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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:title>Connections by Degree</jats:title> <jats:p> A recent explosion of data and of large projects dealing with the problem of connectivity in the human brain has not yet led to clear strategies to study connectomes. <jats:bold>DeFelipe</jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" page="1198" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1193378">1198</jats:related-article> ) reviews the intellectual history of the field, from the 19th-century studies of the seminal anatomist Ramon y Cajal to the very recent approaches and myriad new technologies applied by many laboratories trying to understand the organization of the human cerebral cortex. </jats:p>

<jats:title>Macromolecular Message Translation</jats:title> <jats:p> The ribosome is a macromolecular machine that translates the sequence of messenger RNA into proteins in all living cells. Structures of prokaryotic ribosomes have supplied insight into the conserved features of such protein synthesis; however, eukaryotic translation has additional levels of complexity. <jats:bold> Ben-Shem <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="1203" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1194294">1203</jats:related-article> ) have determined the crystal structure of the yeast 80S ribosome at 4.15 angstrom resolution. The ribosome is in a ratcheted conformation, which is a state that is an intermediate in the translocation of messenger RNA and transfer RNA. The crystal structure provides the molecular underpinning for existing biochemical and genetic data and will inform the design of functional experiments. </jats:p>

<jats:title>Stellar Jets</jats:title> <jats:p> Supersonic jets of energized charged particles are a common phenomenon in astrophysics, emanating from sources that range widely in mass: from brown dwarfs to super massive black holes in the centers of galaxies. <jats:bold> Carrasco-González <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="1209" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1195589">1209</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="6008" page="1184" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1199141">Ray</jats:related-article> </jats:bold> ) present observations, of a jet emanating from a young stellar object, which show that the jet is magnetized and has characteristics that are similar to those of jets found in much larger and more massive systems. The results support the idea that all astrophysical jets are launched and collimated through the same basic mechanism, involving launching of material along magnetic field lines. </jats:p>

<jats:title>Dressing-Up Diamond Defects</jats:title> <jats:p> The spin states of nitrogen vacancy defects in diamond are being explored as information carriers and memories in quantum information systems. Their long lifetimes, fast manipulation rates, and the ability to couple them to adjacent electronic and nuclear spins provide the necessary properties for implementation in solid-state quantum networks. To date, however, the readout of the spin state via photoluminescence, either directly or indirectly, results in the destruction of the spin state. <jats:bold> Buckley <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="1212" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1196436">1212</jats:related-article> , published online 14 October; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6008" page="1188" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1198299">Milburn</jats:related-article> </jats:bold> ) have formed a light-matter hybrid state in which the spin interacts with laser light to form a polariton state. This hybrid state can be optically probed to produce a nondestructive measurement and manipulation technique for the spin state of the nitrogen-vacancy center. </jats:p>

<jats:p>The extinction of dinosaurs at the Cretaceous/Paleogene (K/Pg) boundary was the seminal event that opened the door for the subsequent diversification of terrestrial mammals. Our compilation of maximum body size at the ordinal level by sub-epoch shows a near-exponential increase after the K/Pg. On each continent, the maximum size of mammals leveled off after 40 million years ago and thereafter remained approximately constant. There was remarkable congruence in the rate, trajectory, and upper limit across continents, orders, and trophic guilds, despite differences in geological and climatic history, turnover of lineages, and ecological variation. Our analysis suggests that although the primary driver for the evolution of giant mammals was diversification to fill ecological niches, environmental temperature and land area may have ultimately constrained the maximum size achieved.</jats:p>

<jats:title>Routes to Rare Zeolites</jats:title> <jats:p> Zeolites are microporous crystalline solids with well-defined structures. Although many naturally occurring ones have been obtained in laboratory synthesis, some have remained elusive. One of these, boggsite, is of interest for catalytic reactions because it has large channels defined by rings of 10 or 12 atoms that intersect within its crystalline lattice. <jats:bold> Simancas <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="1219" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1196240">1219</jats:related-article> ) report the synthesis of boggsite by using phosphazenes as the organic groups that directed the formation of rings during synthesis. These reagents can be readily modified—a feature that should allow greater flexibility in synthesis routes. </jats:p>

<jats:title>A Little Help from Hydrogen</jats:title> <jats:p> Biomass may one day displace petroleum as the chemical industry's primary feedstock. Currently, though, the primary hurdle for incorporating plant-derived material into existing process feeds is the high proportion of oxygen in its molecular frameworks. Rapid heating of the biomass followed by high-temperature treatment with zeolite catalysts can yield tractable quantities of useful commodity compounds such as ethylene and benzene, but much of the carbon is wasted in the process—diverted either toward gaseous CO and CO <jats:sub>2</jats:sub> , or solid coke. <jats:bold> Vispute <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="1222" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1194218">1222</jats:related-article> ) show that an intermediate step, in which hydrogen is catalytically incorporated into the heated material prior to zeolite treatment, can substantially raise the yield of useful products by reducing susceptibility to coking. </jats:p>

<jats:title>Deformed Sapphire</jats:title> <jats:p> The structure of sapphire consists of alternating sheets of oxygen ions and puckered aluminum ions. Although brittle at low temperature, the material can deform at high temperatures through structural dislocations. <jats:bold> Heuer <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="1227" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1192319">1227</jats:related-article> ) used a high-resolution transmission electron microscope and the negative spherical aberration imaging technique to distinguish between the columns of Al and O ions. Upon deformation, the Al ions moved into both tetrahedrally and octahedrally coordinated sites, and while the dislocation cores spread out, they remained uncharged and stoichiometric. The results may connect to the deformation behavior of other nonmetallic solids. </jats:p>

<jats:title>Lap Cats</jats:title> <jats:p> We all know that domestic cats lap milk, but perhaps fewer of us have thought about how they do this. <jats:bold> Reis <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="1231" related-article-type="in-this-issue" vol="330" xlink:href="10.1126/science.1195421">1231</jats:related-article> , published online 11 November; see the cover) have discovered that cats curl their tongues so that the top surface touches the water. Then, by lifting their tongues rapidly, a column of liquid grows by inertia until gravity induces its breakage and the cats close their jaws to capture the liquid. Lapping frequency is tuned to maximize the volume ingested, depending on the animal's mass; a relationship that holds as true for tabby cats as it does for lions. </jats:p>