Tag: lead author (page 3 of 4)

4.4 Billion Year Old Meteorite From Elusive Martian Crust

Excerpt from designntrend.comResearch on a 4.4 billion-year-old meteorite reveals that it is a piece of the Red Planet's crust - the first piece of its kind to reach Earth. The study, which was carried out by researchers at Brown University sug...

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Study Suggests Baby Chicks Can Count! ~ Video





Excerpt from nbcnews.com
By Tia Ghose, LiveScience



It's not just humans who can count: Newly published research suggests chicks seem to have a number sense, too. 

Scientists found that chicks seem to count upward, moving from left to right. They put smaller numbers on the left, and larger numbers on the right — the same mental representation of the number line that humans use. 

"Our results suggest a rethinking of the relationship between numerical abilities and verbal language, providing further evidence that language and culture are not necessary for the development of a mathematical cognition," said study lead author Rosa Rugani, a psychologist at the University of Padova in Italy.

The left-to-right way of thinking about ascending numbers seems to be embedded in people's mental representations of numbers, but it's not clear exactly why. Is it an artifact of some long-lost accident of history, or is it a fundamental aspect of the way the brain processes numbers? 

To help answer those questions, Rugani and her colleagues trained 3-day-old chicks to travel around a screen panel with five dots on it to get to a food treat behind it. This made the five-dot panel an anchor number that the chicks could use for comparison with other numbers. 

After the chicks learned that the five-dot panel meant food, the researchers removed that panel and then placed the chicks in front of two panels, one to the left and the other to the right, that each had two dots. The chicks tended to go to the left panel, suggesting that they mentally represent numbers smaller than five as being to the left of five. 

When the researchers put the chicks in front of two panels that each had eight dots, the chicks walked to the panel on the right. This suggests the chicks mentally represent numbers larger than five as being to the right of five, the researchers said. 

In a second experiment, the researchers repeated the whole process, but started with a panel that had 20 dots instead of five. They then added two other panels that had either eight or 32 dots. Sure enough, the baby chicks tended to go to the left when the screens had just eight dots, and to the right when they had 32 dots, according to the findings published in this week's issue of the journal Science. 

"I would not at all be surprised that the number spatial mapping is also found in other animals, and in newborn infants," Rugani said.



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New prehistoric human discovered in Taiwan



human jaw fossil found in Taiwan
“Penghu 1,” the newly discovered human with large teeth, is another piece of critical evidence suggesting that other humans besides Homo sapiens lived in Asia from 200,000 to 10,000 years ago.


Excerpt from sciencerecorder.com


Paleontologists have identified the first known prehistoric human specimen from Taiwan, which may have been part of a species that lived alongside modern humans until as recently as 10,000 years ago.
“Penghu 1,” the newly discovered human with large teeth, is another piece of critical evidence suggesting that other humans besides Homo sapiens lived in Asia from 200,000 to 10,000 years ago.
Among the species that lived in Europe within that period were Neanderthals, Denisovans and Homo floresiensis The Penghu 1, which has been described in the most recent issue of Nature Communications, has added to that sizable list of humans that may have lived with and interbred with modern humans.

“The available evidence at least does not exclude the possibility that they survived until the appearance of Homo sapiens in the region, and it is tempting to speculate about their possible contact,” said the study’s co-author Yousuke Kaifu, an associate professor in the Department of Biological Sciences at The University of Tokyo, to Discovery News.
Kaifu, along with the paper’s lead author Chun-Hsiang Chang, and their team have studied the new human’s remains, primarily a jawbone that still contains big teeth. The jawbone was found by fishermen off the Taiwanese coast in the Penghu Channel. They then sold it to a local antique shop where it was found and bought by the collector Kun-Yu Tsai, who donated his collection to the National Museum of Natural Science in Taiwan. It then caught the eye of Chang, who works at the museum as a geologist.
Chang and his team now believe that the Penghu 1 could suggest a new species of human or at least a distinct regional group of Homo erectus. He suspects that the jawbone belonged to an elderly adult due to the worn state of the teeth. Unlike Homo floresiensis, the Penghu 1 grew to adult stature and lived on the Asian mainland.
“The associated faunal remains suggest that the area was a relatively open, wet woodland,” said Kaifu. “This is because of the presence of large-bodied mammals, such as elephants (Stegodon), horses and bear, but the fauna also included animals that prefer marshlands in a hot and humid climate, such as water buffaloes.”
All of these aspects would seem very attractive to modern humans, as well as the prehistoric humans they co-existed with. Although Penghu 1 is clearly not a modern human, its jaw bears many similarities to Homo erectus. Very little is known about human evolution in Asia, so this is a considerably welcome discovery, as fossils from much earlier periods discovered in China have offered valuable insights into what a Cretaceous ecosystem looked like. There are also many similarities between Penghu 1 and the Peking Man remains from Zhoukoudian, China, although the former appears to be much more primitive. It has also been compared to the archaic Homo heidelbergensis and also Denisovan remains.

