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Taking human-machine interaction to the next level with cloned virtual applications for unlimited users

Taking human-machine interaction to the next level with cloned virtual applications for unlimited users | Amazing Science |

In 2007, Silicon Valley's SRI International formed Siri Inc. to commercialize a virtual personal assistant technology born out of the institute's DARPA-funded CALO (Cognitive Assistant that Learns and Organizes) artificial intelligence project. A free app for the iOS platform was subsequently launched as a public beta in early February 2010, and just a couple of months later, Apple acquired the company. Spin forward to October 2011, and a conversational search assistant called Siri was launched as a new feature for the iPhone 4S.


A little while later, Google premiered its own digital PA in Android 4.1 (Jelly Bean). In addition to providing Siri-like search and assistance using natural language, Google Now delivered information and suggestions based on actions or decisions that the user had previously taken. SRI's latest project, bRight, progresses beyond both systems as an answer to what's been dubbed cognitive overload, where the tidal wave of information that can flood in during emergency situations can prove to be just too much to deal with effectively and, perhaps more importantly, rapidly.


The research prototype uses face recognition (though more secure biometrics, such as iris scans, will likely be implemented in the future) and gaze monitoring systems, along with proximity, gesture and touch sensors, to build detailed user profiles. In a similar way that modern computers might make valuable performance gains by effectively taking a shortcut when certain conditions are met, bRight's powerful AI software uses this information to anticipate what might be needed so that only data that's relevant to the job in hand is presented to the user, necessary tools can be literally placed at a user's fingertips, and repetitive tasks can be fully or partly automated.


For example, at a fairly simple level, if a user highlights a word in a document, the system can guess which menu items might be needed next and present the user with likely choices. Or if someone's writing a specific kind of email, such as a staff newsletter or performance bulletin, bRight may be able to determine its recipients based on previous activity, and pre-populate the Send To field. It might also detect potential errors or breaches of standard protocol.


"If bRight recognizes a user's action to be of a certain class, then it could provide corrective action," explains Dr. Grit Denker of SRI's Computer Science Laboratory. "Say I am writing an email about new bRight ideas and I am sending it to a bunch of people. bRight could recognize that I usually first send this to an internal team, before sending it to outside folks. Thus, if I am about to send such an email without having first sent it to my team, bRight could notify me whether this is on purpose."


 "bRight combines semantic markup in the application layer with sensors at the observation layer (e.g., touch, gaze, gesture, etc.)," says Denker. "This combination provides higher precision for prediction, especially in an environment where you do not necessarily have days or months of training data. In order to be useful, it has to have high accuracy. This can only be achieved if the cognitive models we intend to build are tuned to the applications. We are currently working on developing a cognitive model of users in the cyber domain using our tools. We are very interested in finding partners who would work with us to instantiate bRight for domains that meet at least two of the following criteria: information overload, rapid decision making and execution, and the need for collaboration."

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A new form of carbon: Grossly warped 'nanographene'

A new form of carbon: Grossly warped 'nanographene' | Amazing Science |
Chemists at Boston College and Nagoya University in Japan have synthesized the first example of a new form of carbon, the team reports in the most recent online edition of the journal Nature Chemistry.


Graphite, the most stable form of elemental carbon, consists of pure carbon sheets stacked upon one another like reams of paper. Individual sheets, known as graphene, prefer planar geometries as a consequence of the hexagonal honeycomb-like arrangements of trigonal carbon atoms that comprise their two-dimensional networks. Defects in the form of non-hexagonal rings in such networks cause distortions away from planarity.

The new material consists of multiple identical pieces of grossly warped graphene, each containing exactly 80 carbon atoms joined together in a network of 26 rings, with 30 hydrogen atoms decorating the rim. Because they measure slightly more than a nanometer across, these individual molecules are referred to generically as "nanocarbons," or more specifically in this case as "grossly warped nanographenes."

Until recently, scientists had identified only two forms of pure carbon: diamond and graphite. Then in 1985, chemists were stunned by the discovery that carbon atoms could also join together to form hollow balls, known as fullerenes. Since then, scientists have also learned how to make long, ultra-thin, hollow tubes of carbon atoms, known as carbon nanotubes, and large flat single sheets of carbon atoms, known as graphene. The discovery of fullerenes was awarded the Nobel Prize in Chemistry in 1996, and the preparation of graphene was awarded the Nobel Prize in Physics in 2010.

Graphene sheets prefer planar, 2-dimensional geometries as a consequence of the hexagonal, chicken wire-like, arrangements of trigonal carbon atoms comprising their two-dimensional networks. The new form of carbon just reported in Nature Chemistry, however, is wildly distorted from planarity as a consequence of the presence of five 7-membered rings and one 5-membered ring embedded in the hexagonal lattice of carbon atoms.


Odd-membered-ring defects such as these not only distort the sheets of atoms away from planarity, they also alter the physical, optical, and electronic properties of the material, according to one of the principle authors, Lawrence T. Scott, the Jim and Louise Vanderslice and Family Professor of Chemistry at Boston College.


"Our new grossly warped nanographene is dramatically more soluble than a planar nanographene of comparable size," said Scott, "and the two differ significantly in color, as well. Electrochemical measurements revealed that the planar and the warped nanographenes are equally easily oxidized, but the warped nanographene is more difficult to reduce."


Graphene has been highly touted as a revolutionary material for nanoscale electronics. By introducing multiple odd-membered ring defects into the graphene lattice, Scott and his collaborators have experimentally demonstrated that the electronic properties of graphene can be modified in a predictable manner through precisely controlled chemical synthesis.

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Bacteria have evolved specific cell-cell communication systems allowing them to build up cooperative networks

Bacteria have evolved specific cell-cell communication systems allowing them to build up cooperative networks | Amazing Science |

LMU microbiologist PD Dr. Ralf Heermann and Professor Helge Bode of the Goethe-University in Frankfurt have just reported the discovery of a previously unknown bacterial "language". Their findings are detailed in the latest issue of the journal Nature Chemical Biology. "Our results demonstrate that bacterial communication is much more complex than has been assumed to date," Heermann says.


