Editors' Choice

Science  01 Aug 2014:
Vol. 345, Issue 6196, pp. 527
  1. Abiotic Stress

    How plants survive (salt) stress

    1. Pamela J. Hines

    Foxtail millet survives in high salt conditions


    Foxtail millet, a grain crop cultivated in China since the sixth century BC, tolerates high salt concentrations well. All land plants produce proteins called remorins, several of which help plants respond to abiotic (environmental) stress. To determine whether foxtail millet uses remorins to help protect it from excess salt, Yue et al. first identified 11 remorin genes in this plant. When the plants grew in salty soil, they produced a remorin called SiREM6. Engineering Arabidopsis plants to express SiREM6 allowed the plants to survive better in salty conditions. Their advantage increased with the salinity: While brackish water killed normal Arabidopsis plants, SiREM6-expressing plants survived.

    PLOS ONE 9, e100772 (2014).

  2. Cognitive Psychology

    Developing a judgment of confidence

    1. Gilbert Chin

    When you place a bet, you need to estimate your chance of winning, and you also need to know the accuracy of your estimate. That is, when the odds appear to be in your favor, but you're not entirely sure, you'll make a smaller wager than when you're rock-solid certain. Adults who are good judges of their own accuracy tend to be better at problem-solving, regulating their emotions, and thinking critically, among other skills. Vo et al. wondered whether this also holds true for children. The authors found that 5- to 8-year-old children are pretty good at making judgments about their accuracy when it comes to estimating quantities, but they don't evaluate themselves as well when comparing facial emotions.

    Psychol. Sci. 25, 10.1177/0956797614538458 (2014).

  3. Development

    The long and short of hair growth

    1. Lisa D. Chong

    FGF5 controls eyelash length


    The length of your eyelashes probably differs from the length of the hair on your head—and unlike your hair, your eyelashes can never reach your shoulders. What controls how long hair can get? To find out, Higgins et al. studied people with a rare disorder called familial trichomegaly, who have very long eyelashes and longer hair on the arms. They found that these people had a mutation in the gene that encodes fibroblast growth factor 5 (FGF5). When human hair follicles produce FGF5, they stop growing hair. Targeting FGF5 could potentially control the growth and rest phases of hair follicles, preventing unwanted hair from sprouting or growing longer lashes and locks.

    Proc. Natl. Acad. Sci. U.S.A. 10.1073/pnas.1402862111 (2014).

  4. Education

    Promoting evidence-based teaching

    1. Melissa McCartney

    Empirical studies of science educational methods illuminate the best practices for getting students to learn. But why don't more science educators use such evidence-based teaching methods in their classrooms? They might not have access to the studies, DeChenne et al. report. The authors examined the role of practitioner-focused, discipline-based education research (DBER) journals in promoting and encouraging postsecondary teachers to adopt laboratory exercises supported by education research. Results showed a missed opportunity: DBER journals publish only a limited number of evidence-based instructional practices.

    J. Coll. Sci. Teach. 43, 89 (2014).

  5. Electron Transfer

    Electron tunneling or flickering resonance?

    1. Phil Szuromi

    When electrons move from one site to another in biological molecules and the transfer drops off exponentially with distance, physicists usually assume they're seeing the electrons quantum-tunneling through energy barriers. A theoretical study by Zhang et al. provides a different interpretation. Molecules with the right combination of sites, with energy levels that align fleetingly during structural fluctuations, can produce the same decay signature. These “flickering resonances” temporarily create a band-like state for the electron, and as more sites are involved (corresponding to longer distances), the probability of creating the resonance drops exponentially. This mechanism operates over scale lengths of up to about 15 angstroms and could explain the short-distance electron transfer between bases in DNA.

    Proc. Natl. Acad. Sci. U.S.A. 10.1073 pnas.1316519111 (2014).

  6. Marine Biology

    Ship strikes threaten blue whale numbers

    1. Virginia Morell

    Whale-ship collisions may be behind low blue whale population counts despite international protections. Irvine et al. used satellites to track 171 blue whales off California over 15 years. The whales, part of the eastern North Pacific population, returned each summer to krill-rich upwelling zones off Santa Barbara and San Francisco—areas also crossed by major shipping lanes. At least three blue whales were killed by ship strike during 2 weeks in 2007. But a similar problem in Canada's Bay of Fundy offers hope: Eleven years ago, its maritime industry moved a shipping lane and reduced speed limits, reducing the likelihood of vessels striking right whales by 80%.

    A blue whale killed by a ship strike


    PLOS ONE 10.1371/journal.pone.0102959(2014).

  7. Microbial Pathogens

    How to make a not-so-painful ulcer

    1. Stella M. Hurtley

    Buruli ulcer disease causes extensive skin lesions and can be deadly, but the lesions themselves don't hurt, which can stop patients from seeking the appropriate care. The pathogen Mycobacterium ulcerans causes Buruli ulcers and also alleviates the pain. Although many scientists studying this disease thought the pathogen caused nerve damage that blocked the pain, Marion et al. now show that the mycobacteria produce the mycolactone toxin, which causes analgesia by blocking the function of pain-responsive nerves. The findings could potentially help researchers develop a whole new class of painkillers.

    Cell 157, 1565 (2014).

  8. Geophysics

    Ample explanation for seismic variation

    1. Brent Grocholski

    Geophysicists use seismic waves to make images of Earth's interior, but how they interpret those pictures depends on the properties of the minerals that make up the mantle. Wu and Wentzcovitch show that when the electron configuration of the iron in one of the most abundant minerals in the mantle, ferropericlase, changes at depths of 1000 km and greater, so does the way seismic waves propagate. The authors discuss several seismic features of the mantle previously thought to reflect different arrangements of minerals, such as compressional wave speed variations at depths of around 1750 km. Such features could be due not to mineralogy but to this electronic spin effect.

    Proc. Nat. Acad. Sci. U.S.A. 10.1073 pnas.1322427111 (2014).

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