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Scientists Slow Down The Speed Of Light in Lab


Photon race rendering
Two photons, or particles of light approach a finish line used to determine if light can travel at different speeds through the air. Illustration courtesy University of Glasgow

Excerpt from popsci.com


Light passes through air at about 299,000,000 meters per second, an accepted constant that hasn’t been challenged—until now. By manipulating a single particle of light as it passed through free space, researchers have found a way to slow down the speed of light through air.

Scientists have known for a while how fast light passes through different mediums, such as water or glass, and how to slow that speed down. But researchers at the University of Glasgow and Heriot-Watt University decided to take this concept further and see if the speed of light could be changed as it passes through gases.
To make that happen, the team decided to look at individual light particles, or photons. “Measuring with single photons is the cleanest experiment you can get,” Jacquiline Romero, one of the study’s lead authors and a physics professor at the University of Glasgow, tells Popular Science. The group wanted to explicitly establish that different photons have different velocities depending on their placement within a light beam's structure. Depending on where a photon is in a light beam, it has either a slower or faster relative speed. It's similar to a group of runners: Even as the group stays together, the one at the front has to constantly be moving faster than the ones at the side or in the back. Daniel Giovannini, another study lead author from the University of Glasgow, says that researchers have known this for a while, but the team wanted to know just how slow the photons in the 'back of the pack' are moving.

The experiment set out to measure the arrival times of single photons, Romero says. To do that, the researchers passed one photon through a filter, which changed the photon's structure. They then compared the velocity of this photon to an unstructured photon. The researchers were able to decrease the velocity of the structured photon through air by 0.001 percent, which seems quite small, but the amount was not accidental. “We had to try it out and convince ourselves that it can be done and that it’s real,” Giovannini says. He and Romero say they anticipate the results will be divisive, between people who think the conclusion is obvious and those who think it’s a groundbreaking experiment.

The study was published January 23 in Science Express.

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Meteorite is ‘hard drive’ from space ~ Researchers decode ancient recordings from asteroid ~ BBC


Pallasite meteorite
The Esquel meteorite consists of gem-quality crystals embedded in metal.



Excert from bbc.com

Researchers have decoded ancient recordings from fragments of an asteroid dating back billions of years to the start of the Solar System. 

They found tiny "space magnets" in meteorites which retain a memory of the birth and death of the asteroid's core.
Like the data recorded on the surface of a computer hard drive, the magnetic signals written in the space rock reveal how Earth's own metallic core and magnetic field may one day die.

The work appears in Nature journal.

Using a giant X-ray microscope, called a synchrotron, the team was able to read the signals that formed more than four-and-a-half billion years ago, soon after the birth of the Solar System.

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It's like a cosmic archaeological mission”
Dr James Bryson University of Cambridge
The meteorites are pieces of a parent asteroid that originally came from asteroid belt, between Mars and Jupiter.
They represents the left-over fragments of a planet that failed to form. The magnetic recording within it traps a signal of the precise moments when an iron-rich core formed in the asteroid as well as when it froze, killing its magnetic field.
The new picture of metallic core solidification in the asteroid provide clues about the magnetic field and iron-rich core of Earth.
Core values "Ideas about how the Earth's core evolved through [our planet's] history are really changing at the moment," lead researcher Dr Richard Harrison, from the University of Cambridge, told BBC News.
"We believe that Earth's magnetic field is linked to core solidification. Earth's solid inner core may have started to form at very interesting time in terms of the evolution of life on Earth.
"By studying an asteroid we get to see this in fast forward. We can see the start of core solidification in the magnetic records as well as its end, and start to think about how these processes work on Earth."

