Catálogo de publicaciones - revistas

<jats:title>A new tilt on predicting future ENSO variability</jats:title> <jats:p>A new finding should improve the ability of climate models to predict the behavior of the El Niño–Southern Oscillation (ENSO) in a warmer future. Ford et al. looked at the distribution of surface and subsurface temperatures in the eastern and western equatorial Pacific 19,000 years ago and between 3000 and 6000 years ago. Temperatures fluctuated over a greater range during the older period. ENSO thus depended more on the tilt of the equatorial Pacific thermocline than on the east-to-west temperature gradient, as previously thought.</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="6219" page="255" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1258437">255</jats:related-article> </jats:p>

<jats:title>Fluctuations revealed in fossil forests</jats:title> <jats:p> The reconstruction of past vegetation unlocks the door to understanding ecological changes associated with climatic change. But it is also difficult. Dunn <jats:italic>et al.</jats:italic> developed a method for assessing changes in vegetation openness based on epidermal cell morphology from conserved plant tissue. Applying this method to fossil assemblages from Patagonia, they show how vegetation structure changed over the Cenozoic era (49 to 11 million years ago). These changes map onto the known climate changes over this period and can also be used to track how the evolution of herbivorous mammals responded to vegetation structure. </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="6219" page="258" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1260947">258</jats:related-article> </jats:p>

<jats:title>Women's participation and attitudes to talent</jats:title> <jats:p> Some scientific disciplines have lower percentages of women in academia than others. Leslie <jats:italic>et al.</jats:italic> hypothesized that general attitudes about the discipline would reflect the representation of women in those fields (see the Perspective by Penner). Surveys revealed that some fields are believed to require attributes such as brilliance and genius, whereas other fields are believed to require more empathy or hard work. In fields where people thought that raw talent was required, academic departments had lower percentages of women. </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="6219" page="262" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1261375">262</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6219" page="234" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa3781">234</jats:related-article> </jats:p>

<jats:title>Turning viral persistence on and off</jats:title> <jats:p> Norovirus causes &gt;90% of the world's gastroenteritis. Norovirus can establish persistent infections, which may contribute to its spread. How does norovirus establish itself as a permanentw resident of the gut and how can such persistent infections be cured (see the Perspective by Wilks and Golovkina)? Baldridge <jats:italic>et al.</jats:italic> studied mice persistently infected with norovirus and found that viral persistence required the gut microbiota: resident bacteria in the gastrointestinal tract. Antibiotics prevented persistent mouse norovirus infection in a way that depended on the secreted antiviral protein interferon λ (IFN-λ). Nice <jats:italic>et al.</jats:italic> report that IFN-λ can cure mice persistently infected with norovirus, independent of the adaptive immune 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="6219" page="266" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1258025">266</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6219" page="269" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1258100">269</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6219" page="233" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa5056">233</jats:related-article> </jats:p>

<jats:title>Turning viral persistence on and off</jats:title> <jats:p> Norovirus causes &gt;90% of the world's gastroenteritis. Norovirus can establish persistent infections, which may contribute to its spread. How does norovirus establish itself as a permanentw resident of the gut and how can such persistent infections be cured (see the Perspective by Wilks and Golovkina)? Baldridge <jats:italic>et al.</jats:italic> studied mice persistently infected with norovirus and found that viral persistence required the gut microbiota: resident bacteria in the gastrointestinal tract. Antibiotics prevented persistent mouse norovirus infection in a way that depended on the secreted antiviral protein interferon λ (IFN-λ). Nice <jats:italic>et al.</jats:italic> report that IFN-λ can cure mice persistently infected with norovirus, independent of the adaptive immune 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="6219" page="266" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1258025">266</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6219" page="269" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1258100">269</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6219" page="233" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa5056">233</jats:related-article> </jats:p>

<jats:title>Cancer's alternative means to an end</jats:title> <jats:p> To stay alive and proliferating, tumor cells must maintain their telomeres: the DNA sequences at the ends of chromosomes. The majority accomplish this by activating the enzyme telomerase. However, certain tumor types favor a different mechanism called alternative lengthening of telomeres (ALT), which involves DNA recombination. Flynn <jats:italic>et al.</jats:italic> delineated the molecular events that occur at the telomeres of ALT-proficient tumor cells by studying the function of a protein that is altered by mutation in these tumors. The analysis revealed a specific protein kinase that is essential for ALT, which could in principle be targeted to halt tumor growth. </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="6219" page="273" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1257216">273</jats:related-article> </jats:p>

<jats:title> For vaccines, CD4 <jats:sup>+</jats:sup> T cells can spell trouble </jats:title> <jats:p> The ideal vaccine elicits immune memory—either antibodies or memory T cells—to protect the host from subsequent infections. T cell–mediated immunity requires both helper CD4 <jats:sup>+</jats:sup> T cells and cytotoxic CD8 <jats:sup>+</jats:sup> T cells to kill virus-infected cells. But what happens when a vaccine only elicits CD4 <jats:sup>+</jats:sup> memory T cells? Penaloza-MacMaster <jats:italic>et al.</jats:italic> probed this question by giving mice a vaccine that generated only memory CD4 <jats:sup>+</jats:sup> T cells against lymphocytic choriomeningitis virus (LCMV). Instead of protecting mice against chronic LCMV, vaccinated mice developed massive inflammation and died. Virus-specific CD8 <jats:sup>+</jats:sup> T cells or antibodies protected mice from the pathology. These results may have implications for vaccines against chronic viruses such as HIV. </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="6219" page="278" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa2148">278</jats:related-article> </jats:p>

<jats:title>Tunnel through and emit coherently</jats:title> <jats:p> The generation of coherent light (lasers and masers) forms the basis of a large optics industry. Liu <jats:italic>et al.</jats:italic> demonstrate a type of laser that is driven by the tunneling of single electrons in semiconductor double-quantum dots. Distinct from other existing semiconductor lasers, the emission mechanism is driven by tunneling of single charges between discrete energy levels that are electrically tunable. The ability to tune the levels by single-electron charging would allow their laser (or maser) to be turned on and off rapidly. </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="6219" page="285" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa2501">285</jats:related-article> </jats:p>

<jats:title>Nailing down graphene's topology</jats:title> <jats:p> An electron traveling along a closed path in the momentum space of the graphene crystal lattice may not end up exactly the way it started. If its path happens to include one of the special points in momentum space, it will acquire a phase shift. Physicists can detect the signatures of this process by studying the transport properties of graphene. Duca <jats:italic>et al.</jats:italic> used interferometry to directly measure this so-called Berry flux in a hexagonal optical lattice, where intersecting laser beams simulate the environment that electrons experience in graphene (see the Perspective by Lamacraft). The high-precision technique may be useful in characterizing other topological structures. </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="6219" page="288" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.1259052">288</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6219" page="232" related-article-type="in-this-issue" vol="347" xlink:href="10.1126/science.aaa4201">232</jats:related-article> </jats:p>