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TRAP-1 knock-out mice show signs of longer lives with fewer age-related diseases

TRAP-1 knock-out mice show signs of longer lives with fewer age-related diseases | Amazing Science | Scoop.it

While developing a new cancer drug, researchers at The Wistar Institute discovered that mice lacking a specific protein live longer lives with fewer age-related illnesses. The mice, which lack the TRAP-1 protein, demonstrated less age-related tissue degeneration, obesity, and spontaneous tumor formation when compared with normal mice. Their findings could change how scientists view the metabolic networks within cells.


In healthy cells, TRAP-1 is an important regulator of metabolism and has been shown to regulate energy production in mitochondria, organelles that generate chemically useful energy for the cell. In the mitochondria of cancer cells, TRAP-1 is universally overproduced.  


The Wistar team’s report, which appears in the journal Cell Reports (available online now), shows how “knockout” mice bred to lack the TRAP-1 protein compensate for this loss by switching to alternative cellular mechanisms for making energy.


“We see this astounding change in TRAP-1 knockout mice, where they show fewer signs of aging and are less likely to develop cancers,” said Dario C. Altieri. M.D., Robert and Penny Fox Distinguished Professor and director of The Wistar Institute’s National Cancer Institute-designated Cancer Center. “Our findings provide an unexpected explanation for how TRAP-1 and related proteins regulate metabolism within our cells.”


“We usually link the reprogramming of metabolic pathways with human diseases, such as cancer,” Altieri said. “What we didn’t expect to see were healthier mice with fewer tumors.”


Altieri and his colleagues created the TRAP-1 knockout mice as part of their ongoing investigation into their novel drug, Gamitrinib, which targets the protein in the mitochondria of tumor cells. TRAP-1 is a member of the heat shock protein 90 (HSP90) family, which are “chaperone” proteins that guide the physical formation of other proteins and serve a regulatory function within mitochondria. Tumors use HSP90 proteins, like TRAP-1, to help survive therapeutic attack. 

“In tumors, the loss of TRAP-1 is devastating, triggering a host of catastrophic defects, including metabolic problems that ultimately result in the death of the tumor cells,” Altieri said.  “Mice that lack TRAP-1 from the start, however, have three weeks in the womb to compensate for the loss of the protein.”


The researchers found that in their knockout mice, the loss of TRAP-1 causes mitochondrial proteins to misfold, which then triggers a compensatory response that causes cells to consume more oxygen and metabolize more sugar. This causes mitochondria in knockout mice to produce deregulated levels of ATP, the chemical used as an energy source to power all the everyday molecular reactions that allow a cell to function.

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Fossils could be discovered on the moon: Signs of ancient life may be littered across the moon

Fossils could be discovered on the moon: Signs of ancient life may be littered across the moon | Amazing Science | Scoop.it
Physicists have tested what would happen if a piece of rock containing microscopic fossils from Earth was launched into space and hit the surface of the moon. The team turned fossil-filled rock into powder which was mixed with water and frozen to replicate a meteoroid.


Kent physicists have tested what would happen if a piece of rock containing microscopic fossils from Earth was launched into space and hit the surface of the moon.


In order to do this, Professor Mark Burchell and researchers from the University's Centre for Astrophysics simulated the condition that fossilised diatoms -- microscopic algae with detailed shells -- might have faced if travelling from earth to the moon.


The team turned fossil-filled rock into powder which was mixed with water and frozen to replicate a meteoroid. The replica meteoroid was then fired into a bag of water using a large gas-powered gun to allow it experience the impact of being launched into orbit, whilst the rapid deceleration and high pressure as it hit the water simulated how it might have smashed into the moon at high speed.


This suggests that if earth meteorites are ever found on the moon -- in the same way that we find lunar meteorites on earth -- then they may contain fossils from Earth's past.


Reference:

  1. M. J. Burchell, K. H. McDermott, M. C. Price, L. J. Yolland. Survival of fossils under extreme shocks induced by hypervelocity impactsPhilosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2014; 372 (2023): 20130190 DOI: 10.1098/rsta.2013.0190
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Keep, Delete, Modify: Synthetic Genes, Synthetic Cells, Synthetic Life

Keep, Delete, Modify: Synthetic Genes, Synthetic Cells, Synthetic Life | Amazing Science | Scoop.it
Nature needed about one billion years to create the simplest single-cell organisms that swam around in the primordial soup. Now, scientists are eager to create synthetic life – but better and faster.


Hamilton Smith (Nobel Prize in Chemistry 1978 with Werner Arber and Daniel Nathans) started his lecture at the 64th Nobel Laureate Meeting in Lindau with a quote from Richard Feynman (Nobel Prize in Physics 1965): Feynman had probably meant physical models, whereas Smith referred to living organisms. In his laboratory at the J. Craig Venter Institute, he tries to create synthetic cells: “I hope that if we create that, we will understand.”


Nowadays, the entire human genome has been decoded. But how a live human being develops from DNA molecules, a human being that can breath, eat, walk, study, love, receive Nobel Prizes and award them – nobody really understands yet. Even for single-cell organisms, this isn’t crystal clear. Even the simplest bacteria exhibit genes without apparent function, that are not essential for life. During evolution, a lot of ‘genetic waste’ has accumulated that might have been useful at some point, but was rendered useless by mutations. Some genetic fragments were in fact smuggled into the genome by viruses, others were created by accidental duplications of genetic segments. Numerous molecular mechanisms lead to many genetic variations – rendering evolution possible in the first place. But over time, many of these genes and segments have become useless.


Currently Smith tries to tidy up the genome of Mycoplasma mycoides, a microbe normally living in the digestive tract of ruminants. Originally Smith and his team wanted to use the genome of Mycoplasma genitalium, the bacterium with the smallest known genome – it needs only 475 genes to live. Smith estimates that about 100 of these are non-essential. But since M. mycoides has a much higher cell division rate, although its genome is twice as large, experiments with M. mycoides proved to be more effective. During this ‘minimal cell project’, the researchers switch off one gene after another and study the effects on the microbes. (And the slower the microbes grow, the longer the researchers have to wait for their results.) Smith’s final goal is “a genome that is very understandable – we are searching for the genetic kernels of life”.


Smith also assumes that all genes from the last group can be switched off without negative impacts on the microbes. Concerning the middle category, the researchers have to carefully weigh all options. When all is done, the result should be a bacterium that can still multiply rapidly, at least in laboratory conditions that offer plenty of nourishment, constant temperatures, but no competitors. The researchers’ goal is a fifty percent genome reduction in a happily thriving microbe that divides at least once in 100 minutes.


Smith likes using computer terms to describe his work. He compares the genome of any organism with its software, the rest is hardware (the cytoplasm, proteins and enzymes), controlled by said software. As soon as a cell receives a new genetic program, it starts to put this program to use. In order to test their own synthetic programs, Smith and his team replaced the bacterium’s DNA with synthetic DNA containing their basic program. To date, the old ‘hardware’ has not adopted the new program ‘update’. In computer speak, troubleshooting and maintenance are called “debugging”: Smith and his team will be busy with debugging for some time.

