Nature

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.
  • Spontaneous transfer of chirality in an atropisomerically enriched two-axis system
    [Apr 2014]

    Spontaneous transfer of chirality in an atropisomerically enriched two-axis system

    Nature 509, 7498 (2014). doi:10.1038/nature13189

    Authors: Kimberly T. Barrett, Anthony J. Metrano, Paul R. Rablen & Scott J. Miller

    One of the most well-recognized stereogenic elements in a chiral molecule is an sp3-hybridized carbon atom that is connected to four different substituents. Axes of chirality can also exist about bonds with hindered barriers of rotation; molecules containing such axes are known as atropisomers. Understanding the dynamics of these systems can be useful, for example, in the design of single-atropisomer drugs or molecular switches and motors. For molecules that exhibit a single axis of chirality, rotation about that axis leads to racemization as the system reaches equilibrium. Here we report a two-axis system for which an enantioselective reaction produces four stereoisomers (two enantiomeric pairs): following a catalytic asymmetric transformation, we observe a kinetically controlled product distribution that is perturbed from the system’s equilibrium position. As the system undergoes isomerization, one of the diastereomeric pairs drifts spontaneously to a higher enantiomeric ratio. In a compensatory manner, the enantiomeric ratio of the other diastereomeric pair decreases. These observations are made for a class of unsymmetrical amides that exhibits two asymmetric axes—one axis is defined through a benzamide substructure, and the other axis is associated with differentially N,N-disubstituted amides. The stereodynamics of these substrates provides an opportunity to observe a curious interplay of kinetics and thermodynamics intrinsic to a system of stereoisomers that is constrained to a situation of partial equilibrium.

    Categories: Journal Articles
  • Coordination of entorhinal–hippocampal ensemble activity during associative learning
    [Apr 2014]

    Coordination of entorhinal–hippocampal ensemble activity during associative learning

    Nature 510, 7503 (2014). doi:10.1038/nature13162

    Authors: Kei M. Igarashi, Li Lu, Laura L. Colgin, May-Britt Moser & Edvard I. Moser

    Accumulating evidence points to cortical oscillations as a mechanism for mediating interactions among functionally specialized neurons in distributed brain circuits. A brain function that may use such interactions is declarative memory—that is, memory that can be consciously recalled, such as episodes and facts. Declarative memory is enabled by circuits in the entorhinal cortex that interface the hippocampus with the neocortex. During encoding and retrieval of declarative memories, entorhinal and hippocampal circuits are thought to interact via theta and gamma oscillations, which in awake rodents predominate frequency spectra in both regions. In favour of this idea, theta–gamma coupling has been observed between entorhinal cortex and hippocampus under steady-state conditions in well-trained rats; however, the relationship between interregional coupling and memory formation remains poorly understood. Here we show, by multisite recording at successive stages of associative learning, that the coherence of firing patterns in directly connected entorhinal–hippocampus circuits evolves as rats learn to use an odour cue to guide navigational behaviour, and that such coherence is invariably linked to the development of ensemble representations for unique trial outcomes in each area. Entorhinal–hippocampal coupling was observed specifically in the 20–40-hertz frequency band and specifically between the distal part of hippocampal area CA1 and the lateral part of entorhinal cortex, the subfields that receive the predominant olfactory input to the hippocampal region. Collectively, the results identify 20–40-hertz oscillations as a mechanism for synchronizing evolving representations in dispersed neural circuits during encoding and retrieval of olfactory–spatial associative memory.

    Categories: Journal Articles
  • The democracy carousel
    [Apr 2014]

    The democracy carousel

    Nature 508, 7496 (2014). doi:10.1038/508287a

    European law has allowed citizens to force a debate on human embryonic stem cells less than a year after the previous one. This fruitless democratic exercise has left scientists spinning in uncertainty.

    Categories: Journal Articles
  • Cancer crossroads
    [Apr 2014]

    Cancer crossroads

    Nature 508, 7496 (2014). doi:10.1038/508287b

    Efforts to understand cancer genomes should take on a fresh focus.

    Categories: Journal Articles
  • Practical nonsense
    [Apr 2014]

    Practical nonsense

    Nature 508, 7496 (2014). doi:10.1038/508288a

    Downgrading practical science will impede UK students in the global workplace

    Categories: Journal Articles
  • Beware of backroom deals in the name of 'science'
    [Apr 2014]

    Beware of backroom deals in the name of 'science'

    Nature 508, 7496 (2014). http://www.nature.com/doifinder/10.1038/508289a

    Author: Colin Macilwain

    The term 'sound science' has become Orwellian double-speak for various forms of pro-business spin, says Colin Macilwain.

