Catálogo de publicaciones - revistas

<jats:title>New for old—TB drug development</jats:title> <jats:p> Tuberculosis (TB) is a global health threat for which there is only lengthy drug treatment. Patients need to consume multiple tablets over several months and frequently fail to complete their treatment. Consequently, drug-resistant strains of the pathogen have emerged, which add to the threat. Kling <jats:italic>et al.</jats:italic> revisited a natural product called griselimycin, extracted from the same organism that produced the prototype anti-TB drug, streptomycin. Unmodified griselimycin has poor pharmacological properties. However, one synthetic derivative had improved oral uptake and penetrated cells of the immune system that harbor the TB mycobacterium. In combination with other drugs, the griselimycin derivative showed high potency in mice with TB. </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="6239" page="1106" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa4690">1106</jats:related-article> </jats:p>

<jats:title>Visualizing ferroelectric domains</jats:title> <jats:p> Multiferroic materials support intertwined ferromagnetic and ferroelectric orders, with the magnetic field capable of controlling the electric order and vice versa. Matsubara <jats:italic>et al.</jats:italic> used second harmonic generation microscopy to visualize what happens to the ferroelectric domains in the multiferroic TbMnO <jats:sub>3</jats:sub> when an externally applied magnetic field changes the direction of electric polarization by 90°. Unexpectedly, the domain walls, initially parallel to the polarization vector, did not change their shape or position. The resulting transition from neutral to charged domain walls may help in the development of future ferroelectric devices. </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="6239" page="1112" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1260561">1112</jats:related-article> </jats:p>

<jats:title>A frigid simulator for friction</jats:title> <jats:p> Friction can be a friend or a foe, depending on whether we are trying to brake on a slippery road or to protect moving parts in industrial equipment. It results from the forces between atoms on the two surfaces in contact, but the details of the process are not well understood. Bylinskii <jats:italic>et al.</jats:italic> constructed a tunable friction simulator out of a handful of cold trapped ions that move in the potential of an optical lattice (see the Perspective by Meyer). They could vary the friction force experienced by the ions from maximal to nearly zero simply by changing the spatial arrangement of the ion array with respect to the optical lattice. </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="6239" page="1115" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1261422">1115</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6239" page="1089" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab3539">1089</jats:related-article> </jats:p>

<jats:title>Slip sliding away</jats:title> <jats:p> Many applications would benefit from ultralow friction conditions to minimize wear on the moving parts such as in hard drives or engines. On the very small scale, ultralow friction has been observed with graphite as a lubricant. Berman <jats:italic>et al.</jats:italic> achieved superlubricity using graphene in combination with crystalline diamond nanoparticles and diamondlike carbon (see the Perspective by Hone and Carpick). Simulations showed that sliding of the graphene patches around the tiny nanodiamond particles led to nanoscrolls with reduced contact area that slide easily against the amorphous diamondlike carbon surface. </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="6239" page="1118" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1262024">1118</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6239" page="1087" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab3233">1087</jats:related-article> </jats:p>

<jats:title>Standing at order</jats:title> <jats:p> Thin films of organic molecules on solid substrates tend to nucleate at many sites and grow multiple domains. However, one large uniform film would be much more desirable in device applications. Seiki <jats:italic>et al.</jats:italic> designed organic molecules that filled space in a hexagonal tiling; a propeller-like triptycene base adhered to crystalline surfaces and alkyl tails extended away from it. The authors could make well-ordered multilayer films up to centimeter length scales. </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="6239" page="1122" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab1391">1122</jats:related-article> </jats:p>

<jats:title>More N<jats:sub>2</jats:sub>O is no laughing matter</jats:title><jats:p>Because N<jats:sub>2</jats:sub>O is a potent greenhouse gas, tracking its sources and sinks—including those from natural processes—is imperative. Babbin<jats:italic>et al.</jats:italic>developed an isotopic tracer method to measure biological N<jats:sub>2</jats:sub>O reduction rates directly in the Eastern Tropical North Pacific Ocean. Incomplete denitrification results in the rapid cycling and net accumulation of N<jats:sub>2</jats:sub>O. As oxygen minimum zones expand in the global ocean, more N<jats:sub>2</jats:sub>O may enter the atmosphere than previously expected.</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="6239" page="1127" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa8380">1127</jats:related-article></jats:p>

<jats:title>Not getting all sides of the news?</jats:title> <jats:p> People are increasingly turning away from mass media to social media as a way of learning news and civic information. Bakshy <jats:italic>et al.</jats:italic> examined the news that millions of Facebook users' peers shared, what information these users were presented with, and what they ultimately consumed (see the Perspective by Lazer). Friends shared substantially less cross-cutting news from sources aligned with an opposing ideology. People encountered roughly 15% less cross-cutting content in news feeds due to algorithmic ranking and clicked through to 70% less of this cross-cutting content. Within the domain of political news encountered in social media, selective exposure appears to drive attention. </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="6239" page="1130" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa1160">1130</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6239" page="1090" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab1422">1090</jats:related-article> </jats:p>

<jats:title>Double trouble</jats:title><jats:p>It is well known that climate change will warm ocean waters, but dissolved oxygen levels also decrease as water warms. Deutsch<jats:italic>et al.</jats:italic>combined data on metabolism, temperature, and demographics to determine the impact of marine deoxygenation on a variety of fish and crustacean species (see the Perspective by Kleypas). Predicted climate and oxygen conditions can be expected to contract the distribution of marine fish poleward, as equatorward waters become too low in oxygen to support their energy needs. Furthermore, even the more-poleward waters will have reduced oxygen levels.</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="6239" page="1132" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aaa1605">1132</jats:related-article>; see also p.<jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6239" page="1086" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab4122">1086</jats:related-article></jats:p>

<jats:title>Not as deep</jats:title> <jats:p> As our climate warms, many species ranges are predicted to shift toward the warmer poles. Focusing solely on temperatures, however, ignores many factors that change across latitudes, such as the intensity of solar radiation. Muir <jats:italic>et al.</jats:italic> looked at global distributions of two groups of reef-building corals (see the Perspective by Kleypas). Most reef-building corals occur deep enough to be protected from surge. However, corals require sunlight to sustain their symbiotic photosynthetic algae. Because solar radiation is more limited farther away from the equator, future populations might be limited to more turbulent shallow waters. </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="6239" page="1135" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.1259911">1135</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6239" page="1086" related-article-type="in-this-issue" vol="348" xlink:href="10.1126/science.aab4122">1086</jats:related-article> </jats:p>