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SourceForge.net Introduces the PyCX Project for Scientific Visualization based on Python

SourceForge.net Introduces the PyCX Project for Scientific Visualization based on Python | Amazing Science | Scoop.it

PyCX is an online repository of simple, crude, easy-to-understand sample codes for various complex systems simulation, including iterative maps, cellular automata, dynamical networks and agent-based models. All the sample codes were written in plain Python, a general-purpose programming language widely used in industry as well as in academia, so that students can gain practical skills for both complex systems simulation and computer programming simultaneously. The core philosophy of PyCX is on the simplicity, readability, generalizability and pedagogical values of simulation codes. PyCX has been used in instructions of complex systems modeling at several places with successful outcomes.


Until nearly the end of the last century, dynamic simulations of complex systems—such as cellular automata and agent-based models—were only available to researchers who had sufficient technical skills to develop and operate their own simulation software. At that time, there were very few general-purpose simulation software packages available (e.g., (Hiebeler 1994; Wuensche 1994)), and those packages were rather hard to program, unless one had a computer science background. The lack of general-purpose simulation software easily accessible for non-computer scientists was a major limiting factor for the growth of complex systems science, given the highly interdisciplinary nature of the field.


Over the last decade, several easy-to-use complex systems modeling and simulation software packages have been developed and become widely used for scientific research, including NetLogo (2004), Repast (2003), Mason (2004) (for agent-based models) and Golly (2005) (for cellular automata). They have been playing a critical role in making complex systems modeling and simulation available to researchers outside computer science. A number of publications used these software packages as key research tools, and increasingly many online tutorials and sample simulation models are becoming publicly available.


However, such existing software has several problems when used for teaching complex systems modeling and simulation in higher education settings. These are all real issues we have faced in classrooms and other educational settings over the last several years. Firstly, and most importantly for college students, learning languages or libraries specific to particular simulation software used only in academia would not help the students advance their general technical skills. Because most students will eventually build their careers outside complex systems science, they usually want to learn something generalizable and marketable, even though they want to study complex systems science and they do appreciate its concepts and values.


Secondly, even for those who actively work on complex systems research, choices of preferred software vary greatly from discipline to discipline, and therefore it is quite difficult to come up with a single commonly agreeable choice of software useful for everyone. This is particularly problematic when one has to teach a diverse group of students, which is not uncommon in complex systems education.


Thirdly, details of model assumptions and implementations in pre-built simulation software are often hidden from the user, such as algorithms of collision detection, time allocation and state updating schemes. As we all know, such microscopic details can and do influence macroscopic behavior of the model, especially in complex systems simulations.


Finally, using existing simulation software necessarily puts unrecognized limitations to the user’s creativity in complex systems research, because the model assumptions and analytical methods are influenced significantly by what is available in the provided software. This is a fundamental issue that could hamper the advance of complex systems science, since any breakthroughs will be achieved only by creating entirely novel ways of modeling and/or analyzing complex systems that were not done before.


These issues in using existing simulation software for complex systems education leads to the following very challenging riddle: Which computational tool is best for teaching complex systems modeling and simulation, offering students generalizable, marketable skills, being accessible and useful for everyone across disciplines, maintaining transparency in details, and imposing no implicit limit to the modeling and analysis capabilities?


Obviously, there would be no single best answer to this kind of question. In what follows, we present a case of our humble attempt to give our own answer to it, hoping that some readers may find it helpful for solving their unique challenges in complex systems education.


Through several years of experience in complex systems education, people have come to realize that using a simple general-purpose computer programming language itself as a complex systems modeling platform is our current best solution to address most, if not all, of the educational challenges discussed above. By definition, general-purpose computer programming languages are universal and can offer unlimited opportunity of modeling with all the details clearly spelled out in front of the user’s eyes. Identifying a programming language that would be easily accessible and useful in a wide variety of disciplines had been difficult even a decade ago. Fortunately, several easy-to-use programming languages have recently emerged and become very popular in various scientific and industrial communities, including Python and R.


Using the Python language itself as a modeling and simulation platform, “PyCX” has been developed, an online repository of simple, crude, easy-to-understand sample codes for various complex systems simulation. The target audiences of PyCX are researchers, scientists, and students who are interested in developing their own complex systems simulation software using a general-purpose programming language but do not have much experience in computer programming. Based on carefully designed sample codes, the audience can understand, modify, create and visualize dynamic complex systems simulations relatively easily.


The core philosophy of PyCX is therefore placed on the simplicity, readability, generalizability and pedagogical values of simulation codes. This is often achieved even at the cost of computational speed, efficiency or maintainability. For example: (1) every PyCX sample code is written as a single.py file, which is a plain text file, without being split into multiple separate files; (2) all the dynamic simulations follow the same scheme consisting of three parts (initialization, visualization and updating); (3) no object-oriented programming paradigm is used because it is sometimes difficult for non-computer scientists to grasp; and (4) no global variables are used to make the code more intuitive and readable. These choices were intentionally made based on our experience in teaching complex systems modeling and simulation to non-computer scientists and their feedback.


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Self-assembling anti-cancer molecules created in minutes

Self-assembling anti-cancer molecules created in minutes | Amazing Science | Scoop.it

Small cationic amphiphilic α-helical peptides are emerging as agents for the treatment of cancer and infection, but they are costly and display unfavorable pharmacokinetics. Helical coordination complexes may offer a three-dimensional scaffold for the synthesis of mimetic architectures. However, the high symmetry and modest functionality of current systems offer little scope to tailor the structure to interact with specific biomolecular targets, or to create libraries for phenotypic screens.


Scientists now report the highly stereoselective asymmetric self-assembly of very stable, functionalized metallohelices. Their anti-parallel head-to-head-to-tail ‘triplex’ strand arrangement creates an amphipathic functional topology akin to that of the active sub-units of, for example, host-defence peptides and p53. The metallohelices display high, structure-dependent toxicity to the human colon carcinoma cell-line HCT116 p53++, causing dramatic changes in the cell cycle without DNA damage. They have lower toxicity to human breast adenocarcinoma cells (MDA-MB-468) and, most remarkably, they show no significant toxicity to the bacteria methicillin-resistant Staphylococcus aureus and Escherichia coli.

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Implanted Neurons made from Skin Cells become Part of the Brain

Implanted Neurons made from Skin Cells become Part of the Brain | Amazing Science | Scoop.it

Scientists at the Luxembourg Centre for Systems Biomedicine (LCSB) of the University of Luxembourg have grafted neurons reprogrammed from skin cells into the brains of mice for the first time with long-term stability. Six months after implantation, the neurons had become fully functionally integrated into the brain. This successful, because lastingly stable, implantation of neurons raises hope for future therapies that will replace sick neurons with healthy ones in the brains of Parkinson’s disease patients, for example. The Luxembourg researchers published their results in the current issue of ‘Stem Cell Reports’.


The LCSB research group around Prof. Dr. Jens Schwamborn and Kathrin Hemmer is working continuously to bring cell replacement therapy to maturity as a treatment for neurodegenerative diseases. Sick and dead neurons in the brain can be replaced with new cells. This could one day cure disorders such as Parkinson’s disease. The path towards successful therapy in humans, however, is long. “Successes in human therapy are still a long way off, but I am sure successful cell replacement therapies will exist in future. Our research results have taken us a step further in this direction,” declares stem cell researcher Prof. Schwamborn, who heads a group of 15 scientists at LCSB.