    Categories: Journal Articles
  • Ecology: Fallen trees form a sea-floor feast
    [Apr 2014]

    Ecology: Fallen trees form a sea-floor feast

    Nature 508, 7496 (2014). doi:10.1038/508290a

    Dead trees at the bottom of the ocean host a diverse range of bacteria, fungi and molluscs (pictured; a cent is included for scale).Craig McClain of the National Evolutionary Synthesis Center in Durham, North Carolina, and James Barry of the Monterey Bay Aquarium Research

    Categories: Journal Articles
  • Photonics: Light goes one way on a chip
    [Apr 2014]

    Photonics: Light goes one way on a chip

    Nature 508, 7496 (2014). doi:10.1038/508290b

    A device that controls light so that it travels in just one direction could be used in high-speed computers that carry signals using light, rather than electric charges.A team led by Lan Yang and Şahin Kaya Özdemir at Washington University in St. Louis created

    Categories: Journal Articles
  • Evolution: Ancient lion DNA yields family tree
    [Apr 2014]

    Evolution: Ancient lion DNA yields family tree

    Nature 508, 7496 (2014). doi:10.1038/508290c

    Five genetically distinct lion populations roam in Africa and Asia — a finding that hints at greater diversity in these animals than previously thought.A team led by Ross Barnett, now at the University of Copenhagen, analysed mitochondrial DNA (mtDNA) from the remains of 14

    Categories: Journal Articles
  • Conservation biology: Unique birds top conservation list
    [Apr 2014]

    Conservation biology: Unique birds top conservation list

    Nature 508, 7496 (2014). doi:10.1038/508290d

    An analysis of evolutionary relationships between all of the world's known birds prioritizes some of them for conservation on the basis of their genetic uniqueness.Walter Jetz of Yale University in New Haven, Connecticut, Arne Mooers of Simon Fraser University in Burnaby, Canada, and their

    Categories: Journal Articles
  • Civil engineering: Seismic 'shield' stops quake shake
    [Apr 2014]

    Civil engineering: Seismic 'shield' stops quake shake

    Nature 508, 7496 (2014). doi:10.1038/508291a

    An array of deep holes in the ground seems to lessen shaking in certain locations during a simulated earthquake.Stéphane Brûlé of soil-engineering company Ménard in Nozay, France, and his colleagues drilled a grid of boreholes 5 metres deep into the soil near Grenoble. A

    Categories: Journal Articles
  • Neurobiology: Surprising effects of prion drug
    [Apr 2014]

    Neurobiology: Surprising effects of prion drug

    Nature 508, 7496 (2014). doi:10.1038/508291b

    A chemical that combats pathogenic prion proteins in infected mouse cells worsens the problem in cells from other species. The finding could explain why the drug, quinacrine, has been ineffective in many clinical trials.Prion infections turn healthy proteins into abnormally folded forms, which cause

    Categories: Journal Articles
  • Materials: Printer squirts out nanotubes
    [Apr 2014]

    Materials: Printer squirts out nanotubes

    Nature 508, 7496 (2014). doi:10.1038/508291c

    Inkjet printers can produce thin films of carbon nanotubes for use as electrodes in stretchy electronic circuits.Yongtaek Hong and his colleagues at Seoul National University printed layers of single-walled carbon nanotubes onto a stretchable silicon-based material. The authors found that the electrical properties of

    Categories: Journal Articles
  • Neuroscience: Turn on the light to make myelin
    [Apr 2014]

    Neuroscience: Turn on the light to make myelin

    Nature 508, 7496 (2014). doi:10.1038/508291d

    Brain circuits change throughout life, and researchers in California have discovered a mechanism for one such change: the thickening of the myelin sheath that surrounds nerve fibres and helps neurons to fire.Michelle Monje and her co-workers at Stanford University School of Medicine studied mice

    Categories: Journal Articles
  • Biomechanics: Fast moves of fleeing fruit flies
    [Apr 2014]

    Biomechanics: Fast moves of fleeing fruit flies

    Nature 508, 7496 (2014). doi:10.1038/508291e

    To dodge predators, flies in flight execute banked turns in just a few wingbeats — much faster than the steering motions that have been previously observed in flies.Michael Dickinson and his colleagues at the University of Washington in Seattle used three high-speed cameras operating

    Categories: Journal Articles
  • Lionfish prove a main draw on Twitter
    [Apr 2014]

    Lionfish prove a main draw on Twitter

    Nature 508, 7496 (2014). doi:10.1038/508291f

    What types of research papers move a scientist to turn from test tube or data-crunch to spread the word on social media? Here are some papers that saw Twitter activity from researchers in early April.Lionfish took a bite of Twitter attention at the start

    Categories: Journal Articles
  • Seven days: 11–17 April 2014
    [Apr 2014]

    Seven days: 11–17 April 2014

    Nature 508, 7496 (2014). http://www.nature.com/doifinder/10.1038/508292a

    The week in science: Japan reapproves use of nuclear power, second sighting of an exotic tetraquark, and biotech stocks plunge.

    Categories: Journal Articles
  • Mini satellites prove their scientific power
    [Apr 2014]

    Mini satellites prove their scientific power

    Nature 508, 7496 (2014). http://www.nature.com/doifinder/10.1038/508300a

    Author: Nicola Jones

    Proliferation of ‘CubeSats’ offers fresh and fast way to gather space data.

    Categories: Journal Articles
  • Toxicology: The plastics puzzle
    [Apr 2014]

    Toxicology: The plastics puzzle

    Nature 508, 7496 (2014). http://www.nature.com/doifinder/10.1038/508306a

    Author: Josie Glausiusz

    When toxicologists warned that the plastics ingredient BPA might be harmful, consumers clamoured for something new. But problems persist.

    Categories: Journal Articles
  • Policy: Bring sustainable energy to the developing world
    [Apr 2014]

    Policy: Bring sustainable energy to the developing world

    Nature 508, 7496 (2014). doi:10.1038/508309a

    Authors: Reid Detchon & Richenda Van Leeuwen

    Investment and policies must support cheap, clean energy technologies to cut both poverty and climate change, say Reid Detchon and Richenda Van Leeuwen.

    Categories: Journal Articles