the chancel.
The church was a major part of the settlers' lives. The large church was built in the center of the fort, so no one could pass through the site and miss it.
Some erroneously believed Pocahontas was romantically linked to Captain John Smith, most likely due to the Disney film inspired by her life. In fact, many scholars believe Smith's claims that Pocahontas saved his life after he was captured by the Powhatans to also be myth.
Pocahontas married the widowed John Rolfe in 1614 and bore him a son about nine months later. She died in England in 1617 at the age of 21. The cause of her death is still unknown.
Even as tornado watches remain in effect, meteorologists are shaking their heads at the "Superstorm" that savaged the Midwest Tuesday, spawning twisters and other damaging winds and breaking records for its hurricane-like intensity.
The middle latitudes of the Northern Hemisphere are often a meteorological battleground this time of year between the declining forces of the summer's warmth and the resurgent cold of impending winter, just as spring often sees violent clashes of opposing seasonal patterns.But what happened this week was different in magnitude if not in kind.
Crossing Minnesota late Monday and Tuesday, low atmospheric pressure sank to 955 millibars -- the kind of intensity readings that forecasters are more accustomed to seeing in the eyes of hurricanes.
Meteorologist Larry Cosgrove in Houston said that unofficially "this disturbance may have sported the lowest barometric pressure in recorded history."
Meteorologist Jeff Masters at Weather Underground said the pressure reading was "the lowest pressure ever measured anywhere in the continental United States aside from the Atlantic Coast."
Masters observed something else:
"Yesterday's superstorm is reminiscent of the amazing low pressures reached earlier this year (Jan. 19-22) in the West, where virtually every site in California, Nevada, Utah, Arizona, southern Oregon, and southern Idaho -- about 10-15 percent of the U.S. land area -- broke their lowest on record pressure readings..."
"We've now had two remarkable extratropical storms this year in the U.S. that have smashed all-time low pressure records across a large portion of the counter. Is this a sign that these type of storms may be getting stronger. Well, there is evidence that wintertime extratropical storms have grown in intensity in the Pacific, Arctic, and Great Lakes in recent decades."
Earlier this year, Masters wrote that modeling studies simulating an atmosphere with greater concentrations of greenhouse gases "predict a future with fewer total winter storms, but a greater number of intense storms."
IMAGE: Red Cross workers walk away from a barn that was lifted off its foundation by a tornado Oct. 26, 2010, in Mount Pleasant, Wis. Credit: AP
This year’s Los Angeles Auto Show Design Challenge tackles a heavy question: How do you build a lightweight car that doesn’t compromise safety, styling or performance?
Mercedes-Benz’s answer to that question involves a high-end rickshaw, a Smart knit by lovable robot grandmothers and a sedan grown from seeds. We swear these are concepts from Mercedes, not Citroën.
For the first time in its 7-year history, the Design Challenge expanded its reach beyond Southern California and invited Mercedes-Benz design studios from Japan and Germany to participate in the annual competition. As thanks for the invite, Mercedes brought concepts that stick out amidst relatively staid designs from General Motors, Honda and Nissan like Hammer Pants at the Highland Games.
This year’s rules stipulate that entries must weigh less than 1,000 pounds (1,500 with passengers). They’ll be judged by “artistic beauty, comfort, uniqueness of design, roadworthiness, sustainability, performance and user-friendliness of the vehicle.” We’re sure our commenters will weigh in on whether some of these avant-garde designs meet these criteria.
From Mercedes-Benz Research and Development Japan’s Advanced Design Center comes the Maybach DRS “Den-Riki-Sha” electric rickshaw. It’s more like a Rick-Segway, however, with a self-balancing electric drivetrain, albeit one that’s connected to a yet-to-be-developed intelligent transit infrastructure.
The Volk at Mercedes-Benz Advanced Advanced Design Germany might have been inspired by the theme of some trendy Berlin club for their Smart 454 design. The car is made of carbon fiber literally knit by “incredibly high-tech robots that look as friendly and cuddly as our grandmothers.” We imagine that cold, industrial robots only seem lifelike if your grandmother is Lucille Bluth.
Even Mercedes’ American designers offered a bizarre creation. The Biome concept is grown from two seeds that are genetically engineered to customer specifications. Cars are nurtured at Mercedes-Benz Nurseries until the two seeds grow into a seamlessly integrated interior and exterior. Even among the far-out ideas from Mercedes, this one is especially fanciful.
Though they’re highly advanced designs, the compressed-air cars from Honda and Volvo, the polyhedral 3-D lattice mono-formed frame of the Cadillac Aera, the ultralight Mazda MX-0 or the combination organic-synthetic exteriors that encapsulate concepts from Nissan and Calty Design Research seem tame compared with the oddball lightweights from Mercedes.
Judging ends Nov. 18. We’ll keep you posted.
Stable Way to Store the Sun's Heat: Storing Thermal Energy in Chemical Could Lead to Advances in Storage and Portability
Researchers at MIT have revealed exactly how a molecule called fulvalene diruthenium, which was discovered in 1996, works to store and release heat on demand. This understanding, reported in a paper published on Oct. 20 in the journal Angewandte Chemie, should make it possible to find similar chemicals based on more abundant, less expensive materials than ruthenium, and this could form the basis of a rechargeable battery to store heat rather than electricity.
The molecule undergoes a structural transformation when it absorbs sunlight, putting it into a higher-energy state where it can remain stable indefinitely. Then, triggered by a small addition of heat or a catalyst, it snaps back to its original shape, releasing heat in the process. But the team found that the process is a bit more complicated than that.
"It turns out there's an intermediate step that plays a major role," said Jeffrey Grossman, the Carl Richard Soderberg Associate Professor of Power Engineering in the Department of Materials Science and Engineering. In this intermediate step, the molecule forms a semi-stable configuration partway between the two previously known states. "That was unexpected," he said. The two-step process helps explain why the molecule is so stable, why the process is easily reversible and also why substituting other elements for ruthenium has not worked so far.
In effect, explained Grossman, this process makes it possible to produce a "rechargeable heat battery" that can repeatedly store and release heat gathered from sunlight or other sources. In principle, Grossman said, a fuel made from fulvalene diruthenium, when its stored heat is released, "can get as hot as 200 degrees C, plenty hot enough to heat your home, or even to run an engine to produce electricity."
Compared to other approaches to solar energy, he said, "it takes many of the advantages of solar-thermal energy, but stores the heat in the form of a fuel. It's reversible, and it's stable over a long term. You can use it where you want, on demand. You could put the fuel in the sun, charge it up, then use the heat, and place the same fuel back in the sun to recharge."
In addition to Grossman, the work was carried out by Yosuke Kanai of Lawrence Livermore National Laboratory, Varadharajan Srinivasan of MIT's Department of Materials Science and Engineering, and Steven Meier and Peter Vollhardt of the University of California, Berkeley.
The problem of ruthenium's rarity and cost still remains as "a dealbreaker," Grossman said, but now that the fundamental mechanism of how the molecule works is understood, it should be easier to find other materials that exhibit the same behavior. This molecule "is the wrong material, but it shows it can be done," he said.
The next step, he said, is to use a combination of simulation, chemical intuition, and databases of tens of millions of known molecules to look for other candidates that have structural similarities and might exhibit the same behavior. "It's my firm belief that as we understand what makes this material tick, we'll find that there will be other materials" that will work the same way, Grossman said.
Grossman plans to collaborate with Daniel Nocera, the Henry Dreyfus Professor of Energy and Professor of Chemistry, to tackle such questions, applying the principles learned from this analysis in order to design new, inexpensive materials that exhibit this same reversible process. The tight coupling between computational materials design and experimental synthesis and validation, he said, should further accelerate the discovery of promising new candidate solar thermal fuels.
Kepler Spacecraft Takes Pulse of Distant Stars: 'Starquakes' Yield New Insights About the Size, Age and Evolution of Stars
An international cadre of scientists that used data from NASA's Kepler spacecraft announced Tuesday the detection of stellar oscillations, or "starquakes," that yield new insights about the size, age and evolution of stars.
The results were presented at a news conference at Aarhus University in Denmark by scientists representing the Kepler Asteroseismic Science Consortium (KASC). The team studied thousands of stars observed by Kepler, releasing what amounts to a roster of some of humanity's most well-characterized stars.