In their latest tests, the research group and colleagues from the Max Planck Institute and the University Hospital Münster and the University of Bielefeld succeeded in creating stable nerve tissue in the brain from neurons that had been reprogrammed from skin cells. The stem cell researchers’ technique of producing neurons, or more specifically induced neuronal stem cells (iNSC), in a petri dish from the host’s own skin cells considerably improves the compatibility of the implanted cells. The treated mice showed no adverse side effects even six months after implantation into the hippocampus and cortex regions of the brain. In fact it was quite the opposite – the implanted neurons were fully integrated into the complex network of the brain. The neurons exhibited normal activity and were connected to the original brain cells via newly formed synapses, the contact points between nerve cells.


Reference:

Hemmer K., Zhang M., van Wüllen, T., Sakalem M., Tapia N., Baumuratov A., Kaltschmidt C., KaltschmidtB, Schöler H. R., Zhang W., Schwamborn J. C. (2014) Induced neural stem cells achieve long-term survival and functional integration in the adult mouse brain. Stem Cell Reports, accepted,


DOI: http://dx.doi.org/10.1016/j.stemcr.2014.06.017

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Mathematical theory proposed by Alan Turing in 1952 can explain the formation of fingers

Mathematical theory proposed by Alan Turing in 1952 can explain the formation of fingers | Amazing Science | Scoop.it
Researchers have shown that BMP and WNT proteins are the so-called 'Turing molecules' for creating embryonic fingers. Findings explain why polydactyly -- the development of extra fingers or toes -- is relatively common in humans, affecting up to one in 500 births, and confirms a fundamental theory first proposed by the founding father of computer science, Alan Turing, back in 1952.


Alan Turing, the British mathematician (1912-1954), is famous for a number of breakthroughs, which altered the course of the 20th century. In 1936 he published a paper, which laid the foundation of computer science, providing the first formal concept of a computer algorithm. He next played a pivotal role in the Second World War, designing the machines which cracked the German military codes, enabling the Allies to defeat the Nazis in several crucial battles. And in the late 1940's he turned his attention to artificial intelligence and proposed a challenge, now called the Turing test, which is still important to the field today.


His contribution to mathematical biology is less famous, but was no less profound. He published just one paper (1952), but it triggered a whole new field of mathematical enquiry into pattern formation. He discovered that a system with just 2 molecules could, at least in theory, create spotty or stripy patterns if they diffused and chemically interacted in just the right way.


His mathematical equations showed that starting from uniform condition (ie. a homogeneous distribution -- no pattern) they could spontaneously self-organise their concentrations into a repetitive spatial pattern. This theory has come to be accepted as an explanation of fairly simple patterns such as zebra stripes and even the ridges on sand dunes, but in embryology it has been resisted for decades as an explanation of how structures such as fingers are formed.


Now a group of researchers from the Multicellular Systems Biology lab at the CRG, led by ICREA Research Professor James Sharpe, has provided the long sought-for data which confirms that the fingers and toes are patterned by a Turing mechanism. "It complements their recent paper (Science 338:1476, 2012), which provided evidence that Hox genes and FGF signaling modulated a hypothetical Turing system. However, at that point the Turing molecules themselves were still not identified, and so this remained as the critical unsolved piece of the puzzle. The new study completes the picture, by revealing which signaling molecules act as the Turing system" says James Sharpe, co-author of the study.


The approach taken was that of systems biology -- combining experimental work with computational modelling. In this way, the two equal-first authors of the paper were able to iterate between the empirical and the theoretical: the lab-work of Jelena Raspopovic providing experimental data for the model, and the computer simulations of Luciano Marcon making predictions to be tested back in the lab.


By screening for the expression of many different genes, they found that two signalling pathways stood out as having the required activity patterns: BMPs and WNTs. They gradually constructed the minimal possible mathematical model compatible with all the data, and found that the two signalling pathways were linked through a non-diffusible molecule -- the transcription factor Sox9. Finally, they were able to make computational predictions about the effects of inhibiting these 2 pathways -- either individually, or in combination -- which predicted how the pattern of fingers should change. Strikingly, when the same experiments were done on small pieces of limb bud tissue cultured in a petri dish the same alterations in embryonic finger pattern were observed, confirming the computational prediction.

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Companion planets and large moons can increase an exoplanet's chance harbouring life

Companion planets and large moons can increase an exoplanet's chance harbouring life | Amazing Science | Scoop.it

Having a companion in old age is good for people — and, it turns out, might extend the chance for life on certain Earth-sized planets in the cosmos as well. Planets cool as they age. Over time their molten cores solidify and inner heat-generating activity dwindles, becoming less able to keep the world habitable by regulating carbon dioxide to prevent runaway heating or cooling.


But astronomers at the University of Washington and the University of Arizona have found that for certain planets about the size of our own, the gravitational pull of an outer companion planet could generate enough heat — through a process called tidal heating — to effectively prevent that internal cooling, and extend the inner world’s chance at hosting life.


UW astronomer Rory Barnes is second author of a paper published in the July issue of the Monthly Notices of the Royal Astronomical Society. The lead authors are graduate student Christa Van Laerhoven and planetary scientist Richard Greenberg at the University of Arizona.


Tidal heating results from the gravitational push and pull of the outer companion planet on its closer-in neighbor, Barnes said. The effect happens locally, so to speak, on Jupiter’s moons Io and Europa. The researchers showed that this phenomenon can take place on exoplanets — those outside the solar system — as well.


Using computer models, the researchers found the effect can occur on older Earth-sized planets in noncircular orbits in the habitable zone of low-mass stars, or those less than one-quarter the mass of the Sun. The habitable zone is that swath of space around a star just right to allow an orbiting rocky planet to sustain liquid water on its surface, thus giving life a chance.


“When the planet is closer to the star, the gravitational field is stronger and the planet is deformed into an American football shape. When farther from the star, the field is weaker and the planet relaxes into a more spherical shape,” Barnes said. “This constant flexing causes layers inside the planet to rub against each other, producing frictional heating.”


The outer planet is necessary, Barnes added, to keep the potentially habitable planet’s orbit noncircular. When a planet’s orbit is circular, the gravitational pull from its host star is constant, so its shape never changes, and there is no tidal heating.


And so, the researchers conclude, any discoveries of Earth-sized planets in the habitable zone of old, small stars should be followed by searches for outer companion planets that might improve the inner world’s chance at hosting life.

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Immortal jellyfish: Does it really live forever?

Immortal jellyfish: Does it really live forever? | Amazing Science | Scoop.it
The Turritopsis nutricula jellyfish has displayed a remarkable ability to regenerate its cells in times of crisis.


While it is often joked that cats have nine lives, a certain species of jellyfish has been deemed “immortal” by scientists who have observed its ability to, when in crisis, revert its cells to their earliest form and grow anew. That means that these tiny creatures, 4 mm to 5 mm long, potentially have infinite lives.
 
The creature, known scientifically as Turritopsis nutricula, was discovered in the Mediterranean Sea in 1883, but its unique regeneration was not known until the mid-1990s. How does the process work? If a mature Turritopsis is threatened — injured or starving, for example — it attaches itself to a surface in warm ocean waters and converts into a blob. From that state, its cells undergo transdifferentiation, in which the cells essentially transform into different types of cells. Muscle cells can become sperm or eggs, or nerve cells can change into muscle cells, “revealing a transformation potential unparalleled in the animal kingdom,” according to the original study of the species published in 1996.


