STED microscopy of dendritic and axonal structures in the somatosensory cortex of a mouse, with neurons labeled by enhanced yellow fluorescent protein (credit: Max Planck Institute for Biophysical Chemistry)

Scientists at the Max Planck Institute for Biophysical Chemistry in Göttingen, Germany, have visualized for the first time the finest details of neurons in the brains of a living mouse.

The researchers, led by Stefan Hell, have taken a decisive step towards unraveling the finest structures of the brain to reveal how it works.

Using the Stimulated Emission Depletion (STED) microscopy technique developed by Hell, the scientists have made ​​visible the tiny structures used by neurons to communicate, with unprecedented resolution of less than 70 nanometers. This application of STED microscopy to decipher basic processes in the brain opens new paths to neurobiology studies, such  as dementia and clinical applications.

Neurons have been captured sending and receiving signals in high resolution for the first time, essentially showing the brain in action.

To make the tiniest anatomical details of neurons visible, the researchers used optogenetics to give mice an extra gene that generates a yellow glow. When their brains were viewed with a special microscope through a glass-sealed window in the skull, the synapses in neurons lit up.

See also: First brain movie captures a mouse thinking (New Scientist TV)

Ref.: Sebastian Berning et al., Nanoscopy in a living mouse brain, Science, 2012 [DOI: 10.1126/science.1215369]

The newly discovered "super-Earth" planet is depicted in this artist's conception, showing the host star as part of a triple-star system (credit: Guillem Anglada-Escudé, Carnegie Institution)

An international team of scientists has discovered a potentially habitable super-Earth orbiting a nearby star — the new best candidate to support liquid water and, perhaps, life as we know it, the scientists say.

With an orbital period of about 28 days and a minimum mass 4.5 times that of the Earth, the planet orbits within the star’s “habitable zone,” where temperatures are neither too hot nor too cold for liquid water to exist on the planet’s surface.

The researchers found evidence of at least one and possibly two or three additional planets orbiting the star, which is about 22 light years from Earth.

The team includes UC Santa Cruz astronomers Steven Vogt and Eugenio Rivera and was led by Guillem Anglada-Escudé and Paul Butler of the Carnegie Institution for Science. Their work will be published by Astrophysical Journal Letters.

This diagram shows the orbits of the detected planets around the host star (GJ 667C) in relation to the habitable zone (credit: Guillem Anglada-Escudé, Carnegie Institution)

The host star, called GJ 667C, is a member of a triple-star system (GJ 667AB) and has a different makeup than our sun, with a much lower abundance of elements heavier than helium, such as iron, carbon, and silicon. This discovery indicates that potentially habitable planets can occur in a greater variety of environments than previously believed.

GJ 667C is an M-class dwarf star. The other two stars in the triple-star system are a pair of orange K dwarfs, with a concentration of heavy elements only 25 percent that of our sun’s. Such elements are the building blocks of terrestrial planets, so it was thought to be less likely for metal-depleted star systems to have an abundance of low-mass planets.

“This was expected to be a rather unlikely star to host planets. Yet there they are, around a very nearby, metal-poor example of the most common type of star in our galaxy,” said Vogt, a professor of astronomy and astrophysics at UCSC. “The detection of this planet, this nearby and this soon, implies that our galaxy must be teeming with billions of potentially habitable rocky planets.”

Best candidate to support liquid water and life

The planet (GJ 667Cc) has an orbital period of 28.15 days and a minimum mass of 4.5 times that of Earth. It receives 90 percent of the light that Earth receives. However, because most of its incoming light is in the infrared, a higher percentage of this incoming energy should be absorbed by the planet. When both these effects are taken into account, the planet is expected to absorb about the same amount of energy from its star that the Earth absorbs from the sun.

“This planet is the new best candidate to support liquid water and, perhaps, life as we know it,” Anglada-Escudé said.

The team found that the system might also contain a gas-giant planet and an additional super-Earth with an orbital period of 75 days. However, further observations are needed to confirm these two possibilities.

“With the advent of a new generation of instruments, researchers will be able to survey many M dwarf stars for similar planets and eventually look for spectroscopic signatures of life in one of these worlds,” said Anglada-Escudé, who was with Carnegie when he conducted the research, but has since moved on to the University of Gottingen.

Ref.: Guillem Anglada-Escudé, et al., A planetary system around the nearby M dwarf GJ 667C with at least one super-Earth in its habitable zone, Astrophysical Journal Letters, 2012; [arXiv:1202.0446v1]

super-Earth

iRobot's mobile robotics platform Ava (credit: iRobot)

iRobot Corp. has announced plans to invest $6 million in InTouch Health, a telemedicine company operating in 80 hospitals around the world, possibly building on iRobot’s Ava, a tablet-compatible telepresence robot.

One of NASA's twin Grail spacecraft has returned its first unique picture of the far side of the moon, an image that shows shadowed craters at the moon's south pole. (Credit: NASA/JPL-Caltech)

A gravity-mapping spacecraft orbiting the moon has beamed home its first video of the lunar far side, a view people on Earth never see.

The new video was captured by one of NASA’s twin Grail probes using a novel camera called MoonKAM, which will eventually be used by students on Earth to snap photos of the lunar surface as part of an educational project. The two spacecraft have been circling the moon since they arrived in orbit over the New Year.

Because the moon is tidally locked with Earth, it only presents one face to the planet’s surface (the near side). The side of the moon that faces away from Earth is the far side. Only robotic spacecraft and Apollo astronauts who orbited the moon in the 1960s and 1970s have seen the far side of the moon directly.

(Credit: Sandia National Laboratories )

Sandia National Laboratories researchers have built a prototype of a four-inch-long, small-caliber bullet capable of steering itself towards a laser-marked target located approximately 2,000 meters (1.2 miles) away.

Aided by little fins, the on-board guidance and control electronics use the information passed on by an optical sensor located in the nose to calculate the flight path.

Kissinger Lovotics robot (credit: Hooman Samani)

Artificial intelligence researcher Hooman Samani has invented the “Kissenger,” a small pair of lips stuck to a circular body that you can plug into your computer via a USB cord while you’re Skyping with your partner far across the world.

Simply kiss it and have your partner (human or robotic) do the same. The lips of the Kissenger will mold around yours, thereby simulating the feeling of a real, live human kiss.

Circular polarization (credit: Wikipedia Commons)

Scientists at the Colorado School of Mines (CSM) and ITN Energy Systems have developed a new circular polarization filter with the potential to aid in early cancer detection, enhance vision through dust and clouds, and even improve a moviegoer’s 3D experience.

Polarization is the process by which rays of light exhibit different properties in different directions, but especially the state in which all the vibration or frequency of the light takes place in one visual plane.

When measuring the different properties of light, the human eye can, of course, see in color but it cannot differentiate between the inherently different polarizations of light emanating from an object. This new filter allows users to measure the polarization state of light quickly and efficiently.

Circular micropolarizer

“This is by far the easiest circular micropolarizer to fabricate, which lets us measure all of the properties of light using a simple camera,” notes  ITN researcher Dr. Russell Hollingsworth.

To better understand this new technique, consider the modern digital camera. Color digital cameras are made possible because of the development of micro-color filters that are put directly on the charge-coupled device chip within the camera, where each “pixel” is actually 3 or 4 independent pixels that detect a different discreet color.

The same concept is employed for this new approach to polarization — also using a simple digital camera — but there is also an added benefit. Not only does this new filter distinguish colors, it also measures both linear and circular polarized light.

Photographers are familiar with polarization filters you attach in front of your camera lens to decrease glare. But being able to make micropolarizers right on top of the detector array would result in a “polarization camera” that collects information in the same way color digital cameras do.

While linear polarizer filters are easy to make, circular polarizers, up to this point, have been very difficult to fabricate, but this problem may have been solved. The CSM/ITN research team developed a micro-structure that accurately measures circularly polarized light, the key to making a true polarization camera. On top of that, the new structure can be made to filter for both color and polarization, allowing for a combination color/polarization camera that measures everything about the light.

Super vision

It is those specific light measurements that provide the unique benefits of this new technology. By measuring the polarization state of a light source, you arrive at a number of interesting applications. One significant capability would be to enhance one’s vision through dust/clouds. When light passes through dust or clouds, it typically is polarized in a certain way. A polarization camera can significantly improve the ability to “see through” these obscurants and more accurately determine one’s target, thus both improving target tracking and reducing targeting errors.

Another important application is biological detection based on chirality, wherein an object does not look the same if you rotate it 180 degrees. With certain biological materials, such as DNA, its helix structure can be used to readily image and identify its chirality characteristics to determine “friend or foe.”

Polarized light can also aid in biological detection, identifying tissue anomalies such as cervical cancer. Polarized light, which focuses its energy in one direction, can enable physicians to better see beneath the surface of the cervix for signs of trouble.

The filter development was funded by the U.S. Air Force Office of Scientific Research (AFOSR).

The United States used to be the most educated society in the world. That's no longer true. (Credit: OECD)

Life in this world is not like it used to be just a few decades ago, and the availability of world-class education on-demand, at almost no cost, is likely to help things change all the more as this century unfolds.