The bacterial communication system that is currently best understood uses N-acylhomoserine lactones (AHLs) as signals. These compounds are made by enzymes that belong to the group of LuxI-family synthases. Transmitting cells secrete the signal and neighboring cells recognize the concentration via a LuxR-type receptor. Signal perception changes the pattern of gene expression in the receiving cells, which results in alterations in their functional properties or behavior. However, many bacteria have LuxR receptors but lack any LuxI homolog, so that they cannot produce AHLs. These receptors are referred to as LuxR solos.


Ralf Heermann and Helge Bode have now discovered a type of ligand that binds to LuxR solos. As model system, they chose the species Photorhabdus luminescens, a pathogenic bacterium that is lethal to insects.


"We have identified a new class of bacterial signaling molecules, which are produced by a previously unknown biochemical route," explains Helge Bode, Merck Professor of Molecular Biotechnology at Goethe-Universität Frankfurt. It turns out that a LuxR solo of this bacterium responds to compounds called alpha-pyrones, specifically to photopyrones. Furthermore, the researchers have identified the pyrone synthase (PpyS) that catalyzes the biosynthesis of photopyrones. The pyrone-based signaling system allows the bacteria to recognize one another, whereupon they produce a surface factor that causes cell clumping. Heermann and Bode assume that this collective behavior makes the cells less vulnerable to the insect's innate immune system, and then allows them to kill their victims by the production of various of toxins." P. luminescens is a useful model organism, because it is related to many human pathogens, including coliform bacteria such as enterohemorrhagic E. coli (EHEC) and well as plague bacteria," Heermann points out.


Reegan Bourgeois's curator insight, July 16, 2013 1:11 PM

I'm curious if people will file this under "only for bacteria" due to the way the article is written. Perhaps there are implications in a larger scope?

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Amazing Science: Material Science Postings

Amazing Science: Material Science Postings | Amazing Science |

Materials science, also known as materials engineering, is an interdisciplinary field applying the properties of matter to various areas of science and engineering. This relatively new scientific field investigates the relationship between the structure of materials at atomic or molecular scales and their macroscopic properties. It incorporates elements of applied physics and chemistry. With significant media attention focused on nanoscience and nanotechnology in recent years, materials science is becoming more widely known as a specific and unique field of science and engineering.

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Everything is programmable: The future of cybernetically enhanced senses

Everything is programmable: The future of cybernetically enhanced senses | Amazing Science |

We’re in the midst of a bionic revolution, yet most of us don’t know it. One of the definitions of sanity is the ability to tell real from unreal.


Robotics, Cyborgs, Augmented Reality, Synthetic Biology, Artificial Intelligence, and human enhancement technologies are only some of the fields, which are changing the ‘situation’ to which we need construct a new model of reality.


The world to which we were accustomed and through which we ‘made sense’ and constructed awareness to is no longer.


We may not realize the immediate implications of these technologies, but make no mistake, as soon as sense extensions become a widespread phenomena (and we believe that is soon) our Situational awareness will change accordingly and the theory of mind we each construct and carry will be altered irrevocably.

Reegan Bourgeois's curator insight, July 16, 2013 1:57 PM

I find this hitting far too close to home based on some personal observations. I wonder how many other people have noticed similar events.

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Swedish research study shows that heart beats synchronize when people sing together in a choir

Swedish research study shows that heart beats synchronize when people sing together in a choir | Amazing Science |
When members of a choir sing, their heart rates quickly become synchronized, beating in the same rhythm. Researchers think this may be why singing together is a key part of religious rituals around the world, and such a joy for the singers.
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Novel quantum dot-based technique sees 100 different molecules simultaneously in a single cell

Novel quantum dot-based technique sees 100 different molecules simultaneously in a single cell | Amazing Science |

Study of normal cell physiology and disease pathogenesis heavily relies on untangling the complexity of intracellular molecular mechanisms and pathways. To achieve this goal, comprehensive molecular profiling of individual cells within the context of microenvironment is required. New research from the University of Washington offers a more comprehensive way of analyzing a single cell’s unique behavior and could reveal patterns that indicate why a cell will or will not become malignant.

Xiaohu Gua and graduate student Pavel Zrazhevskiy have used an array of distinctly colored quantum dots to illuminate 100 biomarkers, a ten-fold increase from the current research standard, to help analyze individual cells from cultures or tissue biopsies. The investigators published their findings in the journal Nature Communications ("Quantum dot imaging platform for single-cell molecular profiling"). While other approaches have measured multiple biomarkers in a single cell, what makes this technique so promising is that it reuses the same precious tissue sample in a cyclical process to measure 100 biomolecules in groups of ten. The process starts by pairing a commercially available antibody that is known to bind with specific biomolecule with a quantum dot of distinct size and therefore color. The investigators then inject a solution of ten of these antibody-quantum dot pairs onto a tissue sample and use a fluorescence microscope to quantify which of the constructs bind at the single cell level.Once the measurement is complete, they then wash the tissue sample with a fluid of detergents at low pH to get rid of the antibodies and quantum dots without degrading the tissue sample. The two investigators have shown that they can repeat this process at least ten times without producing any signs of tissue damage.The researchers note that because this methodology uses commercially available enzymes and standard fluorescence microscopes, it is relatively low cost. They also plan to automate the procedure using microfluidics and automated image processing technologies.

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Used contact lens solution hosts complete ecosystem of microbes and viruses

Used contact lens solution hosts complete ecosystem of microbes and viruses | Amazing Science |
"Virus factories" and more are found in an amoeba within contact lens fluid.


In July of last year, researchers in France described a rather disturbing example of what could happen if you're not careful about cleaning your contact lenses. A 17-year-old patient had been wearing monthly lenses well past their expiration date, and rinsing them with a cleaning solution she'd diluted with tap water. The end result was an eye infection. Luckily, a bit of care managed to clear it up.


In the meantime, the people who treated her dumped some of the solution out of her contact lens case and started trying to culture any parasites that would grow out of it. In the end, they got an entire ecosystem—all contained inside a single strain of amoeba. Among the parasites-within-parasites were a giant virus, a virus that targets that virus, and a mobile piece of DNA that can end up inserting into either of them.


