Editors' Choice

Science  31 Jul 2015:
Vol. 349, Issue 6247, pp. 491
  1. Infectious Disease

    Innate lymphoid cells to the rescue

    1. Kristen L. Mueller

    Innate lymphoid cells help control damaging Clostridium difficile infection

    PHOTO: DR. KARI LOUNATMAA/SCIENCE SOURCE

    Most people enter the hospital with the hope of getting better, but recent increases in hospital-acquired infections have made hospitals deadly in their own right. For instance, deaths caused by the enteric bacterium Clostridium difficile increased by 400% in the last decade. C. difficile is an opportunistic pathogen that takes advantage of disruptions in the microbiota caused by antibiotic treatment. Abt et al. provide new insight into how the host defends itself against this unwelcome intruder. Studying C. difficile–infected mice, the authors found that the mice required innate lymphoid cells (ILCs) to survive the infection. ILCs did not substantially contribute to reducing pathogen burden but instead appeared to limit pathology and systemic dissemination.

    Cell Host Microbe 18, 27 (2015).

  2. Signal Transduction

    Signaling probed by single-molecule tracking

    1. L. Bryan Ray

    Developmental signaling through the so-called Hedgehog pathway is transduced through the receptor-like protein Smoothened. Hedgehog signaling requires highly specific localization of Smoothened in target cells at the primary cilium, a structure that functions somewhat like an antenna to receive and transmit signals. Milenkovic et al. tracked movement of single molecules of Smoothened in the cilia of cultured mouse embryo fibroblasts. Movement of Smoothened was restricted by binding events at the base of the cilium. Activation of Hedgehog signaling decreased the affinity of such binding. Such regulated binding of Smoothened to its yet-to-be-defined partner(s) within the cilium is likely an important step in the Hedgehog signaling mechanism.

    Proc. Natl. Acad. Sci. U.S.A. 10.1073/pnas.1510094112 (2015).

  3. Neuroscience

    At the center of our own spatial social network

    1. Laura Schuhmacher

    Neurons in the hippocampus create a maplike representation of the environment, forming what is called spatial memory. Tavares et al. suggest that humans also create a 3D map of social space with themselves at the center. They measured the representation of a map of social interactions based on a role-playing game where participants could interact with fictional characters along power (dominance, hierarchy, etc.) and affiliation (intimacy, trustworthiness, etc.) gradients, while placed in an fMRI scanner. Left hippocampal activity correlated with the angle of a vector created by these two measures, but not by either of them alone, while the strength of correlation also depended on the social skills and personality traits like neuroticism and conscientiousness of the individual.

    Neuron 87, 23110.1016/j.neuron.2015.06.011 (2015).

  4. Geophysics

    Allowing faults out of lock-up

    1. Brent Grocholski

    Relict microatoll on southeastern island of Simeulue, Sumatra

    PHOTO: ARON J. MELTZNER/EARTH OBSERVATORY OF SINGAPORE

    The crust around a locked, earthquake-prone fault responds to the two sides pulling in opposite directions by bowing and bulging over time. Meltzner et al. and Wesson et al. challenge a common assumption that this deformation progresses mostly in a uniform, linear way. Deformation shows up in seafloor bathymetry, which changes abruptly for both Sumatra and Isla Santa Maria, Chile, over a seismic cycle. Periods during which the fault is weakly locked explains the non-uniform behavior. Quantifying the effect clarifies subduction zone mechanics, which may require updating estimates of earthquake hazard.

    Quat. Sci. Rev. 10.1016/j.quascirev.2015.06.003 (2015); Nat. Geosci. 10.1038/ngeo2468 (2015).

  5. Obesity Management

    New drug—and new hope—for a losing game

    1. Paula A. Kiberstis

    Injectable weight loss: In the long run, is it too good to be true?

    PHOTO: DR. P. MARAZZI/SCIENCE SOURCE

    Many people would gladly trade a dip in the fountain of youth for a safe drug that makes them thinner. Despite years of effort, the pharmaceutical industry has yet to deliver such a drug. New hope is offered by Pi-Sunyer et al., who report the results of a 56-week, double-blind clinical trial examining the metabolic effects of a drug called liraglutide, which mimics a hormone produced in the gastrointestinal tract (glucacon-like peptide 1) that increases satiety. People taking liraglutide, in conjunction with dieting and exercise, lost a mean of 8.4 kilograms as compared with 2.8 kilograms in those taking a placebo. Drawbacks include the delivery method (injection) and hints that cessation of the drug results in regain of weight.

    New Engl. J. Med. 373, 11 (2015).

  6. Nuclear Chemistry

    Subsurface corrosion of uranium

    1. Nicholas S. Wigginton

    Uranium dioxide, the most common form of nuclear fuel, becomes mobile as it oxidizes. Although oxidative corrosion is inherently a surface-mediated process, interstitial oxygen atoms can induce oxidation many atomic layers deeper. By detailing the surface structure and composition of UO2 after exposure to oxygen in air and water, Stubbs et al. show that oxidation does not follow a classical diffusion pattern. Instead, interstitial oxygens preferentially occupy every third atomic layer below the terminal (111) surface. This pattern is a product of the delocalized electronic structure of nonsurface U atoms, which also allows for the coexistence of three U oxidation states.

    Phys. Rev. Lett. 114, 246103 (2015).

  7. Applied Optics

    Dealing with big data

    1. Ian S. Osborne

    Data generation often occurs at such a high rate that it cannot be analyzed on the fly but must be stored and archived for access later on. While banks of magnetic hard drives are the storage medium of choice at present, the total capacity, recording times, and required energy burden are not expected to keep pace with the data generation rate. Li et al. look to optical recording as a possible solution. Combining superresolution nanoscopy to record tiny binary bits in a photosensitive medium with multifocusing array techniques to access multiple layers within the medium, it should be possible to achieve storage capacities of about 30 terabits per disk and data recording rates exceeding gigabits per second.

    Optica 2, 567 (2015).