Analysis of stellar oscillations is similar to how seismologists study earthquakes to probe the Earth's interior. This branch of science, called astroseismology, produces measurements of stars the Kepler science team is anxious to have.
"Using the unparalleled data provided by Kepler, KASC scientists are quite literally revolutionizing our understanding of stars and their structures," said Douglas Hudgins, Kepler Program Scientist at NASA Headquarters in Washington. "What's more, they are doing so at no cost to the American taxpayer. All the KASC scientists are supported by research funding from their home countries. It is a perfect illustration of the tremendous value that our international partners bring to NASA missions."
In the results presented Tuesday, one oscillating star took center stage: KIC 11026764 has the most accurately known properties of any star in the Kepler field. In fact, few stars in the universe are known to similar accuracy. At an age of 5.94 billion years, it has grown to a little over twice the diameter of the sun and will continue to do so as it transforms into a red giant. The oscillations reveal that this star is powered by hydrogen fusion in a thin shell around a helium-rich core.
"We are just about to enter a new area in stellar astrophysics," said Thomas Kallinger, lead author on a study of red giant stars and postdoctoral fellow at the Universities of British Columbia and Vienna. "Kepler provides us with data of such good quality that they will change our view of how stars work in detail."
KASC scientists also reported on the star RR Lyrae. It has been studied for more than 100 years as the first member of an important class of stars used to measure cosmological distances. The brightness, or light wave amplitude, of the star oscillates within a well-known period of about 13.5 hours. Yet during that period, other small cyclic changes in amplitude occur -- behavior known as the Blazhko effect. The effect has puzzled astronomers for decades, but thanks to Kepler data, scientists may have a clue as to its origin. Kepler observations revealed an additional oscillation period that had never been previously detected. The oscillation occurs with a time scale twice as long as the 13.5-hour period. The Kepler data indicates the doubling is linked to the Blazhko effect.
"Kepler data ultimately will give us a better understanding of the future of our sun and the evolution of our galaxy as a whole," said Daniel Huber, lead author on one of the KASC studies.
Launched in March 2009, Kepler was designed to discover Earth-size planets orbiting other stars. The spacecraft uses a huge digital camera, known as a photometer, to continuously monitor the brightness of more than 150,000 stars in its field of view as it orbits around the sun. Kepler searches for distant worlds by looking for "transits," when a planet passes in front of a star, briefly causing it to dim. The amount of dimming reveals the size of the planet compared to the size of the star.
In a short, violent battle that could have happened somewhere this afternoon, the lizard made a fast lunge at the dragonfly, bit its head off and turned to run away. Lunch was served.
But the battle didn't happen today, it happened about 100 million years ago, probably with dinosaurs strolling nearby. And the lizard didn't get away, it was trapped in the same oozing, sticky tree sap that also entombed the now-headless dragonfly for perpetuity.
This ancient struggle, preserved in the miracle of amber, was just described by researchers from Oregon State University in Paleodiversity, a professional journal. It announced the discovery of a new sub-family of dragonflies in the oldest specimen of this insect ever found in amber.
More importantly, the study and others like it continue to reveal the similarities of behaviors and ecosystems separated by many millions of years, said George Poinar, a professor emeritus at Oregon State University. Poinar is one of the world's leading experts on life forms found preserved in this semi-precious stone that acts as a natural embalming agent.
"Dragonflies are still eaten by small lizards every day, it's a routine predator/prey interaction," Poinar said. "This shows once again how behaviors of various life forms are retained over vast amounts of time, and continues to give us insights into the ecology of ancient ecosystems."
Dragonflies are one of the world's more colorful, interesting and successful insects, Poinar said, having managed to survive for a very long time. This is the oldest fossil ever found in amber, but other stone fossil specimens of dragonflies date back as much as 300 million years, including some that were huge, with wingspans up to three feet.
Amber is a semi-precious stone that originates as the sap from certain trees. Later fossilized through millions of years of pressure, it's unique for the ability to capture and preserve in near-lifelike form small plant, animal or insect specimens that provide data on ancient ecosystems.
"Dragonflies are now, and probably were then, very quick, evasive, and greedy predators," Poinar said. "They feed on other larvae and insects, mosquitoes, gnats, lots of things. Some are quite beautiful, very popular with insect collectors. And some modern populations like to migrate regionally, going south to mate."
But as the new amber specimen shows, dragonflies are now and for a long time have also been prey, particularly of small lizards. Young and hatchling dinosaurs also probably dined on them, Poinar said.
The quick and merciless battle preserved in this stone took place in the Early Cretaceous somewhere between 97 million to 110 million years ago in the jungles of the Hukawng Valley of Burma, now known as Myanmar. The dragonfly -- with one notably missing part -- is preserved almost perfectly. Only the foot and tail of a small lizard remains in the stone, presumably as the animal was trying to flee.
"It's unfortunate we don't have the entire specimen of the lizard, because it probably had the dragonfly's head in its mouth," Poinar said. "Both died when they were trapped in the tree sap in the middle of this duel."
Like a never-ending feud, these battles are still going on today. Scientists have documented in some sites near waterfalls in Costa Rica that there are many dragonflies of a certain species. But if lizards are present, there are no dragonflies -- it appears they all get eaten.
Astronomers Discover Most Massive Neutron Star Yet Known; Discovery Has Broad Implications for Astrophysics, Nuclear Physics
Astronomers using the National Science Foundation's Green Bank Telescope (GBT) have discovered the most massive neutron star yet found, a discovery with strong and wide-ranging impacts across several fields of physics and astrophysics.
"This neutron star is twice as massive as our Sun. This is surprising, and that much mass means that several theoretical models for the internal composition of neutron stars now are ruled out," said Paul Demorest, of the National Radio Astronomy Observatory (NRAO). "This mass measurement also has implications for our understanding of all matter at extremely high densities and many details of nuclear physics," he added.
Neutron stars are the superdense "corpses" of massive stars that have exploded as supernovae. With all their mass packed into a sphere the size of a small city, their protons and electrons are crushed together into neutrons. A neutron star can be several times more dense than an atomic nucleus, and a thimbleful of neutron-star material would weigh more than 500 million tons. This tremendous density makes neutron stars an ideal natural "laboratory" for studying the most dense and exotic states of matter known to physics.
The scientists used an effect of Albert Einstein's theory of General Relativity to measure the mass of the neutron star and its orbiting companion, a white dwarf star. The neutron star is a pulsar, emitting lighthouse-like beams of radio waves that sweep through space as it rotates. This pulsar, called PSR J1614-2230, spins 317 times per second, and the companion completes an orbit in just under nine days. The pair, some 3,000 light-years distant, are in an orbit seen almost exactly edge-on from Earth. That orientation was the key to making the mass measurement.
As the orbit carries the white dwarf directly in front of the pulsar, the radio waves from the pulsar that reach Earth must travel very close to the white dwarf. This close passage causes them to be delayed in their arrival by the distortion of spacetime produced by the white dwarf's gravitation. This effect, called the Shapiro Delay, allowed the scientists to precisely measure the masses of both stars.
"We got very lucky with this system. The rapidly-rotating pulsar gives us a signal to follow throughout the orbit, and the orbit is almost perfectly edge-on. In addition, the white dwarf is particularly massive for a star of that type. This unique combination made the Shapiro Delay much stronger and thus easier to measure," said Scott Ransom, also of NRAO.
The astronomers used a newly-built digital instrument called the Green Bank Ultimate Pulsar Processing Instrument (GUPPI), attached to the GBT, to follow the binary stars through one complete orbit earlier this year. Using GUPPI improved the astronomers' ability to time signals from the pulsar severalfold.
The researchers expected the neutron star to have roughly one and a half times the mass of the Sun. Instead, their observations revealed it to be twice as massive as the Sun. That much mass, they say, changes their understanding of a neutron star's composition. Some theoretical models postulated that, in addition to neutrons, such stars also would contain certain other exotic subatomic particles called hyperons or condensates of kaons.
"Our results rule out those ideas," Ransom said.
Demorest and Ransom, along with Tim Pennucci of the University of Virginia, Mallory Roberts of Eureka Scientific, and Jason Hessels of the Netherlands Institute for Radio Astronomy and the University of Amsterdam, reported their results in the October 28 issue of the scientific journal Nature.