When they first grew the amoeba from the contact lens cleaning solution, they found it contained two species of bacteria living inside it. But they also found a giant virus, which they called Lentille virus. These viruses have been known for a while, and they tend to affect amoebas, so this wasn't a huge surprise.


More recently, however, researchers discovered these viruses can get viruses. Or, more precisely, virophages. Upon infecting an amoeba, the giant virus builds what's become called a "virus factory" within the cell, where its genetic material is copied and new viruses are built from parts encoded by its genes. The virophages can spread from amoeba to amoeba, but once they enter the cell, they head straight for the virus factory, where they get replicated.


When the scientists sequenced the genome of the Lentille virus, it had a few surprises for them. To begin with, it contained a new virophage of its own, which they called Sputnik 2. An infected amoeba would release virophage particles, suggesting that the virus could move between these organisms on its own. But the authors also found a copy of the virus inserted into the giant Lentille virus genome. And, if an amoeba were infected with one of these giant viruses, it would also start producing the virophage.


In other words, the virophage has two ways of spreading. Like any other virophage, it can spread from amoeba to amoeba, and will find a home in any that also contain a Lentille virus. But once it finds one, it inserts itself into its giant viral genome, ensuring that any future amoeba it infects gets a copy of the virophage, too. Although it has a preference to jump into the giant virus genome, it can hop elsewhere. That could potentially cause mutations and speed up the evolution of its host.


But that wasn't the only parasite the authors found in Lentille virus. A shorter sequence, one containing six genes, was also associated with the viral genome. As with the virophage, this sequence was found as both a free-standing piece of DNA and inserted into the genome of the Lentille virus. But there was a rather significant difference: none of the genes it carried encoded the sorts of proteins that are used to package a virus. Instead, it had several features normally found in transposons, mobile genetic elements that hop around the genomes of organisms ranging from bacteria to mammals.


As if there weren't enough names to deal with, the authors deemed this DNA element a "transpoviron," for a transposon that targets a virus. They showed that, shortly after an infection with a Lentille virus, its resident transpoviron would be copied out of its host genome, form into circle, and start making copies of itself. These copies were then available to insert into genomes of any other viruses that were around—there's even some evidence that a copy inserted into Sputnik 2 in the past.


By looking at the sequences of some other giant viruses, they also concluded that Lentille virus isn't alone in carrying these molecular parasites.


The authors conclude by painting a picture of the giant viruses as supporting an entire DNA-based ecosystem of mobile genetic elements, which spread to other amoebas (and other viruses) by a variety of means. Given that we've found so much so shortly after starting to look, the authors suggest that we've likely only scratched the surface of its diversity.

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39,000-year-old Frozen Woolly Mammoth on Display in Japan

A frozen woolly mammoth named Yuka goes on display in Japan. The female was found in Russia and was 10 years old when she died. Scientists have made several unsuccessful attempts to revive the species. But mammoth expert Norihisa Inuzuka says Yuka should provide more information about these creatures.

Norihisa Inuzuka, mammoth expert, saying (Japanese): "With this, we can dig deeper into the reasons why species became extinct and apply the lessons learnt to the human race which might be facing its own dangers of extinction. I think it can help us learn to reflect more deeply about our own existence."

What makes the carcass special is that it is extraordinarily well-preserved with presence of liquid blood in it along with pink flesh and fur. The blood, according to scientists, could be used to clone the animal.

"When we broke the ice beneath her stomach, the blood flowed out from there, it was very dark. This is the most astonishing case in my entire life. How was it possible for it to remain in liquid form? And the muscle tissue is also red, the colour of fresh meat," Semyon Grigoryev, the head of the expedition that found Yuki said.


Yuka's lower part is well-preserved as it ended up in a swamp before it froze, but its head along with back show signs of gnawing, Grigoryev added.


Mammoths are an extinct group of elephants that belong to the genus Mammuthus. Their ancestors had migrated from Africa about 3.5 million years back. The most famous of these ancient elephants is the woolly mammoth Mammuthus primigenius, which is a close cousin of the modern elephant. The woolly mammoth appeared in the northeastern Siberia around 400,000 years back and was well-adapted to cold with dense fur, short ears and a dense undercoat.


The exhibition runs from July 13th to September 16th.

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First floating nuclear power plant to be built in Russia

First floating nuclear power plant to be built in Russia | Amazing Science |

The general director of one of Russia's largest shipbuilders, Aleksandr Voznesensky, has announced to reporters that a floating nuclear power plant is currently under construction at one of Russia's ship yards. He added that it will likely be ready for use by 2016. The Russians are calling it a "floating power" station, abbreviated to PEB. The vessel has been given the name Akademik Lomonosov.

Several countries, including the United States and China have considered building floating nuclear power plants but until now, no other known vessels have reached the construction phase. The advantages of a floating nuclear power station are obvious—electrical power could be brought to areas that are not currently being served by other means. Russia in particular has many far-flung outposts in its eastern region that have had difficulty flourishing due to the financial constraints of building power plants so far away from everything else.

The Akademik Lomonosov will have two KLT-40 naval propulsion reactors modified to serve as power providers for an external location—with a displacement of 21,500 tons. Lomonosov noted that nuclear powered marine vessels have a proven safety record going back 50 years. Many nations now routinely deploy nuclear powered ships, submarines and even ice-breakers. He also stressed that the design of the vessel will be such that the platform will be capable of withstanding a tsunami or even a collision with land or a ship. The Akademik Lomonosov will not be able to power itself however, which means it will be towed to wherever it's needed. The vessel will be operated by a crew of 69 people and will also conform to regulations set by the International Atomic Energy Agency.

Lomonosov said that plans are underway to build a fleet of the floating platforms to provide cities and towns across Russia with electricity for general use and more specifically for heating homes and businesses. The Akademik Lomonosov will be capable of generating 70 MW of electricity—enough to power a city of 200,000 people. He noted also that such vessels could also be used to power desalination plants, providing 240,000 cubic meters of fresh water daily.

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'Muscle mesh' revealed: Bulging biceps get their power from a mesh arrangement of cells rather than long ropes

'Muscle mesh' revealed: Bulging biceps get their power from a mesh arrangement of cells rather than long ropes | Amazing Science |
Scientists have discovered a new truth behind big muscles, turning 50 years of knowledge on its head.


