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<jats:title>Extending Quantum Memory</jats:title> <jats:p> Practical applications in quantum communication and quantum computation require the building blocks—quantum bits and quantum memory—to be sufficiently robust and long-lived to allow for manipulation and storage (see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6086" page="1239" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1223439">Boehme and McCarney</jats:related-article> </jats:bold> ). <jats:bold> Steger <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1280" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1217635">1280</jats:related-article> ) demonstrate that the nuclear spins of <jats:sup>31</jats:sup> P impurities in an almost isotopically pure sample of <jats:sup>28</jats:sup> Si can have a coherence time of as long as 192 seconds at a temperature of ∼1.7 K. In diamond at room temperature, <jats:bold> Maurer <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1283" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1220513">1283</jats:related-article> ) show that a spin-based qubit system comprised of an isotopic impurity ( <jats:sup>13</jats:sup> C) in the vicinity of a color defect (a nitrogen-vacancy center) could be manipulated to have a coherence time exceeding one second. Such lifetimes promise to make spin-based architectures feasible building blocks for quantum information science. </jats:p>

<jats:title>From Long to Short</jats:title> <jats:p> When you play a string instrument, you raise the frequency, or pitch, of the note by shortening the vibrating portion of the string: Drop the length in half, and you hear a harmonic at double the frequency. It is possible to do essentially the same thing with light waves by using selective excitation and relaxation processes of the electrons in crystals or high-pressure gases through which the beam of light is directed to produce light harmonics. Over the past decade, researchers have been optimizing the conversion of red light to the far edge of the ultraviolet, which corresponds to tens of harmonics. <jats:bold> Popmintchev <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1287" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218497">1287</jats:related-article> ) now show that mid-infrared light can undergo a process in high-pressure gas to generate ultrahigh harmonics up to orders greater than 5000 in the x-ray regime. </jats:p>

<jats:title>No Shock Ahead of the Sun</jats:title> <jats:p> The boundary of the heliosphere is the region where the solar wind interacts with interstellar space, and it marks the edge of our solar system. Based on observations from NASA's Interstellar Boundary Explorer, <jats:bold> McComas <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1291" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1221054">1291</jats:related-article> , published online 10 May; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6086" page="1243" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1223677">Redfield</jats:related-article> </jats:bold> ) determined values for local interstellar parameters—such as speed, direction, and temperature—and show that these and other recent constraints are not consistent with a bow shock ahead of the heliosphere, as previously believed. </jats:p>

<jats:title>To the Next Level</jats:title> <jats:p> Block copolymers will spontaneously separate into a range of microstructures that depend on the polymer block lengths and chemical compositions, and have been used as a templating material because one can selectively etch or functionalize one of the blocks. However, creating a template that is more than one layer thick is challenging. <jats:bold> Tavakkoli K. G. <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1294" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218437">1294</jats:related-article> ) used an array of posts to provide independent and simultaneous control of the morphology and orientation of two layers of block copolymers and were able to create local variations in the curvature and spacing of the domains. </jats:p>

<jats:title>Pluses and Minuses</jats:title> <jats:p> Because of their high surface area and tunable electronic structure, nanoparticles are of interest for next-generation photocatalysis and light-harvesting applications. Many of these applications involve electron transfer events at the particle surface after light absorption. <jats:bold> Schrauben <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1298" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1220234">1298</jats:related-article> ) now show, through a series of radical trap kinetic studies, that proton transfer can concurrently accompany electron transfer at the solvent interfaces of two common nanoparticle formulations (oxides of titanium and of zinc). The results may help in the optimization of particle structure and energetics. </jats:p>