But Turritopsis can — and do — die. Their regeneration only occurs after sexual maturation, therefore they can succumb to predators or disease in the polyp stage. But because the jellyfish are the only known animal with this “immortality,” scientists are studying them closely, with the hopes of applying what they learn to issues such as human aging and illness.

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The Strangeness of Quantum Mechanics and the Delayed Choice Quantum Eraser

The Strangeness of Quantum Mechanics and the Delayed Choice Quantum Eraser | Amazing Science | Scoop.it

Feynman once said that all the surprising wisdom of quantum mechanics is hiding in the double slit experiment. If you think about it carefully enough, you will ultimately figure out all the important and amazing new features of the world that quantum mechanics uncovers.

However, many people disagree and they tend to expect that every time they add a new prism or a new laser or a beam splitter to an experiment, the situation becomes more confusing than ever before and there is a new "hope" that a disagreement with quantum mechanics will be found.

More complex experiments only make the situation more contrived - but the basic scheme of how quantum mechanics works is unchanged. Also, all the errors that lead most people to believe that there is something paradoxical about quantum mechanics keep on repeating themselves.

The list of important experiments:

  1. The ordinary double-slit experiment
  2. Wheeler's delayed choice experiment
  3. An EPR experiment with a single pair of particles
  4. Delayed choice quantum eraser
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New correction to speed of light could explain SN1987 dual-pulse neutrino burst

New correction to speed of light could explain SN1987 dual-pulse neutrino burst | Amazing Science | Scoop.it

The effect of gravity on virtual electron–positron pairs as they propagate through space could lead to a violation of Einstein's equivalence principle, according to calculations by James Franson at the University of Maryland, Baltimore County. While the effect would be too tiny to be measured directly using current experimental techniques, it could explain a puzzling anomaly observed during the famous SN1987 supernova of 1987.


In modern theoretical physics, three of the four fundamental forces – electromagnetism, the weak nuclear force and the strong nuclear force – are described by quantum mechanics. The fourth force, gravity, does not currently have a quantum formulation and is best described by Einstein's general theory of relativity. Reconciling relativity with quantum mechanics is therefore an important and active area of physics.


An open question for theoretical physicists is how gravity acts on a quantum object such as a photon. Astronomical observations have shown repeatedly that light is attracted by a gravitational field. Traditionally, this is described using general relativity: the gravitational field bends space–time, and the light is slowed down (and slightly deflected) as it passes through the curved region. In quantum electrodynamics, a photon propagating through space can occasionally annihilate with itself, creating a virtual electron–positron pair. Soon after, the electron and positron recombine to recreate the photon. If they are in a gravitational potential then, for the short time they exist as massive particles, they feel the effect of gravity. When they recombine, they will create a photon with an energy that is shifted slightly and that travels slightly slower than if there was no gravitational potential.


Franson scrutinized these two explanations for why light slows down as it passes through a gravitational potential. He decided to calculate how much the light should slow down according to each theory, anticipating that he would get the same answer. However, he was in for a surprise: the predicted changes in the speed of light do not match, and the discrepancy has some very strange consequences.


Franson calculated that, treating light as a quantum object, the change in a photon's velocity depends not on the strength of the gravitational field, but on the gravitational potential itself. However, this leads to a violation of Einstein's equivalence principle – that gravity and acceleration are indistinguishable – because, in a gravitational field, the gravitational potential is created along with mass, whereas in a frame of reference accelerating in free fall, it is not. Therefore, one could distinguish gravity from acceleration by whether a photon slows down or not when it undergoes particle–antiparticle creation.


An important example is a photon and a neutrino propagating in parallel through space. A neutrino cannot annihilate to create an electron–positron pair, so the photon will slow down more than the neutrino as they pass through a gravitational field, potentially letting the neutrino travel faster than light through that region of space. However, if the problem is viewed in a frame of reference falling freely into the gravitational field, neither the photon nor the neutrino slows down at all, so the photon continues to travel faster than the neutrino.


While the idea that the laws of physics can be dependent on one's frame of reference seems nonsensical, it could explain an anomaly in the 1987 observation of supernova SN1987a. An initial pulse of neutrinos was detected 7.7 hours before the first light from SN1987a reached Earth. This was followed by a second pulse of neutrinos, which arrived about three hours before the supernova light. Supernovae are expected to emit large numbers of neutrinos and the three-hour gap between the second burst of neutrinos and the arrival of the light agrees with the current theory of how a star collapses to create a supernova.


The first pulse of neutrinos is generally thought to be unrelated to the supernova. However, the probability of such a coincidence is statistically unlikely. If Franson's results are correct, then the 7.7-hour gap between the first pulse of neutrinos and the arrival of the light could be explained by the gravitational potential of the Milky Way slowing down the light. This does not explain why two neutrino pulses preceded the light, but Franson suggests the second pulse could be related to a two-step collapse of the star.


The research is published in the New Journal of Physics.

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Infospectives's curator insight, August 2, 2014 1:51 PM

I love this..."NEW' correction to the speed of light.  Since when did we start messing about with it?

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NASA's next Mars rover will make oxygen, to sustain life

NASA's next Mars rover will make oxygen, to sustain life | Amazing Science | Scoop.it

For 17 years, NASA rovers have laid down tire tracks on Mars. But details the space agency divulged this week about its next Martian exploration vehicle underscored NASA's ultimate goal. Footprints are to follow someday.


The last three rovers -- Spirit, Opportunity and Curiosity -- confirmed the Red Planet's ability to support life and searched for signs of past life. The Mars rover of the next decade will hone in on ways to sustain future life there, human life.


"The 2020 rover will help answer questions about the Martian environment that astronauts will face and test technologies they need before landing on, exploring and returning from the Red Planet," said NASA's William Gerstenmaier who works on human missions. This will include experiments that convert carbon dioxide in the Martian atmosphere into oxygen "for human respiration." Oxygen could also be used on Mars in making rocket fuel that would allow astronauts to refill their tanks.


The 2020 rover is the near spitting image of Curiosity and NASA's Jet Propulsion Laboratory announced plans to launch the new edition not long after Curiosity landed on Mars in 2012. But the 2020 rover has new and improved features. The Mars Oxygen ISRU Experiment, or MOXIE for short, is just one. There are super cameras that will send back 3D panoramic images and spectrometers that will analyze the chemical makeup of minerals with an apparent eye to farming.


"An ability to live off the Martian land would transform future exploration of the planet," NASA said in a statement. The 2020 rover will also create a job for a future mission to complete, once the technology emerges to return to Earth from Mars. It will collect soil samples to be sent back for lab analysis at NASA.

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Eric Chan Wei Chiang's curator insight, August 2, 2014 10:57 PM

Oxygen production and minerals for farming would pave the way for manned missions and perhaps even a small colony.  The next step would be Mars sample return mission: 

http://en.wikipedia.org/wiki/Mars_sample_return_mission

 

Read more scoops on Mars here:

http://www.scoop.it/t/world-of-tomorrow/?tag=Mars

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Nanostructured metal-oxide catalyst efficiently converts CO2 to methanol

Nanostructured metal-oxide catalyst efficiently converts CO2 to methanol | Amazing Science | Scoop.it

Scanning tunneling microscope image of a cerium-oxide and copper catalyst (CeOx-Cu) used in the transformation of carbon dioxide (CO2) and hydrogen (H2) gases.