YouTube now hosts more than 500,000 educational videos, on a wide variety of topics. The new mobile-friendly iTunes U also offers 500,000 educational resources and says that 60% of its viewership comes from outside the United States. This global consumption of U.S.-created online educational content may be the newest chapter in a radical transformation of global education over the past 50 years.

During the past 50 years, the expansion of education has contributed to a fundamental transformation of societies in Organization for Economic Co-operation and Development (OECD) countries,” wrote the authors of this year’s lengthy report, Education at a Glance 2011: OECD Indicators. (500 page PDF).

Lake Vostok (credit: NASA)

After drilling for two decades through more than two miles of antarctic ice, Russian scientists are on the verge of entering a vast, dark lake that hasn’t been touched by light for more than 20 million years.

This is the first direct contact with what scientists now know is a web of more than 200 subglacial lakes in Antarctica.

Scientists are enormously excited about what life-forms might be found there but are equally worried about contaminating the lake with drilling fluids and bacteria, and the potentially explosive “de-gassing” of a body of water that has especially high concentrations of oxygen and nitrogen.

Age-dependent hypoexcitability of hippocampal CA1 pyramidal neurons (CA1-PCs). Aged mice are shown in gray. (credit: Andrew D. Randall et al./Neurobiology of Aging)

New findings by neuroscientists at the University of Bristol reveal why the brain may become less able to function as we grow older.

In mice studies, the research identified a novel cellular mechanism (sodium channels) underpinning changes to the activity of neurons, which may underlie cognitive decline during normal healthy aging.

The researchers recorded electrical signals in single cells of the hippocampus, a structure with a crucial role in cognitive function to measure “neuronal excitability” — how easy it is to produce brief but very large electrical signals called action potentials (APs).

They found that in the aged brain, it is more difficult to make hippocampal neurons generate action potentials, due to changes to the activation properties of membrane proteins called sodium channels. These mediate the rapid upstroke of the action potential by allowing a flow of sodium ions into neurons.

“Also, by identifying sodium channels as the likely culprit for this reluctance to produce action potentials, our work even points to ways in which we might be able to modify age-related changes to neuronal excitability, and by inference, cognitive ability,” said Professor Randall, University of Bristol Professor in Applied Neurophysiology.

“The mechanism underlying this change in sodium-channel gating properties remains to be explored,” the researchers say.

Ref.: Andrew D. Randall, Clair Booth, Jon T. Brown, Age-related changes to Na+ channel gating contribute to modified intrinsic neuronal excitability, Neurobiology of Aging, 2012; [DOI:10.1016/j.bbr.2011.03.031] (in press)

(Credit: Innovega)

The Defense Advanced Research Projects (DARPA) agency is working with Innovega to create  wearable contact lenses with tiny, full-color displays that digital images can be projected onto to give the wearers better situational awareness in intelligence, surveillance, and reconnaissance (ISR) activities, according to the agency.

iOptiks are contact lenses that enhance normal vision by allowing a wearer to view virtual and augmented reality images without the need for f oversized virtual reality helmets,

Digital images are projected onto tiny full-color displays on the contact lenses. This allows users to focus simultaneously on close-up and far away objects while sill interacting with the surrounding environment.

The high-priority technologies include items such as radiation mitigation; guidance, navigation, and control; nuclear systems for both power generation and transportation; and solar power generation.

These priorities were chosen to align with three main facets of NASA’s overall mission: extending and sustaining human activities beyond low Earth orbit; exploring the evolution of the solar system and the potential for life elsewhere; and expanding our understanding of Earth and the universe.

The following table identifies recommended highest-priority technologies for NASA research and development over the next five years:

A great magnetic bubble surrounds the solar system as it cruises through the galaxy. The sun pumps the inside of the bubble full of solar particles that stream out to the edge until they collide with the material that fills the rest of the galaxy, at a complex boundary called the heliosheath. On the other side of the boundary, electrically charged particles from the galactic wind blow by, but rebound off the heliosheath, never to enter the solar system. Neutral particles, on the other hand, are a different story. They saunter across the boundary as if it weren't there, continuing on another 7.5 billion miles for 30 years until they get caught by the sun's gravity, and sling shot around the star. There, NASA's Interstellar Boundary Explorer lies in wait for them ... (Credit: NASA)

NASA’s Interstellar Boundary Explorer (IBEX) has captured the best and most complete glimpse yet of what lies beyond the solar system.

The new measurements give clues about how and where our solar system formed, the forces that physically shape our solar system, and the history of other stars in the Milky Way.

The Earth-orbiting spacecraft observed four separate types of atoms including hydrogen, oxygen, neon and helium. These interstellar atoms are the byproducts of older stars, which spread across the galaxy and fill the vast space between stars.

IBEX determined the distribution of these elements outside the solar system, which are flowing charged and neutral particles that blow through the galaxy, or the so-called interstellar wind.

In a series of science papers appearing in the Astrophysics Journal on Jan. 31, scientists report finding 74 oxygen atoms for every 20 neon atoms in the interstellar wind. In our own solar system, there are 111 oxygen atoms for every 20 neon atoms. This translates to more oxygen in any part of the solar system than in nearby interstellar space.

NASA's Interstellar Boundary Explorer (IBEX) studies the outer boundaries of the solar system, where particles from the solar wind collide with particles from the galactic wind (credit: NASA)

“Our solar system is different than the space right outside it, suggesting two possibilities,” says David McComas, IBEX principal investigator, at the Southwest Research Institute in San Antonio.

“Either the solar system evolved in a separate, more oxygen-rich part of the galaxy than where we currently reside, or a great deal of critical, life-giving oxygen lies trapped in interstellar dust grains or ices, unable to move freely throughout space.”

The new results hold clues about the history of material in the universe. While the big bang initially created hydrogen and helium, only the supernovae explosions at the end of a star’s life can spread the heavier elements of oxygen and neon through the galaxy. Knowing the amounts of elements in space may help scientists map how our galaxy evolved and changed over time.

Exploring the interstellar medium

Scientists want to understand the composition of the boundary region that separates the nearest reaches of our galaxy, called the local interstellar medium, from our heliosphere. The heliosphere acts as a protective bubble that shields our solar system from most of the dangerous galactic cosmic radiation that otherwise would enter the solar system from interstellar space.

IBEX measured the interstellar wind traveling at a slower speed than previously measured by the Ulysses spacecraft, and from a different direction. The improved measurements from IBEX show a 20 percent difference in how much pressure the interstellar wind exerts on our heliosphere.

“Measuring the pressure on our heliosphere from the material in the galaxy and from the magnetic fields out there will help determine the size and shape of our solar system as it travels through the galaxy,” says Eric Christian, IBEX mission scientist, at NASA’s Goddard Space Flight Center in Greenbelt, Md.

The IBEX spacecraft was launched in October 2008. Its science objective is to discover the nature of the interactions between the solar wind and the interstellar medium at the edge of our solar system.

The galactic wind streams toward the sun from the direction of Scorpio and IBEX has found that it travels at 52,000 miles an hour. The speed of the galactic wind and its subsequent pressure on the outside of the solar system's boundary affects the shape of the heliosphere as it travels through space (credit: NASA/Goddard Scientific Visualization Studio)

The Southwest Research Institute developed and leads the IBEX mission with a team of national and international partners.

The spacecraft is one of NASA’s series of low-cost, rapidly developed missions in the Small Explorers Program. Goddard manages the program for the agency’s Science Mission Directorate at NASA Headquarters in Washington.

Among the six U.S. institutions on the IBEX mission are the University of New Hampshire (UNH), the LMATC, SwRI, the University of Texas, San Antonio, MIT, and the University of Chicago.

See also:

February issue of The Astrophysical Journal Supplement Series (written by IBEX team members)
IBEX: Glimpses of the Interstellar Material Beyond our Solar System (NASA)
IBEX Team, UNH Scientist Present Mission Findings Today at NASA Press Conference (UNH)

A survey of entrepreneurs found that most started their first company at age 39. People with degrees in computer science started companies much sooner than those with advanced training in other sciences or engineering. (Credit: Kauffman Foundation)

Research by Vivek Wadhwa, VP of academics and innovation at Singularity University, and his team found in a survey that the average and median age of the founders of successful U.S. technology businesses (with real revenues) is 39.

They found twice as many successful founders over 50 as under 25, and twice as many over 60 as under 20.

However, “understanding diverse technologies isn’t the domain of the young,” Wadhwa says.

“Though college dropouts may know all about social media, it is very unlikely that they understand the intricacies of nanotechnology and artificial intelligence as well as their elders do. These are complex technologies that require not only a strong education but also the ability to work across domains and collaborate with intellectual peers in different disciplines of science and engineering.”

Neural precursor cells (upper left) differentiate into oligodendrocytes, astrocytes, and neurons (credit: Ernesto Lujana et al./PNAS)

Mouse skin cells can be converted directly into cells that become the three main parts of the nervous system, according to researchers at the Stanford University School of Medicine.

The finding is an extension of a previous study by the same group showing that mouse and human skin cells can be directly converted into functional neurons.

Neural precursor cells

This new study transforms the skin cells into neural precursor cells, as opposed to just neurons. They can also become the two other main cell types in the nervous system: astrocytes and oligodendrocytes.

