Catálogo de publicaciones - revistas

<jats:title>Learning when and what to learn</jats:title> <jats:p>Infants use “unexpectedness” as a cue for learning. Stahl and Feigenson studied how babies reacted when objects behaved in surprising ways (see the Perspective by Schulz). Babies who saw apparently solid and weighty objects moving through a wall or past the edge of a table without falling looked intently at them. When given the opportunity to explore these peculiar objects, they did so by banging them on the floor—as if to test their solidity—or dropping them—as if to test their weightiness.</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="6230" page="91" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa3799">91</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6230" page="42" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab0582">42</jats:related-article> </jats:p>

<jats:title>The whole mitoribosome at high resolution</jats:title> <jats:p> Mitochondria are thought to be the descendents of a prokaryotic cell that took up residence in a protoeukaryotic cell. Mitochondria retain a few genes involved in oxidative phosphorylation. To translate these genes, mitochondria contain highly divergent mitochondrial ribosomes, or mitoribosomes. Amunts <jats:italic>et al.</jats:italic> determined the high-resolution structures of complete mammalian mitoribosomes using cryoelectron microscopy. Mitoribosomes include an unusual mRNA binding channel. The findings elucidate how aminoglycoside antibiotics can inadvertently inhibit mitoribosomes and how mutations in mitoribosomes can lead to disease. </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="6230" page="95" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa1193">95</jats:related-article> </jats:p>

<jats:title>Making a molecular fossil lookalike</jats:title> <jats:p> Atoms are generally compact objects. However, if one of the electrons orbiting the nucleus is given an extra boost of energy so that it's barely still attached, you get a much larger Rydberg atom. Booth <jats:italic>et al.</jats:italic> created an even more exotic species: a giant molecule consisting of a regular cesium atom bound within a Rydberg atom of the same element. The molecules are named “trilobites” because their electronic density visually resembles fossils of these extinct marine creatures. </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="6230" page="99" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1260722">99</jats:related-article> </jats:p>

<jats:title>Additive explanation for anti-wear</jats:title> <jats:p> Additives in oil are vital for protecting engines from wear by forming films at sliding interfaces. Zinc dialkydithiophosphate (ZDDP) has been used for decades to reduce engine wear. Now there is a strong incentive for finding a replacement for ZDDP: Its breakdown products shorten catalytic converter lifetime. Gosvami <jats:italic>et al.</jats:italic> examined exactly how ZDDP produces an anti-wear film under high stress or elevated temperature (see the Perspective by Schwarz). Understanding these mechanisms will help in the development of higher-performance and more effective additives. </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="6230" page="102" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1258788">102</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6230" page="40" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa3276">40</jats:related-article> </jats:p>

<jats:title>Probing the nature of an exotic magnet</jats:title> <jats:p> To minimize their energy, materials with magnetic interactions tend to become ordered at low temperatures. However, if the magnetism is frustrated (for example, if the geometry of the crystal lattice gets in the way of minimizing the energy), the material may not reach an ordered state even at very low temperatures. Hirschberger <jats:italic>et al.</jats:italic> studied the excitations of such a system—the pyrochlore compound Tb <jats:sub>2</jats:sub> Ti <jats:sub>2</jats:sub> O <jats:sub>7</jats:sub> —using thermal transport measurements. Thermal conductivity at very low temperatures resembled that of a disordered metal; a puzzling finding in an electrically insulating transparent material. </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="6230" page="106" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1257340">106</jats:related-article> </jats:p>