Bulging biceps get their power from a mesh arrangement of cells rather than long ropes, detailed studies reveal. As muscles flex, tugging filaments fan out in a lattice, say the University of Washington team who made the breakthrough. This generates force in multiple directions, not just up and down the muscle, Proceedings B journal reports.


This aspect of muscle force generation has flown under the radar for decades and is now becoming a critical feature of our understanding of normal and pathological aspects of muscle.” And it's not just biceps that use this force - all muscles, including the heart appear to do it.


Prof. Thomas Daniel, one of the researchers, said: "This aspect of muscle force generation has flown under the radar for decades and is now becoming a critical feature of our understanding of normal and pathological aspects of muscle."


The basics of how muscle generates power remain the same - filaments of myosin tug on filaments of actin to shorten or contract the muscle. But myosin doesn't tug in one direction, as previously thought. Instead, it pulls at angles and this gives radial force.


The news will be of interest to bodybuilders who strive to max their muscle power, but could also help doctors treating heart problems. Michael Regnier said: "In the heart especially, because the muscle surrounds the chambers that fill with blood, being able to account for forces that are generated in several directions during muscle contraction allows for much more accurate and realistic study of how pressure is generated to eject blood from the heart.


"The radial and long axis forces that are generated may be differentially compromised in cardiac diseases and these new, detailed models allow this to be studied at a molecular level for the first time."

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NASA: Hidden Magnetic Portals Around Earth

A favorite theme of science fiction is "the portal"--an extraordinary opening in space or time that connects travelers to distant realms. A good portal is a shortcut, a guide, a door into the unknown. If only they actually existed....

It turns out that they do, sort of, and a NASA-funded researcher at the University of Iowa has figured out how to find them.

"We call them X-points or electron diffusion regions," explains plasma physicist Jack Scudder of the University of Iowa. "They're places where the magnetic field of Earth connects to the magnetic field of the Sun, creating an uninterrupted path leading from our own planet to the sun's atmosphere 93 million miles away."

Observations by NASA's THEMIS spacecraft and Europe's Cluster probes suggest that these magnetic portals open and close dozens of times each day. They're typically located a few tens of thousands of kilometers from Earth where the geomagnetic field meets the onrushing solar wind. Most portals are small and short-lived; others are yawning, vast, and sustained. Tons of energetic particles can flow through the openings, heating Earth's upper atmosphere, sparking geomagnetic storms, and igniting bright polar auroras.

NASA is planning a mission called "MMS," short for Magnetospheric Multiscale Mission, due to launch in 2014, to study the phenomenon. Bristling with energetic particle detectors and magnetic sensors, the four spacecraft of MMS will spread out in Earth's magnetosphere and surround the portals to observe how they work.

Just one problem: Finding them. Magnetic portals are invisible, unstable, and elusive. They open and close without warning "and there are no signposts to guide us in," notes Scudder.

Actually, there are signposts, and Scudder has found them.

Portals form via the process of magnetic reconnection. Mingling lines of magnetic force from the sun and Earth criss-cross and join to create the openings. "X-points" are where the criss-cross takes place. The sudden joining of magnetic fields can propel jets of charged particles from the X-point, creating an "electron diffusion region."

To learn how to pinpoint these events, Scudder looked at data from a space probe that orbited Earth more than 10 years ago.

"In the late 1990s, NASA's Polar spacecraft spent years in Earth's magnetosphere," explains Scudder, "and it encountered many X-points during its mission."

Data from NASA's Polar spacecraft, circa 1998, provided crucial clues to finding magnetic X-points. Credit: NASABecause Polar carried sensors similar to those of MMS, Scudder decided to see how an X-point looked to Polar. "Using Polar data, we have found five simple combinations of magnetic field and energetic particle measurements that tell us when we've come across an X-point or an electron diffusion region. A single spacecraft, properly instrumented, can make these measurements."

This means that single member of the MMS constellation using the diagnostics can find a portal and alert other members of the constellation. Mission planners long thought that MMS might have to spend a year or so learning to find portals before it could study them. Scudder's work short cuts the process, allowing MMS to get to work without delay.

It's a shortcut worthy of the best portals of fiction, only this time the portals are real. And with the new "signposts" we know how to find them.

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Astronomers witness birth of Milky Way's most massive star

Astronomers witness birth of Milky Way's most massive star | Amazing Science |

Scientists have observed in unprecedented detail the birth of a massive star within a dark cloud core about 10,000 light years from Earth.

The team used the new ALMA (Atacama Large Millimetre/submillimetre Array) telescope in Chile – the most powerful radio telescope in the world – to view the stellar womb which, at 500 times the mass of the Sun and many times more luminous, is the largest ever seen in our galaxy.

The researchers say their observations – to be published in the journal Astronomy and Astrophysics – reveal how matter is being dragged into the centre of the huge gaseous cloud by the gravitational pull of the forming star – or stars – along a number of dense threads or filaments.

"The remarkable observations from ALMA allowed us to get the first really in-depth look at what was going on within this cloud," said lead author Dr Nicolas Peretto, from Cardiff University. "We wanted to see how monster stars form and grow, and we certainly achieved our aim. One of the sources we have found is an absolute giant—the largest protostellar core ever spotted in the Milky Way!

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Computer now as smart as a 4-year-old

Computer now as smart as a 4-year-old | Amazing Science |
Artificial and natural knowledge researchers at the University of Illinois at Chicago have IQ-tested one of the best available artificial intelligence systems to see how intelligent it really is.


Turns out–it's about as smart as the average 4-year-old, they will report July 17 at the U.S. Artificial Intelligence Conference in Bellevue, Wash.


The UIC team put ConceptNet 4, an artificial intelligence system developed at M.I.T., through the verbal portions of the Weschsler Preschool and Primary Scale of Intelligence Test, a standard IQ assessment for young children.

They found ConceptNet 4 has the average IQ of a young child. But unlike most children, the machine's scores were very uneven across different portions of the test.


"If a child had scores that varied this much, it might be a symptom that something was wrong," said Robert Sloan, professor and head of computer science at UIC, and lead author on the study.


