Nature is the international weekly journal of science: a magazine style journal that publishes full-length research papers in all disciplines of science, as well as News and Views, reviews, news, features, commentaries, web focuses and more, covering all branches of science and how science impacts upon all aspects of society and life.
A coral-reef fish can match its scent to the odour of the surrounding reef, masking itself from predators.Harlequin filefish (Oxymonacanthus longirostris; pictured) live around reefs in the Pacific and Indian oceans and feed on particular species of coral. A team led by
Geoscientists have found possible evidence of two typhoons that, according to Japanese legend, wiped out invading Mongol fleets in the years 1274 and 1281.Jon Woodruff of the University of Massachusetts, Amherst, and his colleagues collected a 2,000-year-old sediment record from a coastal lake on
Hail storms can cause billions of dollars' worth of damage, but until now scientists have known little about the precise mass and shape of hail. A study has found that hailstones that are not perfectly spherical can sometimes travel faster and hit objects with greater
A study of primate and bacterial proteins involved in capturing iron from the blood has revealed an evolutionary arms race in the battle over this important nutrient.Matthew Barber and Nels Elde at the University of Utah in Salt Lake City focused on transferrin, a
One of the major Maya cities thrived in a tropical forest by using sophisticated agricultural, forestry and water-management techniques.David Lentz at the University of Cincinnati in Ohio and his colleagues surveyed modern forests at the site of Tikal in Guatemala, which was a bustling
Physicists have used lasers to increase the amount of energy that electrons gain per metre by more than two orders of magnitude compared with traditional accelerators.Conventional colliders can accelerate particles to much greater energies, but over many kilometres. Wim Leemans at Lawrence Berkeley National
Ibuprofen can be produced in minutes by mixing reagents as they flow through a series of connecting tubes.Synthesizing a substance in a continuous-flow process offers more control over reactions and allows less solvent to be used than batch production in flasks. But solid by-products
An insecticide banned in some areas for its effect on bees not only fails to kill certain pests, but also harms the predators that feed on them.Neonicotinoid insecticides are used on many crops, including soya-bean plants, on which pest slugs (Deroceras reticulatum)
Using a modest-sized ground-based telescope, astronomers have spotted a planet twice the size of Earth passing in front of its host star.Researchers typically study planets outside the Solar System using space telescopes or much larger telescopes on Earth, but studies with space telescopes are
The landing of the Philae probe on comet 67P/Churyumov–Gerasimenko last month has led to speculation that comets might have delivered the building-block elements of life to Earth — an idea anticipated by the French astronomer Camille Flammarion more than a century ago in his 1880
Protected conservation areas face huge challenges globally (see J. E. M.Watsonet al. Nature515, 67–73;10.1038/515067a2014). But examples that are effectively funded and managed can be found in Namibia and in the Brazilian Amazon. In our
On 1 January 2015, a large new government office will take over Hungary's research-grant agency for basic science, OTKA. This will assume all budget management for research, development and innovation — destroying what the European Science Foundation has described as the agency's “high degree of
Conventional methods of flood protection such as levees are no longer adequate against the increased risk of flooding in Asian delta cities. We call for a multipronged approach that focuses on long-term, sustainable solutions to increase these cities' resilience to flooding (see also L.Giosan
One solution to the challenges posed by voluntary peer review (M.ArnsNature515, 46710.1038/515467a (2014) and see Nature515, 480–482;10.1038/515480a2014) might be to create a professional, independent body of reviewers
An iron catalyst has been developed that mediates bond formation between a wide range of alkene reactants, opening up short synthetic routes to compounds that were previously accessible only through arduous pathways. See Article p.343
The development of RNA-based devices called toehold switches that regulate translation might usher in an era in which protein production can be linked to almost any RNA input and provide precise, low-cost diagnostics.