Scientists at Brookhaven National Laboratory have discovered a new catalytic system for converting carbon dioxide (CO2) to methanol — a key commodity used to create a wide range of industrial chemicals and fuels. With significantly higher activity than other catalysts now in use, the new system could make it easier to get normally unreactive CO2 to participate in these reactions.


“Developing an effective catalyst for synthesizing methanol from CO2 could greatly expand the use of this abundant gas as an economical feedstock,” said Brookhaven chemist Jose Rodriguez, who led the research. “It’s even possible to imagine a future in which such catalysts help capture CO2 emitted from methanol-powered combustion engines and fuel cells, and recycling it to synthesize new fuel,” he said.

That future, of course, will be determined by a variety of factors, including economics.


The research team, which included scientists from Brookhaven, the University of Seville in Spain, and Central University of Venezuela, describes their results in the August 1, 2014, issue of the journal Science.


Because CO2 is normally such a reluctant participant in chemical reactions, interacting weakly with most catalysts, it’s also rather difficult to study. The new studies required the use of newly developed in-situ (or on-site, meaning under reaction conditions) imaging and chemical “fingerprinting” techniques.


These techniques allowed the scientists to peer into the dynamic evolution of a variety of catalysts as they operated in real time. The scientists also used computational modeling at the University of Seville and the Barcelona Supercomputing Center to provide a molecular description of the methanol synthesis mechanism.


The team was particularly interested in exploring a catalyst composed of copper and ceria (cerium-oxide) nanoparticles, sometimes also mixed with titania. The scientists’ previous studies with such metal-oxide nanoparticle catalysts have demonstrated their exceptional reactivity in a variety of reactions. In those studies, the interfaces of the two types of nanoparticles turned out to be critical to the reactivity of the catalysts, with highly reactive sites forming at regions where the two phases meet.


To explore the reactivity of such dual particle catalytic systems in converting CO2 to methanol, the scientists used spectroscopic techniques to investigate the interaction of CO2 with plain copper, plain cerium-oxide, and cerium-oxide/copper surfaces at a range of reaction temperatures and pressures. Chemical fingerprinting was combined with computational modeling to reveal the most probable progression of intermediates as the reaction from CO2 to methanol proceeded.


These studies revealed that the metal component of the catalysts alone could not carry out all the chemical steps necessary for the production of methanol. The most effective binding and activation of CO2 occurred at the interfaces between metal and oxide nanoparticles in the cerium-oxide/copper catalytic system.


“The key active sites for the chemical transformations involved atoms from the metal [copper] and oxide [ceria or ceria/titania] phases,” said Jesus Graciani, a chemist from the University of Seville and first author on the paper. The resulting catalyst converts CO2 to methanol more than a thousand times faster than plain copper particles, and almost 90 times faster than a common copper/zinc-oxide catalyst currently in industrial use.

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Eric Chan Wei Chiang's curator insight, August 2, 2014 11:21 PM

The transformation of CO2 into alcohols or other hydrocarbon compounds is challenging because catalysing the formation of carbon-carbon bonds is very difficult. To illustrate, Victor Grignard won the Nobel Prize in 1912 for developing reagents which forms carbon-carbon bonds.


Nonetheless, this technology has vast implications in space exploration and sustainable energy:

http://www.scoop.it/t/world-of-tomorrow/?tag=Space+Exploration

http://www.scoop.it/t/aquascaping-and-nature/?tag=Sustainable+Energy

 

On carbon fixation, an artificial leaf devised using real chloroplast is described here: http://sco.lt/7MI8mX

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The Visual Microphone - Passive Recovery of Sound from Just Visual Information

The Visual Microphone - Passive Recovery of Sound from Just Visual Information | Amazing Science | Scoop.it

An unlikely method of surveillance has emerged in the form of crisp packets, after researchers reconstructed speech by observing tiny vibrations using a "visual microphone".


Researchers at the Massachusetts Institute of Technology (MIT), Microsoft and Adobe achieved this by developing an algorithm that can recreate sound based on silent video footage of nearby objects.


As well as packets of crisps, the algorithm can record sound through the vibrations of other items, like aluminum foil, glasses of water and house plants.

"When sound hits an object, it causes the object to vibrate," said Abe Davis, an electrical engineering graduate student at MIT and first author of a paper that details the findings. "The motion of this vibration creates a very subtle visual signal that's usually invisible to the naked eye.


"In our work, we show how using only a video of the object and a suitable processing algorithm, we can extract these minute vibrations and partially recover the sounds that produce them - letting us turn everyday visible objects into visual microphones."


Through this process, Davis and his team were first able to decipher the tune of Mary had a little lamb through vibrations in the leaves of a plant.


To test the sound-processing algorithm, the method was then tested on a bag of crisps from behind sound-proof glass. Remarkably, the visual microphone was able to pick up the words to the same nursery rhymeThe results of the experiment have already led privacy advocates to warn about the implications of how this technology may be used.

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Flores bones show features of Down syndrome, not a new "hobbit" human

Flores bones show features of Down syndrome, not a new "hobbit" human | Amazing Science | Scoop.it

In October 2004, excavation of fragmentary skeletal remains from the island of Flores in Indonesia yielded what was called "the most important find in human evolution for 100 years." Its discoverers dubbed the find Homo floresiensis, a name suggesting a previously unknown species of human.


Now detailed reanalysis by an international team of researchers including Robert B. Eckhardt, professor of developmental genetics and evolution at Penn State, Maciej Henneberg, professor of anatomy and pathology at the University of Adelaide, and Kenneth Hsü, a Chinese geologist and paleoclimatologist, suggests that the single specimen on which the new designation depends, known as LB1, does not represent a new species. Instead, it is the skeleton of a developmentally abnormal human and, according to the researchers, contains important features most consistent with a diagnosis of Down syndrome.

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The MX3D Robot is 3D Printing Large Objects in Steel at 3 Meters per Hour Speed

The MX3D Robot is 3D Printing Large Objects in Steel at 3 Meters per Hour Speed | Amazing Science | Scoop.it

The MX3D robot arm extrudes steel with 360-degree articulation. 


The chair shown above was 3D printed -- not in plastic, but in stainless steel. "It was born out of frustration with the limitations in existing printers," says Amsterdam-based furniture designer Joris Laarman, 34.


To create the Dragon chair (shown viewed from above), Laarman worked with materials researchers at the Institute for Advanced Architecture of Catalonia to develop the multi-axis MX3D printer. The machine combines an MIG (metal inert gas) welding machine with a robotic arm. "By adding small amounts of molten metal at a time, we are able to print lines in mid air without support," Laarman says. As the arm is flexible -- not fixed to an axis like the heads of most small 3D printers -- it allows the designer to create complex shapes. 


Laarman's ultimate aim, he says, is to "get 3D printing out of the world of funny little gadgets". His lab is already in conversation with construction companies and shipyards about uses for the device, and Laarman is working with Autodesk to bring it to market. "This is still unexplored territory," he adds. "But we think digital fabrication has to scale up to grow up."

