Catálogo de publicaciones - revistas

<jats:p> Neuronal precursor cells of the vertebrate central nervous system shed an apical end-foot to differentiate. <jats:named-content content-type="related-content"> [Also see Report by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="200" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1247521">Das and Storey</jats:related-article> ] </jats:named-content> </jats:p>

<jats:p> A chronic autoimmune disease sometimes appears coincidently in patients with cancer. <jats:named-content content-type="related-content"> [Also see Research Article by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="152" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246886"> Joseph <jats:italic>et al.</jats:italic> </jats:related-article> ] </jats:named-content> </jats:p>

<jats:p> Recent observations with the Hubble Space Telescope reveal what are probably eruptions of water vapor from Jupiter's moon Europa. <jats:named-content content-type="related-content"> [Also see Report by <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="171" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1247051"> Roth <jats:italic>et al.</jats:italic> </jats:related-article> ] </jats:named-content> </jats:p>

<jats:p>A great world leader and humanitarian fought for racial equality, human rights, science education, and the rights of AIDS patients.</jats:p>

<jats:title>Cancer Immunosurveillance Gone Bad?</jats:title> <jats:p> A subset of patients who develop scleroderma, a debilitating autoimmune disease, have an elevated risk of developing cancer. These patients harbor autoantibodies to RPC1, an RNA polymerase subunit encoded by the <jats:italic>POLR3A</jats:italic> gene. <jats:bold> Joseph <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="152" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246886">152</jats:related-article> , published online December 5; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="147" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1249486">Teng and Smyth</jats:related-article> </jats:bold> ) explored whether the RPC1 autoantibodies target a “foreign” antigen derived from a mutated <jats:italic>POLR3A</jats:italic> gene. Sequence analysis revealed that <jats:italic>POLR3A</jats:italic> mutations were present in tumors from six of eight patients with RPC1 autoantibodies but in no tumors from eight control patients who lacked RPC1 autoantibodies. Cell culture data suggested that the <jats:italic>POLR3A</jats:italic> mutations triggered cellular and humoral immune responses in the patients. These results provide support for the “immunosurveillance” hypothesis, which posits the continual eradication of nascent tumor cells via immune responses. </jats:p>

<jats:title>Collective Coherent Spin Dynamics</jats:title> <jats:p> Ultracold gases have shown considerable promise for the quantum simulation of more complicated systems, such as correlated electrons in solids. Usually, researchers use two hyperfine states of the atoms to correspond to the spin up and down states of the electrons; however, these gases typically have a much richer internal state structure. <jats:bold> Krauser <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="157" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1244059">157</jats:related-article> ) observed the coherent behavior of a gas of potassium-40 atoms that had 10 accessible internal spin states and that evolved through collisions. The spin state of the system oscillated as a whole, a surprising finding given that the atoms are fermions. </jats:p>

<jats:title>Computational Metamaterials</jats:title> <jats:p> Optical signal processing of light waves can represent certain mathematical functions and perform computational tasks on signals or images in an analog fashion. However, the complex systems of lenses and filters required are bulky. Metamaterials can perform similar optical processing operations but with materials that need only be a wavelength thick. <jats:bold> Silva <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="160" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1242818">160</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="6167" page="144" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1248659">Sihvola</jats:related-article> </jats:bold> ) present a simulation study that shows how an architecture based on such metamaterials can be designed to perform a suite of mathematical functions to create ultrathin optical signal and data processors. </jats:p>

<jats:title>Heteroepitaxy Writ Thin</jats:title> <jats:p> A common method for creating a thin single-crystal layer of a semiconductor for use in an electronic device is heteroepitaxy—growing the layer on the face of a single crystal of a different material that acts as a template for assembly. <jats:bold> Liu <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="163" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246137">163</jats:related-article> ) now describe a similar process in which the edge of a graphene layer that was grown on a copper surface directs the assembly of a monolayer of hexagonal boron nitride. The boron nitride grew from inside edge of holes created in the graphene layer. The interface and the relative orientation of the two layers were determined by a variety of scanning microscopy and surface diffraction techniques. </jats:p>

<jats:title>Soft, Selective CO Sorption</jats:title> <jats:p> Many industrial processes produce CO, which could be used as a chemical feedstock, but separation of CO from other gases, especially N <jats:sub>2</jats:sub> , is too difficult to be economically viable. <jats:bold> Sato <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="167" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1246423">167</jats:related-article> , published online 12 December 2013) now report that a porous coordination polymer containing Cu <jats:sup>2+</jats:sup> ions can selectivity bind CO through serial structural changes reminiscent of allosteric effects in proteins. The separation of CO-N <jats:sub>2</jats:sub> mixtures can be achieved with a low input energy for CO desorption. </jats:p>

<jats:title>Europa's Plumes</jats:title> <jats:p> Jupiter's moon Europa has a subsurface ocean and a relatively young icy surface. <jats:bold> Roth <jats:italic>et al.</jats:italic> </jats:bold> (p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="171" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1247051">171</jats:related-article> , published online 12 December 2013; see the Perspective by <jats:bold> <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6167" page="148" related-article-type="in-this-issue" vol="343" xlink:href="10.1126/science.1248879">Spencer</jats:related-article> </jats:bold> ) analyzed spectral images taken by the Hubble Space Telescope that show ultraviolet emissions from the moon's atmosphere, and report a statistically significant emission signal extending above the satellite's southern hemisphere. This emission is consistent with two 200-km-high plumes of water vapor. Tidal stresses likely play a role in opening and closing fractures at the surface. </jats:p>