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Categories: Engineering: Graphene, Paleontology: Early Mammals and Birds

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Chemists and engineers have discovered a fundamental friction law that is leading to a deeper understanding of energy dissipation in friction and the design of two-dimensional materials capable of minimizing energy loss.

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For a species of flycatcher in the remote Solomon Islands, scientists have so far found at least two genetic pathways leading to the same physical outcome: all-black feathers. This change was no random accident. It was a result of nature specifically selecting for this trait.

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Engineers synthesized aligned forests of nanoscale fibers made of boron nitride, or 'white graphene.' They hope to harness the technique to fabricate bulk-scale arrays of these nanotubes, which can then be combined with other materials to make stronger, more heat-resistant composites, for instance to shield space structures and hypersonic aircraft.

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Piecing together the crushed skull of a fossil bird that lived alongside the dinosaurs helped researchers extrapolate what its brain would have looked like: big olfactory bulbs would have meant that this bird, the earliest known animal to eat fruit, had a better sense of smell than most modern birds. And the bones around its eye sockets revealed that it would have been better at seeing by day than at night.

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Researchers have engineered a quantum box for polaritons in a 2D material, achieving large polariton densities and a partially 'coherent' quantum state. New insights from the novel technique could allow researchers to access striking 'collective' quantum phenomena in this material family, and enable ultra-energy efficient and high-performance future technologies. Laying a 'small' 2D material on top of a 'large' layer allowed the researchers to trap and investigate polaritons, comparing them with freely moving polaritons.

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Today, increasing levels of carbon dioxide in the atmosphere are warming up the planet. Climate change can disrupt the balance of ecosystems and contribute to endangerment and extinction of some species. New research suggests that a period of intense volcanism in the Central Andes may be the missing link in the story of past climate changes that led to the extinctions of ancient marine mammals.

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A giant kangaroo that once roamed on four legs through remote forests in the Papua New Guinea Highlands may have survived as recently as 20,000 years ago -- long after large-bodied megafauna on mainland Australia went extinct, new research indicates. Palaeontologists, archaeologists and geoscientists, have used new techniques to re-examine megafauna bones from the rich Nombe Rock Shelter fossil site in Chimbu Province in a bid to better understand the intriguing natural history of PNG.

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An international team has reconstructed the genome organization of the earliest common ancestor of all mammals. The reconstructed ancestral genome could help in understanding the evolution of mammals and in conservation of modern animals. The earliest mammal ancestor likely looked like the fossil animal 'Morganucodon' which lived about 200 million years ago.

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Researchers have demonstrated how a nanoscale layer of superconducting niobium nitride (NbNx) can be grown directly onto aluminum nitride (AIN). The arrangement of atoms, nitrogen content, and electrical conductivity were found to depend on growth conditions, particularly temperature, and the spacing of atoms in the two materials was sufficiently compatible to produce flat layers. The structural similarity between NbNx and AIN will facilitate the integration of superconductors into semiconductor optoelectronic devices.

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The carrier concentration and conductivity in p-type monovalent copper semiconductors can be significantly enhanced by adding alkali metal impurities. Doping with isovalent and larger-sized alkali metal ions effectively increased the free charge carrier concentration, and the mechanism was unraveled by their theoretical calculations. Their carrier doping technology enables high carrier concentration and high mobility p-type thin films to be prepared from the solution process, with photovoltaic device applications.

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Researchers demonstrated a topological insulator device that opens the way towards observing the quantum anomalous Hall effect. Because the currents generated are resistant to scattering, but very sensitive to applied magnetic fields, they may be used for reducing power consumption in computing applications.

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1 in 5 adult female white-necked jacobin hummingbirds look like males. New research shows that this is a rare case of 'deceptive mimicry' within a species: Females with male-like plumage are trying to pass themselves off as males, and as a result receive a benefit in the form of reduced aggression from males.

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Physicists have demonstrated a new magnetized state in a monolayer of tungsten ditelluride. This material of one-atom thickness has an insulating interior but a conducting edge, which has important implications for controlling electron flow in nanodevices.

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Did the first ancestors of whales pick up where the mosasaurs left off 66 million years ago, after the extinction of all the large predatory marine reptiles? A study has looked into the possible convergences in morphology and behavior that may exist between these two groups of large marine predatory animals.

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Approximately 13.5 million years ago, north-west Queensland was home to an unusual and particularly tiny species of crocodile and now scientists are unlocking its secrets.

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To investigate whether paleoclimatic temperature shifts are correlated with body size changes, biologists decided to test this hypothesis using tetraodontiform fishes as a model group.

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How do different materials react to the impact of ions? This is a question that plays an important role in many areas of research -- for example in nuclear fusion research, when the walls of the fusion reactor are bombarded by high-energy ions. However, it is difficult to understand the temporal sequence of such processes. A research group has now succeeded in analyzing on a time scale of one femtosecond what happens to the individual particles involved when an ion penetrates materials such as graphene or molybdenum disulphide.

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Researchers have used an atomically thin material to build a device that can change the color of laser beams. Their microscopic device -- a fraction of the size of conventional color converters -- may yield new kinds of ultra-small optical circuit chips and advance quantum optics.

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Superconductors are the key to lossless current flow. However, the realization of superconducting diodes has only recently become an important topic of fundamental research. An international research team has now succeeded in reaching a milestone: the demonstration of an extremely strong superconducting diode effect in a single two-dimensional superconductor.

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An international research team has detected novel quantum effects in high-precision studies of natural double-layer graphene. This research provides new insights into the interaction of the charge carriers and the different phases, and contributes to the understanding of the processes involved.