Sloan said ConceptNet 4 did very well on a test of vocabulary and on a test of its ability to recognize similarities.


"But ConceptNet 4 did dramatically worse than average on comprehension—the 'why' questions," he said.


One of the hardest problems in building an artificial intelligence, Sloan said, is devising a computer program that can make sound and prudent judgment based on a simple perception of the situation or facts–the dictionary definition of commonsense.


Commonsense has eluded AI engineers because it requires both a very large collection of facts and what Sloan calls implicit facts–things so obvious that we don't know we know them. A computer may know the temperature at which water freezes, but we know that ice is cold.


"All of us know a huge number of things," said Sloan. "As babies, we crawled around and yanked on things and learned that things fall. We yanked on other things and learned that dogs and cats don't appreciate having their tails pulled." Life is a rich learning environment.


"We're still very far from programs with commonsense–AI that can answer comprehension questions with the skill of a child of 8," said Sloan. He and his colleagues hope the study will help to focus attention on the "hard spots" in AI research.

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New genetic test distinguishing between viral and bacterial infections could stop wrongly prescribed antibiotics

New genetic test distinguishing between viral and bacterial infections could stop wrongly prescribed antibiotics | Amazing Science |

By differentiating between bacterial and viral fevers, a new test may help doctors decide whether to prescribe antibiotics.


Fevers are a common symptom of many infectious diseases, but it can be difficult to tell whether viruses or bacteria are the cause. By measuring gene activity in the blood of 22 sick children, Gregory Storch, a pediatrician and infectious disease researcher at Washington University in St. Louis and colleagues were able to distinguish bacteria-sparked fevers from ones kindled by viruses. The activity of hundreds of genes changed as the children’s immune systems responded to the pathogens, but the team found that gauging the response of just 18 genes could correctly distinguish between viral and bacterial infections about 90 percent of the time. The gene activity test could also determine, for viral infections, which specific microbes caused the illness, the team reports July 15 in the Proceedings of the National Academy of Sciences.


Storch’s technique isn’t ready for the clinic; for one thing, it takes days to do the assay and doctors need answers much sooner. But Storch says he’s working to develop a test that could be used in hospitals and doctor’s offices.


The research is a step toward improving diagnosis, says Octavio Ramilo, a pediatric infectious disease specialist at Ohio State University and Nationwide Children’s Hospital in Columbus, who has done similar work. In the future, being able to quickly determine the cause of fevers should help prevent unnecessary antibiotic prescriptions, he says. Antibiotics kill bacteria, but do nothing to fight viruses. Improper antibiotic use has been linked to bacterial resistance to the drugs.

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Multifunctional Genes: Taste Receptor Gene Inactivation Causes Male Sterility

Multifunctional Genes: Taste Receptor Gene Inactivation Causes Male Sterility | Amazing Science |
Two proteins called TAS1R3 and GNAT3, which have been previously known to be involved in oral taste detection, also play a crucial role in sperm development.


While breeding mice for taste-related studies, Dr Bedrich Mosinger from Monell Chemical Senses Center and his colleagues discovered that they were unable to produce offspring that were simultaneously missing two taste-signaling proteins – TAS1R3 and GNAT3.


TAS1R3 is a component of both the sweet and umami (amino acid) taste receptors. GNAT3 is a molecule needed to convert the oral taste receptor signal into a nerve cell response.


The researchers determined that fertility was affected only in males. Both taste proteins had previously been found in testes and sperm, but until now, their function there was unknown.


This study “highlights a connection between the taste system and male reproduction. It is one more demonstration that components of the taste system also play important roles in other organ systems,” Dr Mosinger explained.

 In order to explore the reproductive function of TAS1R3 and GNAT3, the team engineered mice that were missing genes for the mouse versions of the two proteins but expressed the human form of the TAS1R3 receptor – these mice were fertile. 


However, when the human TAS1R3 was blocked in the engineered mice by adding the drug clofibrate to their diet, thus leaving the mice without any functional TAS1R3 or GNAT3 proteins, the males became sterile due to malformed and fewer sperm.


The sterility was quickly reversed after clofibrate was removed from the diet.

Clofibrate belongs to a class of drugs called fibrates that frequently are prescribed to treat lipid disorders such as high blood cholesterol or triglycerides. Previous studies had revealed that it is a potent inhibitor of the human, but not mouse, TAS1R3 receptor.


“Noting the common use of fibrates in modern medicine and also the widespread use in modern agriculture of the structurally-related phenoxy-herbicides, which also block the human TAS1R3 receptor,” Dr Mosinger said, “these compounds could be negatively affecting human fertility, an increasing problem worldwide.”


“If our pharmacological findings are indeed related to the global increase in the incidence of male infertility, we now have knowledge to help us devise treatments to reduce or reverse the effects of fibrates and phenoxy-compounds on sperm production and quality. This knowledge could further be used to design a male non-hormonal contraceptive,” Dr Mosinger concluded.

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4D Printing is Manufacturing’s Next Frontier: Materials That Assemble Themselves

4D Printing is Manufacturing’s Next Frontier: Materials That Assemble Themselves | Amazing Science |

The first proof of concept came from a just-add-H20 molecules experiment: a strand of unformed printed pieces that morphed into the MIT logo once submerged in water. Everything was programmed ahead of time, so that it only took a change in elements (the water) to create a new shape, and therefore a new product.


The potential effect of such shape-shifting powers is limitless on everything from consumer goods to biomedical practices, the aerospace industry to sports. “You can imagine garments or shoes that respond to the athlete and the environment," Tibbits tells Co.Design. "Tires could respond to road conditions, rather than consumers needing different tires for different surfaces.”


For him, the ultimate goal is on a macro scale--applying 4-D printing to reduce energy and labor costs in manufacturing.


The 4-D process requires two kinds of materials: static and active. The static material acts as the geometric structure, and the active material contains the energy and information that prompts the object’s transformation. Tibbits designs the size and placement of the active material using Autodesk’s Project Cyborg software. A Connex Multi-Material printer from Stratasys will then deposit the two materials simultaneously.