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New material combines two semiconductor sheets three atomic layers thick to create ultra-thin solar cells

New material combines two semiconductor sheets three atomic layers thick to create ultra-thin solar cells | Amazing Science | Scoop.it

Semiconductor heterostructures form the cornerstone of many electronic and optoelectronic devices and are traditionally fabricated using epitaxial growth techniques. More recently, heterostructures have also been obtained by vertical stacking of two-dimensional crystals, such as graphene and related two-dimensional materials. These layered designer materials are held together by van der Waals forces and contain atomically sharp interfaces. Here, we report on a type-II van der Waals heterojunction made of molybdenum disulfide and tungsten diselenide monolayers. The junction is electrically tunable, and under appropriate gate bias an atomically thin diode is realized. Upon optical illumination, charge transfer occurs across the planar interface and the device exhibits a photovoltaic effect. Advances in large-scale production of two-dimensional crystals could thus lead to a new photovoltaic solar technology.


Tungsten diselenide is a semiconductor which consists of three atomic layers. One layer of tungsten is sandwiched between two layers of selenium atoms. “We had already been able to show that tungsten diselenide can be used to turn light into electric energy and vice versa”, says Thomas Mueller. But a solar cell made only of tungsten diselenide would require countless tiny metal electrodes tightly spaced only a few micrometers apart. If the material is combined with molybdenium disulphide, which also consists of three atomic layers, this problem is elegantly circumvented. The heterostructure can now be used to build large-area solar cells. 

When light shines on a photoactive material single electrons are removed from their original position. A positively charged hole remains, where the electron used to be. Both the electron and the hole can move freely in the material, but they only contribute to the electrical current when they are kept apart so that they cannot recombine. 

To prevent recombination of electrons and holes, metallic electrodes can be used, through which the charge is sucked away - or a second material is added. “The holes move inside the tungsten diselenide layer, the electrons, on the other hand, migrate into the molybednium disulphide”, says Thomas Mueller. Thus, recombination is suppressed.

This is only possible if the energies of the electrons in both layers are tuned exactly the right way. In the experiment, this can be done using electrostatic fields. Florian Libisch and Professor Joachim Burgdörfer (TU Vienna) provided computer simulations to calculate how the energy of the electrons changes in both materials and which voltage leads to an optimum yield of electrical power.

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End of chemotherapy within 20 years as pioneering DNA sequencing project is launched in the UK

End of chemotherapy within 20 years as pioneering DNA sequencing project is launched in the UK | Amazing Science | Scoop.it

Cancer patients will no longer have to put up with the debilitating side-effects of chemotherapy after David Cameron launched a new landmark project to map the genetic causes of the disease.


David Cameron, the prime minister, said the venture would ‘unlock the power of DNA’ to deliver ‘better tests, better drugs and better care for patients.’ "As our plan becomes a reality, I believe we will be able to transform how devastating diseases are diagnosed and treated in the NHS and across the world,” he said.


The first few hundred pilot participants in London, Cambridge and Newcastle have already donated DNA samples and the project is expected to be completed 2018. "20 years from now there will be therapies, instead of chemo, that will be a much more targeted approach to treatment,” said Prof Jeremy Farrer, head of the Wellcome Trust.


“We will look back in 20 years time and the blockbuster chemotherapy drugs that gave you all those nasty side effects will be a thing of the past and we will think ‘gosh what an era that was’. “Understanding humanity’s genetic code is not only going to be fundamental to the medicine of the future. It is essential part of medicine today. In rare congenital disease, in cancer and in infections, genomic insights are already transforming diagnosis and treatment.” Prof Farrer also predicted that genome sequencing to find the causes of the disease will become standard within our lifetime.


The first human genome was sequenced in 2003 following 13 years of work at a cost of £2 billion. Now it takes around two days and costs just £1,000.


A genome consists of a person’s 20,000 or so genes and the DNA in between. Each genome consists of a code of 3 billion letters. Over the next four years, about 75,000 patients with cancer and rare diseases, plus their close relatives, will have their whole genetic codes, or genomes, sequenced.


Cancer patients will have the DNA of both healthy and tumour cells mapped, making up the 100,000 total. Scientists expect the project to be pivotal to the development of future personalised treatments based on genetics, with the potential to revolutionise medicine.


A £78 million partnership between Genomics England, the body set up by the Department of Health to oversee the project, and the Californian DNA sequencing technology company Illumina was unveiled by Mr Cameron today.


Illumina, originally "spun out" by Cambridge University scientists, will invest around £162 million into the project over its lifetime. By the end of next year that figure is expected to have risen to about 10,000.

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Global warming turbo-charges Pacific trade winds, highest on record since 1860

Global warming turbo-charges Pacific trade winds, highest on record since 1860 | Amazing Science | Scoop.it
New research has found rapid warming of the Atlantic Ocean, likely caused by global warming, has turbocharged Pacific Equatorial trade winds. Currently the winds are at a level never before seen on observed records, which extend back to the 1860s.


The increase in these winds has caused eastern tropical Pacific cooling, amplified the Californian drought, accelerated sea level rise three times faster than the global average in the Western Pacific and has slowed the rise of global average surface temperatures since 2001.


It may even be responsible for making El Nino events less common over the past decade due to its cooling impact on ocean surface temperatures in the eastern Pacific.


We were surprised to find the main cause of the Pacific climate trends of the past 20 years had its origin in the Atlantic Ocean," said co-lead author Dr Shayne McGregor from the ARC Centre of Excellence for Climate System Science (ARCCSS) at the University of New South Wales.


"It highlights how changes in the climate in one part of the world can have extensive impacts around the globe." The record-breaking increase in Pacific Equatorial trade winds over the past 20 years had, until now, baffled researchers.


Originally, this trade wind intensification was considered to be a response to Pacific decadal variability. However, the strength of the winds was much more powerful than expected due to the changes in Pacific sea surface temperature. Another riddle was that previous research indicated that under global warming scenarios Pacific Equatorial Trade winds would slow down over the coming century.


The solution was found in the rapid warming of the Atlantic Ocean basin, which has created unexpected pressure differences between the Atlantic and Pacific. This has produced wind anomalies that have given Pacific Equatorial trade winds an additional big push.


"The rapid warming of the Atlantic Ocean created high pressure zones in the upper atmosphere over that basin and low pressure zones close to the surface of the ocean," said Prof Axel Timmermann co-lead and corresponding author from the University of Hawaii.

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Dinosaurs shrank to evolve into birds over a 50 million years time span

Dinosaurs shrank to evolve into birds over a 50 million years time span | Amazing Science | Scoop.it

Huge meat-eating dinosaurs (Theropods) underwent 12 stages of miniaturization and shrank steadily over 50 million years to evolve into small, flying birds, researchers say. The branch of theropod dinosaurs which gave rise to modern birds decreased inexorably in size from 163kg beasts that roamed the land, to birds weighing less than 1kg over the period.


The radical transformation began around 200 million years ago and was likely driven by a move to the trees where creatures with smaller, lighter bodies and other features, such as large eyes for 3D vision, fared better than others.