Magnetic fieldThe Earth's magnetic field will likely die off when the core completely freezes
The meteorites studied by the team originally fell to Earth in Argentina, and are composed of gem-quality crystals enclosed in a metallic matrix of iron and nickel. 

Tiny particles, smaller than one thousandth the width of a human hair, trapped within the metal have retained the magnetic signature of the parent asteroid from its birth in the early Solar System.

"We're taking ancient magnetic field measurements in nano-scale materials to the highest ever resolution in order to piece together the magnetic history of asteroids - it's like a cosmic archaeological mission," said Dr James Bryson, the paper's lead author. 

"Since asteroids are much smaller than Earth, they cooled much more quickly, so these processes occur on a shorter timescales, enabling us to study the whole process of core solidification."

Prof Wyn William, from the University of Edinburgh, who was not involved in the study, commented: "To be able to get a time stamp on these recordings, to get a cooling rate and the time of solidification, is fantastic. It's a very nice piece of work."

The key to the long-lived stability of the recording is the atomic-scale structure of the iron-nickel particles that grew slowly in the asteroid core and survived in the meteorites. 

Making a final comment on the results, Dr Harrison said: "In our meteorites we've been able to capture both the beginning and end of core freezing, which will help us understand how these processes affected the Earth in the past and provide a possible glimpse of what might happen in the future." 

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Nibiru? Solar system may have Planet X & Planet Y

 




Scientists have postulated the existence of possibly two undiscovered planets beyond the orbit of Neptune to explain discrepancies in the orbits of extreme trans-Neptunian objects (ETNO). The objects have orbits that take them beyond the orbit of the planet Neptune.

Theory predicts that they be randomly distributed and that their orbits must have a semi-major axis with a value around 150 AU; an orbital inclination of nearly zero degrees; and an angle of perihelion, the point in the object’s orbit at which it is closest to the Sun, of zero to 180 degrees.

However, a dozen ETNO do not fit these orbital criteria. These objects have semi-major axis values of 150 to 525 AU, orbital inclinations of around 20 degrees, and angles of perihelion far from 180 degrees.

According to a statement, a new study by astrophysicists at the Complutense University of Madrid (UCM) and University of Cambridge have calculated that these orbital discrepancies could be explained by the existence of at least two additional planets beyond the orbits of Neptune and dwarf planet Pluto. Their study suggests that the gravitational pulls of those two planets must be disturbing the orbits of some smaller ETNO.

However, there are two difficulties with the hypothesis. One is that current models of the formation of our solar system do not allow for additional planets beyond Neptune. Secondly, the team’s sample size is very small, only 13 objects. However, additional results are in the pipeline, which will expand the sample.

“This excess of objects with unexpected orbital parameters makes us believe that some invisible forces are altering the distribution of the orbital elements of the ETNO and we consider that the most probable explanation is that other unknown planets exist beyond Neptune and Pluto,” said Carlos de la Fuente Marcos of UCM and lead author on the study.

The new findings have been published in two papers published in the journal Monthly Notices of the Royal Astronomical Society Letters.

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Lost memories may not be gone forever, new brain research says




Excerpt from
sciencerecorder.com


New research from the University of California at Los Angeles (UCLA), studying how memories are stored, finds that lost memories can be recovered—offering possible hope for patients suffering from the early stages of Alzheimer’s disease.

The finding contradicts the long-held belief that memories are stored at the connections between neurons, or synapses—areas that are destroyed by Alzheimer’s disease.

“Long-term memory is not stored at the synapse,” said lead author David Glanzman, a UCLA professor of integrative biology and physiology and of neurobiology, in a statement. “That’s a radical idea, but that’s where the evidence leads.”

According to Glanzman, the nervous system can regenerate lost or broken synaptic connections. If synaptic connections can be restored, memory will return. “It won’t be easy, but I believe it’s possible,” he said.

The findings recently were published in the open-access journal eLife.

Glanzman said the finding that the destruction of synapses does not result in the destruction of memories could have important implications for people with Alzheimer’s disease.

“As long as the neurons are alive, the memory will still be there, which means you may be able to recover some of the lost memories in the early stages of Alzheimer’s,” Glanzman said.