Of course, MIT scored a major coup in making objects that bounce into new forms once underwater. And along with the team’s largest future plans for the technology--to change the shape of global manufacture--you can also see how less ambitious iterations would refine or even lead into extinction the user experience of say, assembling furniture from Ikea.

Charlotte Jansen's curator insight, May 6, 12:32 AM

4D Printing - is this the future of manufacturing?

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Ancient life, potentially millions of years old and barely alive, found 100 feet beneath ocean floor

Ancient life, potentially millions of years old and barely alive, found 100 feet beneath ocean floor | Amazing Science |
Researchers have found bacteria beneath the Pacific floor that may be thousands or millions of years old, their metabolism so slow that they’re basically in a state of suspended animation.


Call it survival of the slowest: Extraordinarily old, bizarrely low-key bacteria have been found in sediments 100 feet below the sea floor of the Pacific Ocean, far removed from sunlight, fresh nutrients and what humans would consider anything interesting to do.


Some of these organisms, scientists say, could be at least 1,000 years old. Or maybe millions of years. Their strategy for staying alive is to be barely alive at all. Their metabolism is dialed down to almost nothing, an adaptive advantage in a place with so few resources. The bacteria that survive are the ones that can satisfy themselves with minute traces of oxygen and a parsimonious diet of organic material laid down millions of years ago.


Such buried bacteria have been found before, but a new study, published Thursdayonline by the journal Science, has provided the clearest look at their glacial pace of existence. The conclusion, in short, is that microbes can putter along at extremely low rates of oxygen respiration, their numbers limited only by the paucity of energy available in the buried sediment.


“These organisms live so slowly that when we look at it at our own time scale, it’s like suspended animation,” said Danish scientist Hans Roy, a biologist at Aarhus University and the lead author of the study. “The main lesson here is that we need to stop looking at life at our own time scale.”

An ancillary message is that human beings should not be too chauvinistic about what constitutes, or characterizes, a living thing.


There are a lot more nuances to nature than scientists realized just a few decades ago.


The ingenuity of life gives hope to researchers looking for evidence of life beyond Earth. Extraterrestrial life could conceivably be detected by robotic probes, for example, in the Martian subsurface, or in an ice-
covered ocean on a cold moon farther out in the solar system.

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Graphene could deliver internet 100 times faster, study shows

Graphene could deliver internet 100 times faster, study shows | Amazing Science |

In a paper published in Physical Review Letters, researchers from the Centre for Graphene Science at the Universities of Bath and Exeter have demonstrated for the first time incredibly short optical response rates using graphene, which could pave the way for a revolution in telecommunications.


Every day large amounts of information is transmitted and processed through optoelectronic devices such as optical fibres, photodetectors and lasers. Signals are sent by photons at infrared wavelengths and processed using optical switches, which convert signals into a series of light pulses.

Ordinarily optical switches respond at rate of a few picoseconds – around a trillionth of a second. Through this study physicists have observed the response rate of an optical switch using ‘few layer graphene’ to be around one hundred femtoseconds – nearly a hundred times quicker than current materials.


Graphene is just one atom thick, but remarkably strong. Scientists have suggested that it would take an elephant, balanced on a pencil to break through a single sheet. Already dubbed a miracle material due to its strength, lightness, flexibility, conductivity and low cost, it could now enter the market to dramatically improve telecommunications.


Commenting on the report’s main findings, lead researcher Dr, Enrico Da Como said: “We’ve seen an ultrafast optical response rate, using ‘few-layer graphene’, which has exciting applications for the development of high speed optoelectronic components based on graphene. This fast response is in the infrared part of the electromagnetic spectrum, where many applications in telecommunications, security and also medicine are currently developing and affecting our society.”


Co-Director of the Centre for Graphene Science at Bath, Professor Simon Bending added: “The more we find out about graphene the more remarkable its properties seem to be. This research shows that it also has unique optical properties which could find important new applications.”

In the long term this research could also lead to the development of quantum cascade lasers based on graphene. Quantum cascade lasers are semiconductor lasers used in pollution monitoring, security and spectroscopy. Few-layer graphene could emerge as a unique platform for this interesting application.

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Hubble Space Telescope determined visible color of the first exoplanet (HD 189733b) - and it is BLUE!

Hubble Space Telescope determined visible color of the first exoplanet (HD 189733b) - and it is BLUE! | Amazing Science |
Hubble Space Telescope measures visible light from an exoplanet.


A navy-blue world orbiting a faraway star is the first exoplanet to have its color directly measured. Discovered in 2005, HD 189733b is one of the best-studied planets outside the Solar System, orbiting a star about 19 parsecs away in the Vulpecula, or Fox, constellation. Previous efforts to observe the planet focused on the infrared light it emits — invisible to the human eye.

Last December, astrophysicist Tom Evans at the University of Oxford, UK, and his colleagues used the Hubble Space Telescope to observe the planet and its host star. Hubble's optical resolution is not high enough to actually 'see' the planet as a dot of light separate from its star, so instead, the telescope receives light from both objects that mix into a single point source. To isolate the light contribution of the planet, Evans and his colleagues waited for the planet to move behind the star during its orbit, so that its light would be blocked, and looked for changes in light color.


A spectrograph on board the Hubble monitored light coming from the source, in wavelengths ranging from yellow to ultraviolet. During the eclipse, the amount of observed blue light decreased, whereas other colours remained unaffected. This indicated that the light reflected by the planet's atmosphere, blocked by the star in the eclipse, is blue. The team reports its findings in the 1 August 2013 issue of Astrophysical Journal Letters.


"This is the first time this has been done for optical wavelengths," said Alan Boss, an astrophysicist at the Carnegie Institution for Science in Washington DC. "It's a technical tour de force." The amount of visible light bouncing off a planet is typically small compared to light fluctuations in a star, making planets difficult to distinguish. Fortunately, HD 189733b is large relative to other exoplanets — and well illuminated.


Although the planet seems to be the shade of a deep ocean, it is unlikely to host liquid water. The exoplanet is a giant ball of gas, similar to Jupiter, and was previously often painted brown and red in artists' impressions.


The blue color may come from clouds laden with reflective particles that contain silicon — essentially raindrops of molten glass. Evidence for this idea dates to 2007, when Hubble observed the planet passing in front of its star. Light from the star seemed to be passing through a haze of particles.