Scientists pieced together the dinosaurs' sustained shrinkage after analysing more than 1,500 anatomical features of 120 species of theropods and early birds.


The evolutionary tree reveals that the theropod ancestors of modern birds underwent 12 substantial decreases in size that led to archaeopteryx, the earliest known bird on Earth. The rate at which they evolved distinct features, such as feathers, wings and wishbones, was four times faster than adaptations in other dinosaurs.


"Birds evolved through a unique phase of sustained miniaturisation in dinosaurs," said Michael Lee at the University of Adelaide. "Being smaller and lighter in the land of giants, with rapidly evolving anatomical adaptations, provided these bird ancestors with new ecological opportunities, such as the ability to climb trees, glide and fly. Ultimately, this evolutionary flexibility helped birds survive the deadly meteorite impact which killed off all their dinosaurian cousins," he added. The study is published in the journal, Science.


The steady reduction in size saw the two-legged land-based theropods evolve new bird-like features, including shorter snouts, smaller teeth and insulating feathers.


Gareth Dyke, a vertebrate palaeontologist and co-author of the study at Southampton University said: "The dinosaurs most closely related to birds are all small, and many of them, such as the aptly named Microraptor, had some ability to climb and glide."


In an accompanying article, Michael Benton at Bristol University, said that the long-term trend that led to modern birds was probably shaped by the animals taking up in new habitats. "The crucial driver may have been a move to the trees, perhaps to escape from predation or to exploit new food resources," he writes.

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Sending Red Light Through The Skull To Influence Brain Activity Using Red-Shifted Cruxhalorhodopsin named Jaws

Sending Red Light Through The Skull To Influence Brain Activity Using Red-Shifted Cruxhalorhodopsin named Jaws | Amazing Science | Scoop.it
Genetically engineered protein responds remotely to red light.


A team of biological engineers has developed a light-sensitive protein that permits scientists to control activity inside the brains of mice from outside the rodents’ skulls. The protein, called Jaws, promises to expand scientists’ ability to study brain activity in experimental animals and -- eventually -- humans. Ultimately, it holds the prospect of facilitating treatment of human conditions such as epilepsy.


Researchers are also using the protein to treat eye disease in experimental animals. Here, an immediate goal is therapy for certain eye ailments in humans.


Scientists use optogenetics, as the technology is known, to study the behavior and pathology of experimental animals’ brains by shining light on proteins known as opsins. Introduced into the brain aboard viruses, the opsins respond to the light by suppressing or stimulating electrical signals in brain cells. Optogenetic inhibition of the electrical activity of neurons enables the causal assessment of their contributions to brain functions. Red light penetrates deeper into tissue than other visible wavelengths. The red-shifted cruxhalorhodopsin, Jaws, derived from Haloarcula (Halobacteriumsalinarum (strain Shark) and engineered to result in red light–induced photocurrents three times those of earlier silencers. Jaws exhibits robust inhibition of sensory-evoked neural activity in the cortex and results in strong light responses when used in retinas of retinitis pigmentosa model mice.


The opsins normally used in brain studies are sensitive to blue, green, or yellow light. Because bodily tissue absorbs those colors easily, the sources of such light must lie inside the brain. Typically, the light is delivered through an optical fiber implanted in an experimental animal’s brain. Jaws can noninvasively mediate transcranial optical inhibition of neurons deep in the brains of awake mice. The noninvasive optogenetic inhibition opened up by Jaws enables a variety of important neuroscience experiments and offers a powerful general-use chloride pump for basic and applied neuroscience.


A team led by Ed Boyden, associate professor of biological engineering and brain and cognitive sciences at the Massachusetts Institute of Technology, in Cambridge, reporting in Nature Neuroscience, demonstrated that red light shone from outside a mouse’s head can influence the Jaws protein up to three millimeters deep inside the brain. In fact, Boyden said, "we think the light goes further into the brain." A mouse’s brain is only about four millimeters thick.


"This is a huge advance, in that it allows for much deeper penetration of effective light," said David Lyon, an associate professor of anatomy and neurobiology at the University of California, Irvine School of Medicine. Lyon was not involved in the research on Jaws.

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NASA tests ‘impossible’ no-fuel quantum space engine – and it actually seems to work

NASA tests ‘impossible’ no-fuel quantum space engine – and it actually seems to work | Amazing Science | Scoop.it
NASA didn't set out to confirm the feasibility of a seemingly impossible fuel-less thruster design, but it seems they did exactly that.


NASA has been testing new space travel technologies throughout its entire history, but the results of its latest experiment may be the most surprising yet — if they can be confirmed and hold up. At a conference in Cleveland, Ohio, scientists with NASA's Eagleworks Laboratories in Houston, Texas, presented a paper indicating they had achieved a small amount of thrust from a container that had no traditional fuels, only microwaves, bouncing around inside of it. If the results can be replicated reliably and scaled up — and that's a big "if," since NASA only produced them on a very small scale over a two-day period — they could ultimately result in ultra-light-weight, ultra-fast spacecrafts that could carry humans to Mars in weeks instead of months, and to the nearest star system outside our own (Proxima Centurai) in just about 30 years.


The type of container NASA tested was based on a model for a new space engine that doesn't use weighty liquid propellant or nuclear reactors, called a Cannae Drive. The idea is that microwaves bouncing from end-to-end of a specially designed, unevenly-shaped container can create a difference in radiation pressure, causing thrust to be exerted toward the larger end of the container. A similar type of technology called an EmDrive has been demonstrated to work in small scale trials by Chinese and Argentine scientists.


While the amount of thrust generated in these NASA's tests was lower than previous trials — between 30 and 50 micronewtons, way less than even the weight of an iPhone, as Nova points out — the fact that any thrust whatsoever is generated without an onboard source of fuel seems to violate the conservation of momentum, a bedrock in the laws of physics.


Most impressively, the NASA team specifically built two Cannae Drives, including one that was designed to fail, and instead it worked. As the scientists write in their paper abstract: "thrust was observed on both test articles, even though one of the test articles was designed with the expectation that it would not produce thrust." That suggests the drive is "producing a force that is not attributable to any classical electromagnetic phenomenon," the scientists write. It may instead be interacting with the quantum vacuum — the lowest energetic state possible — but the scientists don't have much evidence to support this idea yet.


There are many reasons to be skeptical: the inventor of the Cannae Drive, Guido Fetta, has only a Bachelor’s Degree in Chemical Engineering and is operating his company Cannae as a for-profit venture. Still, the fact that such results were produced by NASA scientists is promising and should warrant further investigation.

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Mapping the optimal route between two quantum states

Mapping the optimal route between two quantum states | Amazing Science | Scoop.it
As a quantum state collapses from a quantum superposition to a classical state or a different superposition, it will follow a path known as a quantum trajectory.


In a recent paper in Nature, scientists from the University of Rochester, University of California at Berkeley and Washington University in St. Louis have shown that it is possible to track these quantum trajectories and compare them to a recently developed theory for predicting the most likely path a system will take between two states.


Andrew N. Jordan, professor of physics at the University of Rochester and one of the authors of the paper, and his group had developed this new theory in an earlier paper. The results published this week show good agreement between theory and experiment.


