Going quantum with radio waves

Cecile G. Tamura

Weak radio signals are not just a challenge for people trying to find their favorite radio station, but alfavouriteagnetic resonance imaging (MRI) scanners at hospitals, as well as for the telescopes scientists use to peer into space.

The usual answer for a weak radio signal is to locate a strong signal, for example, by picking an alternate radio station or by moving to the opposite side of the room. However, imagine a scenario in which we could simply listen more cautiously.

Now, scientists at the Delft University of Technology have found the answer to this. They have devised a quantum circuit to listen to the weakest radio signal allowed by quantum mechanics.

In a quantum leap in radio frequency detection, researchers in the group of Prof. Gary Steele in Delft demonstrated the detection of photons or quanta of energy, the weakest signals allowed by the theory of quantum mechanics.

Gely et al. used a superconducting qubit, initially developed for circuit quantum electrodynamics (cQED) and quantum information processing for microwaves, to directly observe the quantization of radio-frequency electromagnetic fields stored in a photonic microresonator. They were then able to manipulate the quantum state of the radio-frequency field, forming one- and two-photon Fock states within the microresonator, and analyze how the system interacts dynamically with its environment. The cQED approach could be used for fundamental studies in quantum thermodynamics and also find practical application in imaging.

Scientists Discover Atomic-resolution Details of Brain Signaling

Scientists have revealed never-before-seen details of how our brain sends rapid-fire messages between its cells. They mapped the 3-D atomic structure of a two-part protein complex that controls the release of signaling chemicals, called neurotransmitters, from brain cells.
Understanding how cells release those signals in less than one-thousandth of a second could help launch a new wave of research on drugs for treating brain disorders.

 
The experiments, at the Linac Coherent Light Source (LCLS) X-ray laser at the Department of Energy’s SLAC National Accelerator Laboratory, build upon decades of previous research at Stanford University, Stanford School of Medicine and SLAC. Researchers reported their latest findings today in the journal Nature.

“This is a very important, exciting advance that may open up possibilities for targeting new drugs to control neurotransmitter release. Many mental disorders, including depression, schizophrenia and anxiety, affect neurotransmitter systems,” said Axel Brunger, the study’s principal investigator. He is a professor at Stanford School of Medicine and SLAC and a Howard Hughes Medical Institute investigator.

“Both parts of this protein complex are essential,” Brunger said, “but until now it was unclear how its two pieces fit and work together.”
Unraveling the Combined Secrets of Two Proteins

The two protein parts are known as neuronal SNAREs and synaptotagmin-1.

Earlier X-ray studies, including experiments at SLAC’s Stanford Synchrotron Radiation Lightsource (SSRL) nearly two decades ago, shed light on the structure of the SNARE complex, a helical protein bundle found in yeasts and mammals. SNAREs play a key role in the brain’s chemical signaling by joining, or “fusing,” little packets of neurotransmitters to the outer edges of neurons, where they are released and then dock with chemical receptors in another neuron to trigger a response.

A ‘Smoking Gun’ for Neurotransmitter Release

In this latest research, the scientists found that when the SNAREs and synaptotagmin-1 join up, they act as an amplifier for a slight increase in calcium concentration, triggering a gunshot-like release of neurotransmitters from one neuron to another. They also learned that the proteins join together before they arrive at a neuron’s membrane, which helps to explain how they trigger brain signaling so rapidly.

“The neuron is not building the ‘gun’ as it sits there on the membrane – it’s already there,” Brunger said.

The team speculates that several of the joined protein complexes may group together and simultaneously interact with the same vesicle to efficiently trigger neurotransmitter release, an exciting area for further studies.

“The structure of the SNARE-synaptotagmin-1 complex is a milestone that the field has awaited for a long time, and it sets the framework for a better understanding of the system,” said James Rothman, a professor at Yale University who discovered the SNARE proteins and shared the 2013 Nobel Prize in Physiology or Medicine.

Thomas C. Südhof, a professor at the Stanford School of Medicine and Howard Hughes Medical Institute investigator who shared that 2013 Nobel Prize with Rothman, discovered synaptotagmin-1 and showed that it plays an important role as a calcium sensor and calcium-dependent trigger for neurotransmitter release.