Their result has further implications, outlined in a companion paper, scheduled for publication in the Astrophysical Journal Letters. "This measurement tells us that if any quarks are present in a neutron star core, they cannot be 'free,' but rather must be strongly interacting with each other as they do in normal atomic nuclei," said Feryal Ozel of the University of Arizona, lead author of the second paper.
There remain several viable hypotheses for the internal composition of neutron stars, but the new results put limits on those, as well as on the maximum possible density of cold matter.
The scientific impact of the new GBT observations also extends to other fields beyond characterizing matter at extreme densities. A leading explanation for the cause of one type of gamma-ray burst -- the "short-duration" bursts -- is that they are caused by colliding neutron stars. The fact that neutron stars can be as massive as PSR J1614-2230 makes this a viable mechanism for these gamma-ray bursts.
Such neutron-star collisions also are expected to produce gravitational waves that are the targets of a number of observatories operating in the United States and Europe. These waves, the scientists say, will carry additional valuable information about the composition of neutron stars.
"Pulsars in general give us a great opportunity to study exotic physics, and this system is a fantastic laboratory sitting out there, giving us valuable information with wide-ranging implications," Ransom explained. "It is amazing to me that one simple number -- the mass of this neutron star -- can tell us so much about so many different aspects of physics and astronomy," he added.
The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.
Scientists from around the world have tried to understand how the Egyptians erected their giant pyramids. Now, an architect and researcher at the Norwegian University of Science and Technology (NTNU) says he has the answer to this ancient, unsolved puzzle.
Researchers have been so preoccupied by the weight of the stones that they tend to overlook two major problems: How did the Egyptians know exactly where to put the enormously heavy building blocks? And how was the master architect able to communicate detailed, highly precise plans to a workforce of 10,000 illiterate men?
A 7-million-ton structure
These were among the questions that confronted Ole J. Bryn, an architect and associate professor in NTNU's Faculty of Architecture and Fine Art when he began examining Khufu's Great Pyramid in Giza. Khufu's pyramid, better known as the Pyramid of Cheops, consists of 2.3 million limestone blocks weighing roughly 7 million tons. At 146.6 meters high, it held the record as the tallest structure ever built for nearly 4000 years.
What Bryn discovered was quite simple. He believes that the Egyptians invented the modern building grid, by separating the structure's measuring system from the physical building itself, thus introducing tolerance, as it is called in today's engineering and architectural professions.
The apex point a key
Bryn has studied the plans from the thirty oldest Egyptian pyramids, and discovered a precision system that made it possible for the Egyptians to reach the pyramid's last and highest point, the apex point, with an impressive degree of accuracy. By exploring and making a plan of the pyramid it is possible to prepare modern project documentation of not just one, but all pyramids from any given period.
As long as the architect knows the main dimensions of a pyramid, he can project the building as he would have done it with a modern building, but with building methods and measurements known from the ancient Egypt, Bryn says.
In a scientific article published May 2010 in the Nordic Journal of Architectural Research, Bryn discusses aspects that can explain the construction of a multitude of the Egyptian pyramids by taking the building grid, and not the physical building itself, as the starting point for the analysis.
A new map
If the principles behind Bryn's drawings are correct, then archaeologists will have a new "map" that demonstrates that the pyramids are not a "bunch of heavy rocks with unknown structures" but, rather, incredibly precise structures.
Ole J. Bryn's findings will be presented and explained at the exhibition The Apex Point in Trondheim from September 13th to October 1st. The exhibition is an official part of the program to celebrate the centenary (1910-2010) of the Norwegian University of Science and Technology.
The development of Bryn's theories on the building grids used in Egyptian pyramids has benefited from cooperation with Dr. Michel Barsoum, Grosvenor and Distinguished Professor at the Department of Materials Science and Engineering, Drexel University, Philadelphia.
lunes, 25 de octubre de 2010
ndonesia ordered thousands of people to evacuate from around Mount Merapi on Monday as it raised the alert for its most active volcano to red, warning of a possible imminent eruption.
Seismic activity has escalated dramatically at the volcano on the densely populated island of Java, with increasing lava spurts and about 500 multi-phased volcanic earthquakes recorded over the weekend, officials said.
The state office of volcanology had upgraded its alert level to red at 6:00 am (2300 GMT), signaling an eruption could be imminent.
"The magma has been pushed upwards due to the escalating seismic energy and it's about a kilometer below the crater," government volcanologist Surono said.
About 19,000 residents have been ordered to evacuate a danger zone of 10 kilometers (six miles) from the crater of the 2,914-meter (9,616-foot) mountain.
About 3,000 have already moved to makeshift camps, officials said.
"The evacuation has been under way since this morning. We put a priority on children, women and elderly," field coordinator Widi Sutikno of the main Sleman district on the southern slopes of the mountain told AFP.
Merapi -- whose name means "Mountain of Fire" -- has been blanketed with clouds since the morning.
Local resident Yanto, 38, said he would remain in his village to tend his sheep.
"I haven't seen any visible threats from Merapi. It is better for young men like me to stay here to look after our livestock. If the volcano does erupt, we can escape quickly," he told AFP.
"Let the children and old people go first to a safer place," he added.
Central Java Governor Bibit Waluyo called for residents to stay calm.
"Procedures are in place to deal with the disaster if it happens so people need not panic," he was quoted as saying by Antara state news agency.
The volcano is the most active of 69 volcanoes with histories of eruptions in Indonesia, which straddles major seismic fault lines in a region known as the "Pacific Ring of Fire."
The archipelago has more active volcanoes than any other country.
Mount Merapi, which lies around 25 kilometers (15.5 miles) north of the town of Yogyakarta in the center of Java, last erupted in June 2006 killing two people.
Its deadliest eruption occurred in 1930 when more than 1,300 people were killed. Heat clouds from another eruption in 1994 killed more than 60 people.
"It currently has more energy than before the 2006 eruption. We haven't found strong indications that it will erupt explosively as it did in 1930 but there is still a possibility," Surono said.
In August, the 2,460-meter (8,100 foot) Mount Sinabung on the island of Sumatra erupted for the first time in 400 years, sending thousands of people into temporary shelters and disrupting flights.
* A decorated gourd dated to 1793 may contain the blood of Louis XVI, who was executed that same year.
* Residue found inside the gourd has been identified as blood, with DNA analysis providing links to the French king.
* Both historical evidence and text fired onto the gourd further connect the blood to Louis XVI.
While storing blood or body parts in a decorated squash might seem unlikely now, it wouldn't have been for the time. Click to enlarge this image.
Carved pumpkins abound this Halloween season, but a decorated gourd dated to 1793 may be the spookiest of them all. New research determines it may contain the blood of Louis XVI, who was executed by guillotine that same year.
The research, accepted for publication in the journal Forensic Science International: Genetics, shows how genetic analysis can provide new historical evidence independent of other traditional sources of information.
The gourd, originally used to store gunpowder, was extensively decorated on the outside with a flame tool. Burned into its surface is the text: "Maximilien Bourdaloue on January 21st, dipped his handkerchief in the blood of Louis XVI after his beheading."
"It is described in contemporaneous accounts that there was a lot of blood in the scaffold after the beheading and that, in fact, many people went there to dip their handkerchiefs in the blood," Carles Lalueza-Fox, lead author of the study and a researcher at Spain's Institute of Evolutionary Biology, told Discovery News.
The handkerchief is now missing from the gourd, but Lalueza-Fox and his team identified a brownish substance on the interior of the dried squash. Biochemical tests determined that the substance was dried blood.
Lalueza-Fox recalled that the king was known for his blue eyes, featured prominently in paintings. He then got the idea of looking for the blue eyes mutation within the dried blood's DNA. The scientists found this mutation, at a gene called HERC2.
The researchers also analyzed other aspects of the blood's genetics, such as its mitochondrial DNA profile, its Y chromosome profile and some other markers. These all revealed that the DNA profile "found inside the gourd is extremely rare in modern Eurasians," suggesting that it may derive from a royal bloodline.
"We have conducted an analysis of the 'person' who is inside the gourd for which we have historical evidence could be the king, but for definite proof we need someone to compare (the findings) with," Lalueza-Fox said.