Neural precursor cells offer another advantage over neurons:they can be cultivated to large numbers in the laboratory — a feature critical for their long-term usefulness in transplantation or drug screening. The finding implies that it may one day be possible to generate a variety of neural-system cells for transplantation that would perfectly match a human patient.

“We’ve shown the cells can integrate into a mouse brain and produce a missing protein important for the conduction of electrical signal by the neurons,” said Marius Wernig, MD, assistant professor of pathology and a member of Stanford’s Institute for Stem Cell Biology and Regenerative Medicine. “This is important because the mouse model we used mimics that of a human genetic brain disease. However, more work needs to be done to generate similar cells from human skin cells and assess their safety and efficacy.”

Bypassing induced pluripotency and embryonic stem cells

The multiple successes of the direct conversion method could refute the idea that pluripotency (a term that describes the ability of stem cells to become nearly any cell in the body) is necessary for a cell to transform from one cell type to another. Together, the results raise the possibility that embryonic stem cell research and another technique called “induced pluripotency” could be supplanted by a more direct way of generating specific types of cells for therapy or research.

Scientists had thought that it was necessary for a cell to first enter an induced pluripotent state or for researchers to start with an embryonic stem cell, which is pluripotent by nature, before it could go on to become a new cell type. However, research from Wernig’s laboratory in early 2010 showed that it was possible to directly convert one “adult” cell type to another with the application of specialized transcription factors, a process known as transdifferentiation.

“Dr. Wernig’s demonstration that fibroblasts can be converted into functional nerve cells opens the door to consider new ways to regenerate damaged neurons using cells surrounding the area of injury,” said pediatric cardiologist Deepak Srivastava, MD, who was not involved in these studies.

“It also suggests that we may be able to transdifferentiate cells into other cell types.” Srivastava is the director of cardiovascular research at the Gladstone Institutes at the University of California-San Francisco. In 2010, Srivastava transdifferentiated mouse heart fibroblasts into beating heart muscle cells.

“Direct conversion [from skin] has a number of advantages,” said Graduate student Ernesto Lujan, the first author. “It occurs with relatively high efficiency and it generates a fairly homogenous population of cells. In contrast, cells derived from iPS cells must be carefully screened to eliminate any remaining pluripotent cells or cells that can differentiate into different lineages.” Pluripotent cells can also cause cancers when transplanted into animals or humans, according to the scientists.

Human transplantation experiments

The scientists are now working to replicate the work with skin cells from adult mice and humans, but Lujan emphasized that much more research is needed before any human transplantation experiments could be conducted. In the meantime, however, the ability to quickly and efficiently generate neural precursor cells that can be grown in the laboratory to mass quantities and maintained over time will be valuable in disease and drug-targeting studies.

“In addition to direct therapeutic application, these cells may be very useful to study human diseases in a laboratory dish or even following transplantation into a developing rodent brain,” said Wernig.

Ref.: E. Lujan, et al., Direct conversion of mouse fibroblasts to self-renewing, tripotent neural precursor cells, Proceedings of the National Academy of Sciences, 2012; [DOI:10.1073/pnas.1121003109]

Our devices allow us to compress time and space in a way that we’re able to mentally transport ourselves between planes of existence with the touch of a button. (Or, rather, a digital rendering of a button.)

This is the dilemma of being a cyborg: it’s that we’re collectively engaged in a mass conversion of what we used to call, variously, records, accounts, entries, archives, registers, collections, keepsakes, catalogs, testimonies and memories into, simply, data.

We’ve outsourced our memories to external devices, said science journalist Joshua Foer. “The result is that we no longer trust our memories. We see every small, forgotten thing as evidence that they’re failing us altogether.” As we store more and more of what makes us us outside of ourselves, “we’ve forgotten how to remember.”

(Credit: James Duncan Davidson/TED)

TED will host auditions in 14 countries on six continents this spring, reports the Mashable blog. Anybody can submit an application on the TED website, and include a short video if they’d like, but auditions are invite-only.

Favorites from live auditions will record short videos to post on TED.com for public voting, and the top 50 most popular contenders will be considered for TED 2013 programming.

TED’s website says the organization is looking for “undiscovered talent,” perhaps “the inventor,” “the teacher,” “the prodigy” or “the artist.” It is not looking for “product-hawkers, jargon-junkies, dullards, wafflers, motivator wannabes, self-promoters, spouters of new-age fluff.”

An X-ray CT scan of the head of one of the volunteers, showing electrodes distributed over the brain’s temporal lobe, where sounds are processed. (Credit: Adeen Flinker, UC Berkeley)

Neuroscientists may one day be able to hear the imagined speech of a patient unable to speak due to stroke or paralysis, according to University of California, Berkeley researchers.

These scientists have succeeded in decoding electrical activity in the brain’s temporal lobe — the seat of the auditory system — as a person listens to normal conversation. Based on this correlation between sound and brain activity, they then were able to predict the words the person had heard solely from the temporal lobe activity.

Audio file for original and reconstructed words

“This is huge for patients who have damage to their speech mechanisms because of a stroke or Lou Gehrig’s disease and can’t speak,” said co-author Robert Knight, a UC Berkeley professor of psychology and neuroscience. “If you could eventually reconstruct imagined conversations from brain activity, thousands of people could benefit.”

“This research is based on sounds a person actually hears, but to use it for reconstructing imagined conversations, these principles would have to apply to someone’s internal verbalizations,” cautioned first author Brian N. Pasley, a post-doctoral researcher in the center.

“There is some evidence that hearing the sound and imagining the sound activate similar areas of the brain. If you can understand the relationship well enough between the brain recordings and sound, you could either synthesize the actual sound a person is thinking, or just write out the words with a type of interface device.”

Subjects listened to words (acoustic waveform, top left) while neural signals were recorded from cortical surface electrode arrays (top right, red circles) implanted over superior and middle temporal gyrus (STG, MTG). Speech-induced cortical field potentials (bottom right, gray curves) recorded at multiple electrode sites were used to fit multi-input, multi-output models for offline decoding. The models take as input time-varying neural signals at multiple electrodes and output a spectrogram consisting of time-varying spectral power across a range of acoustic frequencies (180-7000 Hz, bottom left). To assess decoding accuracy, the reconstructed spectrogram is compared to the spectrogram of the original acoustic waveform. (Credit: Brian N. Pasley)

In addition to the potential for expanding the communication ability of the severely disabled, he noted, the research also “is telling us a lot about how the brain in normal people represents and processes speech sounds.”

They enlisted the help of people undergoing brain surgery to determine the location of intractable seizures so that the area can be removed in a second surgery. Neurosurgeons typically cut a hole in the skull and safely place electrodes on the brain surface or cortex — in this case, up to 256 electrodes covering the temporal lobe — to record activity over a period of a week to pinpoint the seizures. For this study, 15 neurosurgical patients volunteered to participate.

Pasley visited each person in the hospital to record the brain activity detected by the electrodes as they heard 5 to 10 minutes of conversation. Pasley used this data to reconstruct and play back the sounds the patients heard. He was able to do this because there is evidence that the brain breaks down sound into its component acoustic frequencies — for example, between a low of about 1 Hz (cycles per second) to a high of about 8,000 Hz — that are important for speech sounds.

.

Spectrograms of the original and reconstructed words. For audio playback, the spectrogram or modulation representations must be converted to an acoustic waveform, a transformation that requires both magnitude and phase information. Because the reconstructed representations are magnitude-only, the phase must be estimated. (Credit: Brian N. Pasley)

Audio file for original and reconstructed words

Pasley tested two different computational models to match spoken sounds to the pattern of activity in the electrodes. The patients then heard a single word, and Pasley used the models to predict the word based on electrode recordings.

“We are looking at which cortical sites are increasing activity at particular acoustic frequencies, and from that, we map back to the sound,” Pasley said. He compared the technique to a pianist who knows the sounds of the keys so well that she can look at the keys another pianist is playing in a sound-proof room and “hear” the music, much as Ludwig van Beethoven was able to “hear” his compositions despite being deaf.

The better of the two methods was able to reproduce a sound close enough to the original word for Pasley and his fellow researchers to correctly guess the word.

“We think we would be more accurate with an hour of listening and recording and then repeating the word many times,” Pasley said. But because any realistic device would need to accurately identify words heard the first time, he decided to test the models using only a single trial.

“This research is a major step toward understanding what features of speech are represented in the human brain” Knight said. “Brian’s analysis can reproduce the sound the patient heard, and you can actually recognize the word, although not at a perfect level.”

Knight predicts that this success can be extended to imagined, internal verbalizations, because scientific studies have shown that when people are asked to imagine speaking a word, similar brain regions are activated as when the person actually utters the word.

“With neuroprosthetics, people have shown that it’s possible to control movement with brain activity,” Knight said. “But that work, while not easy, is relatively simple compared to reconstructing language. This experiment takes that earlier work to a whole new level.”

The current research builds on work by other researchers about how animals encode sounds in the brain’s auditory cortex. In fact, some researchers, including the study’s coauthors at the University of Maryland, have been able to guess the words ferrets were read by scientists based on recordings from the brain, even though the ferrets were unable to understand the words.

The ultimate goal of the UC Berkeley study was to explore how the human brain encodes speech and determine which aspects of speech are most important for understanding.

