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<jats:p>The removal of RNA inadvertently incorporated into our DNA is critical for maintaining genome integrity.</jats:p>

<jats:p>Twice awarded the Nobel Prize, a biochemist's work on protein and DNA structure opened the door to modern biomedical science.</jats:p>

<jats:title>Health Economy?</jats:title> <jats:p> The intensity of arguments over social science issues often seems inversely correlated with the quantity of experimental evidence. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="263" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246183"> <jats:bold> Taubman <jats:italic>et al.</jats:italic> </jats:bold> </jats:related-article> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="263" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246183">263</jats:related-article> , published online 2 January; see the Policy Forum by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="252" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1249341"> <jats:bold>Fisman</jats:bold> </jats:related-article> ) report on the latest analysis of an ongoing controlled experiment—the Oregon Health Insurance Experiment—that seeks to identify and quantify the effects of extending health insurance coverage to a low-income adult population. A substantial increase was observed in visits to the emergency departments of hospitals, corresponding to approximately 120 U.S. dollars per year more in hospital costs. </jats:p>

<jats:title>Stubbornly Spherical</jats:title> <jats:p> The shape of the electron's charge distribution reflects the degree to which switching the direction of time impacts the basic ingredients of the universe. The Standard Model (SM) of particle physics predicts a very slight asphericity of the charge distribution, whereas SM extensions such as supersymmetry posit bigger and potentially measurable, but still tiny, deviations from a perfect sphere. Polar molecules have been identified as ideal settings for measuring this asymmetry, which should be reflected in a finite electric dipole moment (EDM) because of the extremely large effective electric fields that act on an electron inside such molecules. Using electron spin precession in the molecule ThO, <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="269" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1248213"> <jats:bold> Baron <jats:italic>et al.</jats:italic> </jats:bold> </jats:related-article> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="269" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1248213">269</jats:related-article> , published online 19 December; see the cover; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="255" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246820">Brown</jats:related-article> </jats:bold> ) measured the EDM of the electron as consistent with zero. This excludes some of the extensions to the SM and sets a bound to the search for a nonzero EDM in other facilities, such as the Large Hadron Collider. </jats:p>

<jats:title>Topochemical Polymerization</jats:title> <jats:p> In a topochemical reaction, chemical changes start at active sites in the solid and then proceed autocatalytically to neighboring regions. If one starts with a monomer that can form ordered structures similar to the final polymer, it is possible to polymerize chains in a fully ordered state and thus make very long single chains. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="272" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1245875"> <jats:bold> Dou <jats:italic>et al.</jats:italic> </jats:bold> </jats:related-article> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="272" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1245875">272</jats:related-article> ; see the Perspective by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="258" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1249064"> <jats:bold>Goroff</jats:bold> </jats:related-article> ) describe an unexpected visible-light–induced polymerization of derivatives of a dye. Two of the derivatives underwent photoinduced single-crystal-to-single-crystal topochemical polymerization. </jats:p>

<jats:title>Renewable Breakdown Routine</jats:title> <jats:p> In order to transform cellulose-containing biomass into liquid fuels such as ethanol, it is first necessary to break down the cellulose into its constituent sugars. Efforts toward this end have focused on chemical protocols using concentrated acid or ionic liquid solvents, and on biochemical protocols using cellulase enzymes. <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="277" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246748"> Luterbacher <jats:italic>et al.</jats:italic> </jats:related-article> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="277" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246748">277</jats:related-article> ) now show that γ-valerolactone, a small molecule solvent that can itself be sourced renewably from biomass, promotes efficient and selective thermal breakdown of cellulose in the presence of dilute aqueous acid. </jats:p>

<jats:title>Regular Nanowires</jats:title> <jats:p> For a range of nanotechnology applications, semiconductor nanowires will need to be grown with high precision and control. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="281" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1244623"> <jats:bold> Chou <jats:italic>et al.</jats:italic> </jats:bold> </jats:related-article> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="281" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1244623">281</jats:related-article> ) studied the growth of gallium phosphide (GaP) nanowires using chemical vapor deposition within a transmission electron microscope and worked out conditions that could generate regular and predictable wire growth. </jats:p>

<jats:title>What Does It All Mean?</jats:title> <jats:p> Strong emissions of methane have recently been observed from shallow sediments in Arctic seas. <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="284" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246298"> Berndt <jats:italic>et al.</jats:italic> </jats:related-article> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="284" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246298">284</jats:related-article> , published online 2 January) present a record of methane seepage from marine sediments off the coast of Svalbard showing that such emissions have been present for at least 3000 years, the result of normal seasonal fluctuations of bottom waters. Thus, contemporary observations of strong methane venting do not necessarily mean that the clathrates that are the source of the methane are decomposing at a faster rate than in the past. </jats:p>

<jats:title>Long Live the Queen</jats:title> <jats:p> Eusociality is often considered to have arisen, at least in part, due to the inclusive fitness that workers gain through helping their queen sister to raise her offspring. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="287" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1244899"> <jats:bold> Van Oystaeyen <jats:italic>et al.</jats:italic> </jats:bold> </jats:related-article> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="287" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1244899">287</jats:related-article> ; see the Perspective by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="254" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1249285"> <jats:italic>Chapuisat</jats:italic> </jats:related-article> ) characterized the sterility-inducing queen pheromone across three distantly related eusocial hymenopterans (a wasp, a bumblebee, and a desert ant) and synthesized data across 69 other species. Queen pheromones appear to be remarkably conserved, which suggests that reproductive manipulation has ancient roots. </jats:p>

<jats:title> ATP Receptor in <jats:italic>Arabidopsis</jats:italic> </jats:title> <jats:p> As well as its role as an intracellular energy source, extracellular adenosine triphosphate (ATP) has diverse functions as a signaling molecule. ATP receptors have been identified in animal cells, but searches based on structural homology have not identified ATP receptors in plants. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="290" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.343.6168.290"> <jats:bold> Choi <jats:italic>et al.</jats:italic> </jats:bold> </jats:related-article> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6168" page="290" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.343.6168.290">290</jats:related-article> ) have now identified an ATP receptor in the model plant <jats:italic>Arabidopsis thaliana</jats:italic> by tracking down the cause of mutations that leave mutant plants unresponsive to ATP signals. The receptor identified carries an intracellular kinase domain and an extracellular lectin domain. </jats:p>