As luck would have it, a probable organ from such an individual exists. A heart located in a royal French crypt is thought to belong to the king's son, Louis XVII, who died when he was just 10 years old. The heart was cut from the young boy's tumor-ridden body and pickled after Louis XVII spent three horrific years in Paris' Temple Prison.
Bodily remains of Marie Antoinette maternal relatives allowed for genetic comparisons to the DNA in the heart using mitochondrial DNA, which is passed down from a mother to her children. Lalueza-Fox now hopes the gourd blood's DNA can be compared to what's in the heart.
Together, the human remains are reminders of the brutal, 10-year-long French Revolution, which saw the collapse of the country's absolute monarchy. The gourd even has the names of key figures from the revolutionary period burnt into it, including Georges Danton, Jean Paul Marat, Camille Desmoulins, Louis-Sebastien Mercier, Joseph Ignace Guillotin, Maximilien Robespierre, Bernard-Rene de Launay, Jacques de Flesselles and Joseph Foullon.
Another box of text on the dried gourd gives credit to the object's decorator, Jean Roux of Paris.
While storing blood or body parts in a decorated squash might seem unlikely now, Lalueza-Fox said it wouldn't have been for the time.
"It may sound strange today, but probably for a common person witnessing the execution, one of these gunpowder gourds was an acceptable receptacle to preserve something valuable," he explained, suggesting that the gourds were long-lasting, common containers during the 18th century in France.
Eske Willerslev, a Natural History Museum of Denmark evolutionary biologist who is known for his pioneering work on ancient genetics, told Discovery News that "the methodology seems solid" for the new research on the blood.
"It's interesting that such studies of ancient remains of people can actually be used to obtain molecular affiliations of the person and infer some phenotypic traits," Willerslev added.
It's not just poetic to call it a silvery moon: In addition to water, a NASA probe that crashed into a lunar crater last year churned up unexpected concentrations of silver and mercury, aka quicksilver, a new study says.
The metals had been found before in moon rocks brought back by Apollo astronauts, but the elements had appeared in only trace amounts.
The new data, derived from the Lunar Crater Observation and Sensing Satellite (LCROSS) mission, show much higher amounts of silver and mercury in debris from the crash, which happened inside the south-pole crater known as Cabeus.
The surprising find hints at out how water may have arrived on the moon and why it become concentrated at the poles, astronomers say.
When impactors strike the lunar surface, the moon's easily vaporized metals, such as mercury and silver, tend to migrate—atom by atom—toward the cooler poles, much as water vapor in Earth's atmosphere condenses on cold surfaces.
Water and other volatile compounds brought in by asteroids and comets would similarly experience this "cold sink" effect.
"The silver is like a tracer," said study leader Peter Schultz of Brown University in Rhode Island. "It tells us where [moon water] probably came from, and I think it's telling us that it came from comets and asteroids colliding with the moon."
Moon Ice Hiding Climate Clues?
For the LCROSS mission, NASA directed an empty Centaur rocket to smash into a permanently shadowed region of the southern crater. The spacecraft that delivered the rocket recorded the entire event before it was then sent crashing into the moon.
The rocket crash alone gouged a new crater within Cabeus that measures up to 100 feet (30 meters) across.
The impact also sent up to 13,000 pounds (6,000 kilograms) of lunar dust, vapor, and other debris hurtling into space.
In a new paper analyzing this ejecta, LCROSS principal investigator Anthony Colaprete calculates that about 342 pounds (155 kilograms) of water vapor and ice were expelled during the rocket impact.
His team also estimates that at least 5 to 8 percent of the material still inside the Cabeus crater is water ice.
In a separate study, Schultz and his colleagues recorded the silver and mercury abundances, as well as detection of other volatile compounds in the impact plume, including several light hydrocarbons, some sulfur-bearing molecules, and carbon dioxide.
Further studies of these compounds and their concentrations on the moon could provide new information about the history of the solar system, Schultz said.
"We go to Antarctica to study past atmospheres and to look for evidence of past impacts and changes of climate," he said.
"Ice on the moon is probably hiding similar clues, but instead of illuminating Earth's climate, it may tell us about the climate history of the solar system."
Such factors should be considered if humanity comes closer to colonizing the moon and using a lunar base as a way station for deeper jaunts into space, he added.
"We've got to look at the bigger picture. Is [the moon] something we want to save and study before we start exploiting it?"
The new LCROSS findings appear in a suite of three studies published in this week's issue of the journal Science.
Yes, it's yielded human remains—including five females who may have been ritually sacrificed. But it's the signs of life that make a half-excavated Peruvian pyramid of the Moche culture stand out, archaeologists say.
"Often these pyramidal mounds were built as mortuaries more than anything else," said excavation co-leader Edward Swenson.
"In most instances [a pyramid] is not where people live, it is not where they were cooking their food," the University of Toronto archaeologist added.
But the newly exposed 1,400-year-old flat-topped pyramid supported residences for up to a couple dozen elites, who oversaw and perhaps took part in copper production at the site, evidence suggests.
The pre-Inca pyramid dwellers likely presided over important rituals, feasted on roasted llama and guinea pig, and drank corn beer, according to archaeologists working at the site.
Among the signs of occupation are at least 19 adobe stands where large vessels of water and corn beer were stored, as well as scattered llama, dog, guinea pig, and fish bones and traces of coca leaves and red peppers.
"There's a far more robust domestic occupation than what we would have expected," said expedition co-leader John Warner, an archaeologist with the University of Kentucky.
Thriving along Peru's arid northern coast from about A.D. 100 to 800, the Moche culture was composed of independently governed agricultural societies. These groups shared a common religion and a knack for irrigation systems, intricate ceramics, and metallurgy.
In August 2009 Swenson and colleagues began excavating a long mound at the roughly 60-acre (24-hectare) Huaca Colorada site in the Lamayaeque region's southern Jequetepeque Valley. The settlement dates to the Late Moche period, about A.D. 500 to 800.
During the first month of the dig, the team uncovered the mud-brick pyramid within the mound as well as the residences. Later digging turned up evidence of human sacrifice on a rooftop platform: detached body parts and the corpses of five young women, all with signs of ritual burning and one with a rope around her neck.
Measuring about 1,300 feet (390 meters) wide by 460 feet (140 meters) deep, the pyramid is Huaca Colorada's most prominent feature.
Built on a slope, the pyramid appears almost flat when viewed from the north. On its the southern side, however, the monument rises about seven stories at its tallest point—an imposing sight to anyone approaching from that direction.
"They very cleverly utilized the topography to their advantage, to give the appearance of monumentality," Warner said.
"Nasty Business" on Pyramid
Excavations indicate that the Huaca Colorada pyramid may have been home to a group of elite coppersmiths.
On lower levels of the pyramid, for example, are smelting pits, where copper tools and ornaments were fashioned, the archaeologists say. The team also found knives, spatulas, and other copper goods on the pyramid.
It may seem odd that Moche copper workers would have wanted to live above the store, Warner said. For one thing, "copper production is a pretty nasty business from an ecological point of view."
For example, intense fires would have been required to maintain the 1,984-degree-Fahrenheit (1,084-degree-Celsius) temperature necessary for melting copper. The blazes would have cloaked the mound in a dirty, smoky haze, he said.
"It's pretty fascinating that it is occurring in such close proximity to what we right now interpret to be elite residential quarters," Warner said.
Still, the University of Toronto's Swenson said, it's possible the workers lived the high life precisely because of the copper production.
"We know that within a Moche context that metallurgical production is not something that can be understood simply as an economic utility divorced from Moche religious and cultural values," he said.
"It was probably something that was steeped with certain ritual understanding."
Mystery at Huaca Colorada
The unusual nature of Huaca Colorada originally attracted the archaeologists, as the site seems to have been neither an elaborate religious structure nor a political center nor a rustic capital for the surrounding farming community.
"There seem to be some powerful individuals here," but of a unique sort, Swenson said.
Even the murals have a rare flavor. They include well-known figures from Moche iconography such as a serpent and a warrior, but the craftsmanship is informal, almost graffiti-like, compared with murals at other Moche sites.