“At some point, the brain has to extract away all that auditory information and just map it onto a word, since we can understand speech and words regardless of how they sound,” Pasley said. “The big question is, What is the most meaningful unit of speech? A syllable, a phone, a phoneme? We can test these hypotheses using the data we get from these recordings.”

Chang and Knight are members of the Center for Neural Engineering and Prostheses, a joint UC Berkeley/UCSF group focused on using brain activity to develop neural prostheses for motor and speech disorders in disabling neurological disorders.

Ref.: Brian N. Pasley et al., Reconstructing speech from human auditory cortex, PLoS Biology, Jan. 31, 2012 [link]

Experimental phase change memory chip (credit: Samsung)

Researchers at IBM and elsewhere are exploring the idea that phase change materials (PCMs) could hold more information by switching between an amorphous state and a crystalline one.

PCM memory can write and retrieve data 100 times faster than Flash memory, which is used in many consumer gadgets and computers. It is also extremely durable and can be reused at least 10 million times; Flash can cope with just 3000 uses.

But PCM memory’s true potential lies in its ability to store more than a single bit per cell. “If you are able to control the current you can create states between the two, something that is not fully crystallized and something that is not fully amorphous,” says Evangelos Eleftheriou, head of storage technologies at IBM’s Zurich Research Laboratory in Switzerland.

Precisely how many states can be created remains to be seen, but some researchers, like David Wright at the University of Exeter in the UK, have already demonstrated 512 discrete states in a single 20-nanometre cell — about the same size as a Flash memory cell, which usually only holds two.

A cylindrical tube was cloaked with a shell of plasmonic metamaterial to make it appear invisible (credit: Andrea Alu/University of Texas at Austin)

Researchers led by the University of Texas at Austin have cloaked a three-dimensional object standing in free space, bringing the invisibility cloak one step closer to reality.

The researchers used “plasmonic metamaterials” to hide an 18-centimeter cylindrical tube from microwaves.

When light strikes an ordinary object, it rebounds off its surface towards another direction, just like throwing a tennis ball against a wall. The reason we see objects is because light rays bounce off materials towards our eyes and our eyes are able to process the information.

Plasmonic metamaterials have the opposite scattering effect.  “When the scattered fields from the cloak and the object interfere, they cancel each other out and the overall effect is transparency and invisibility at all angles of observation.

“One of the advantages of the plasmonic cloaking technique is its robustness and moderately broad bandwidth of operation, superior to conventional cloaks based on transformation metamaterials. This made our experiment more robust to possible imperfections, which is particularly important when cloaking a 3D object in free-space,” said study co-author Professor Andrea Alu.

Near-field mapping of the electric field distribution (snapshot in time) around and on top of the object under test (credit: Andrea Alu/University of Texas at Austin)

In this instance, the cylindrical tube was cloaked with a shell of plasmonic metamaterial to make it appear invisible. The cloak worked best at a frequency of 3.1 gigahertz with a moderately broad bandwidth.

“In principle, this technique could be used to cloak light; in fact, some plasmonic materials are naturally available at optical frequencies,” said Alu. “However, the size of the objects that can be efficiently cloaked with this method scales with the wavelength of operation, so when applied to optical frequencies we may be able to efficiently stop the scattering of micrometer-sized objects.

“Still, cloaking small objects may be exciting for a variety of applications. For instance, we are currently investigating the application of these concepts to cloak a microscope tip at optical frequencies. This may greatly benefit biomedical and optical near-field measurements,” continued Professor Alu.

Ref.: D Rainwater, et al., Experimental verification of three-dimensional plasmonic cloaking in free-space, New Journal of Physics, 2012; 14 (1): 013054 [DOI: 10.1088/1367-2630/14/1/013054]

(Credit: Faculty of 1000)

The Faculty of 1000 (F1000) has announced an experiment in online science publishing aimed at sharing research results widely and rapidly, Nature News Blog reports.

Unlike ArXiv, it will use open peer review to check postings afterwards and will charge for submissions.

The F1000 Research project begins publishing later this year, covering biology and medicine. It will accept any format of work (posters, data tables, discursive speculation based on preliminary results, raw data sets and protocols, for example) after an “initial sanity check.”

It encourages authors to keep revising and updating what they have published. And by default, it will use open publishing licenses, allowing others to share and remix posted research (with attribution).

Also see: An arXiv for all of science?

DARPA plans to announce a new program to develop power technologies that could bolster computer system performance per watt from today’s 1 GFLOPS/watt to 75 GFLOPS/watt.

The goal of the program, called Power Efficiency Revolution For Embedded Computing Technologies or PERFECT, is to take a revolutionary approach to processing/power efficiency of embedded systems, and excludes exascale processing issues.

GPS tracker (credit: PI Gear)

Anyone with $300 can buy a GPS tracking device no bigger than a cigarette pack, attach it to a car without the driver’s knowledge, and watch the vehicle’s travels and stops — at home on your laptop. Uses include monitoring teenage children, Alzheimer’s patients, and spouses.

However, the Supreme Court held on Jan 23 that under the Fourth Amendment of the Constitution, by placing a GPS tracker on a vehicle, a police officer is doing a search. Use of GPS trackers are illegal in California and Texas, and increasingly being cited in cases of criminal stalking and civil violations of privacy.

The objective: take an entirely new look at aging. Some interesting excerpts:

Jay Olshansky

The goal of research in this area in my view is not to extend life. The goal is to extend healthy life. If we live longer, I consider that a bonus. However, I would encourage you to be asking the same question of those now working to combat heart disease, cancer, and stroke, and those who experience these conditions. Why we we all want to live longer? I believe what we are talking about here are interventions that enable us to live our lives healthy for as long as possible.

There have been some reductions in death rates at older ages as you know, but these are for more difficult to achieve than reductions in death rates at younger ages that occurred in the past. I see no reason why life expectancy at age 85 cannot increase — it’s just that the gains in life expectancy must be small because the overall risk of death that these later ages is extremely high. The longer we live, the harder it is to generate increases in life expectancy — especially at older ages.

Aubrey de Grey

We age simply because the human body is a machine, and it accumulates damage as a normal side-effect of its operation, just as simple man-made machines do. We live longer than most mammals because we have more comprehensive in-built repair and maintenance machinery than they do.

So in a sense, yes, there is a proven way to delay aging: we know that we will do that if we develop medicine that sufficiently comprehensively repairs the damage of aging, just as we can keep cars or houses in good condition well beyond their “warranty period” by that same method. What we don’t yet have, of course, is actual implementation of that repair medicine — but we’re getting there.

Aubrey de Grey: None of my colleagues ever provides actual scientific reasons for disputing my claim that regenerative medicine is likely, even while still quite imperfect; to deliver “longevity escape velocity” leading to indefinite longevity; they just don’t like to admit it. Well, I prefer to tell the truth, even if it may be politically uncomfortable; I’m sure that in the long run it will hasten these therapies’ development.

The K computer (credit: RIKEN)

The next generation of powerful supercomputers will be used to design high-efficiency engines tailored to burn biofuels, reveal the causes of supernova explosions, track the atomic workings of catalysts in real time, and study how persistent radiation damage might affect the metal casing surrounding nuclear weapons.

Those uses require supercomputers more powerful than any yet designed: These “exascale” computers would be capable of carrying out 10¹⁸ floating point operations per second, or an exaflop. That’s nearly 100 times more powerful than today’s biggest supercomputer, Japan’s “K computer,” which achieves 11.3 petaflops (10¹⁵ flops).

Power

The largest supercomputers today use about 10 megawatts (MW) of power, enough to power 10,000 homes. If the current trend of power use continues, an exascale supercomputer would require 200 MW, which would take a nuclear power reactor to run it. Solutions: energy-efficient graphical processing units (GPUs), which are very fast at certain types of calculations; and “many-core” chips, each containing potentially hundreds of CPU and GPU cores, allowing them to assign different calculations to specialized processors.

Memory

Chip storage density cannot economically keep up with the performance gains of processors. Potential solutions: 3D chips and stack memory chips atop processors to minimize the distance bits need to travel.

Errors

Modern processors compute with stunning accuracy, but they aren’t perfect. The average processor will produce one error per year, as a thermal fluctuation or a random electrical spike flips a bit of data from one value to another. No good solutions are in the works.

Software applications

DOE is funding three “co-design” centers, multi-institution cooperatives led by researchers at Los Alamos, Argonne, and Sandia national laboratories. The centers bring together scientific users who write the software code and hardware makers to design complex software and computer architectures that work in the fastest and most energy-efficient manner.

Money

DOE officials estimated that creating an exascale computer would cost $3 billion to $4 billion over 10 years. That amount would pay for one exascale computer for classified defense work, one for nonclassified work, and two 100-petaflops machines to work out some of the technology along the way. Funding has not yet been approved.

Implanted transponder scavenging musical sound and radiating an RF pulse at the resonant frequency of the passive sensor (credit: Birck Nanotechnology Center, Purdue University)

A driving bass rhythm can be harnessed to power a new type of miniature medical sensor designed to be implanted in the body.

Low-frequency acoustic waves from music were found to effectively recharge the pressure sensor. Such a device might ultimately help to treat people stricken with aneurisms or incontinence due to paralysis.