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NASA’s Kepler finds massive alien planet 180 light years away

Excerpt from theweek.com NASA's Kepler finds massive alien planet 180 light years away NASA's Kepler space telescope has discovered its first alien planet since malfunctioning in May 2013,...

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Is This What Really Killed the Dinosaurs?


Portrait of a killer: volcanoes were no friend to the dinos

Excerpt from time.com 

It wasn't just an asteroid

At the start of the 1980s, the question of what forced dinosaurs and huge numbers of other creatures to become extinct 65 million years ago was still a mystery. By the decade’s end, that mystery was solved: a comet or asteroid had slammed into Earth, throwing so much sun-blocking dust into the air that the planet plunged into a deep-freeze. The discovery of a massive impact crater off the coast of Mexico, of just the right age, pretty much sealed the deal in most scientists’ minds.

But a second global-scale catastrophe was happening at much the same time: a series of ongoing volcanic eruptions that dwarf anything humans have ever seen. They were so unimaginably powerful that they left nearly 200,000 square miles (518,000 sq. km) of what’s now India buried in volcanic basalt up to a mile and a half thick. And the gases and particulate matter spewed out by those eruptions, argue at least some scientists, could have played a big role in the dinosaurs’ doom as well.
How big a role, however, depends on exactly when the eruptions began and how long they lasted, and a new report in Science goes a long way toward answering that question. “We can now say with confidence,” says Blair Schoene, a Princeton geologist and lead author of the paper, “that the eruptions started 250,000 years before the extinction event, and lasted for a total of 750,000 years.” And that, he says, strengthens the idea that the eruptions could have contributed to the mass extinction of multiple species.

Schoene and his co-authors don’t claim volcanoes alone wiped out the dinosaurs; only that they changed the climate enough to put ecosystems under stress, setting them up for the final blow. “We don’t know the exact mechanism,” he admits. Volcanoes emit carbon dioxide, which could have triggered an intense burst of global warming, but they also emit sulfur dioxide, which could have caused global cooling. “What we do know,” Schoene says, “is that earlier mass extinctions were caused by volcanic eruptions alone.” The new dates, he and his co-authors believe, will help scientists understand what role these volcanoes played in the dinosaurs’ demise.

If there was such a role, that is, and despite this new analysis, plenty of paleontologists still doubt it seriously. The dating of the eruptions, based on widely accepted uranium-lead measurement techniques, is not an issue, says Brian Huber, of the Smithsonian Institution. “That part of the science is great,” he says. “It moves things forward.”

And those data, Huber says, make it clear that the extinction rate for the 250,000 years leading up to the asteroid impact wasn’t especially large. Then, at the time of the impact: whammo. The idea that volcanoes played a significant role in this extinction event keeps coming up every so often, and in Huber’s view, “the argument has gotten very tiresome. I no longer feel the need to put any energy into it. It’s from a minority arguing against overwhelming evidence.”

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Invisible shield in space protects Earth from ‘killer electrons’


A cloud of cold, charged gas around Earth, called the plasmasphere and seen here in purple, interacts with the particles in Earth's radiation belts — shown in grey— to create an impenetrable barrier that blocks the fastest electrons from moving in closer to our planet. Image by NASA/Goddard
A cloud of cold, charged gas around Earth, called the plasmasphere and seen here in purple, interacts with the particles in Earth’s radiation belts — shown in grey— to create an impenetrable barrier that blocks the fastest electrons from moving in closer to our planet. These findings were published in Nature magazine on Nov. 26, 2014. Image by NASA/Goddard



Excerpt from pbs.org

A team led by professors and scientists from the University of Colorado at Boulder have discovered an invisible shield in space that blocks Earth from so-called “killer electrons,” according to findings published in Nature on Thursday.

“Somewhat like the shields created by force fields on Star Trek that were used to repel alien weapons, we are seeing an invisible shield blocking these electrons,” said Professor Daniel N. Baker, the lead author of the study in a press release.

“It’s an extremely puzzling phenomenon.”

According to NASA, “killer electrons” are the devilish doppelgangers of Earth’s subatomic allies.

While the flow of electrons is used as electricity to power everything from cell phones to light bulbs, when electrons reach high speeds like that of more than 100,000 miles per second in space, they can become dangerous and have been known to destroy satellites and even injure astronauts.