"Were they allowed a certain amount of prestige and control over their own status—and maybe the labor of others—because of their role in the metallurgical arts?" Swenson said. "It's a possibility."
Secrets of the Fall of the Moche?
The pyramid excavation is in its infancy, according to Swenson, and that raises hopes that the monument may yet reveal more about the poorly understood Moche.
Moche expert Luis Jaime Castillo Butters, for one, is looking for clues as to how the famously independent Moche settlements interacted. The Catholic University of Peru archaeologist is the director of a decades-long excavation at San Jose de Moro, a Moche ceremonial center in the Jequetepeque Valley famed for the discovery of several highly decorated priestesses. Castillo hopes that comparisons of the Colorada finds with those from San Jose de Moro will help clarify whether, as he suspects, the Moche of the valley regularly gathered at San Jose for ritual celebrations.
"The way to approach this quite peculiar aspect of Moche society—religious centralization rather than economic or political—is by looking at San Jose de Moro and the complex sites around it," Castillo said via email.
What's more, Huaca Colorada, being on a rather elevated site on the edge of the Andes, "will be critical to understand the demise of the Moche in the Jequetepeque Valley, because most of the land around the site was wiped away by a huge flood somewhere around the end of the Moche," said Castillo, who isn't involved in the pyramid project.
The Huaca Colorada excavations, he added, should provide "quite a lot of information on the way of life of the Moche in their terminal years."
Household robots could become a reality sooner than we think. But the first hurdle they would have to clear is to prove they can make great pancakes. After all, the breakfast is the most important meal of the day.
A demo posted by Willow Garage, a Palo Alto, California, robotic company, shows two robots working together to make pancakes from a mix. The robots — James and Rosie — even flipped the pancakes correctly.
As you can see in the video (the fun stuff begins at the 1:26 mark) the James robot opened and closed cupboards and drawers, removed the pancake mix from the refrigerator, and handed it to Rosie.
Rosie the robot cooks and flips the pancakes and gives them back to James. Watch for that moment of suspense when Rosie is about to flip the pancake (at the 8:35 mark) and the spontaneous applause from the onlookers when the robot gets it right.
“Behind this domestic tableau is a demonstration of the capabilities of service bots,” says Willow Garage on its blog. “This includes characteristics such as learning, probabilistic inference and action planning.”
For a robot, learning how to flip a pancake is quite a task. Earlier this year, two researchers at the Italian Institute of Technology taught a robot how to do it. The robot had to hold its hand stiffly to throw the pancake in the air and then flex the hand just enough so it could catch the pancake without having it bounce off the pan. It took that robot about 50 tries to get it right.
The latest experiment brought together two different robots: James, a $400,000 robot from Willow Garage and Rosie, a robot from the Technical University Munich. The two robots are among the most sophisticated and advanced humanoid robots today.
James has two stereo camera pairs in its head. The four 5-megapixel cameras are supplemented with a tilting laser range finder. Each of the robot’s forearms has an Ethernet wide-angle camera, while the grippers at the tip have three-axis accelerometers and pressure-sensor arrays on the fingertips. At the base of the robot is another laser range finder.
The PR2 is powered by two eight-core i7 Xeon system servers on-board, 48 GB of memory and a battery system equivalent to 16 laptop batteries or about two hours of battery life.
Rosie has two laser scanners for mapping and navigation, one laser scanner for 3-D laser scans and four cameras, including two 2-megapixel cameras, one stereo-on-chip camera and a Swiss-Ranger SR4000 time-of-flight camera.
The advanced capabilities of the robots came in handy for the task they were assigned. In the demo, one of the robots used the web to solve a cooking problem it faced. The robot looked up a picture on the web and went online to find the cooking instructions for the pancake mix that came from the fridge.
James and Rosie aren’t yet ready “for haute cuisine” say Willow Garage researchers. Nor are they likely to be in your kitchen anytime soon, unless you are ready to pay a couple hundred thousand dollars for a pancake that may not be half as good as the $5 IHOP stack.
But the experiment gives us a pretty good sense of the possibilities. And the robots are cute, besides.
Quick, name the most popular smartphone operating system in the world: It isn’t Android, iPhone or the BlackBerry OS. Say hello to Symbian, an open source mobile OS that’s nearly a decade old. More than 300 million devices worldwide run Symbian. Some 41 percent of smartphones have Symbian on them.
Despite its popularity, Symbian is broken. The operating system’s user interface lacks the snazziness of its rivals, its touchscreen capabilities feel grafted on. It is slow, and developing apps for Symbian is hard.
With younger, prettier competitors in the market, Symbian seems like an aging actress that should have already stepped out of the spotlight.
Symbian also seems to be losing corporate support. Earlier this week, Lee Williams, CEO of the Symbian Foundation resigned for “personal reasons.” Williams, an enthusiastic champion of Symbian and a vocal critic of Google’s Android OS, often did media rounds touting Symbian.
Williams’ exit came on the heels of handset makers Sony Ericsson and Samsung declaring they will no longer manufacture devices running the operating system. With their departures, the only companies left on board with Symbian are Sharp and ZTE (not exactly handset trendsetters), plus Nokia, the one company that truly relies on the OS and with which its fortunes are intricately connected.
Sure, it’s the dominant OS worldwide, but with the rise of smartphones, Symbian hardly seems positioned for the future.
So can Symbian be fixed? Yes, say developers and analysts.
“It’s too early to abandon Symbian,” Nick Jones, an analyst with Gartner Research wrote on his blog last month. “It’s sick, but it’s far from dead; it’s still out-shipping other mobile OSes by a huge margin.”
Freddie Gjertsen, head of product development for Touchnote, an app that is available across Android, iPhone and Symbian, agrees.
“It’s an OS that has had 12 years of continuous development, many thousand of hours of bug testing and fixing. There’s a stability and robustness there that should count for something,” he says. “If Nokia focuses on it, I don’t see why Symbian can’t be fixed.”
Nokia executives says despite the discontent around Symbian, they aren’t willing to give up on the OS. Symbian could put smartphones within the reach of millions of users who can’t pay more than $100 for an unsubsidized device, they say.
To get there, though, Nokia will have to fix four major things: Symbian’s user interface, developer support, app-development environment and the leadership vacuum for the platform.
“How difficult is to fix Symbian? Not so much,” says Rich Green, CTO of Nokia. “You will see some major changes in the forthcoming release of Symbian.”
One of those changes will be to release a version of the OS more often than Symbian’s current schedule of about every 18 months. “That will improve the usability of the OS and keep up with the trend,” says Green.
As for developers, they have the siren call of a global market that can be difficult to resist.
“We can give developers the whole world,” he says. “When you think about the reach Nokia has with Symbian, that is untouched by any other vendor.”
Getting a better UI
Remember older smartphones such as HTC’s Sidekick? They had resistive touchscreens and confusing menus that were difficult to use. The iPhone raised the bar for both hardware and user experience. It ushered in an interface that was clean, driven by icons rather than text-based menus and easy to navigate.
In 2008, when Google launched Android on the HTC G1, it offered a similar experience. Since then, even Microsoft has reinvented its mobile OS to have a UI with some pizzazz.
Not so with Symbian.
“There’s only one problem with Symbian and that is the user interface,” says Jan Ole Suhr, a Berlin, Germany, app developer who has worked on the Symbian platform since 2003.
“From a technical point of view, it is still the best OS: It consumes very little power, is robust and has been there since 2002 running on millions of phones,” he says. But, yes, the UI is really lacking.”
Suhr says it won’t take much to fix the UI but is puzzled that Nokia hasn’t done it so far.
“A change to the UI is not so hard,” he says. “The UI is just the presentation layer of the OS. An OS is far more complex. With a little effort, they can turn around the Symbian ship in no time.”
Nokia executives defend the company’s efforts. Symbian^3 tries to bring a fresh look to the mobile phone UI and future versions of the UI will be better, says Kai Öistämö.
“Android and iOS could start from a blank sheet of paper,” says Öistämö. “But Symbian has to carry the past so it has unfortunately created a bit of slowness in the UI experience.”
Another way to to help developers create better looking apps for the OS is to adopt Qt, an app and UI framework that can work across platforms, says Nokia. Nokia announced Thursday that it’s putting its energies into Qt as the sole app-development platform.