"Our best theory points to a layer of clouds deep in the planet's atmosphere," says Evans. Clouds at high altitudes would simply reflect every colour back into space, making the planet look white. Light bouncing off clouds lower in the atmosphere might pass through a layer of sodium that would selectively absorb red light but allow blue light to escape.


But clouds are not the only possible explanation for the blue hue. Jonathan Fortney, an astrophysicist at the University of California, Santa Cruz says that the planet's colour “seems consistent with the scattering of light by hydrogen molecules in the atmosphere".

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Scientists Detect Over 6,000 RNA Transcripts Involved In Memory Storage

Scientists Detect Over 6,000 RNA Transcripts Involved In Memory Storage | Amazing Science |

Despite decades of research, relatively little is known about the identity of RNA molecules that are transported as part of the molecular process underpinning learning and memory.


Now, working together, scientists from the Florida campus of The Scripps Research Institute (TSRI), Columbia University and the University of Florida, Gainesville, have developed a novel strategy for isolating and characterizing a substantial number of RNAs transported from the cell-body of neuron (nerve cell) to the synapse, the small gap separating neurons that enables cell to cell communication.


Using this new method, the scientists were able to identify nearly 6,000 transcripts (RNA sequences) from the genome of Aplysia, a sea slug widely used in scientific investigation.



Sathya Puthanveettil, PhD, is an assistant professor at The Scripps Research institute, Florida campus.


The scientists’ target is known as the synaptic transcriptome—roughly the complete set of RNA molecules transported from the neuronal cell body to the synapse.

In the study, published recently in the journal Proceedings of the National Academy of Sciences, the scientists focused on the RNA transport complexes that interact with the molecular motor kinesin; kinesin proteins move along filaments known as microtubules in the cell and carry various gene products during the early stage of memory storage.


While neurons use active transport mechanisms such as kinesin to deliver RNA cargos to synapses, once they arrive at their synaptic destination that service stops and is taken over by other, more localized mechanisms—in much the same way that a traveler’s bags gets handed off to the hotel doorman once the taxi has dropped them at the entrance.


The scientists identified thousands of these unique sequences of both coding and noncoding RNAs. As it turned out, several of these RNAs play key roles in the maintenance of synaptic function and growth.


The scientists also uncovered several antisense RNAs (paired duplicates that can inhibit gene expression), although what their function at the synapse might be remains unknown.


“Our analyses suggest that the transported RNAs are surprisingly diverse,” said Sathya Puthanveettil, a TSRI assistant professor who designed the study. “It also brings up an important question of why so many different RNAs are transported to synapses. One reason may be that they are stored there to be used later to help maintain long-term memories.”


The team’s new approach offers the advantage of avoiding the dissection of neuronal processes to identify synaptically localized RNAs by focusing on transport complexes instead, Puthanveettil said. This new approach should help in better understanding changes in localized RNAs and their role in local translation as molecular substrates, not only in memory storage, but also in a variety of other physiological conditions, including development.


“New protein synthesis is a prerequisite for maintaining long term memory,” he said, “but you don’t need this kind of transport forever, so it raises many questions that we want to answer. What molecules need to be synthesized to maintain memory? How long is this collection of RNAs stored? What localized mechanisms come into play for memory maintenance? ”

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Just Like Terminator: Scientists Devise Way to build 3-D Structures Out of Liquid Metal

Just Like Terminator: Scientists Devise Way to build 3-D Structures Out of Liquid Metal | Amazing Science |

Through the development of three-dimensional printing technology and techniques, researchers from North Carolina State University have discovered a way to create free-standing structures made of liquid metal at room temperature.


"It's difficult to create structures out of liquids, because liquids want to bead up. But we've found that a liquid metal alloy of gallium and indium reacts to the oxygen in the air at room temperature to form a 'skin' that allows the liquid metal structures to retain their shapes," Michael Dickey, an assistant professor of chemical and biomolecular engineering at NC State and co-author of a paper describing the work, said in a press release.


Throughout the study, the researchers developed multiple techniques for creating these structures that can be used to connect electronic components in three dimensions, including stacking droplets of liquid metal on top of each other like a stack of oranges at the supermarket, they said. Importantly, the droplets adhere to one another, but retain their shape, withstanding the urge to merge into a single, larger droplet.


Another technique injects liquid metal into a polymer template so that the metal takes on a specific shape before the template is then dissolved, leaving the bare, liquid metal in the desired shape.


Furthermore, the researchers developed techniques for creating liquid metal wires able to retain their shape even when held perpendicular to the substrate. 


Going forward, Dickey's team is exploring how to further develop these techniques, as well as devising ways to use them in a variety of electronics and with current 3-D printing technologies. However, despite the fact that Dickey oversaw the work, the main driving force, he says, was someone else entirely. "I'd also like to note that the work by an undergraduate, Collin Ladd, was indispensable to this project," Dickey says. "He helped develop the concept, and literally created some of this technology out of spare parts he found himself."

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Heat radiation of smallest objects: Theories beyond Planck's law describe this emission very accurately.

Heat radiation of smallest objects: Theories beyond Planck's law describe this emission very accurately. | Amazing Science |
Objects that are smaller than the wavelength of thermal radiation cannot radiate heat efficiently. A generalized theory of thermal radiation has now been experimentally confirmed at the level of a single object at the Vienna University of Technology.


All the objects around us emit thermal radiation. Usually, this radiation can be described very accurately using Planck's law. If, however, the radiating object is smaller than the thermal wavelength, it behaves according to different rules and cannot emit the energy efficiently. This has now been confirmed by a team of researchers at the Vienna University of Technology. These findings are important for heat management of nano-devices and also for the science of aerosols - microparticles suspended in air, which influence the climate.


Max Planck considered bodies which absorb all radiation. Due to the conservation of of energy, radiation has to be re-emitted by the surface. The body's temperature determines at which wavelengths the heat radiation is emitted, and this temperature-dependent wavelength distribution can be predicted with great accuracy using Planck's equations.