“The new structure has identified unanticipated interfaces between synaptotagmin-1 and the neuronal SNARE complex that change how we think about their interaction by revealing, in atomic detail, exactly where they bind together,” Südhof said. “This is a new concept that goes much beyond previous general models of how synaptotagmin-1 functions.”

Using Crystals, Robotics and X-rays to Advance Neuroscience

To study the joined protein structure, researchers in Brunger’s laboratory at the Stanford School of Medicine found a way to grow crystals of the complex. They used a robotic system developed at SSRL to study the crystals at SLAC’s LCLS, an X-ray laser that is one of the brightest sources of X-rays on the planet. SSRL and LCLS are DOE Office of Science User Facilities.

The researchers combined and analyzed hundreds of X-ray images from about 150 protein crystals to reveal the atomic-scale details of the joined structure.

SSRL’s Aina Cohen, who oversaw the development of the highly automated platform used for the neuroscience experiment, said, “This experiment was the first to use this robotic platform at LCLS to determine a previously unsolved structure of a large, challenging multi-protein complex.” The study was also supported by X-ray experiments at SSRL and at Argonne National Laboratory’s Advanced Photon Source.

“This is a good example of how advanced tools, instruments and X-ray methods are providing us new insights into what are truly complex mechanisms,” Cohen said.

Brunger said future studies will explore other protein interactions relevant to neurotransmitter release. “What we studied is only a subset,” he said. “There are many other factors interacting with this system and we want to know what these look like. This by no means is the end of the story.”

In addition to researchers at SLAC, Stanford University and the Stanford School of Medicine, other contributing scientists were from Lawrence Berkeley National Laboratory. The research was supported by the Howard Hughes Medical Institute; the National Institutes of Health (NIH); the DOE Office of Science; and the SSRL Structural Molecular Biology Program, which is also supported by the DOE Office of Science and the NIH’s National Institute of General Medical Sciences.
https://www.nanotechnologyworld.org/…/Scientists-Discover-A…

What Colors Birds do See

What Colors Birds See

Birds see more colors than humans in several ways. Not only are birds able to perceive familiar colors as well as parts of the ultraviolet spectrum that are invisible to human eyes, but they also have better visual acuity to determine subtle differences between similar shades of color, gradations that humans are not able to discern.

The cells in the eye responsible for color detection – cones – are positioned in the retina, and birds have four types of cones rather than the three humans have. The exact number of cones varies in each bird species but is typically higher than humans and other mammals.

Diurnal birds that are active during the day have the best color sense. Perceiving different colors is less crucial for nocturnal birds, and many birds that are most active at night have a greater number of rod cells in their eyes instead, which allows them to capture more light and see better in low light conditions, though they may not see colors as clearly.

Why UV Light Matters
Being able to see UV light is a crucial aspect of how birds see color. For decades, ornithologists assumed that birds saw colors the same as humans, and many aspects of bird behavior were not able to be explained until birds' sensitivity to UV light was realized.

The ability to see ultraviolet light changes the perception birds have of many objects, even though humans may not see those differences.

Food: Some berries and other fruits have waxy coatings that reflect UV light, making them stand out vibrantly against green foliage. Birds can see the fruit much more clearly, making foraging much easier. Some insects also reflect UV light, and certain flowers will as well, giving birds a distinct advantage for finding those food sources.

Prey: Raptors use UV light to track prey, since the urine splashes and trails that voles, mice and other rodents use to mark their territory are brilliantly visible in ultraviolet light. This allows raptors to determine exactly where prey is located for more efficient hunting, even when the prey may not be visible itself.

Plumage: Species that may not appear dimorphic to humans may actually look very different in UV light. Male blue tits, for example, have a prominent crown seen under UV light, though the genders look similar to humans. Birds have no difficulty telling the difference, and can use those UV markings to help select mates, defend a territory or tell individual birds apart.

Eggs: Some brood parasite eggs, despite having similar visible colors and markings, look very different from host bird eggs under UV light, giving birds the ability to tell when an egg is not their own and allowing them to reject the interloper. While not all species that host brood parasites will reject unwanted eggs, the UV pattern may be a factor for those that do.

Wavelength Filtering

Not only can birds see ultraviolet light, but they see visible colors more distinctly than humans can. Each cone in a bird's eye has a drop of oil in it that selectively filters out certain colors, giving birds greater sensitivity to different color shades.