A better development environment
Thinking of developing an iPhone or an Android app? Download the Software Developers Kit (SDK), register, pop open Xcode (for iPhone) or Eclipse (for Android), and you can get started. But if you want to create an app for Symbian, there are just too many choices, developers say. You can develop in native Symbian (Symbian C++), some Java variants, .Net integrated and Qt.
“Over the years, we have had a variety of app platforms that have been prevalent on Symbian,” admits Green.
Qt, which Nokia hopes to promote now, could help change that.
Green explains that Qt is really a term that applies to two things. One is the Qt platform and library that have been extremely successful in the desktop world and allow developers to create cool apps. The second is QML, or Qt Quick, that UI designers can use to rapidly develop attractive UIs.
Qt will also make it easy to create apps that will work across all past and future Nokia devices, including those that will run MeeGo, the new OS that Nokia is developing along with Intel for high-end smartphones.
That’s a big change, says Green. Nokia has had so many versions of the Symbian and development environments that apps created for one set of devices often don’t work on another. It’s a fragmentation problem — similar to what Android OS has seen.
“With Qt we have overhauled our strategy,” says Green. “It’s a big step for hardware and software coherence.”
Talk like that is enough to get developers like Suhr excited. “This is really important, most of the developer community has been waiting for this,” he says. “If Nokia is going to use Qt, the development of SDK and platform is going to be quicker and easier.”
Making it easier to create Symbian apps
But just how hard is it to develop an app for Symbian compared to the iPhone or Android? Even Symbian fans don’t want to sugar-coat the truth. It’s tough, its messy and it’s hard work.
When Touchnote, a London-based app developer whose app turns consumer photos into postcards, set out to create an app for Symbian it turned out to be a long road.
“For us to build a plug-in that connects the camera to the gallery of photos in the application took about four to five weeks of work,” says Gjertsen, who has worked for nearly five years with the Symbian Foundation and the company. “In Android, it took us five minutes. It was a feature built into the OS and we had to just turn it on.” Touchnote is also available on the iPhone.
Raam Thakrar founder of Touchnote says there’s another problem. Finding young developers enthusiastic about Symbian isn’t easy.
“Kids who are coming out of college or have two to five years experience — not many of them are getting into Symbian,” he says. “It makes it much more difficult to build things in Symbian.”
Find developer love in the United States
Mobile apps were around long before Apple introduced the app store. But it is the iPhone app store that has made apps a big driver for smartphones. Consumers now buy smartphones for the apps they can download — which has forced all major smartphone operating systems such as Android and BlackBerry to introduce their own app stores.
Walk into most tech meets in Silicon Valley and there are likely to be iPhone or Android developers lounging about. But try finding a Symbian developer in the crowd — it’s almost impossible. Much of the support for Symbian comes from international developers. That’s natural, considering a majority of Nokia phones are sold outside the United States.
But at a time when the mobile-app environment is being driven out of the United States, the big question is can Symbian move forward without U.S. developer enthusiasm?
“Symbian is very popular all around the world except U.S.,” says Suhr. “Maybe it won’t hurt them to have not enough support in the U.S. but we don’t know.”
Grab control of Symbian
With Sony Ericsson and Samsung bowing out, Symbian, which was always synonymous with Nokia, is now even more closely tied to Nokia.
But Nokia’s history with Symbian has been checkered. Nokia acquired Symbian in 2008 and spun it off as an independent foundation. The idea was to promote Symbian as not just a Nokia platform but an open source system that other handset makers could use. Nokia and Symbian fans hoped this would make the OS more popular. But that hasn’t happened. And now with Samsung and Sony Ericsson dropping support for Symbian, Nokia seems to be the only major handset maker backing the platform.
Developers say Nokia now needs to lead development of Symbian if the OS has to succeed, much like what Google has done with Android.
Nokia needs to scrap the Symbian foundation and bring the OS home, says Gartner’s Jones. The Symbian open source experiment has failed, he declares.
“It which would eliminate time-wasting Foundation activities like release councils, architecture councils, user interface councils,” says Jones on his blog. “What Symbian needs is agility and vision, not committees, and if Symbian is fixable it will be fixed a lot faster under a single leader. Great user interfaces aren’t developed by committees.”
To fix Symbian, Nokia needs to move fast, he says. “Symbian 4 needs to be nothing less than outstanding, if it’s not then Nokia may have to face a difficult decision about whether to abandon Symbian entirely and rebuild Ovi in a new form,” he says.
But former Symbian loyalists such as Gjersten hope it won’t come to that.
“If Nokia took Symbian back in-house, assuming control and leadership, and used Qt to create a good UI, Symbian would be a very different entity from what it is today,” he says.
A new type of sound sensor system has been developed to predict the likelihood of a landslide.
Thought to be the first system of its kind in the world, it works by measuring and analysing the acoustic behaviour of soil to establish when a landslide is imminent so preventative action can be taken.
Noise created by movement under the surface builds to a crescendo as the slope becomes unstable and so gauging the increased rate of generated sound enables accurate prediction of a catastrophic soil collapse.
The technique has been developed by researchers at Loughborough University, in collaboration with the British Geological Survey, through two projects funded by the Engineering and Physical Sciences Research Council (EPSRC).
The detection system consists of a network of sensors buried across the hillside or embankment that presents a risk of collapse. The sensors, acting as microphones in the subsoil, record the acoustic activity of the soil across the slope and each transmits a signal to a central computer for analysis.
Noise rates, created by inter-particle friction, are proportional to rates of soil movement and so increased acoustic emissions mean a slope is closer to failure. Once a certain noise rate is recorded, the system can send a warning, via a text message, to the authorities responsible for safety in the area. An early warning allows them to evacuate an area, close transport routes that cross the slope or carry out works to stabilise the soil.
Neil Dixon, professor of geotechnical engineering at Loughborough University and principal investigator on the project, explains how the system -- thought to be a global first -- works. "In just the same way as bending a stick creates cracking noises that build up until it snaps, so the movement of soil before a landslide creates increasing rates of noise," said Professor Dixon.
"This has been known since the 1960s, but what we have been able to do that is new is capture and process this information so as to quantify the link between noise and soil displacement rates as it happens, in real time -- and hence provide an early warning," he added.
The system is now being developed further to produce low cost, self-contained sensors that do not require a central computer. This work, which is being carried out under the second project funded by EPSRC, is focused on manufacture of very low cost sensors with integrated visual and/or audible alarms, for use in developing countries. Ongoing work includes field trials, market research and planning commercial exploitation of the technology.
"The development of low cost independent acoustic slope sensors has only become possible in very recent times due to the availability of microprocessors that are fast, small and cheap enough for this task," says Dixon.
As well as the life-saving implications for countries prone to disastrous landslides, the technique can also be used in monitoring the condition of potentially unstable slopes built to support transport infrastructure, such as rail and road embankments, in developed countries such as the UK.
Current development work is being funded through Loughborough University's knowledge transfer account, a fund supplied by EPSRC to help commercial exploitation of inventions arising from its research projects. A commercially available Alarms sensor is expected to be launched in the next two years.
The Terminator. The Borg. The Six Million Dollar Man. Science fiction is ripe with biological beings armed with artificial capabilities. In reality, however, the clunky connections between living and non-living worlds often lack a clear channel for communication. Now, scientists with the Lawrence Berkeley National Laboratory (Berkeley Lab) have designed an electrical link to living cells engineered to shuttle electrons across a cell's membrane to an external acceptor along a well-defined path. This direct channel could yield cells that can read and respond to electronic signals, electronics capable of self-replication and repair, or efficiently transfer sunlight into electricity.
"Melding the living and non-living worlds is a canonical image in science fiction," said Caroline Ajo-Franklin, a staff scientist in the Biological Nanostructures Facility at the Molecular Foundry. "However, in most attempts to interface living and non-living systems, you poke cells with a sharp hard object, and the cells respond in a predictable way -- they die. Yet, in Nature many organisms have evolved to interact with the rocks and minerals that are part of their environment. Here, we took inspiration from Nature's approach and actually grew the connections out of the cell."