The heart of the sensor is a vibrating cantilever, a thin beam attached at one end like a miniature diving board. Music within a certain range of frequencies, 200–500 hertz, causes the cantilever to vibrate, generating electricity and storing a charge in a capacitor, said Babak Ziaie, a Purdue University professor of electrical and computer engineering and biomedical engineering.

“The music reaches the correct frequency only at certain times, for example, when there is a strong bass component,” he said. “The acoustic energy from the music can pass through body tissue, causing the cantilever to vibrate.”

Inductive pressure sensor with acoustic scavenging (credit: Birck Nanotechnology Center, Purdue University)

When the frequency falls outside of the proper range, the cantilever stops vibrating, automatically sending the electrical charge to the sensor, which takes a pressure reading and transmits data as radio signals.

Because the frequency is continually changing according to the rhythm of a musical composition, the sensor can be induced to repeatedly alternate intervals of storing charge and transmitting data.

“You would only need to do this for a couple of minutes every hour or so to monitor either blood pressure or pressure of urine in the bladder,” Ziaie said. “It doesn’t take long to do the measurement.”

The microelectromechanical system (MEMS) device was created in the Birck Nanotechnology Center at the university’s Discovery Park. The cantilever beam is made from a ceramic material called lead zirconate titanate (PZT), which is piezoelectric, meaning it generates electricity when compressed. The sensor is about 2 centimeters long. Researchers tested the device in a water-filled balloon.

Proposed electromechanical scavenging/interrogation circuit (credit: Birck Nanotechnology Center, Purdue University)

A receiver that picks up the data from the sensor could be placed several inches from the patient. Playing tones within a certain frequency range also can be used instead of music.

“But a plain tone is a very annoying sound,” Ziaie said. “We thought it would be novel and also more aesthetically pleasing to use music.”

Researchers experimented with four types of music: rap, blues, jazz and rock.

“Rap is the best because it contains a lot of low frequency sound, notably the bass,” Ziaie said.

The sensor is capable of monitoring pressure in the urinary bladder and in the sack of a blood vessel damaged by an aneurism. Such a technology could be used in a system for treating incontinence in people with paralysis by checking bladder pressure and stimulating the spinal cord to close the sphincter that controls urine flow from the bladder. It could also be used to diagnose incontinence. The conventional diagnostic method now is to insert a probe with a catheter, which must be in place for several hours while the patient remains at the hospital.

A miniature pressure sensor designed to be implanted in the body. Acoustic waves from music or plain tones drive a vibrating device called a cantilever, generating a charge to power the sensor. (Credit: Birck Nanotechnology Center, Purdue University)

“A wireless implantable device could be inserted and left in place, allowing the patient to go home while the pressure is monitored,” Ziaie said.

The new technology offers potential benefits over conventional implantable devices, which either use batteries or receive power through inductance, which uses coils on the device and an external transmitter.

Both approaches have downsides. Batteries have to be replaced periodically, and data are difficult to retrieve from devices that use inductance; coils on the implanted device and an external receiver must be lined up precisely, and they can only be about a centimeter apart.

Ref.: A. Kim, T. Maleki, and B. Ziaie, A Novel Electromechanical Interrogation Scheme for Implantable Passive Transponders, findings are detailed in a paper to be presented during the IEEE MEMS conference, Jan. 29 to Feb. 2 in Paris

The Allen Telescope Array (credit: SETI Institute)

Early in December, 42 radio telescopes, the Allen Telescope Array, in Hat Creek, California went back into operation.

The astronomers say that another $55 million would complete the planned array of 350 antennas, but there have been no volunteers yet.

The U.S. Air Force, interested in tracking satellites and space junk,
will pay for a share of the annual operations at Hat Creek, which costs about $1.5 million (plus another $1 million a year to pay the astronomers). But the money raised so far will buy a few months at best.

Constellation (credit: Nick Payne/Royal Court Theater)

In Nick Payne’s new play, Constellations, universe-crossing lovers repeat a scene over and over with different outcomes in different parallel universes, New Scientist Culture Lab reports.

MQ-9 Reaper drone (credit: U.S. Air Force)

Security researcher Brendan O’Connor is building a sensor-equipped surveillance-capable computer that’s so cheap it can be dropped from a drone and sacrificed after one use, with off-the-shelf parts that anyone can buy and assemble for less than $50.

The F-BOMB (Falling or Ballistically launched Object that Makes Backdoors), built from just the hardware in a commercially available $25 PogoPlug mini-computer, a few tiny antennas, 8GB of flash memory, and some 3D-printed plastic casing, the F-BOMB serves as 3.5x4x1 inch spy computer.

It can be plugged inconspicuously into a wall socket, thrown over a barrier, or otherwise put into irretrievable positions to quietly collect data and send it back to the owner over any available Wi-Fi network.

The c-Cbl protein changes shape when switched on, marking a cell for destruction to prevent uncontrolled cell growth leading to cancer (credit: Hao Dou, et al./Nature Structural & Molecular Biology)

Cancer Research UK scientists have mapped the first 3D structure of c-Cbl, a key protein that protects against the development of cancer.

The team at Cancer Research UK’s Beatson Institute for Cancer Research, in Glasgow used X-ray analysis to map the structure of a protein called c-Cbl and showed that it changes shape when it is switched on.

c-Cbl controls cell growth , which when unregulated causes cells to divide excessively and can lead to cancer. The protein is defective in some leukemia patients. Discovering that c-Cbl can switch between two shapes may help scientists find ways to prevent faulty c-Cbl from triggering cancer.

“Understanding the structure of this protein is vital, because if the protein can’t be switched on, it is more likely to cause cancer,” said lead author, Dr. Danny Huang, at Cancer Research UK’s Beatson Institute in Glasgow. “So cracking the 3D structure is a step towards designing the cancer drugs of the future.”

The team showed that when it’s switched on, c-Cbl labels a cell receptor molecule for destruction. By labeling the receptor molecule for destruction, the cell growth signal is switched off at the right time. If c-Cbl cannot change to its active shape, it cannot label the receptor for destruction.

In healthy cells, the receptor amplifies a chain of cell signals, resulting in normal cell growth. But in cancer cells, these signals do not get switched off, leading to uncontrolled cell growth.

Ref.: Hao Dou, et al., Structural basis for autoinhibition and phosphorylation-dependent activation of c-Cbl, Nature Structural & Molecular Biology, 2012; [DOI:10.1038/nsmb.2231]

After five days of mitosis and CAMo, polarized breast cells have assembled into an acinar sphere with a lumen in the center (inset) (credit: Berkeley Lab)

In a study that holds major implications for breast cancer research and basic cell biology, scientists with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered a rotational motion that plays a critical role in the ability of breast cells to form the spherical structures in the mammary gland known as acini.

This rotation, which the researchers call “CAMo,” for coherent angular motion, is necessary for the cells to form spheres. Without CAMo, the cells do not form spheres, which can lead to random motion, loss of structure and malignancy.

”What is most exciting to me about this stunning discovery is that it may finally give us a handle by which to discover the physical laws of cellular motion as they apply to biology,” says Mina Bissell, a leading authority on breast cancer and Distinguished Scientist with Berkeley Lab’s Life Sciences Division.

Healthy human epithelial cells in breast and other glandular tissue form either sphere-shaped acini or tube-shaped ducts. The cell and tissue polarity (function-enabling spatial orientations of cellular and tissue structures) that comes with the formation of acini is essential for the health and well-being of the breast. Loss of this polarity as a result of cells not forming spheres is one of the earliest signs of malignancy.

However, despite all that is known about cell morphogenesis, the fundamental question as to how epithelial cells are able to assemble into spheres that are similar in size and shape to organs in vivo has until now been a mystery.“We’ve discovered a novel type of cell motility where single cells undergo multiple rotations and cohesively maintain that rotational motion as they divide and assemble into acini,” says Tanner. “We’ve also demonstrated that this CAMo is a critical function for the establishment of spherical architecture and not simply a consequence of multicellular aggregates. If CAMo is disrupted, the final geometry is not a sphere.”

Bissell and colleagues found that CAMo arises from a centripetal force generated by the flexing of crescent-shaped muscle-like molecules called actomyosin in the cell’s cytoskeleton. This centripetal force sets the cell to rotating about an axis. The rotation is slow, barely once an hour, it may run clockwise or counterclockwise, and its axis might shift, but this rotational motion is cohesive. It continues as the cell divides and the subsequent progeny form into acini, bestowing on cells and acini the polarity and the cavity needed for proper form and function.

“Without CAMo, the cells lose their way and do not form structures that allow mammary cells to make and secrete milk,” says Tanner. “In order to form a polarized sphere, the cells have to be properly oriented so that certain components are up and certain components are down. The CAMo rotation provides the cells with this orientation.”

Bissell is renowned for her pioneering work that elucidated the critical role in breast cancer development played by the extracellular matrix (ECM), a network of fibrous and globular proteins in the microenvironment that surrounds a breast cell. Her experiments have shown that when the nucleus of a breast cell fails to receive the proper biochemical cues and signals from the ECM and other components of the microenvironment, cells and tissue lose structure, which opens the door to malignancy. The discovery of CAMo now provides an important missing mechanism that facilitates the reception and response of a breast cell to the cues and signals from the ECM.