For their experiment, the Berkeley and Washington University teams devised a superconducting qubit with exceptional coherence properties, permitting it to remain in a quantum superposition during the continuous monitoring. The experiment actually exploited the fact that any measurement will perturb a quantum system. This means that the optimal path will come about as a result of the continuous measurement and how the system is being driven from one quantum state to another.


Kater Murch, co-author and assistant professor at Washington University in St. Louis, explained that a key part of the experiment was being able to measure each of these trajectories while the system was changing, something that had not been possible until now.


Jordan compares the experiment to watching butterflies make their way one by one from a cage to nearby trees. "Each butterfly's path is like a single run of the experiment," said Jordan. "They are all starting from the same cage, the initial state, and ending in one of the trees, each being a different end state." By watching the quantum equivalent of a million butterflies make the journey from cage to tree, the researchers were in effect able to predict the most likely path a butterfly took by observing which tree it landed on (known as post-selection in quantum physics measurements), despite the presence of a wind, or any disturbance that affects how it flies, which is similar to the effect measuring has on the system.


"The experiment demonstrates that for any choice of final quantum state, the most likely or 'optimal path' connecting them in a given time can be found and predicted," said Jordan. "This verifies the theory and opens the way for active quantum control techniques." He explained that only if you know the most likely path is it possible to set up the system to be in the desired state at a specific time.


Via Jocelyn Stoller
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The social origins of intelligence in the brain

The social origins of intelligence in the brain | Amazing Science | Scoop.it

By studying the injuries and aptitudes of Vietnam War veterans who suffered penetrating head wounds during the war, researchers have found that brain regions that contribute to optimal social functioning are also vital to general intelligence and emotional intelligence.


This finding, reported in the journal Brain, bolsters the view that general intelligence emerges from the emotional and social context of one’s life.

“We are trying to understand the nature of general intelligence and to what extent our intellectual abilities are grounded in social cognitive abilities,” said Aron Barbey, a University of Illinois professor of neuroscience, psychology, and speech and hearing science.


Barbey, an affiliate of the Beckman Institute and he Institute for Genomic Biology at the University of Illinois, led the new study with an international team of collaborators.


The study involved 144 Vietnam veterans injured by shrapnel or bullets that penetrated the skull, damaging distinct brain tissues while leaving neighboring tissues intact. Using CT scans, the scientists painstakingly mapped the affected brain regions of each participant, then pooled the data to build a collective map of the brain.


The researchers used a battery of carefully designed tests to assess participants’ intellectual, emotional and social capabilities. They then looked for damage in specific brain regions tied to deficits in the participants’ ability to navigate intellectual, emotional or social realms. Social problem solving in this analysis primarily involved conflict resolution with friends, family and peers at work.


As in their earlier studies of general intelligence and emotional intelligence, the researchers found that regions of the frontal cortex (at the front of the brain), the parietal cortex (further back near the top of the head) and the temporal lobes (on the sides of the head behind the ears) are all implicated in social problem solving. The regions that contributed to social functioning in the parietal and temporal lobes were located only in the brain’s left hemisphere, while both left and right frontal lobes were involved.

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Eric Chan Wei Chiang's curator insight, August 2, 2014 12:30 PM

There is a popular myth that humans use no more than 10% of their brains throughout their entire life. This has been shown to be untrue as brain damage consistently results in loss of function. Nonetheless, this myth provided the premise for some great movies such as the 2014 film, Lucy 

http://en.wikipedia.org/wiki/Lucy_(2014_film)

 

Read more scoops on the brain here:

http://www.scoop.it/t/biotech-and-beyond/?tag=Brain

Helen Teague's curator insight, August 3, 2014 9:32 AM

From Dr. Stefan Gruenwald:

By studying the injuries and aptitudes of Vietnam War veterans who suffered penetrating head wounds during the war, researchers have found that brain regions that contribute to optimal social functioning are also vital to general intelligence and emotional intelligence.

 

This finding, reported in the journal Brain, bolsters the view that general intelligence emerges from the emotional and social context of one’s life.

“We are trying to understand the nature of general intelligence and to what extent our intellectual abilities are grounded in social cognitive abilities,” said Aron Barbey, a University of Illinois professor of neuroscience, psychology, and speech and hearing science.

 

Barbey, an affiliate of the Beckman Institute and he Institute for Genomic Biology at the University of Illinois, led the new study with an international team of collaborators.

 

The study involved 144 Vietnam veterans injured by shrapnel or bullets that penetrated the skull, damaging distinct brain tissues while leaving neighboring tissues intact. Using CT scans, the scientists painstakingly mapped the affected brain regions of each participant, then pooled the data to build a collective map of the brain.

 

The researchers used a battery of carefully designed tests to assess participants’ intellectual, emotional and social capabilities. They then looked for damage in specific brain regions tied to deficits in the participants’ ability to navigate intellectual, emotional or social realms. Social problem solving in this analysis primarily involved conflict resolution with friends, family and peers at work.

 

As in their earlier studies of general intelligence and emotional intelligence, the researchers found that regions of the frontal cortex (at the front of the brain), the parietal cortex (further back near the top of the head) and the temporal lobes (on the sides of the head behind the ears) are all implicated in social problem solving. The regions that contributed to social functioning in the parietal and temporal lobes were located only in the brain’s left hemisphere, while both left and right frontal lobes were involved.

Jocelyn Stoller's curator insight, August 13, 2014 4:55 AM

Strange that CT scans were used. High resolution Functional MRI would show both structure and activity. Other imaging methods such as optogenetics, MEG, TMS, BOLD, etc. could also help to pinpoint these areas without using radiation on an already-injured brain.

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Can Winograd Schemas Replace Turing Test for Defining Human-Level AI?

Can Winograd Schemas Replace Turing Test for Defining Human-Level AI? | Amazing Science | Scoop.it

Earlier this year, a chatbot called Eugene Goostman "beat" a Turing Test for artificial intelligence as part of a contest organized by a U.K. university. Almost immediately, it became obvious that rather than proving that a piece of software had achieved human-level intelligence, all that this particular competition had shown was that a piece of software had gotten fairly adept at fooling humans into thinking that they were talking to another human, which is very different from a measure of the ability to "think." In fact, some observers didn't think the bot was very clever at all.


Clearly, a better test is needed, and we may have one, in the form of a type of question called a Winograd schema that's easy for a human to answer, but a serious challenge for a computer.


The problem with the Turing Test is that it's not really a test of whether an artificial intelligence program is capable of thinking: it's a test of whether an AI program can fool a human. And humans are really, really dumb. We fall for all kinds of tricks that a well-programmed AI can use to convince us that we're talking to a real person who can think.


For example, the Eugene Goostman chatbot pretends to be a 13-year-old boy, because 13-year-old boys are often erratic idiots (I've been one), and that will excuse many circumstances in which the AI simply fails. So really, the chat bot is not intelligent at all—it's just really good at making you overlook the times when it's stupid, while emphasizing the periodic interactions when its algorithm knows how to answer the questions that you ask it.


Conceptually, the Turing Test is still valid, but we need a better practical process for testing artificial intelligence. A new AI contest, sponsored by Nuance Communications and CommonsenseReasoning.org, is offering a US $25,000 prize to an AI that can successfully answer what are called Winograd schemas, named after Terry Winograd, a professor of computer science at Stanford University.


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