Coaxing electrons across a cellular membrane is not trivial: attempts to pull an electron from a cell may disrupt its function, or kill the entire cell in the process. What's more, current techniques to transfer cellular electrons to an external source lack a molecular roadmap, which means even if electrons do turn up outside a cell, there is no way to direct their behavior, see where they stopped along the way, or send a signal back to the cell's interior.
"We were interested in finding a pathway that wouldn't kill the living systems we were studying," said Heather Jensen, a graduate student at University of California, Berkeley whose thesis work is part of this publication. "By using a living system in electronics, we can one day create biotechnologies that can repair and self-replicate."
In their approach, Jensen, Ajo-Franklin and colleagues first cloned a part of the extracellular electron transfer chain of Shewanella oneidensis MR-1, marine and soil bacteria capable of reducing heavy metals in oxygen-free environments. This chain or "genetic cassette," Ajo-Franklin notes, is essentially a stretch of DNA that contains the instructions for making the electron conduit. Additionally, because all life as we know it uses DNA, the genetic cassette can be plugged into any organism. The team showed this natural electron pathway could be popped into a (harmless) strain of E. coli -- a versatile model bacteria in biotechnology -- to precisely channel electrons inside a living cell to an inorganic mineral: iron oxide, also known as rust.
Bacteria in environments without oxygen, such as Shewanella, use iron oxide from their surroundings to breathe. As a result, these bacteria have evolved mechanisms for direct charge transfer to inorganic minerals found deep in the sea or soil. The Berkeley Labs team showed their engineered E. coli could efficiently reduce iron and iron oxide nanoparticles -- the latter five times faster than E. coli alone.
"This recent breakthrough is part of a larger Department of Energy project on domesticating life at the cellular and molecular level. By directly interfacing synthetic devices with living organisms, we can harness the vast capabilities of life in photo- and chemical energy conversion, chemical synthesis, and self-assembly and repair," said Jay Groves, a faculty scientist at Berkeley Labs and professor of chemistry at University of California, Berkeley. "Cells have sophisticated ways of transferring electrons and electrical energy. However, just sticking an electrode into a cell is about as ineffective as sticking your finger into an electrical outlet when you are hungry. Instead, our strategy is based on tapping directly into the molecular electron transport chain used by cells to efficiently capture energy."
The researchers plan to implement this genetic cassette in photosynthetic bacteria, as cellular electrons from these bacteria can be produced from sunlight -- providing cheap, self-replicating solar batteries. These metal-reducing bacteria could also assist in producing pharmaceutical drugs, Ajo-Franklin adds, as the fermentation step in drug manufacturing requires energy-intensive pumping of oxygen. In contrast, these engineered bacteria breathe using rust, rather than oxygen, saving energy.
A paper reporting this research titled, "Engineering of a synthetic electron conduit in living cells," appears in Proceedings of the National Academy of Sciences. Co-authoring the paper with Jensen, Ajo-Franklin and Groves were Aaron Albers, Konstantin Malley, Yuri Londer, Bruce Cohen, Brett Helms and Peter Weigele.
Portions of this work at the Molecular Foundry were supported by DOE's Office of Science.
Some bacteria react to the cold by subtly changing the chemistry of their outer wall so that it remains pliable as temperatures drop. Scientists identified a key protein in this response mechanism a few years ago, but the question of how bacteria sense cold in the first place remained a mystery. Based on a study by scientists at Rice University and Argentina's National University of Rosario, the answer is: They use a measuring stick.
The study, published in the September issue of Current Biology, involved a series of intricate experiments on the bacteria Bacillus subtilis. The researchers found a specialized protein that protrudes through the bacteria's outer cell wall acts as a measuring stick that's tuned to give a signal when temperatures outside the cell drop.
Scientists have long known that cells use specialized proteins called "transmembrane" proteins to sense and react to the outside world. Transmembrane proteins protrude through the cell's outer wall, or membrane.
"All living cells have the ability to respond to external stimuli, but in most cases that we are aware of, signal recognition -- the event that triggers the response -- occurs when a transmembrane protein binds physically to another chemical outside the cell," said study co-author Ariel Fernandez, research professor at Rice.
Fernandez said the Bacillus subtilis study is one of the first to determine how a transmembrane protein can respond indirectly to a physical stimulus outside the cell. The research was highlighted in review articles in both Current Biology and Nature Reviews Microbiology.
He and colleagues examined a transmembrane protein called DesK (pronounced des-KAY). In previous studies, scientists had found that DesK responded to cold temperatures by causing the cell to make a special compound that keeps the membrane pliable. Without the compound, the fatty acids inside the cell wall become more rigid as temperatures fall.
Fernandez and colleagues found that the part of the DesK protein that protrudes outside the cell contains a sensitized tip. As long as the tip remains in contact with water molecules outside the cell, DesK remains switched off. As temperatures fall and the cell membrane becomes more rigid, the membrane also becomes thicker. As it thickens, it engulfs the sensitized end of the temperature probe, cutting off contact with water molecules outside the cell. This, in turn, activates DesK and sends the signal to release the cold-protecting chemicals. This mechanism, which Fernandez named the buried buoy trigger, was proposed by Fernandez and probed experimentally by the Argentinean team.
The molecular biology and experimental probes were conducted in the laboratory of Diego de Mendoza at the National University of Rosario in Rosario, Argentina. To confirm the findings, the group constructed versions of DesK proteins of varying lengths. Using these as longer or shorter measuring sticks, the researchers confirmed that the signaling mechanism was triggered based upon whether the tip of the transmembrane sensor remained in contact with water molecules outside the membrane.
Co-authors of the research include Larisa Cybulski, Mariana Martin and Maria Mansilla, all of the National University of Rosario. The research was supported by the National Institutes of Health, Argentina's National Scientific and Technical Research Council, Argentina's National Agency for Science and Technology Promotion and the Howard Hughes Medical Institute.
he pre-Columbian Indian societies that once lived in the Amazon rainforests may have been much larger and more advanced than researchers previously realized. Together with Brazilian colleagues, archaeologists from the University of Gothenburg have found the remains of approximately 90 settlements in an area South of the city of Santarém, in the Brazilian part of the Amazon.
"The most surprising thing is that many of these settlements are a long way from rivers, and are located in rainforest areas that extremely sparsely populated today," says Per Stenborg from the Department of Historical Studies, who led the Swedish part of the archaeological investigations in the area over the summer.
Traditionally archaeologists have thought that these inland areas were sparsely populated also before the arrival of the Europeans in the 16th and 17th centuries. One reason for this assumption is that the soils found in the inland generally is quite infertile; another reason is that access to water is poor during dry periods as these areas are situated at long distances from the major watercourses. It has therefore been something of a mystery that the earliest historical account; from Spaniard Francisco de Orellana's journey along the River Amazon in 1541-42, depicted the Amazon as a densely populated region with what the Spanish described as "towns," situated not only along the river itself, but also in the inland.
New Discoveries Could Change Previous Ideas
The current archaeological project in the Santarém area could well change our ideas about the pre-Columbian Amazon. The archaeologists have come across areas of very fertile soil scattered around the otherwise infertile land. These soils, known as "Terra Preta do Indio," or "Amazonian Dark Earth," are not natural, but have been created by humans (that is, they are "anthrosols").
"Just as importantly, we found round depressions in the landscape, some as big as a hundred metres in diameter, by several of the larger settlements," says Stenborg. "These could be the remains of water reservoirs, built to secure water supply during dry periods."
It is therefore possible that the information from de Orellana's journey will be backed up by new archaeological findings, and that the Amerindian populations in this part of the Amazon had developed techniques to overcome the environmental limitations of the Amazonian inlands.
Archaeological Rescue Efforts Are Urgent
The archaeological sites in the Santarém area are rich in artefacts, particularly ceramics. A large and generally unstudied collection of material from the area is held by the Museum of World Culture in Gothenburg. Collected in the 1920s by the Germano-Brazilian researcher Curt Unkel Nimuendajú, the material ended up in the Museum of Ethnography in Gothenburg and is essential for increasing our knowledge of the pre-Columbian Amazon. Brazilian researchers are therefore interested in joint projects, where new field studies are combined with research into the contents of the Museum of World Culture's collections from the same area.
"The Santarém area is presently experiencing intensive exploitation of various forms, including expansion of mechanized agriculture and road construction," says Dr. Denise Schaan at Universidade Federal do Pará. "This means that the area's ancient remains are being rapidly destroyed and archaeological rescue efforts are therefore extremely urgent."