“In this study, we found that malignant cells do not display CAMo but instead become randomly motile and do not form spheres.”In recent research, Bissell and her group demonstrated that through manipulation of the ECM, malignant cells cultured in an ECM enriched with laminin — a protein that they had shown induces cell quiescence — can undergo a reversion in which their normal phenotype is restored despite their malignant genome.

In this new study, Tanner, Bissell and their colleagues found that when malignant cells cultured in the 3D ECM surrogate gel underwent phenotypic reversion in response to signaling inhibitors, CAMo was restored. When CAMo was restored, the reverted cancer cells formed polarized spheres.

“These results complement our early hypothesis that signaling and support by the ECM when cells are in proper context informs both form and function in cells,” Bissell says. “The results also suggest that in response to microenvironmental cues from the ECM, cells execute a program of cytoskeletal movements that dictate different kinds of motilities. We hypothesize that these motilities direct the formation of a given type of tissue and preclude other multicellular geometries. We believe this is a crucial evolutionary phenomena for multicellular organisms.”

“Once the cells are sufficiently adhered to one another, they can continue CAMo as a cohesive unit,” Tanner says. “We postulate that this cohesive CAMo motility is the mechanism by which the original structure of the breast tissue is restored following lactation and breast feeding.”

The next step for the research team will be to study the effects of CAMo from the perspective of the ECM.

“We would like to look at the interaction of the ECM with a single cell as it undergoes CAMo and show the in vivo relevance,” Tanner says.

Ref.: Kandice Tanner, et al., Coherent angular motion in the establishment of multicellular architecture of glandular tissues, Proceedings of the National Academy of Sciences, 2012; [DOI: 10.1073/pnas.1119578109] (open access)

Domed lunar settlement (credit: Pat Rawlings/NASA)

Newt Gingrich has called for a bold, aggressive space program that would establish a permanent base on the Moon by 2020, along with a next-generation propulsion system for taking humans to Mars, and commercial near-Earth activities that include science, tourism, and manufacturing.

Transcript of the speech, courtesy of the National Space Society.

This could mean high-speed wireless connections for the county’s residents, and also the potential to connect to Wi-Fi towers that are miles distant (not possible with conventional Wi-Fi).

However, high-power Super Wi-Fi signals (up to four watts), which can travel for miles, must give TV channels a wide berth. Low-power Super Wi-Fi signals (less than 40 milliwatts) face fewer restrictions. So while there are 48 channels potentially available for long-range Super Wi-Fi, zero or one channel will be available for long-range use in the places most Americans live. More info.

A powerful X-ray laser pulse from SLAC National Accelerator Laboratory's Linac Coherent Light Source comes up from the lower-left corner (green) and hits a neon atom (center), which emit more X-rays, creating a domino effect that amplifies the laser light 200 million times. (Credit: Gregory M. Stewart/SLACj/Nature)

Lawrence Livermore Lab (LLNL) scientists and international collaborators have created the shortest, purest X-ray laser pulses ever achieved, fulfilling a 45-year-old prediction and ultimately opening the door to new medicines, devices and materials.

The researchers aimed radiation from the Linac Coherent Light Source (LCLS), located at the Stanford Linear Accelerator Center (SLAC), at a cell containingneon gas, setting off an avalanche of femtosecond-duration
X-ray emissions to create a new “atomic X-ray laser” in the kiloelectronvolt energy regime.

“X-rays give us a penetrating view into the world of atoms and molecules,” said physicist Nina Rohringer, a former LLNL postdoc, now a group leader at Max Planck Society’s Advanced Study Group. She collaborated with researchers from SLAC, LLNL and Colorado State University.

The new laser fulfills a 1967 prediction, which proposed that X-ray lasers could be made by first removing inner electrons from atoms and then inducing electrons to fall from higher to lower energy levels, releasing a single color of light in the process. But until 2009, when LCLS turned on, no X-ray sources were powerful enough to create this type of laser.

To make the atomic X-ray laser, LCLS’s powerful X-ray pulses — each a billion times brighter than any available before — knocked electrons out of the inner shells of many of the neon atoms. When other electrons fell in to fill the holes, about one in 50 atoms responded by emitting a “hard X-ray,” which has a very short wavelength (1.46 nanometers). Those X-rays then stimulated neighboring neon atoms to emit more X-rays, creating a domino effect that amplified the laser light 200 million times.

It may be useful for high-resolution spectroscopy and nonlinear X-ray studies.

In the future, Rohringer says she will try to create even shorter-pulse, higher-energy atomic X-ray lasers using oxygen, nitrogen or sulfur gases.

Ref.: Nina Rohringer, et al., Atomic inner-shell X-ray laser at 1.46 nanometres pumped by an X-ray free-electron laser, Nature, 2012; 481 (7382): 488 [DOI:10.1038/nature10721]

Potassium atom (credit: Rice University)

Rice University physicists have gone to extremes to prove that Isaac Newton’s classical laws of motion can apply in the atomic world: They’ve built an accurate model of part of the solar system inside a single atom of potassium.

They showed they could cause an electron in an atom to orbit the nucleus in precisely the same way that Jupiter’s Trojan asteroids orbit the sun.

The findings uphold a prediction made in 1920 by famed Danish physicist Niels Bohr about the relationship between the then-new science of quantum mechanics and Newton’s tried-and-true laws of motion.

“Bohr predicted that quantum mechanical descriptions of the physical world would, for systems of sufficient size, match the classical descriptions provided by Newtonian mechanics,” said lead researcher Barry Dunning, Rice’s Sam and Helen Worden Professor of Physics and chair of the Department of Physics and Astronomy. “Bohr also described the conditions under which this correspondence could be observed. In particular, he said it should be seen in atoms with very high principal quantum numbers, which are exactly what we study in our laboratory.”

In the new experiments, Rice graduate students Brendan Wyker and Shuzhen Ye began by using an ultraviolet laser to create a Rydberg atom. Rydberg atoms contain a highly excited electron with a very large quantum number. In the Rice experiments, potassium atoms with quantum numbers between 300 and 600 were studied.

“In such excited states, the potassium atoms become hundreds of thousands of times larger than normal and approach the size of a period at the end of a sentence,” Dunning said. “Thus, they are good candidates to test Bohr’s prediction.”

He said comparing the classical and quantum descriptions of the electron orbits is complicated, in part because electrons exist as both particles and waves. To “locate” an electron, physicists calculate the likelihood of finding the electron at different locations at a given time. These predictions are combined to create a “wave function” that describes all the places where the electron might be found. Normally, an electron’s wave function looks like a diffuse cloud that surrounds the atomic nucleus, because the electron might be found on any side of the nucleus at a given time.

Dunning and co-workers previously used a tailored sequence of electric field pulses to collapse the wave function of an electron in a Rydberg atom; this limited where it might be found to a localized, comma-shaped area called a “wave packet.” This localized wave packet orbited the nucleus of the atom much like a planet orbits the sun. But the effect lasted only for a brief period.

“We wanted to see if we could develop a way to use radio frequency waves to capture this localized electron and make it orbit the nucleus indefinitely without spreading out,” Ye said.

They succeeded by applying a radio frequency field that rotated around the nucleus itself. This field ensnared the localized electron and forced it to rotate in lockstep around the nucleus.

A further electric field pulse was used to measure the final result by taking a snapshot of the wave packet and destroying the delicate Rydberg atom in the process. After the experiment had been run tens of thousands of times, all the snapshots were combined to show that Bohr’s prediction was correct: The classical and quantum descriptions of the orbiting electron wave packets matched. In fact, the classical description of the wave packet trapped by the rotating field parallels the classical physics that explains the behavior of Jupiter’s Trojan asteroids.

Jupiter’s 4,000-plus Trojan asteroids — so called because each is named for a hero of the Trojan wars — have the same orbit as Jupiter and are contained in comma-shaped clouds that look remarkably similar to the localized wave packets created in the Rice experiments. And just as the wave packet in the atom is trapped by the combined electric field from the nucleus and the rotating wave, the Trojans are trapped by the combined gravitational field of the sun and orbiting Jupiter.

The researchers are now working on their next experiment: They’re attempting to localize two electrons and have them orbit the nucleus like two planets in different orbits.

“The level of control that we’re able to achieve in these atoms would have been unthinkable just a few years ago and has potential applications in, for example, quantum computing and in controlling chemical reactions using ultrafast lasers,” Dunning said.

Ref.: B. Wyker, et al., Creating and Transporting Trojan Wave Packets, Physical Review Letters, 2012; [DOI:10.1103/PhysRevLett.108.043001]

Experimental limits against confinement energy (credit: Michael Sarrazin et al.)

Our universe may exist in parallel with other universes in other sets of dimensions, or braneworlds, so things from our Universe might somehow end up in another, some cosmologists suggest, says Technology Review Physics arXiv Blog.

Michael Sarrazin at the University of Namur in Belgium and a few others showed how matter might make the leap in the presence of large magnetic potentials. That provided a theoretical basis for real matter swapping.