The shield, said to be located some 7,200 miles from Earth and impenetrable, lies within the Van Allen radiation belts, two rings around Earth containing potent electrons and protons trapped by the Earth’s magnetic field.

In 2008, NASA’s STEREO spacecraft, discovered that electrons turn into speedy, destructive “killer electrons” in part when picked up in the Belts by powerful radio waves known as whistlers.

Luckily though: “It’s almost like theses electrons are running into a glass wall in space,” said Baker of the shield, which was discovered using data collected by NASA’s Van Allen probes.

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Future Tech Watch ~ High-tech mirrors to beam heat from buildings into space ~ May replace air conditioning



illustration of reflective panel on building

news.stanford.edu 

By Chris Cesare

A new ultrathin multilayered material can cool buildings without air conditioning by radiating warmth from inside the buildings into space while also reflecting sunlight to reduce incoming heat.

Stanford engineers have invented a material designed to help cool buildings. The material reflects incoming sunlight, and it sends heat from inside the structure directly into space as infrared radiation (represented by reddish rays).

Stanford engineers have invented a revolutionary coating material that can help cool buildings, even on sunny days, by radiating heat away from the buildings and sending it directly into space.

A team led by electrical engineering Professor Shanhui Fan and research associate Aaswath Raman reported this energy-saving breakthrough in the journal Nature.

The heart of the invention is an ultrathin, multilayered material that deals with light, both invisible and visible, in a new way.

Invisible light in the form of infrared radiation is one of the ways that all objects and living things throw off heat. When we stand in front of a closed oven without touching it, the heat we feel is infrared light. This invisible, heat-bearing light is what the Stanford invention shunts away from buildings and sends into space.

Of course, sunshine also warms buildings. The new material, in addition dealing with infrared light, is also a stunningly efficient mirror that reflects virtually all of the incoming sunlight that strikes it.

The result is what the Stanford team calls photonic radiative cooling – a one-two punch that offloads infrared heat from within a building while also reflecting the sunlight that would otherwise warm it up. The result is cooler buildings that require less air conditioning.

"This is very novel and an extraordinarily simple idea," said Eli Yablonovitch, a professor of engineering at the University of California, Berkeley, and a pioneer of photonics who directs the Center for Energy Efficient Electronics Science. "As a result of professor Fan's work, we can now [use radiative cooling], not only at night but counter-intuitively in the daytime as well."

The researchers say they designed the material to be cost-effective for large-scale deployment on building rooftops. Though still a young technology, they believe it could one day reduce demand for electricity. As much as 15 percent of the energy used in buildings in the United States is spent powering air conditioning systems.

In practice the researchers think the coating might be sprayed on a more solid material to make it suitable for withstanding the elements.

"This team has shown how to passively cool structures by simply radiating heat into the cold darkness of space," said Nobel Prize-winning physicist Burton Richter, professor emeritus at Stanford and former director of the research facility now called the SLAC National Accelerator Laboratory.

A warming world needs cooling technologies that don't require power, according to Raman, lead author of the Nature paper. 

"Across the developing world, photonic radiative cooling makes off-grid cooling a possibility in rural regions, in addition to meeting skyrocketing demand for air conditioning in urban areas," he said.

Using a window into space

The real breakthrough is how the Stanford material radiates heat away from buildings.

researchers Linxiao Zhu, Shanhui Fan, Aaswath Raman
Doctoral candidate Linxiao Zhu, Professor Shanhui Fan and research associate 
Aaswath Raman are members of the team that invented the breakthrough energy-saving material.
As science students know, heat can be transferred in three ways: conduction, convection and radiation. Conduction transfers heat by touch. That's why you don't touch an oven pan without wearing a mitt. Convection transfers heat by movement of fluids or air. It's the warm rush of air when the oven is opened. Radiation transfers heat in the form of infrared light that emanates outward from objects, sight unseen.
The first part of the coating's one-two punch radiates heat-bearing infrared light directly into space. The ultrathin coating was carefully constructed to send this infrared light away from buildings at the precise frequency that allows it to pass through the atmosphere without warming the air, a key feature given the dangers of global warming.

"Think about it like having a window into space," said Fan.

Aiming the mirror

But transmitting heat into space is not enough on its own.
This multilayered coating also acts as a highly efficient mirror, preventing 97 percent of sunlight from striking the building and heating it up.