"Our work here is a race against time in order to obtain archaeological field data enabling us to save information about the pre-Columbian societies that once existed in this area, before the archaeological record has been irretrievably lost as a result of the present development," states Brazilian archaeologist Márcio Amaral-Lima at Fundação de Amparo e Desenvolvimento da Pesquisa, in Santarém.
The archaeological investigation forms part of a wider project led by the University of Gothenburg's Per Stenborg, PhD. The project is being carried out in collaboration with Brazilian archaeologists Denise Schaan (Universidade Federal do Pará) and Marcio Amaral-Lima (Fundação de Amparo e Desenvolvimento da Pesquisa, Laboratório de Arqueologia Curt Nimuendaju, Santarém), and is funded by grants from the Stiftelsen för Humanistisk Forskning, the Royal Swedish Society of Sciences and Letters in Gothenburg, Rådman och Fru Ernst Collianders Stiftelse, Stiftelsen Otto och Charlotte Mannheimers fond, and the universities in Pará and Gothenburg.
miércoles, 20 de octubre de 2010
Rarely do you read an article where pulsars are considered "run of the mill." Let's face it, they are pretty extreme. However, new observations of an even more extreme astrophysical object suggest that it may have been masquerading as a "normal" pulsar all along.
Pulsars are a subset of neutron stars, the dense remnants of stellar cores left behind after supernovae. A pulsar doesn't actually pulse, but it does spin rapidly. Hotspots on the surface, thought to be at the magnetic poles, are often detected with radio telescopes as they rotate into our line of sight. So really, pulsars are a bit like lighthouses.
Magnetars are pulsars with much stronger magnetic fields. As a result, they exhibit all kinds of weird characteristics, such as pulsing in the x-ray and giving off sporadic bursts of high energy emission. Sixteen such magnetars are known.
It is interesting to note how you even measure the magnetic field of such a distant and weird object. There is a well-known relation in pulsar physics that allows you to determine the dipole magnetic field strength (illustrated in the artist's conception above, outside the star) just from the period of the pulsar spin and the spin-down rate. The spin-down rate is the measure of how the pulsar rotation slows down as it ages and loses energy.
Enter SGR 0418+5729, detected in June 2009 when it went through several bursts indicative of magnetar behavior. This new x-ray pulsar and "soft-gamma repeater" had a period of 9.1 seconds, also typical for a magnetar. Follow-up observations continued for five months as astronomers waited for signs of pulsar spin-down. However, it never seemed to slow, to the detection limit of their instruments, before it got too close to the sun to be observed.
Starting in July of this year, astronomers marshalled the forces of several x-ray telescopes to monitor this strange pulsar again. In an article on Science Express, they report a new upper limit on the spin-down rate, which means they still have not reliably detected a slowing of the rotation. When you take this through the magnetic field calculations, you find that the dipole magnetic field has to be much lower than that of a magnetar, and that it instead lies in the range of normal pulsars.
A plot for the real pulsar nerds. The x-axis is the spin period of the pulsar, and the y-axis is the spin-down rate. Normal pulsars are black dots and magnetars are red stars. SGR 0418+5729 is plotted with the upper limit for its spin-down and magentic field strength.
Astronomers are currently unable to determine what is powering the x-ray outbursts of SGR 0418+5729, thought it may be a much stronger interior magnetic field that has not been detected (see top illustration again). This find may also mean that other "run of the mill" pulsars are tantrum-throwing magnetars just waiting to happen! However, as the paper's first author, Nanda Rea, notes, more study will be needed to see if this not-so-magnetized magnetar is the exception or the rule.
Credit: NASA/CXC/M.Weiss. Bottom: Credit: N. Rea.
One Colorado soda company has developed a line of sodas that have an usual ingredient: marijuana. Dixie Elixirs has made their drinks available to anyone with a prescription for medical marijuana.
The drinks come in eight different flavors, including pink lemonade, root beer and grape. But if the company really wants to get their drinks into the hands of marijuana lovers, they may want to start working on pizza and nachos flavors.
But marijuana is only legal to consume in 14 states with a prescription from a doctor. So, unless you are one of the approximately half-million people who is a medical marijuana patient, this pot-infused soda won't do you much good.
It's an open secret that you can smoke marijuana and still be a valuable part of society. But when you think of smoking weed, you're more likely to think of Cheech and Chong than the people running the United States government. (Even though at least two U.S. presidents have admitted smoking it.)
The drink makers say part of the reason they developed their line of mary-jane drinks was to remove that "reefer madness" stigma associated with marijuana smokers.
If California voters decide to make recreational marijuana legal this November, you may start seeing these organic sodas (the drink makers really know their audience) in grocery stores and liquor stores right next to the stuff from Pepsi and Coke.
But if Coca-Cola's history is any sign of what the company might do next, they could return to the heady days of putting mind-altering substances in their sodas.
At a time of sagging soda sales, drink makers are looking for a way to boost sales, and marijuana might be the answer. Medical marijuana has already proven an effective way at boosting newspaper sales, of all things. The New York Times reports that medical marijuana ads in small Colorado newspapers boost revenues enough for it to increase the size of its staff.
* NASA has awarded contracts worth $30 million total to six teams for technical information about their privately funded lunar probes.
* The firms are all contenders or partners in the $30 million Google Lunar X Prize competition.
* The program may pave the way for NASA to buy science data about the moon on a commercial basis.
Congress may have put the kibosh on NASA's plan to return astronauts to the moon, but that doesn't mean the agency is giving up its lunar ambitious. The new plan? Pay others to go.
There's a rich pool of partners to choose from, thanks to a Google-sponsored competition offering $30 million in prizes for landing and operating rovers on the moon. So far, the contest, which is based on the 2004 $10 million Ansari X Prize competition for privately funded human spaceflights, has drawn 22 contenders.
Last week NASA picked six Google Lunar X Prize teams to work with, hoping to glean technological shortcuts for building, flying and operating robotic probes.
"We hope this will inform NASA's internal efforts to develop landers, not only for the moon, but also for asteroids and other missions," Nantel Suzuki, a manager in the agency's Exploration division, told Discovery News.
It's a low-risk venture for the government, which only pays if and when the contractors deliver. Initially, NASA will buy information about the companies' spacecraft designs and their testing processes.
As the firms launch, fly, land and operate their probes, the scope of NASA's interest -- and the amount of money it's willing to pay -- expands.
In this first round of lunar commercial initiatives, NASA is offering between $10,000 and $10 million for technical information, such as precision landing systems. But in follow-on programs, the agency will likely buy science data on a commercially available basis as well.
"We're not funding the missions themselves," said Suzuki. "These teams had to, as part of the proposal, not only explain their technical capabilities, but also their business potential. They had to demonstrate they had viable end-to-end lunar missions … and some kind of business strategy. It's the combination of those things that make this unique, I think."
"We did discover that there are some very exciting missions being planned and some impressive capabilities. There are cost challenges and there's the hope that the government can leverage investments that are being brought to bear from private sources, and that's indeed what we found."
The goal of the Google Lunar X Prize is to land a rover on the moon, move it at least 500 meters (1,650 feet) and transmit images back to Earth. The first team to succeed before Dec. 31, 2012, wins a $20 million grand prize. Finishing second is worth $10 million. Bonus money is available for special tasks, such as locating a relic from the Apollo or Soviet moon programs, or finding water ice in a lunar crater.
NASA's partners in the commercial lunar initiative, called the Innovative Lunar Demonstrations Data, are:
-Astrobotic Technology Inc., of Pittsburgh
-The Charles Stark Draper Laboratory Inc., of Cambridge, Mass.
-Dynetics Inc., of Huntsville, Ala.
-Earthrise Space Inc.., of Orlando
-Moon Express Inc., of San Francisco
-Team FREDNET, The Open Space Society Inc., of Huntsville
"As someone who worked on the original Apollo propulsion for the lunar lander, I look forward to returning to the moon," said Astrobotic team member Carl Stechman, a lead propulsion engineer with Aerojet.
"If these companies are able to sustain themselves, they may eventually be in the position to provide cargo delivery services or to sell science data to us," added Suzuki.