50 Years AgoDr. H. J. Kingsley and Dr. J. E. A. David of Bulawayo have described ... the case of a girl aged 22 months ... She appeared to be completely insensitive to pain ... She was admitted to hospital for investigation and was
New analysis reveals the conservation gains that could be achieved by expanding the global network of protected areas — but also how this may be undermined by land-use change and a lack of international coordination. See Letter p.383
Magnetoelectric materials allow magnetism to be controlled by an electric field. The discovery of an indirect path for switching electrical polarization in one such material brings this idea close to practical use. See Letter p.370
Crystal structures of the complete RNA polymerases from influenza A and B viruses provide insight into how these enzymes initiate RNA synthesis, and reveal targets for antiviral drug design. See Articles p.355 & p.361
Carbon–carbon (C–C) bonds form the backbone of many important molecules, including polymers, dyes and pharmaceutical agents. The development of new methods to create these essential connections in a rapid and practical fashion has been the focus of numerous organic chemists. This endeavour relies heavily on
Naturally occurring variations of Polycomb repressive complex 1 (PRC1) comprise a core assembly of Polycomb group proteins and additional factors that include, surprisingly, autism susceptibility candidate 2 (AUTS2). Although AUTS2 is often disrupted in patients with neuronal disorders, the mechanism underlying the pathogenesis is
The influenza virus polymerase transcribes or replicates the segmented RNA genome (viral RNA) into viral messenger RNA or full-length copies. To initiate RNA synthesis, the polymerase binds to the conserved 3′ and 5′ extremities of the viral RNA. Here we present the crystal structure of
Influenza virus polymerase uses a capped primer, derived by ‘cap-snatching’ from host pre-messenger RNA, to transcribe its RNA genome into mRNA and a stuttering mechanism to generate the poly(A) tail. By contrast, genome replication is unprimed and generates exact full-length copies of the template. Here
Stars spend most of their lifetimes on the main sequence in the Hertzsprung–Russell diagram. The extended main-sequence turn-off regions—containing stars leaving the main sequence after having spent all of the hydrogen in their cores—found in massive (more than a few tens of thousands of solar masses), intermediate-age (about one to three billion years old) star clusters are usually interpreted as evidence of internal age spreads of more than 300 million years, although young clusters are thought to quickly lose any remaining star-forming fuel following a period of rapid gas expulsion on timescales of order 107 years. Here we report, on the basis of a combination of high-resolution imaging observations and theoretical modelling, that the stars beyond the main sequence in the two-billion-year-old cluster NGC 1651, characterized by a mass of about 1.7 × 105 solar masses, can be explained only by a single-age stellar population, even though the cluster has a clearly extended main-sequence turn-off region. The most plausible explanation for the existence of such extended regions invokes a population of rapidly rotating stars, although the secondary effects of the prolonged stellar lifetimes associated with such a stellar population mixture are as yet poorly understood. From preliminary analysis of previously obtained data, we find that similar morphologies are apparent in the Hertzsprung–Russell diagrams of at least five additional intermediate-age star clusters, suggesting that an extended main-sequence turn-off region does not necessarily imply the presence of a significant internal age dispersion.
The technological appeal of multiferroics is the ability to control magnetism with electric field. For devices to be useful, such control must be achieved at room temperature. The only single-phase multiferroic material exhibiting unambiguous magnetoelectric coupling at room temperature is BiFeO3 (refs 4 and 5). Its weak ferromagnetism arises from the canting of the antiferromagnetically aligned spins by the Dzyaloshinskii–Moriya (DM) interaction. Prior theory considered the symmetry of the thermodynamic ground state and concluded that direct 180-degree switching of the DM vector by the ferroelectric polarization was forbidden. Instead, we examined the kinetics of the switching process, something not considered previously in theoretical work. Here we show a deterministic reversal of the DM vector and canted moment using an electric field at room temperature. First-principles calculations reveal that the switching kinetics favours a two-step switching process. In each step the DM vector and polarization are coupled and 180-degree deterministic switching of magnetization hence becomes possible, in agreement with experimental observation. We exploit this switching to demonstrate energy-efficient control of a spin-valve device at room temperature. The energy per unit area required is approximately an order of magnitude less than that needed for spin-transfer torque switching. Given that the DM interaction is fundamental to single-phase multiferroics and magnetoelectrics, our results suggest ways to engineer magnetoelectric switching and tailor technologically pertinent functionality for nanometre-scale, low-energy-consumption, non-volatile magnetoelectronics.