"However, things change if the object is smaller than the typical length over which the radiation is absorbed", says Arno Rauschenbeutel. "In that case, the body cannot fully absorb the incoming radiation, part of it can pass through." As a result, the thermal radiation of the body is altered and does not obey Planck's law any more.


Christian Wuttke and Arno Rauschenbeutel sent light through ultra-thin optical fibers with a diameter of only 500 nanometers. They measured the amount of optical energy which was converted into heat and subsequently radiated away into the environment. "We could show that the fibers take much longer to reach their equilibrium temperature than a simple application of Planck's law would suggest", says Arno Rauschenbeutel.


"However, our findings are in perfect agreement with the more general theory of fluctuational electrodynamics, which allows one to take the geometry and the size of the body into account."


Arno Rauschenbeutel's research group is also using ultra-thin optical fibers to transmit quantum information. In this context, a good understanding of the fibers' thermal behavior is very important. A slower cooling process and a less effective heat transport entails a higher risk of the fibers melting and burning out when data is sent through.


More general theories of heat radiation beyond Planck's equations also play an important role in aerosol physics, which deals with tiny particles in the atmosphere. "The thermal radiation of a lump of coal can be described perfectly well by Planck's law, but the behavior of soot particles in the atmosphere can only be described with a more general theory, which we could now further confirm in our experiment", says Arno Rauschenbeutel.

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5D optical memory in glass could record almost eternally lasting evidence of our civilization

5D optical memory in glass could record almost eternally lasting evidence of our civilization | Amazing Science |

Using nanostructured glass, scientists at the University of Southampton have, for the first time, experimentally demonstrated the recording and retrieval processes of five dimensional digital data by femtosecond laser writing. The storage allows unprecedented parameters including 360 TB/disc data capacity, thermal stability up to 1000°C and practically unlimited lifetime.

Coined as the 'Superman' memory crystal, as the glass memory has been compared to the "memory crystals" used in the Superman films, the data is recorded via self-assembled nanostructures created in fused quartz, which is able to store vast quantities of data for over a million years. The information encoding is realised in five dimensions: the size and orientation in addition to the three dimensional position of these nanostructures.

A 300 kb digital copy of a text file was successfully recorded in 5D using ultrafast laser, producing extremely short and intense pulses of light. The file is written in three layers of nanostructured dots separated by five micrometers. The self-assembled nanostructures change the way light travels through glass, modifying polarisation of light that can then be read by combination of optical microscope and a polariser, similar to that found in Polaroid sunglasses.

The research is led by the ORC researcher Jingyu Zhang and conducted under a joint project with Eindhoven University of Technology. "We are developing a very stable and safe form of portable memory using glass, which could be highly useful for organisations with big archives. At the moment companies have to back up their archives every five to ten years because hard-drive memory has a relatively short lifespan," says Jingyu.


"Museums who want to preserve information or places like the national archives where they have huge numbers of documents, would really benefit."


The Physical Optics group from the ORC presented their ground-breaking paper at the photonics industry's renowned Conference on Lasers and Electro-Optics (CLEO'13) in San Jose. The paper, '5D Data Storage by Ultrafast Laser Nanostructuring in Glass' was presented by the during CLEO's prestigious post deadline session.


Professor Peter Kazansky, the ORC's group supervisor, adds: "It is thrilling to think that we have created the first document which will likely survive the human race. This technology can secure the last evidence of civilisation: all we've learnt will not be forgotten."

The team are now looking for industry partners to commercialise this ground-breaking new technology.

Vloasis's curator insight, July 10, 2013 9:20 PM

5-dimensional data at 360 TB per disc?  Newegg, Amazon, are you hearing this?  :)

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Neanderthals shared speech and language with modern humans, study suggests

Neanderthals shared speech and language with modern humans, study suggests | Amazing Science |

Fast-accumulating data seem to indicate that our close cousins, the Neanderthals, were much more similar to us than imagined even a decade ago. But did they have anything like modern speech and language? And if so, what are the implications for understanding present-day linguistic diversity? The MPI for Psycholinguistics researchers Dan Dediu and Stephen C. Levinson argue in their paper in Frontiers in Language Sciences that modern language and speech can be traced back to the last common ancestor we shared with the Neandertals roughly half a million years ago.


The Neanderthals have fascinated both the academic world and the general public ever since their discovery almost 200 years ago. Initially thought to be subhuman brutes incapable of anything but the most primitive of grunts, they were a successful form of humanity inhabiting vast swathes of western Eurasia for several hundreds of thousands of years, during harsh ages and milder interglacial periods. We knew that they were our closest cousins, sharing a common ancestor with us around half a million years ago (probably Homo heidelbergensis), but it was unclear what their cognitive capacities were like, or why modern humans succeeded in replacing them after thousands of years of cohabitation. Recently, due to new palaeoanthropological and archaeological discoveries and the reassessment of older data, but especially to the availability of ancient DNA, we have started to realise that their fate was much more intertwined with ours and that, far from being slow brutes, their cognitive capacities and culture were comparable to ours.

Dediu and Levinson review all these strands of literature and argue that essentially modern language and speech are an ancient feature of our lineage dating back at least to the most recent ancestor we shared with the Neanderthals and the Denisovans (another form of humanity known mostly from their genome). Their interpretation of the intrinsically ambiguous and scant evidence goes against the scenario usually assumed by most language scientists, namely that of a sudden and recent emergence of modernity, presumably due to a single – or very few – genetic mutations. This pushes back the origins of modern language by a factor of 10 from the often-cited 50 or so thousand years, to around a million years ago – somewhere between the origins of our genus, Homo, some 1.8 million years ago, and the emergence of Homo heidelbergensis. This reassessment of the evidence goes against a saltationist scenario where a single catastrophic mutation in a single individual would suddenly give rise to language, and suggests that a gradual accumulation of biological and cultural innovations is much more plausible.


Interestingly, given that we know from the archaeological record and recent genetic data that the modern humans spreading out of Africa interacted both genetically and culturally with the Neanderthals and Denisovans, then just as our bodies carry around some of their genes, maybe our languages preserve traces of their languages too. This would mean that at least some of the observed linguistic diversity is due to these ancient encounters, an idea testable by comparing the structural properties of the African and non-African languages, and by detailed computer simulations of language spread.

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