Catálogo de publicaciones - revistas

<jats:title>I'll see your program and raise you mine</jats:title> <jats:p> One of the fundamental differences between playing chess and two-handed poker is that the chessboard and the pieces on it are visible throughout the entire game, but an opponent's cards in poker are private. This informational deficit increases the complexity and the uncertainty in calculating the best course of action—to raise, to fold, or to call. Bowling <jats:italic>et al.</jats:italic> now report that they have developed a computer program that can do just that for the heads-up variant of poker known as Limit Texas Hold 'em (see the Perspective by Sandholm). </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="6218" page="145" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1259433">145</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6218" page="122" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa4614">122</jats:related-article> </jats:p>

<jats:title>Watching the silver lining inside</jats:title> <jats:p> Some types of batteries contain both a transition metal reducible metal, such as the cathode material Ag <jats:sub>2</jats:sub> VP <jats:sub>2</jats:sub> O <jats:sub>8</jats:sub> . During operation, both Ag and V ions are reduced, and the Ag atoms can form wires to enhance the internal conductivity. Kirshenbaum <jats:italic>et al.</jats:italic> probe the discharge of a battery at different rates and track the formation of Ag atoms using in situ energy-dispersive x-ray diffraction (see the Perspective by Dudney and Li). They show how the discharge rate affects whether the Ag or V is preferentially reduced and also the distribution of the Ag atoms, and then correlate this to the loss of battery capacity at higher discharge rates. </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="6218" page="149" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1257289">149</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6218" page="131" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa2870">131</jats:related-article> </jats:p>

<jats:title>Popping materials and devices from 2D into 3D</jats:title> <jats:p> Curved, thin, flexible complex three-dimensional (3D) structures can be very hard to manufacture at small length scales. Xu <jats:italic>et al.</jats:italic> develop an ingenious design strategy for the microfabrication of complex geometric 3D mesostructures that derive from the out-of-plane buckling of an originally planar structural layout (see the Perspective by Ye and Tsukruk). Finite element analysis of the mechanics makes it possible to design the two 2D patterns, which is then attached to a previously strained substrate at a number of points. Relaxing of the substrate causes the patterned material to bend and buckle, leading to its 3D shape. </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="6218" page="154" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1260960">154</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6218" page="130" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa2643">130</jats:related-article> </jats:p>

<jats:title>Mechanically soft neural implants</jats:title> <jats:p> When implanting a material into the body, not only does it need the right functional properties, but it also needs to have mechanical properties that match the native tissue or organ. If the material is too soft, it will be mechanically degraded, and if it is too hard it may get covered with scar tissue or it may damage the surrounding tissues. Starting with a transparent silicone substrate, Minev <jats:italic>et al.</jats:italic> patterned microfluidic channels to allow for drug delivery, and soft platinum/silicone electrodes and stretchable gold interconnects for transmitting electrical excitations and transferring electrophysiological signals. In tests of spinal cord implants, the soft neural implants showed biointegration and functionality within the central nervous system. </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="6218" page="159" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1260318">159</jats:related-article> </jats:p>

<jats:title>Traveling a long way past the junction</jats:title> <jats:p> Diodes are central components of modern electronic circuits. They essentially consist of two semiconductors sandwiched together, with one deficient in electrons (p), the other enriched (n). Najafi <jats:italic>et al.</jats:italic> used ultrafast electron microscopy to study the dynamics in a silicon diode on a time scale of trillionths of a second. They discovered that when light excites the diode's charge carriers, those carriers migrate much farther past the p-n junction than standard models would imply. The authors explain the results using a ballistic transport model. </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="6218" page="164" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa0217">164</jats:related-article> </jats:p>