"We've created something that's a radiator that also happens to be an excellent mirror," said Raman.

Together, the radiation and reflection make the photonic radiative cooler nearly 9 degrees Fahrenheit cooler than the surrounding air during the day.

From prototype to building panel

Making photonic radiative cooling practical requires solving at least two technical problems.

The first is how to conduct the heat inside the building to this exterior coating. Once it gets there, the coating can direct the heat into space, but engineers must first figure out how to efficiently deliver the building heat to the coating.

The second problem is production. Right now the Stanford team's prototype is the size of a personal pizza. Cooling buildings will require large panels. The researchers say there exist large-area fabrication facilities that can make their panels at the scales needed.

The cosmic fridge

More broadly, the team sees this project as a first step toward using the cold of space as a resource. In the same way that sunlight provides a renewable source of solar energy, the cold universe supplies a nearly unlimited expanse to dump heat.

"Every object that produces heat has to dump that heat into a heat sink," Fan said. "What we've done is to create a way that should allow us to use the coldness of the universe as a heat sink during the day."

In addition to Fan, Raman and Zhu, this paper has two additional co-authors: Marc Abou Anoma, a master's student in mechanical engineering who has graduated; and Eden Rephaeli, a doctoral student in applied physics who has graduated.

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Kermit the Frog maybe, but are we really suppossed to believe humans evolved from this guy? Greg Giles


An artist's rendition of the amphibious Cartorhynchus lenticarpus. (Stefano Broccoli)


In a Nov. 5th article penned by Rachel Feltman(washingtonpost.com) entitled Newly discovered fossil could prove a problem for creationists (But apparently not a really big problem), a report published in the journal Nature claims to have discovered the missing link proving that modern man has evolved from a sometimes aquatic, sometimes not, (he apparently changed his mind once or twice about which direction he wanted to evolve) little green fish/frog/alligator/lizardy type character named Cartorhynchus lenticarpus. Although I chuckled all through the unsubstantiated claims of the report's lead author Ryosuke Motani, one of my favorite moments had to be when Motani describes his brainstorming activity. "Initially I was really puzzled by this fossil. I could tell it was related [to ichthyosaurs], but I didn't know how to place it. It took me about a year before I was sure I had no doubts." (Wait Ryosuke, go back to that moment in time while you were kicking an empty soda can around your neighborhood while trying to figure out how you could pound a square green peg into a round hole. I think that's where your theory may have gone slightly askew.)

My absolute favorite moment of the study though had to be the team's conclusion that the foot and a half long green amphibian "probably had a happy life". I could see now a room full of white lab coats concurring with one another. "Yes yes, happy indeed. I concur." A young lab technician then sheepishly speaks up. "I must disagree sirs. My research shows its not easy being green." "Oh yes, yes," the group of senior scientists now concede. "Indeed, it's not easy being green." 

Motani's statement that his team now hopes to find the preceding evolutionary ancestor to Cartorhynchus lenticarpus as their next major breakthrough is the part of this report that I can't get out of my mind. What would the odds be that this small group of researchers not only find one crucial missing link, but will also discover the very next missing piece of the long evolutionary puzzle chain, evidence countless archeologists, scientists and researchers have been, for centuries, turning over stones in search of. Something smells fishy here, and it isn't the great, great, great grandfather of Kermit the Frog.  
Greg Giles

Excerpts from the washingtonpost.com article by Rachel Feltman:

Researchers report that they've found the missing link between an ancient aquatic predator and its ancestors on land. Ichthyosaurs, the dolphin-like reptiles that lived in the sea during the time of the dinosaurs, evolved from terrestrial creatures that made their way back into the water over time.

But the fossil record for the lineage has been spotty, without a clear link between land-based reptiles and the aquatic ichthyosaurs scientists know came after. Now, researchers report in Nature that they've found that link — an amphibious ancestor of the swimming ichthyosaurs named  Cartorhynchus lenticarpus.

"Many creationists have tried to portray ichthyosaurs as being contrary to evolution," said lead author Ryosuke Motani, a professor of earth and planetary sciences at the University of California Davis. "We knew based on their bone structure that they were reptiles, and that their ancestors lived on land at some time, but they were fully adapted to life in the water. So creationists would say, well, they couldn't have evolved from those reptiles, because where's the link?"

Now the gap has been filled, he said.

