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<jats:p> A monthly roundup of recent news and projects of <jats:italic>Science</jats:italic> 's publisher, the American Association for the Advancement of Science. </jats:p>

<jats:p>Observations of a distant star reveal a magnetic activity cycle similar to that of the Sun.</jats:p>

<jats:title>Improving Earth Models</jats:title> <jats:p> The geophysical processes responsible for shaping the planet's surface and interior need largescale simulations, but to achieve high resolution at these scales is costly and tends to focus on gradual processes such as plate tectonics. By using large parallel supercomputers, <jats:bold> Stadler <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="1033" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1191223">1033</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5995" page="1020" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1194858">Becker</jats:related-article> </jats:bold> ; see the cover) have improved on a commonly used method—adaptive mesh refinement—to increase the resolution of global geodynamic models to the scale of a single kilometer and been able to reveal unexpected insights into localized processes, such as subduction zone mechanics, thermal anomalies in the lower mantle, and the speed of movement of oceanic plates. </jats:p>

<jats:title>Human Adenovirus Structures</jats:title> <jats:p> Human adenoviruses may be a common cause of acute infections in humans, but they can also be used as vectors for vaccine and therapeutic gene transfer. Rational engineering of safe adenovirus vectors has been hampered by a lack of high-resolution structural information. Two papers now describe the structure of human adenovirus using complementary techniques. <jats:bold> Reddy <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="1071" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1187292">1071</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5995" page="1026" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1194922">Harrison</jats:related-article> </jats:bold> ) have determined the crystal structure at 3.5 angstrom resolution, while <jats:bold> Liu <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="1038" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1187433">1038</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5995" page="1026" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1194922">Harrison</jats:related-article> </jats:bold> ) solved the structure to 3.6 angstrom resolution by electron microscopy. Together the structures provide insights into viral assembly, stabilization, and cell entry mechanisms. </jats:p>

<jats:title>Black Holes as Tools</jats:title> <jats:p> When confronted with a difficult problem, physicists often resort to mapping it to a more tractable one. A good example of this strategy is provided by new developments linking string theory and condensed-matter physics to make theoretical connections between gravity and complex systems of interacting electrons. This theoretical convergence provides a description of Fermi liquids, which can be thought of as interacting systems of electrons whose excitations can be expressed in terms of non-interacting quasiparticles. Several interesting systems elude quasiparticle description, but <jats:bold> Faulkner <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="1043" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1189134">1043</jats:related-article> , published online 5 August) have now developed a mathematical framework that describes the non-Fermi liquid represented by the strange metal phase of cuprate high-temperature superconductors. They calculate the electronic response and, for a particular value of a tunable parameter, recover the linear resistivity. Further development of this framework may allow elucidation of other exotic properties of the cuprates and similar complex systems. </jats:p>

<jats:title>Cracking Up</jats:title> <jats:p> Transform faults perpendicular to mid-ocean ridges are some of the most prominently visual features on the sea floor. Because they form slowly over thousands of years, the lack of observational data means their mechanism of formation has remained controversial. Taking a numerical modeling approach, <jats:bold>Gerya</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1047" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1191349">1047</jats:related-article> ) suggests that due to asymmetric growth of the plate boundary, sections of the mid-ocean ridge become unstable and eventually rotate 90°. As the ridge continues to grow, the transform faults continue to develop long after their initiation. This mechanism also explains how offsets of these transform faults occur discontinuously as a result of new fractures at the ridge. </jats:p>

<jats:title>Over the Moon</jats:title> <jats:p> Based on recent analyses of lunar rocks, it has been argued that the lunar interior contained much more water than previously thought. <jats:bold> Sharp <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="1050" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1192606">1050</jats:related-article> , published online 5 August) measured the chlorine isotope content of lunar samples returned by the Apollo missions and found that the spread in their chlorine isotope composition is 25-fold greater than for rocks and minerals that have been measured from Earth and meteorites. This result implies that the hydrogen content of the Moon (and therefore its water content) is much lower than suggested by recent studies. </jats:p>

<jats:title>Swelling Pores</jats:title> <jats:p> Porosity is a key parameter when selecting materials for catalysts, chemical separations, gas storage, host-guest interactions, and related chemical processes. In most cases the porosity of a material is fixed. <jats:bold> Rabone <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="1053" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1190672">1053</jats:related-article> ; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5995" page="1025" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1195176">Wright</jats:related-article> </jats:bold> ) have described a molecular material in which the size of the pores changed during the sorption process. The porosity increased because a dipeptide linker between metal centers reoriented during uptake of some gases, thus improving the capacity of the material to adsorb. </jats:p>

<jats:title>Forced Open</jats:title> <jats:p> Traditionally, the study of reaction chemistry has relied on random encounters between molecules to initiate the proceedings. Heating and stirring increase the power and frequency of such encounters but provide little finer control. Very recently, chemists have learned how to initiate reactions more directly by embedding precursors in the backbone of a polymer large enough to manipulate with shear forces. <jats:bold> Lenhardt <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="1057" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1193412">1057</jats:related-article> ) applied this technique to a cyclopropyl ring-opening reaction. When the strained triangular carbon rings were embedded within a polymer, shear force applied by sonication ruptured their bonds as the polymer backbone stretched. The taut polymer then redirected the ring-opened intermediates toward a product differently arranged from that generated by simple heating. </jats:p>

<jats:title>Toward a General Flu Vaccination</jats:title> <jats:p> Current seasonal influenza virus vaccines are targeted against specific viral strains and do not provide broad, durable protection. Seasonal influenza vaccines induce protective antibody responses against regions of viral hemagglutinin (HA) that rapidly mutate so that very soon, the virus becomes resistant to vaccination. Conserved regions of HA also exist, and a major goal of influenza vaccine development is to design a vaccine that elicits antibodies against the conserved regions so that protection against a wide range of viral strains is achieved. <jats:bold> Wei <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="1060" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1192517">1060</jats:related-article> , published online 15 July; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="5995" page="1021" related-article-type="in-this-issue" vol="329" xlink:href="10.1126/science.1195116">Doms</jats:related-article> </jats:bold> ) show that a combined HA DNA prime, followed by boosting with a seasonal vaccine, elicits broadly cross-reactive neutralizing antibody responses in mice, ferrets, and nonhuman primates, which were protective in mice and ferrets against heterologous influenza challenge. The neutralizing antibodies were directed against the conserved HA stem region, which indicates the possibility that a more broadly protective vaccine against influenza could be developed. </jats:p>