Catálogo de publicaciones - revistas

<jats:title>The when of Mediterranean water outflow</jats:title> <jats:p> The trickle of water that began to flow from the Mediterranean Sea into the Atlantic Ocean after the opening of the Strait of Gibraltar turned into a veritable flood by the end of the Pliocene 2 to 3 million years ago. It then began to influence large-scale ocean circulation in earnest. Hernández-Molina <jats:italic>et al.</jats:italic> describe marine sediment cores collected by an ocean drilling expedition (see the Perspective by Filippelli). The results reveal a detailed history of the timing of Mediterranean outflow water activity and show how the addition of that warm saline water to the cooler less-salty waters of the Atlantic was related to climate changes, deep ocean circulation, and plate tectonics. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1244" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1251306">1244</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1228" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1255553">1228</jats:related-article> </jats:p>

<jats:title>Improving stroke recovery by timing treatment</jats:title> <jats:p> Patients recovering from strokes often fight a long uphill battle, with mixed results. Studying the effect of physical training on regeneration from damaged nerves in a model of stroke in rats, Wahl <jats:italic>et al.</jats:italic> show that timing matters. First, the researchers gave the rats a stroke, which damaged their ability to reach for food pellets with their forelimbs. The researchers then gave them physical training and treated them with an antibody to encourage neural regeneration. The rats improved more when the researchers waited until after the antibody treatment to start the training. Damaged circuits, it seems, need a little time to regrow before being called into action. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1250" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1253050">1250</jats:related-article> </jats:p>

<jats:title>Testing nonlocality for many particles</jats:title> <jats:p> Distant parts of a quantum-mechanical system can be correlated in ways that cannot be described classically—a concept known as nonlocality. Tura <jats:italic>et al.</jats:italic> propose a simple test for nonlocality in systems with multiple particles. The test involves quantities that should readily be measurable in, for example, cold atom experiments. This is an improvement over currently available tests, which are difficult to implement experimentally. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1256" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1247715">1256</jats:related-article> </jats:p>

<jats:title>Tilting just right makes atoms tunnel</jats:title> <jats:p> One of the most fascinating phenomena in the quantum world is the ability of particles to go through an energy barrier — a process called quantum tunneling. Meinert <jats:italic>et al.</jats:italic> studied the dynamics of quantum tunneling in an optical lattice of strongly interacting atoms. When the lattice was suddenly tilted, the atoms, originally each in their own lattice site, tunneled to non-neighboring sites. </jats:p> <jats:p> Science, this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1259" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1248402">1259</jats:related-article> </jats:p>

<jats:title>Avoiding back-action in quantum measurements</jats:title> <jats:p> The very process of measuring a quantum system has an influence on the system through the process of back-action. Suh <jats:italic>et al.</jats:italic> used a back-action evasion scheme to monitor the motion of a miniature oscillator without influencing its motion (see the Perspective by Bouwmeester). The scheme should help in the understanding of the fundamental limits associated with measurement and will have practical implications in providing a low-temperature thermometer and a probe of extremely weak forces. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1262" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1253258">1262</jats:related-article> </jats:p>

<jats:title>Cycling water through the transition zone</jats:title> <jats:p> The water cycle involves more than just the water that circulates between the atmosphere, oceans, and surface waters. It extends deep into Earth's interior as the oceanic crust subducts, or slides, under adjoining plates of crust and sinks into the mantle, carrying water with it. Schmandt <jats:italic>et al.</jats:italic> combined seismological observations beneath North America with geodynamical modeling and high-pressure and -temperature melting experiments. They conclude that the mantle transition zone—410 to 660 km below Earth's surface—acts as a large reservoir of water. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1265" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1253358">1265</jats:related-article> </jats:p>

<jats:title>Not too fast, not too slow, somewhere in between</jats:title> <jats:p> In early depictions, dinosaurs lumbered slowly, dragging their tails. More recently, we have imagined them lifting their tails and running. The question boils down to whether dinosaurs had energetic systems closer to those of rapidly metabolizing mammals and birds, or to those of slower reptiles that do not internally regulate their body temperature. However, determining the metabolic rate of extinct organisms is no easy task. Grady <jats:italic>et al.</jats:italic> analyzed a huge data set on growth rate in both extinct and living species, using a method that considers body temperature and body size. Dinosaur metabolism seems to have been neither fast nor slow, but somewhere in the middle—so, dinosaurs did not fully regulate their internal temperature but they were also not entirely at the whim of the environment; neither slow goliaths nor supercharged reptiles. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6189" page="1268" related-article-type="in-this-issue" vol="344" xlink:href="10.1126/science.1253143">1268</jats:related-article> </jats:p>