Flash Physics: Intricate crystals made with DNA, laser harnesses Josephson effect, borophene has Dirac cones

Golden design: DNA glues gold nanoparticles into clathrate crystals structure

The most complex synthetic nanoparticle crystal ever made has been created using DNA and gold. Researchers have used gold nanoparticles and DNA "smart glue" to assemble intricate clathrate-crystal structures. There are many aspects of nature that scientists struggle to emulate in a laboratory. This includes a huge array of complex crystal structures such as clathrates. These cage-like lattices comprise polyhedral clusters and pores that can house small molecules. Such structures are useful for environmental applications where pollutants can be held within the pores.

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Flash Physics: Too radioactive even for robots, IBM to build 50 qubit computer, seeing through opaque materials

Failing robots: radiation levels inside Fukushima units too high even for robots

Better robots are needed for investigating the Fukushima Daiichi nuclear plant after current designs failed due to radiation levels and debris obstacles. At a recent news conference, president of Fukushima Daiichi decommissioning, Naohiro Masuda, spoke about the need for more creative robot design after repeated failures. In 2011, multiple reactors at the Fukushima nuclear plant went into meltdown after a severe earthquake and tsunami. To safely decommission the damaged plant, its operator Tokyo Electric Power Company (TEPCO) must know exactly where the melted fuel is and the extent of structural damage to the surrounding buildings. The radiation levels, however, would kill a human within seconds, so TEPCO is reliant upon remote-controlled robotic probes. Yet early robots have come across unexpected challenges. In February, TEPCO sent in two

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Complex ultrasound signals created by light

Light and sound: how to make an ultrasound "7"

A new way of creating specially shaped pulses of ultrasound using light and a 3D printer has been unveiled by Michael Brown and colleagues at University College London. The pulses, which are creating using the photoacoustic effect in a 3D-printed material, could be tailored to perform a range of tasks including manipulating biological cells and delivering drugs to specific parts of the body.

Renowned for its ability to let us see inside the body, ultrasound refers to acoustic waves at frequencies above about 20 kHz. Such waves can also be used for medical treatment, industrial product imaging and chemistry. Researchers have also recently developed acoustic tractor beams and tweezers for the non-contact manipulation of small objects.

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Meet the 'angulon', a new quasiparticle found in superfluid helium

Molecule traps: angulons spotted in helium droplets

The quasiparticle concept allows physicists to describe complex, many-body interactions in terms of the behaviour of a single particle-like entity. Usually these particles turn up in condensed-matter systems such as semiconductors, but a new type of quasiparticle known as an angulon has been proposed to describe the rotation of an atomic or molecular impurity within a solvent. First proposed theoretically two years ago, angulons have now been shown to explain the curious behaviour of a range of different molecules rotating within liquid helium.

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Physics: Lensing study backs cold dark matter, cancer detected by Raman spectroscopy, black-hole burbs

New gravitational lensing study backs cold dark matter

Cold and dark: map of dark matter in one of the galaxy clusters

A new high-resolution map of dark matter – an invisible substance that appears to have a profound gravitational effect on galaxies and other large-scale structures in the cosmos – has been produced by an international team of astronomers using the Hubble Space Telescope. The map focuses on three galaxy clusters that act as cosmic telescopes by magnifying images of the more distant universe through gravitational lensing. The degree to which this magnification occurs gives an extremely precise measurement of the dark matter within the clusters. "We have mapped all of the clumps of dark matter that the data permit us to detect, and have produced the most detailed topological map of the dark-matter landscape to date," explains Priyamvada Natarajan of Yale University in the US,

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Insects inspire water-repellent material

Surfaces inspired by cicada wings and mosquito eyes have antifogging properties. A team of scientists from France and the US has created surfaces that mimic these natural systems, in an attempt to replicate their anti-fogging mechanisms.
When water comes into contact with a surface, its behaviour can vary from beading into tiny droplets to spreading evenly over the surface. For water-loving, hydrophilic materials, the droplet will spread out and maximize contact with the surface. In contrast, for water-repelling, hydrophobic materials, the water forms beads. This behaviour is due to the angle between the droplet's edge and the surface directly underneath – known as the contact angle. When the contact angle is more than 90°, the surface is considered hydrophobic. If it is higher than 160°,

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Earth’s mantle may be hotter than thought

HOT STUFF  Temperatures in Earth’s mantle are higher than previously thought, results from a new experiment suggest.