The creature is about a foot and a half long and lived 248 million years ago.

"Initially I was really puzzled by this fossil," Motani said. "I could tell it was related [to ichthyosaurs], but I didn't know how to place it. It took me about a year before I was sure I had no doubts."

One of the most important differences between this new ichthyosaur and its supposed descendants comes down to being big boned: When other vertebrates have evolved from land to sea living, they've gone through stages where they're amphibious and heavy. Their thick bones probably allowed them to fight the power of strong coastal waves and stay grounded in shallow waters. Sure enough, this new fossil has much thicker bones than previously examined ichthyosaurs.

"This animal probably had a happy life. It was in the tropics, and it was probably a bottom feeder that fed on soft-bodied things like squid and animals like shrimp," Motani said. "And for a predator like that to exist, there has to be plenty of prey. This was probably one of the first predators to appear after that extinction."

This single fossil hasn't revealed all of the ichthyosaurs' secrets. Motani hopes to find the preceding evolutionary ancestor next — one that was also amphibious, but spent slightly more of its time on land. "We're looking for that one now," Motani said.

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Researchers make 32 differently-shaped DNA crystals – is this the future of nanotech?



Researchers have achieved 32 different–shaped crystal structures using the DNA–brick self–assembly method. (Photo : Harvard’s Wyss Institute)

Excerpt from
zmescience.com 

A team at Harvard’s Wyss Institute for Biologically Inspired Engineering demonstrated the latest advances in programmable DNA self-assembly by crystallizing 32 structures with precisely prescribed depths and complex 3D features. The DNA crystals could potentially be used as the basis of a programmable material platform that would allow scientists to build extremely precise and complex structures rivaling the complexity of many molecular machines we see in nature – all from the bottom up!

Nanotechnology like Lego

For the past twenty years or so, there’s been a lot of interest shown into designing large DNA crystals of various desired shapes by exploiting DNA’s inherent ability to self-assemble. We’re recently beginning to see the fruits of this labor, first in 2012 when the same team described their “DNA-brick self-assembly” method that allowed them to build more than 100 3D complex nanostructures about the size of viruses. The 32 designs reported in this latest research are 1000 times larger, close to the size of a speck of dust, which makes them closer to applicable scale where they can be used practically.

With conventional methods of DNA assembly, the resulting design tends to become more and more imperfect as you scale the design because at each step there’s a risk of error. The technique developed at Harvard is different because since it uses short, synthetic strands of DNA that work like interlocking Lego® bricks to build complex structures – it’s a modular design. Each structure first starts off as a computer model of a molecular cube (the master canvas), then individual DNA bricks are removed or added independently until a desired shape is met. These bricks bind to as many as four neighboring strands or bricks. Thus, two bricks connect to one another at a 90-degree angle to form a 3D shape, just like a pair of two-stud Lego bricks. Each individual brick is coded in such a way that they self-assemble in a desired 3-D shape. What’s fantastic is that this method allows for intricate shapes to built on an extremely tiny scale opening up a slew of applications. For instance, a cube built up from 1,000 such bricks (10 by 10 by 10) measures just 25 nanometers in width – thousands of times smaller than the width of a human hair!
“Therein lies the key distinguishing feature of our design strategy—its modularity,” said co-lead author Yonggang Ke, Ph.D., formerly a Wyss Institute Postdoctoral Fellow and now an assistant professor at the Georgia Institute of Technology and Emory University. “The ability to simply add or remove pieces from the master canvas makes it easy to create virtually any design.”

Precision controlled DNA

Most importantly, this modularity allows precision control of the structure’s depth. This is the first time that anyone has been able to design crystal depth with nanometer precision, up to 80 nm, as opposed to  two-dimensional DNA lattices which are typically single-layer structures with only 2 nm depth.
“DNA crystals are attractive for nanotechnology applications because they are comprised of repeating structural units that provide an ideal template for scalable design features”, said co-lead author graduate student Luvena Ong.

 “Peng’s team is using the DNA-brick self-assembly method to build the foundation for the new landscape of DNA nanotechnology at an impressive pace,” said Wyss Institute Founding Director Don Ingber, M.D., Ph.D. “What have been mere visions of how the DNA molecule could be used to advance everything from the semiconductor industry to biophysics are fast becoming realities.”

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