This allows birds to more easily see contrasts in their surroundings, perhaps seeing through the camouflage of prey or other birds, for example. This type of filtering or polarization is also useful for pelagic birds, allowing them to see deeper into the water than previously believed, which can help them find suitable food sources and prey.

The inside of a proton endures more pressure than anything else we’ve seen

Cecile G. Tamura

The proton, one of the components of atomic nuclei, is composed of fundamental particles called quarks and gluons. Gluons are the carriers of the force that binds quarks together, and free quarks are never found in isolation—that is, they are confined within the composite particles in which they reside. The origin of quark confinement is one of the most important questions in modern particle and nuclear physics because confinement is at the core of what makes the proton a stable particle and thus provides stability to the Universe. The internal quark structure of the proton is revealed by deeply virtual Compton scattering, a process in which electrons are scattered off quarks inside the protons, which  subsequently emit high-energy photons, which are detected in coincidence with the scattered electrons and recoil protons. Here we report a measurement of the pressure distribution experienced by the quarks in the proton. We find a strong repulsive pressure near the centre of the proton (up to 0.6 femtometres) and a binding pressure at greater distances. The average peak pressure near the centre is about 10³⁵ pascals, which exceeds the pressure estimated for the most densely packed known objects in the Universe, neutron stars³. This work opens up a new area of research on the fundamental gravitational properties of protons, neutrons and nuclei, which can provide access to their physical radii, the internal shear forces acting on the quarks and their pressure distributions.For the first time, scientists used experimental data to estimate the pressure inside a proton.

Protons break the pressure record set by neutron stars, the incredibly dense dead stars that can form when a massive star explodes and its core collapses, squeezing more mass than the sun’s into a remnant the size of a city. The pressure in the proton’s center averages a million trillion trillion times the strength of Earth’s atmospheric pressure.

"A neutron star is a city-size celestial object, with a mass 1.4 times our sun's. They were once massive stars that ended in supernova, then collapsed into a small, dense core. These are the densest object in the universe, and a proton’s internal force is even stronger than that! Previously, scientists surmised a proton may contain intense pressure. Yet, this is the first time it’s been proven."

Protons are made up of smaller particles including quarks, which are electrically charged, and gluons, which transmit the strong nuclear force that holds protons together.

In the center of this ball of particles, Burkert and colleagues report, an intense pressure pushes outward. But this record-breaking outward force is kept in check by an inward pressure from the outer regions of the particle.

This pressure pattern parallels what happens in much larger objects: “In some sense, it’s looking like a star,” says physicist Oleg Teryaev of the Joint Institute for Nuclear Research in Dubna, Russia. Stars also have pressures that push outward in their centers, which counteract the inward pull of gravity.

We seem to forget that these forces are going on inside of us all the time, too.