Temperatures across Earth’s mantle are about 60 degrees Celsius higher than previously thought, a new experiment suggests. Such toasty temperatures would make the mantle runnier than earlier research suggested, a development that could help explain the details of how tectonic plates glide on top of the mantle, geophysicists report in the March 3 Science.

“Scientists have been arguing over the mantle temperature for decades,” says study coauthor Emily Sarafian, a geophysicist at the Woods Hole Oceanographic Institution in Massachusetts and at MIT. “Scientists will argue over 10 degree changes, so changing it by 60 degrees is

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Oldest microfossils suggest life thrived on Earth about 4 billion years ago

Tiny, iron-rich fossils exhumed from the depths of an ancient ocean could reveal the cradle of life.

These micrometer-scale structures are probably remnants of microorganisms that once lived amidst ancient hydrothermal vents, researchers suggest March 1 in Nature.

“In a nutshell, what we’ve found are the oldest microfossils on Earth,” says study coauthor Matthew Dodd, a biogeochemist at University College London. The rocks that hold the fossils came from Quebec and date to somewhere between 4.28 billion and 3.77 billion years old — when Earth was still a baby. The next oldest microfossils reported are just under 3.5 billion years

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FLASH; Frogs see colour at night, new lens sharpens X-rays, PICO-60 puts new limits on dark-matter

    Amphibians have colourful night-time vision

Froggy vision: behavioural tests show amphibians see colour in the dark

Frogs and toads can see colour when it is too dark for humans to see. Many animals have evolved to have impressive visual skills, yet understanding how and what they see has always been a challenge for scientists. A group from Lund University in Sweden and the University of Helsinki in Finland has therefore used behavioural studies to investigate the vision of frogs. Human eyes contain two types of visual cells in the retina – cones and rods. The cones allow us to see colour, but they stop working at night because they require a lot of light. At this point the rods take over and enable us to see in black and white under low-light conditions. Although this is the case for most vertebrates, frogs and toads are unique in that they have two spectrally different kinds of

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Flash Physics: Flower acts as supercapacitor, ORNL head steps down, triboelectricity boosts mass spectrometer

Flower doubles as supercapacitor

Flower power: the rose supercapacitor

Two years ago, researchers at Linköping University in Sweden showed that a rose can form the basis of a transistor. Now team member Roger Gabrielsson and colleagues have used a similar flower to create a supercapacitor that can store a large amount of electrical energy. The team put a cut rose into a polymer solution, which was absorbed by the flower. The material polymerizes spontaneously within the stem, leaves and petals of the flower to create long threads that conduct electricity. This allows a large amount of electrical change to be pumped into the flower. "We have been able to charge the rose repeatedly, for hundreds of times without any loss

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Climate-friendly aircraft routing could cut environmental damage

Changing direction: rerouting could reduce environmental impact caption

Rerouting transatlantic flights to follow the most climate-friendly path could damage the climate 10% less for an increase in costs of just 1%. That's according to a team from Germany, the Netherlands, Belgium, Norway and the UK.

"An attractive aspect of our approach is that it potentially enables some mitigation of aviation's climate impact...using the current aircraft fleet," Volker Grewe of the Deutsches Zentrum für Luft- und Raumfahrt, Germany, and Delft University of Technology in the Netherlands, explains. "Some mitigation options involve changes in aircraft or engine design, which would take decades to implement given the slow – and expensive – turnover of the global fleet."

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Supernova 1987A enters a new phase

Moving on: SN 1987A is entering a new era

Thirty years after it exploded, supernova SN 1987A is starting a new phase in its development as the shock wave from the stellar explosion is finally passing beyond a ring of gas encircling the dead star.

On 23 February 1987, a blue supergiant star named Sanduleak –69° 202 exploded in the Large Magellanic Cloud, which is a dwarf-galaxy neighbour to the Milky Way 169,000 light-years away. Named SN 1987A, it was the first supernova since 1604 to be visible to the naked eye.

Robert Kirshner, an astrophysicist at the Harvard–Smithsonian Center for Astrophysics in

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