Today, Sarrazin and associates say that our galaxy might produce a magnetic potential large enough to make this happen for real. If so, we ought to be able to observe matter leaping back and forth between universes in the lab. In fact, such observations might already have been made in certain experiments.

The experiments in question involve trapping ultracold neutrons in bottles at places like the Institut Laue Langevin in Grenoble, France, and the Saint Petersburg Institute of Nuclear Physics.

Ref.: Michael Sarrazin et al., Experimental Limits On Neutron Disappearance Into Another Braneworld, arxiv.org/abs/1201.3949

The first ever co-operative space game made for the Hayden Planetarium Dome of the Museum of Natural History (credit: Ivan Safrin and Babycastles)

The Hayden Planetarium, under Neil DeGrasse Tyson’s direction, is becoming Space Cruiser, a giant virtual spacecraft videogame on a 4500×4500 pixel screen, Motherboard blog reports.

Together, players will collaborate to navigate a virtual ship through asteroid belts and other dangers — kind of like a massively-multiplayer version of Carl Sagan’s imaginary space vessel from Cosmos.

It will also have oher space-related indie games: Osmos, a surreal space simulator; Kerbal Space Program, a build-your-own spaceship game; and Bit Pilot, a shooter by Zach Gage.

It premieres for one night only this Thursday at the Museum of Natural History in New York. Tickets (use code BEYOND for half off) at the museum’s website.

Mobility-on-Demand systems consisting of lightweight electric vehicles designed by the MIT Media Lab's Smart Cities research group (credit: MIT)

A full-scale version of the stackable, electric CityCar, created by researchers at the MIT Media Lab and commercialized by a consortium of automotive suppliers in the Basque region of Spain, was unveiled at the European Union Commission headquarters on January 24.

Branded “Hiriko,” the two-passenger EV vehicle incorporates all of the essential concepts of the MIT Media Lab CityCar: a folding chassis to occupy a small footprint when parked, drive-by-wire control, front entry and egress, the ability to spin on its axis, and “Robot Wheels” with integrated electric drive motor, steering motor, suspension, and braking. It is capable of folding to minimize its parking footprint.

Since 2009, the Media Lab has collaborated with Denokinn, an industrial sponsor from Vitoria, Spain, and their partner companies to refine the design and technology of the CityCar to allow for its commercialization by industry. The CityCar project is part of larger initiative at the MIT Media Lab devoted to investigating the urban mobility systems.

Robot Wheels

The CityCar compared to traditional automobiles (credit: MIT)

The design utilizes a novel technology called Robot Wheels. The Robot Wheel modules are controlled electronically using by-wire systems made popular by the aerospace industry and is attached to the four corners of the foldable chassis designed by the MIT team.

Each Robot Wheel can be independently controlled, allowing the CityCar to execute tight maneuvers that are helpful when driving in cities such as spinning on its own axis to achieve an “O-turn.” T

The removal of traditional drivetrain elements like gasoline engine, transmissions, and gearboxes allows for an unencumbered chassis thus freeing up space for folding linkages.

When folded, three CityCars can fit into one traditional parking space, therefore making parking more efficient in dense crowded cities. The CityCar has a range of over 100km on one charge and is capable of being rapidly charged using the latest lithium-ion battery technologies developed by industry including spinout companies from MIT.

Professor Mitchell’s Smart Cities research group at the MIT Media Lab (2003-2010) designed the CityCar to take on the biggest issues facing cities today–that of congestion, inefficient energy and land-use, air and noise pollution, and carbon emissions leading to global warming.

Mobility-on-Demand

The team also created a new model of mobility that would utilize the CityCar and other lightweight EVs in a shared-use scheme. By deploying CityCars at charging points distributed throughout a metropolitan area the MIT team envisioned a new network of vehicles that would allow any user of the system to simply walk-up, swipe an access card, pick-up a vehicle, and drive to any other charging point.

Called Mobility-on-Demand, this strategy would provide high levels of convenience and flexibility found in shared systems like bike sharing programs, available in much of Europe and now in North America.

Mobility-on-Demand systems also addresses what transportation planners call the “First Mile, Last Mile” problem of mass transit systems, by providing mobility near or at a user’s origin and final destination by creating a intermodal network that is complementary and synergistic to transit systems.

In addition to the CityCar, the Smart Cities team also designed a folding electric motor scooter called the RoboScooter, and an electric assist bicycle called the GreenWheel. The GreenWheel integrates Lithium-ion batteries with electric motors into a modular hub unit that could easily be retrofitted into any standard bicycle.

Together with the CityCar, the RoboScooter and GreenWheel would create a Mobility-on-Demand ecosystem of lightweight and low-energy EVs, where users can select the appropriate vehicle for each trip segment.

The research on urban mobility conducted by the Smart Cities group resulted in the publication of the book Reinventing the Automobile: Personal Urban Mobility for the 21st Century, published by MIT Press. Professor Mitchell wrote this book along with two top research executives from General Motors (Chris Borroni-Bird and Lawrence Burns).

CityHome

A related project called the CityHome examines the potential of highly personalized, responsive housing with transformable interiors so that small apartments function as if far larger. The combination of the CityHome and CityCar project are building blocks to a larger ecosystem approach towards making new cities more livable and sustainable.

Researchers of the Changing Places Group are continuing to develop new vehicles, including a 3-wheel “persuasive electric vehicle,” with the goal of expanding the demographic profile of bike-lane users, as well as encouraging exercise and highly efficient mobility.

In addition, the group is currently exploring how new concepts for urban housing, mobility-on-demand, and energy systems can be applied to cities in China, as well as smaller communities in the area devastated by 2011 tsunami in the Miyagi Prefecture of Japan.

Nanotube (Rice University)

Nanomaterials have moved into the marketplace over the last decade, in products as varied as cosmetics, clothing and paint. But not enough is known about their potential health and environmental risks, which should be studied further, an expert panel of the National Academy of Sciences said on Wednesday.

And because the nanotechnology market is expanding — it represented $225 billion in product sales in 2009 and is expected to grow rapidly in the next decade — “today’s exposure scenarios may not resemble those of the future,” the report says.

The panel called for a four-part research effort focusing on identifying sources of nanomaterial releases, processes that affect exposure and hazards, nanomaterial interactions at subcellular to ecosystem-wide levels and ways to accelerate research progress.

The last time the academy weighed in on this was in a report in 2008 that included a sweeping critique of the National Nanotechnology Initiative, the federal body that coordinates nano-related activities across agencies. In its report on Wednesday, the academy acknowledged the initiative’s progress, but added that “there has not been sufficient linkage between research and research findings and the creation of strategies to prevent and manage risk.”

Self driving car (credit: Google)

Questions of legal liability, privacy and insurance regulation self-driving vehicles have yet to be addressed, and such challenges might pose far more problems than the technological ones.

Should the police have the right to pull over autonomous vehicles?

Human drivers frequently bend the rules by rolling through stop signs and driving above speed limits; how would a polite and law-abiding robot vehicle fare against such competition?

What about potential liabilities, which will be huge for the designers and manufacturers of autonomous vehicles?

Will there be unpredictable technological risks? For example, future autonomous vehicles will rely heavily on global positioning satellite data and other systems, which are vulnerable to jamming by malicious computer hackers.

And some trivial tasks for human drivers — like recognizing an officer or safety worker motioning a driver to proceed in an alternate direction — await a breakthrough in artificial intelligence that may not come soon.

“Eventually, people will get better care from AI,” says medical AI programmer Fred Trotter. “For now, we should keep the algorithms focused on the data that we know is good and keep the doctors focused on the patients. We should be worried about making patient data accurate and reliable.”

Consumers who are logged into Google services won’t be able to opt out of the changes, which take effect March 1. And experts say the policy shift will invite greater scrutiny from federal regulators of the company’s privacy and competitive practices.

A user signing up for Gmail, for instance, might never have imagined that the content of his or her messages could affect the experience on seemingly unrelated Web sites such as YouTube.

Consumers could also benefit, the company said. When someone is searching for the word “jaguar,” Google would have a better idea of whether the person was interested in the animal or the car. Or the firm might suggest e-mailing contacts in New York when it learns you are planning a trip there.

A 3D-printed object. (credit: Carter West Engineering, Inc.)

The notion that 3D printing will on any reasonable time scale become a “mature” technology that can reproduce all the goods on which we rely is to engage in a complete denial of the complexities of modern manufacturing, unless you’d like everything made out of plastic, says Technology Review | Mim’s Bits blog.

3-D images from a single particle: (A) a series of images of an ApoA-1 protein particle, taken from different angles. A succession of four computer enhancements (projections) clarifies the signal. In the right column is the 3-D image compiled from the clarified data. (B) is a close-up of the reconstructed 3-D image. (C) Analysis shows how the particle structure is formed by three ApoA-1 proteins (red, green, blue noodle-like models). (Credit: Berkeley Lab)

Lawrence Berkeley National Laboratory (Berkeley Lab) scientists have created detailed models of a single protein using electron microscopic images.

Scientists routinely create models of proteins using X-ray diffraction, nuclear magnetic resonance, and conventional cryo-electron microscope (cryoEM) imaging. But these models require computer “averaging” of data from analysis of thousands, or even millions of like molecules, because it is so difficult to resolve the features of a single particle.