<jats:title>The Rains of Change</jats:title> <jats:p> Approximately 500 to 400 thousand years ago, a fundamental change in the nature of glacial cycles occurred, including a shift to larger amplitude variations in atmospheric carbon dioxide concentrations and global temperatures. <jats:bold> Meckler <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1301" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218340">1301</jats:related-article> , published online 3 May; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6086" page="1242" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1223527">Kurita</jats:related-article> </jats:bold> ) present a stalagmite record from Borneo which provides a record of precipitation from 550,000 to 200,000 years ago. The amount of regional precipitation was similar during all four of the interglacials during that interval, and drying events during glacial terminations corresponded with cooling events in high northern latitudes. </jats:p>

<jats:title>Honey Bees Beware of the Mite</jats:title> <jats:p> The emergence of a virulent form of a viral disease that has long been associated with the world-wide death of honey bees has occurred in the Hawaiian archipelago. <jats:bold> Martin <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1304" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1220941">1304</jats:related-article> ) exploited this unique situation to study the mechanisms behind the emergence. Honey bee populations have long been established on the isolated Hawaiian Islands but only recently have some islands become infested with the <jats:italic>Varroa</jats:italic> mite. This mite has selected for a single viral pathogen-deformed wing virus among the honey bee population, with the appearance of a single dominant virus strain, which has now spread worldwide. Thus, a normally benign viral pathogen has become one of the most widely distributed and contagious insect viruses on the planet. </jats:p>

<jats:title>Keeping Mitochondria in the Pink</jats:title> <jats:p> Pink1 is a mitochondrial kinase, and loss of Pink1 function in flies and mice results in the accumulation of inefficient mitochondria. In a screen for modifiers of the Parkinson-associated gene, <jats:italic>pink1</jats:italic> , <jats:bold> Vos <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1306" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1218632">1306</jats:related-article> , published online 10 May; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6086" page="1241" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1223812">Bhalerao and Clandinin</jats:related-article> </jats:bold> ) identified the fruit fly homolog of UBIAD1, “Heix.” UBIAD1 was localized in mitochondria and was able to convert vitamin K <jats:sub>1</jats:sub> into vitamin K <jats:sub>2</jats:sub> /menaquinone (MK- <jats:italic>n, n</jats:italic> the number of prenylgroups). In bacteria, vitamin K <jats:sub>2</jats:sub> /MK- <jats:italic>n</jats:italic> acts as an electron carrier in the membrane and, similarly, in <jats:italic>Drosophila</jats:italic> , mitochondrial vitamin K <jats:sub>2</jats:sub> appeared to act as an electron carrier to facilitate adenosine triphosphate production. Fruit flies that lack <jats:italic>heix</jats:italic> showed severe mitochondrial defects that could be rescued by administering vitamin K <jats:sub>2</jats:sub> . </jats:p>

<jats:title>Actin Up</jats:title> <jats:p> Actomyosin interactions lie at the heart of fundamental cellular processes—including morphogenesis, establishment of polarity, and overall motility—but the general principles driving the spatiotempotal orchestration of these interactions have remained elusive. Working in vitro, using micropatterned substrates, <jats:bold> Reymann <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1310" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1221708">1310</jats:related-article> ) demonstrate that myosins can use a “selection orientation” mechanism to pull selectively on actin filaments, contract the actin network and disassemble it, or walk on the filaments, align them, allow their growth, and control filament orientation. </jats:p>

<jats:title>The Mycobiome</jats:title> <jats:p> In the past few years, much attention has been given to the trillions of bacterial inhabitants in our guts and the myriad of ways in which they influence our overall health. But what about fungi? <jats:bold> Iliev <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1314" related-article-type="in-this-issue" vol="336" xlink:href="10.1126/science.1221789">1314</jats:related-article> ) now report that mice and humans, along with several other mammals, contain a resident intestinal population of fungi. Deletion of Dectin-1, which acts as a major innate immune sensor for fungi, led to enhanced susceptibility and worse pathology in a chemically induced model of colitis in mice. A polymorphism in the gene that encodes Dectin-1 has been observed in patients with ulcerative colitis, which hints that, besides the traditional bacterial microbiome, alterations in the “mycobiome” may also play a role in health and disease. </jats:p>