Corona Discharge vs. UV Ozone Generation

Ultraviolet (UV) ozone generation Ultraviolet lamps have been used for decades to generate ozone.  This lamp emits UV light at 185 nanometers (nm). Light is measured on a scale called an electromagnetic spectrum and its increments are referred to as nanometers. Figure 1 represents an electromagnetic scale; note the location of higher-frequency ultraviolet light relative to visible light (the range of light perceptible by the human eye). Figure 1 Wavelengths in nm Air (usually ambient) is passed over an ultraviolet lamp, which splits oxygen (O2) molecules in the gas. The resulting oxygen atoms (O-), seeking stability, attach to other oxygen molecules (O2), forming ozone (O3). The ozone is injected into the water, or air stream, where it inactivates contaminants by actually rupturing the organisms’ cell wall.  Corona Discharge (CD) ozone generation The technologies involved in corona discharge ozone generation are varied, but all operate fundamentally by passing dried, oxygen-containing gas through an electrical field. The electrical current causes the “split” in the oxygen molecules as described in the section on ultraviolet ozone generation. Past this common feature the variations are many, but the generally accepted technologies can be divided into three types - low frequency (50 to 100 Hz), medium frequency (100 to 1,000 Hz), and high frequency (1,000 + Hz). Since 85% to 95% of the electrical energy supplied to a corona discharge ozone generator produces heat, some method for heat removal is required. Also, proper cooling significantly affects the energy efficiency of the ozone generator, so most corona discharge systems utilize one or more of the following cooling methods: Air or water. Ozone Being created via Corona Discharge. At the heart of a corona discharge ozone system is the dielectric. The electrical charge is diffused over this dielectric surface, creating an electrical field, or “corona”. Critical to CD ozone systems is proper air preparation. The gas feeding the ozone generator must be very dry (minimum -80 degrees F), because the presence of moisture affects ozone production and leads to the formation of nitric acid. Nitric acid is very corrosive to critical internal parts of a CD ozone generator, which can cause premature failure and will significantly increase the frequency of maintenance.  The chart below shows that relative ozone output decreases as moisture content increases. Of the ozone technologies mentioned above, none has a clear advantage. However, to help narrow the field for a particular application, consider the amount of ozone required. You may find that low and medium frequency ozone systems will have prohibitively high initial costs for applications requiring less than ten lbs./day. However, they have a proven history of durability and reliability. High frequency ozone generators seem to have the best combination of cost efficiency and reliability for applications requiring less than ten lbs/day of ozone output. Advantages of Corona Discharge ozone generation Corona discharge ozone generators can use oxygen preparation thereby doubling the ozone output per given volume vs. dry air Small construction allowing generator to be installed in virtually any area Can create a more pure form of ozone without creating other harmful or irritating gases if using dry air or oxygen as a feed gas Corona cell life can exceed ten years Can create high quantities of ozone (up to 100-lbs/day) Can be more cost-effective than UV-ozone generation   Disadvantages of UV ozone generation Maximum ozone production rate is two grams/hr per UV bulb - depending on size Highest concentration of ozone that can be produced by 185-nm UV lamp is 0.2 percent by weight, approximately 10% of the average concentration available by corona discharge Considerable more electrical energy is required to produce a given quantity of ozone by UV radiation than by corona discharge Lower gas phase concentrations of ozone generated by UV radiation translate into the handling of much higher gas volumes than with CD-generated ozone UV lamps solarize over time, requiring periodic replacement

http://www.ozoneapplications.com/info/cd_vs_uv.htm

Engineers created a battery-less mobile phone that harvests energy from radio signals and light.

How Most Antimatter Forms in Milky Way

A team of international astrophysicists led by ANU has shown how most of the antimatter in the Milky Way forms.

Antimatter is material composed of the antiparticle partners of ordinary matter -- when antimatter meets with matter, they quickly annihilate each other to form a burst of energy in the form of gamma-rays.

Scientists have known since the early 1970s that the inner parts of the Milky Way galaxy are a strong source of gamma-rays, indicating the existence of antimatter, but there had been no settled view on where the antimatter came from.

ANU researcher Dr Roland Crocker said the team had shown that the cause was a series of weak supernova explosions over millions of years, each created by the convergence of two white dwarfs which are ultra-compact remnants of stars no larger than two suns.

"Our research provides new insight into a part of the Milky Way where we find some of the oldest stars in our galaxy," said Dr Crocker from the ANU Research School of Astronomy and Astrophysics.

Dr Crocker said the team had ruled out the supermassive black hole at the centre of the Milky Way and the still-mysterious dark matter as being the sources of the antimatter.

He said the antimatter came from a system where two white dwarfs form a binary system and collide with each other. The smaller of the binary stars loses mass to the larger star and ends its life as a helium white dwarf, while the larger star ends as a carbon-oxygen white dwarf.

"The binary system is granted one final moment of extreme drama: as the white dwarfs orbit each other, the system loses energy to gravitational waves causing them to spiral closer and closer to each other," Dr Crocker said.

He said once they became too close the carbon-oxygen white dwarf ripped apart the companion star whose helium quickly formed a dense shell covering the bigger star, quickly leading to a thermonuclear supernova that was the source of the antimatter.

Story Source:

Materials provided by Australian National University.

Image : Artist's concept of the Milky Way Galaxy. GLAST will provide detailed information on where stars are forming.

Credit: NASA JPL

Cecile G. Tamura

Gravitational waves slow the spin of shape-shifting neutron star

Cecile G. Tamura

Put on the brakes. A spinning neutron star that shifts between two states slows at a faster rate in one of them – and gravitational waves may be responsible.