Gang Ren calls his technique “individual-particle electron tomography,” or IPET.

The 3-D images include those of a single IgG antibody and apolipoprotein A-1 (ApoA-1), a protein involved in human metabolism. Ren’s goal is to produce individual 3-D images of medically significant proteins, such as HDL,  the heart-protective “good cholesterol” whose structure has eluded the efforts of legions of scientists, armed with far more powerful protein modeling tools.

His images of single proteins are a bit fuzzy, even after they are cleaned up by complex computer filtering, but very informative to the trained observer. These individual particles are extraordinarily tiny, requiring Ren to zero in on a spot of less than 20 nanometers. He has reported protein images as small as 70 kDa. That’s kilodaltons, a Lilliputian scale (expressed in units of mass) set aside for taking the measure of atoms, molecules, and snippets of DNA. It’s a more useful way to size soft objects like proteins that can be clumped, stringy, or floppy.

Within the complex structure of these proteins lies the secrets of their function, and perhaps keys to drugs that block the bad ones and promote the good ones. With some additional computer filtering, a high-contrast model of protein can be generated from the images and animated to show its moving parts in 3-D.

By observing the structure of single proteins, it is possible to understand their flexible, moving parts. “This opens a door for the study of protein dynamics,” Ren says. “Antibodies, for example, are not solid. They are very flexible, very dynamic.”

How did Ren coax so much versatility out of his Libra 120? He’s equipped the microscope with a $300,000 CCD camera, some powerful image-processing software, special contrasting agents, and a device called an “energy filter” that sifts through the digitized camera data and culls weak signals. The multiple angles used to create the 3-D portrait help resolve the faint molecular image.

Electron microscopes focus streams of electrons rather than light to see incredibly tiny things. The short wavelength of an electron beam enables much higher resolution and magnification than visible light. Powerful electron microscopes have been used for decades to probe materials at atomic-scale; and right next door to the Molecular Foundry is Berkeley Lab’s National Center for Electron Microscopy, which houses the most powerful microscopes in the world. The TEAM 0.5 microscope can distinguish objects as small as the radius of a hydrogen atom. But these heavyweight microscopes pull off this atomic-scale resolution with pulses of energy that would obliterate most soft biological proteins. The high power electron microscopes are used primarily for probing atomic structure of strong, solid materials, such as graphene.

Ren’s lab specializes in cryoEM, which examines objects frozen at -180 °C (-292 °F). A bath of liquid nitrogen flash-freezes samples so quickly that no ice crystals form. The extremely low temperature fixes the samples and prevents them from drying out in the vacuum needed for the electron scan. It creates conditions favorable for imaging at much lower doses of electrons — low enough to keep a single soft protein intact while more than 100 images are taken over a one-to-two hour period.

Ref.: Lei Zhang and Gang Ren, IPET and FETR: Experimental Approach for Studying Molecular Structure Dynamics by Cryo-Electron Tomography of a Single-Molecule Structure, PLoS ONE, 2012; [DOI:10.1371/journal.pone.0030249]

A computer animation demonstrates the flexible dynamics — the moving parts — of human IgG antibody. 3-D images of two individual antibody particles (gray) were generated using EM tomography with IPET. The demonstration shows how the same molecular chains (red, orange, and green noodle-like models) of antibody particle #1 can fit precisely into particle #2, which was found under the microscope in an entirely different pose.

Self-assembly of a synthetic phospholipid membrane by adding copper ions to an emulsion of an oil and a detergent, forming vesicles and tubules (credit: Itay Budin and Neal K. Devaraj/ACS)

Chemists have taken an important step in making artificial life forms from scratch, creating self-assembling cell membranes, the structural envelopes that contain and support the reactions required for life and make a living organism from non-living molecules.

Although Dr. Craig Venter recently announced the creation of the “first synthetic living cell,” only its genome was artificial. The rest was a hijacked bacterial cell. Fully artificial life will require the union of both an information-carrying genome and a three-dimensional structure to house it.

Molecules that make up cell membranes have heads that mix easily with water and tails that repel it. In water, they form a double layer with heads out and tails in, a barrier that sequesters the contents of the cell. The chemists created similar molecules with a novel reaction that joins two chains of lipids. Nature uses complex enzymes that are themselves embedded in membranes to accomplish this, making it hard to understand how the very first membranes came to be.

Complex cell membrane showing phospholipid membrane (credit: NIST)

“In our system, we use a sort of primitive catalyst, a very simple metal ion,” said Neal Devaraj, assistant professor of chemistry at the University of California, San Diego. “The reaction itself is completely artificial. There’s no biological equivalent of this chemical reaction. This is how you could have a de novo formation of membranes.”

They created the synthetic membranes from a watery emulsion of an oil and a detergent. Alone it’s stable. Add copper ions and sturdy vesicles and tubules begin to bud off the oil droplets. After 24 hours, the oil droplets are gone, “consumed” by the self-assembling membranes.

The real value of this discovery might reside in its simplicity. From commercially available precursors, the scientists needed just one preparatory step to create each starting lipid chain. “It’s trivial and can be done in a day,” said Devaraj. “New people who join the lab can make membranes from day one.”

By assembling an essential component of earthly life with no biological precursors, they hope to illuminate life’s origins.

Ref.: Itay Budin and Neal K. Devaraj, Membrane Assembly Driven by a Biomimetic Coupling Reaction, Journal of the American Chemical Society, 2012; [DOI: 10.1021/ja2076873]

Linac Coherent Light Source SXR experimental chamber. The central part of the frame contains the holder for the material that will be converted by the powerful LCLS laser into hot, dense matter. To the left is an XUV spectrometer and to the right is a small red laser set up for alignment and positioning. (Credit: University of Oxford/Sam Vinko)

SLAC National Accelerator Laboratory researchers have used the world’s most powerful X-ray laser to create and probe a 2-million-degree piece of matter in a controlled way for the first time.

This feat takes scientists a significant step forward in understanding the most extreme matter found in the hearts of stars and giant planets, and could help experiments aimed at recreating the nuclear fusion process that powers the sun.

SLAC’s Linac Coherent Light Source (LCLS) rapid-fire laser pulses are a billion times brighter than those of any X-ray source before it. Scientists used those pulses to flash-heat a tiny piece of aluminum foil less than a trillionth of a second, creating what is known as “hot dense matter,” at a temperature of about 2 million degrees Celsius.

“Making extremely hot, dense matter is important scientifically if we are ultimately to understand the conditions that exist inside stars and at the center of giant planets within our own solar system and beyond,” said Sam Vinko, a postdoctoral researcher at Oxford University and the paper’s lead author.

Scientists have long been able to create plasma from gases and study it with conventional lasers, said co-author Bob Nagler of SLAC, an LCLS instrument scientist. But no tools were available for doing the same at solid densities that cannot be penetrated by conventional laser beams.

The measurements will feed back into theories and computer simulations of how hot, dense matter behaves and could help scientists analyze and recreate the nuclear fusion process that powers the sun.

Ref.: S. M. Vinko, et al., Creation and diagnosis of a solid-density plasma with an X-ray free-electron laser, Nature, 2012; [DOI:10.1038/nature10746]

Instead of getting meat from animals raised in pastures, he wants to grow steaks in lab conditions, directly from muscle stem cells. If successful, the technology will transform the way we produce food. “We want to turn meat production from a farming process to a factory process,” he explained.

Prof. Post is using cells called myosatellites, a form of muscle stem cell that is normally used by the body to repair damaged muscle. Myosatellite cells can be extracted from a mature animal without killing it and have numerous advantages.

Cultured meat — also known as in vitro meat or lab-grown meat — draws on the science of stem cell technology used in medicine. Stem cells are extracted from a pig, say, and converted to pig muscle cells. These muscle cells are then cultured on a scaffold with nutrients and essential vitamins and grown to desired quantities.

The Pirate Bay

The Pirate Bay, one of the world’s most infamous online piracy and file-sharing sites, is now hosting a type of mock-up file that allows your 3D printer to create physical objects.

Users can now search in a new category called “Physibles,” mock-up files that allow a 3D printer to create a physical object:

“We believe that the next step in copying will be made from digital form into physical form,” The Pirate Bay blog said yesterday. “We believe that in the nearby future, you will print your spare parts for your vehicles.”

Magic Mushroom (Psilocybe semilanceata) (credit: Ralpharama/Wikimedia Commons)

Former U.K. government drugs adviser Prof. David Nutt of Imperial College London has said that “overwhelming” regulations should be relaxed to enable researchers to experiment on mind-altering drugs.

Nutt told BBC News that magic mushrooms, LSD, ecstasy, cannabis, and mephedrone all have potential therapeutic applications, but were not being studied because of the restrictions placed on researching illegal drugs.

Nutt was fired by the home secretary from his government advisory role three years ago for saying that ecstasy and LSD were less harmful than alcohol.

He says his new research indicated that there were no “untoward effects” from taking magic mushrooms and that it should not be illegal to possess them.

He said the harm from illegal drugs could be equal to
harm in other parts of life, such as horse-riding, hence his invented term “equasy” or “equine addiction syndrome.”

See also:
news | “This is your brain on magic mushrooms”
news | “Fed-funded research: magic mushrooms create ‘openness’”