The concerted motion of two or more bound electrons governs atomic and molecular non-equilibrium processes including chemical reactions, and hence there is much interest in developing a detailed understanding of such electron dynamics in the quantum regime. However, there is no exact solution for the quantum three-body problem, and as a result even the minimal system of two active electrons and a nucleus is analytically intractable. This makes experimental measurements of the dynamics of two bound and correlated electrons, as found in the helium atom, an attractive prospect. However, although the motion of single active electrons and holes has been observed with attosecond time resolution, comparable experiments on two-electron motion have so far remained out of reach. Here we show that a correlated two-electron wave packet can be reconstructed from a 1.2-femtosecond quantum beat among low-lying doubly excited states in helium. The beat appears in attosecond transient-absorption spectra measured with unprecedentedly high spectral resolution and in the presence of an intensity-tunable visible laser field. We tune the coupling between the two low-lying quantum states by adjusting the visible laser intensity, and use the Fano resonance as a phase-sensitive quantum interferometer to achieve coherent control of the two correlated electrons. Given the excellent agreement with large-scale quantum-mechanical calculations for the helium atom, we anticipate that multidimensional spectroscopy experiments of the type we report here will provide benchmark data for testing fundamental few-body quantum dynamics theory in more complex systems. They might also provide a route to the site-specific measurement and control of metastable electronic transition states that are at the heart of fundamental chemical reactions.
Microbial ecosystems can be sustained by hydrogen gas (H2)-producing water–rock interactions in the Earth’s subsurface and at deep ocean vents. Current estimates of global H2 production from the marine lithosphere by water–rock reactions (hydration) are in the range of 1011 moles per year. Recent explorations of saline fracture waters in the Precambrian continental subsurface have identified environments as rich in H2 as hydrothermal vents and seafloor-spreading centres and have suggested a link between dissolved H2 and the radiolytic dissociation of water. However, extrapolation of a regional H2 flux based on the deep gold mines of the Witwatersrand basin in South Africa yields a contribution of the Precambrian lithosphere to global H2 production that was thought to be negligible (0.009 × 1011 moles per year). Here we present a global compilation of published and new H2 concentration data obtained from Precambrian rocks and find that the H2 production potential of the Precambrian continental lithosphere has been underestimated. We suggest that this can be explained by a lack of consideration of additional H2-producing reactions, such as serpentinization, and the absence of appropriate scaling of H2 measurements from these environments to account for the fact that Precambrian crust represents over 70 per cent of global continental crust surface area. If H2 production via both radiolysis and hydration reactions is taken into account, our estimate of H2 production rates from the Precambrian continental lithosphere of 0.36–2.27 × 1011 moles per year is comparable to estimates from marine systems.
Protected areas are one of the main tools for halting the continuing global biodiversity crisis caused by habitat loss, fragmentation and other anthropogenic pressures. According to the Aichi Biodiversity Target 11 adopted by the Convention on Biological Diversity, the protected area network should be expanded to at least 17% of the terrestrial world by 2020 (http://www.cbd.int/sp/targets). To maximize conservation outcomes, it is crucial to identify the best expansion areas. Here we show that there is a very high potential to increase protection of ecoregions and vertebrate species by expanding the protected area network, but also identify considerable risk of ineffective outcomes due to land-use change and uncoordinated actions between countries. We use distribution data for 24,757 terrestrial vertebrates assessed under the International Union for the Conservation of Nature (IUCN) ‘red list of threatened species’, and terrestrial ecoregions (827), modified by land-use models for the present and 2040, and introduce techniques for global and balanced spatial conservation prioritization. First, we show that with a coordinated global protected area network expansion to 17% of terrestrial land, average protection of species ranges and ecoregions could triple. Second, if projected land-use change by 2040 (ref. 11) takes place, it becomes infeasible to reach the currently possible protection levels, and over 1,000 threatened species would lose more than 50% of their present effective ranges worldwide. Third, we demonstrate a major efficiency gap between national and global conservation priorities. Strong evidence is shown that further biodiversity loss is unavoidable unless international action is quickly taken to balance land-use and biodiversity conservation. The approach used here can serve as a framework for repeatable and quantitative assessment of efficiency, gaps and expansion of the global protected area network globally, regionally and nationally, considering current and projected land-use pressures.