The neutron star J1023+0038 spins almost 600 times per second. But as its powerful magnetic field dissipates energy, it is slowing by about 76 rotations per second every billion years. This magnetic “spin-down” is normal, but sometimes J1023 slows at a faster rate.
The different rates are associated with two states the neutron star switches back and forth between: one where it emits mostly radio waves and one where it mainly gives off X-rays. No one knows why some neutron stars behave in this way. But when the star is emitting mostly X-rays, it slows down about 30 per cent faster.

In this X-ray phase, the star is stealing material from a smaller companion star that orbits it. Brynmor Haskell at the Polish Academy of Sciences in Warsaw and Alessandro Patruno at Leiden University, the Netherlands, argue that this stolen gas may be the key to J1023’s strange spin.

As material snatched from its companion sticks to J1023’s surface, it builds a so-called mountain. Despite being no more than a few millimetres in height, the bump crushes the atoms beneath it, pushing them deeper into the neutron star. There the higher pressure fuses them into heavier elements, giving the mountain roots in the star’s interior.

The extra surface bump and the heavier atoms below it together result in the mountain creating an asymmetry in J1023’s gravity. “Neutron stars are very compact, roughly the mass of the sun compressed in a 10-kilometre radius,” says Haskell. “This means that even very small deformations can lead to large changes in the gravitational field.”

Riding the waves

The imbalance in the neutron star’s gravitational field may cause it to radiate gravitational waves, ripples in space-time caused by the movement of massive objects. These waves would carry away some of the energy that keeps J1023 spinning.

When the star switches from its X-ray phase to its radio phase, it stops munching on its stellar partner. As a result, the mountain gradually flattens out and the star emits no more spin-stunting gravitational waves.

Last year, the LIGO collaboration announced that it had observed gravitational waves shaken off by black holes colliding. But nobody has yet seen gravitational waves from continuous, rather than catastrophic, events. Objects like J1023 are promising candidates for future gravitational wave searches, especially if they can grow larger mountains.

“If this happens, then there might be many other neutron stars that do the same,” says Patruno. “Continuous gravitational waves might really be a widespread phenomenon.”

Such a scenario could also explain the apparent cap on neutron stars’ spin. “The fastest ones we see don’t rotate as fast as we think they should be able to go,” says Nils Andersson at the University of Southampton, UK. “There’s something missing in our understanding.”

If faster-spinning stars have defects such as mountains, they would emit more gravitational waves and slow down faster, setting a cosmic speed limit for neutron stars.

https://arxiv.org/abs/1703.08374

https://www.newscientist.com/…/dn9730-neutron-star-clocked…/

http://onlinelibrary.wiley.com/jour…/10.1111/(ISSN)1365-2966

https://www.newscientist.com/…/dn9428-massive-neutron-star…/

https://www.newscientist.com/…/2077162-revolution-in-physi…/

Jet Train from the 1970s

The first experiments to create a high-speed models of locomotives in the Soviet Union began in the 1930s. In 1934, at the Kolomna plant carried out preliminary designs of high-speed trains.The Russians want to copy the USA’s first Jet Train.

Don Wetzel, an engineer for the New York Central Railroad, was given the task in the mid-1960s of trying to make trains safer, less expensive and faster. 

His solution: strap two jet engines to the roof of a locomotive and see what happens.

What happened was Wetzel created the first jet-powered train that even to this day is the fastest locomotive in America.

A turbojet train is a train powered by turbojet engines. Like a jet aircraft, but unlike a gas turbine locomotive, the train is propelled by the jet thrust of the engines, rather than by its wheels. Only a handful of jet-powered trains have been built, for experimental research in high-speed rail. Turbojet engines have been built with the engine incorporated into a railcar combining both propulsion and passenger accommodation rather than as separate locomotives hauling passenger coaches.

Turbojet engines are most efficient at high speeds and so they have been applied to high-speed passenger services, rather than freight.

Some time ago we had a few photos of a piece of technology called “Soviet Turbojet Train”.   The projected speed for this out-of-the-sixties monster was planned to be up to 360 km/h, and it set a record of 250 km/h on the Soviet standard railway. The project was discarded afterwards, partly due to the very high fuel consumption of the jet engines compared to the engines of jet planes, and we thought the only train built was lost, but recently these guys discovered it rusting on the back ways of some railroad.

The first attempt to use turbojet engines on a railroad was made by the New York Central Railroad in 1966. Their railcar M-497 was able to reach speeds up to 184 miles per hour (296 km/h) – we will cover that next week

The Russian train maker Kalininsky formed the Speed Wagon Laboratory. Following the New Yorker’s example, the modified the chassis of one of their ER22 head engines to look more or less like a rough version of a Shinkansen, the Japanese bullet train which was already working in 1964 at 130 mph (210km/h).

They added two turbojet engines on the front as well: two turbojets from a Yakovlev YAK-40. Their first test was in 1971 on the line joining Golutvin with Ozery. They achieved a low 116mph (187km/h). However, they kept increasing the speed until they got up to 154mph (249km/h).

Like it’s American counterpart it never really went any further than that. Jet fuel costs, noise levels, and probably just the fact that this is plane old silly contributed to the closing of the programs in both countries..

The Biography of the E = mc2 ( World's Most Famous Equation)

Albert Einstein's name will forever be linked with the famous equation E=mc2 equating mass with energy. It is perhaps one of the most quoted and widely seen physics equations in the public domain.Yet contained in this short and concise equation is the heritage and ultimate destiny of our species. This equation expresses succinctly the process by which all the matter found in stars, planets, galaxies and people came into being. This equation expresses the very essence of cosmic history in a very brief and yet poetic phrase. For contained in this equation is the very essence of cosmic history and how in the span of fourteen billion years energy evolved into matter and matter evolved into life and consciousness. It explains how within the first three minutes of the big bang pure energy condensed into matter and later how, through the process of nuclear fusion, heavy elements were forged in the hearts of distant and massive suns. It’s the existence of these elements that make the existence of living things a possibility. Porpoises, petunias and people owe there existence to the laws of physics expressed and revealed within the expression E=mc2.Today on Far Future Horizons we explore the historical and scientific antecedents of Einstein's work and meet the other men and women whose work helped lead to the Theory of Special Relativity.Also add the book E = mc2: A Biography of the World's Most Famous Equation by David Bodanis to your weekend reading list.farfuturehorizons.blogspot.com

Harvard scientists just turned hydrogen into metal

More than 80 years after it was first predicted scientists at Harvard turned hydrogen into metal, and it could revolutionize our planet.

They did it by subjecting hydrogen to extremely high pressures, which changed it from a liquid to a solid.

The resulting material could be used as a superconductor, which would work at room temperature.

This would save lots of energy and money because current superconductors only work at below -269°C.

It could also be used to make MRI scanners and power lines cheaper and more efficient too.

In 1935, scientists predicted that the element hydrogen could become a metal if subjected to enough pressure. Teams have been attempting to confirm the prediction ever since, but have not been able to construct a vise capable of squeezing the element enough without breaking the equipment.

But a team of scientists at Harvard University published a paper this week in the peer-reviewed journal Science saying they managed to squeeze hydrogen in a diamond vise to the point that the element became reflective, a key property of metals.

The study is not merely a parlor trick. Metallic hydrogen is thought to be a superconductor, meaning it could conduct electricity without any resistance. Electricity traveling through normal circuits loses energy to resistance over time, often in the form of heat. This is why it is harder to send electrical currents (say, through the electricity grid) over long distances than short ones. But a current traveling through a superconducting material loses nearly zero energy.

Superconductive metals are used to make the magnets for devices such as hospital MRI machines and particle accelerators such as CERN. The trouble with many superconductors is that the materials now used need to be cooled to extremely low temperatures in order to work, which is expensive.

It is also possible that metallic hydrogen material may be "metastable," according to Science Magazine. This means that, once formed, it may retain its metallic properties even at normal temperatures and pressure levels, like diamonds. If so, it could conduct electricity at nearly 100 percent efficiency in normal conditions. Again, this could dramatically reduce the costs of transferring electrical currents, meaning more powerful and efficient electric motors, and a far more efficient electrical grid.

Scientists have been searching for such a material almost as long as they have known about superconductivity.

Of course, the study has its critics. Eugene Gregoryanz, a physicist at the University of Edinburgh, told Science Magazine he sees a several problems with the experiment's procedures.

"The word garbage cannot really describe it," said Gregoryanz, of the experiment.

The video below, from Harvard, discusses the discovery in detail: