Catálogo de publicaciones - revistas

<jats:title>Dog domestication was multifaceted</jats:title> <jats:p> Dogs were the first domesticated animal, likely originating from human-associated wolves, but their origin remains unclear. Bergstrom <jats:italic>et al.</jats:italic> sequenced 27 ancient dog genomes from multiple locations near to and corresponding in time to comparable human ancient DNA sites (see the Perspective by Pavlidis and Somel). By analyzing these genomes, along with other ancient and modern dog genomes, the authors found that dogs likely arose once from a now-extinct wolf population. They also found that at least five different dog populations ∼10,000 years before the present show replacement in Europe at later dates. Furthermore, some dog population genetics are similar to those of humans, whereas others differ, inferring a complex ancestral history for humanity's best friend. </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="6516" page="557" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.aba9572">557</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6516" page="522" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abe7823">522</jats:related-article> </jats:p>

<jats:title>A series of unfortunate events</jats:title> <jats:p> The history of how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread around the planet has been far from clear. Several narratives have been propagated by social media and, in some cases, national policies were forged in response. Now that many thousands of virus sequences are available, two studies analyzed some of the key early events in the spread of SARS-CoV-2. Bedford <jats:italic>et al.</jats:italic> found that the virus arrived in Washington state in late January or early February. The viral genome from the first case detected had mutations similar to those found in Chinese samples and rapidly spread and dominated subsequent undetected community transmission. The other viruses detected had origins in Europe. Worobey <jats:italic>et al.</jats:italic> found that early introductions into Germany and the west coast of the United States were extinguished by vigorous public health efforts, but these successes were largely unrecognized. Unfortunately, several major travel events occurred in February, including repatriations from China, with lax public health follow-up. Serial, independent introductions triggered the major outbreaks in the United States and Europe that still hold us in the grip of control measures. </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="6516" page="571" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abc0523">571</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6516" page="564" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abc8169">564</jats:related-article> </jats:p>

<jats:title>A series of unfortunate events</jats:title> <jats:p> The history of how severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread around the planet has been far from clear. Several narratives have been propagated by social media and, in some cases, national policies were forged in response. Now that many thousands of virus sequences are available, two studies analyzed some of the key early events in the spread of SARS-CoV-2. Bedford <jats:italic>et al.</jats:italic> found that the virus arrived in Washington state in late January or early February. The viral genome from the first case detected had mutations similar to those found in Chinese samples and rapidly spread and dominated subsequent undetected community transmission. The other viruses detected had origins in Europe. Worobey <jats:italic>et al.</jats:italic> found that early introductions into Germany and the west coast of the United States were extinguished by vigorous public health efforts, but these successes were largely unrecognized. Unfortunately, several major travel events occurred in February, including repatriations from China, with lax public health follow-up. Serial, independent introductions triggered the major outbreaks in the United States and Europe that still hold us in the grip of control measures. </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="6516" page="571" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abc0523">571</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6516" page="564" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abc8169">564</jats:related-article> </jats:p>

<jats:title>Songbirds reclaim favored frequencies</jats:title> <jats:p> When severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic lockdowns were instituted across entire countries, human activities ceased in an unprecedented way. Derryberry <jats:italic>et al.</jats:italic> found that the reduction in traffic sound in the San Francisco Bay Area of California to levels not seen for half a century led to a shift in song frequency in white-crowned sparrows (see the Perspective by Halfwerk). This shift was especially notable because the frequency of human-produced traffic noise occurs within a range that interferes with the highest performance and most effective song. Thus, our “quiet” allowed the birds to quickly fill the most effective song space. </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="6516" page="575" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abd5777">575</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6516" page="523" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abe8026">523</jats:related-article> </jats:p>

<jats:title>DNA analyses of an early East Asian</jats:title> <jats:p> Ancient, anatomically modern humans interbred with the archaic hominins Neanderthals and Denisovans. However, the extent of this interbreeding and how it affects modern populations is not well understood. Massilani <jats:italic>et al.</jats:italic> generated genome-wide data from a 34,000-year-old female individual from the Salkhit Valley in eastern Mongolia and conducted a detailed modeling of her ancestry with regard to other Pleistocene human genomes. They found evidence for Denisovan ancestry in ancient human genomes from at least 6000 years before the Salkhit individual lived and determined that the Denisovan contribution differed from that of another ancient Asian individual, as well as from the ancient Denisovan contribution to extant Australasians. This reference point helps us to understand the early history of our species in Eurasia, especially Eastern Eurasia, for which genomic evidence remains scarce. </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="6516" page="579" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abc1166">579</jats:related-article> </jats:p>

<jats:title>A timeline of cave dwellers in sediment</jats:title> <jats:p> Two archaic lineages overlapped with modern humans outside of Africa: the well-studied Neanderthals and their more mysterious cousins, the Denisovans. Denisovan remains are rare, being limited to Denisovan Cave in Siberia and a putative, undated jaw from Tibet. However, there is evidence for multiple introgressions from Denisovans into modern-day humans, especially in Australasian populations. By examining the sediment of Baishiya Karst Cave located on a high plateau in Tibet, Zhang <jats:italic>et al.</jats:italic> identified ancient mitochondrial DNA from Denisovans indicating their presence at about 100 thousand, 60 thousand, and possibly 45 thousand years ago. This finding provides insight into the timing and distribution of Denisovans in Asia and extends the time of occupation of the Tibetan plateau by hominins. </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="6516" page="584" related-article-type="in-this-issue" vol="370" xlink:href="10.1126/science.abb6320">584</jats:related-article> </jats:p>

<jats:title>Lightening the load</jats:title> <jats:p> Permanent magnets are generally produced from solid metals or alloys. Less dense compositions involving lighter elements tend to demagnetize well below room temperature or under modest applied external fields. Perlepe <jats:italic>et al.</jats:italic> now report that chemical reduction of a low-density chromium-pyrazine network produces a magnet that remains stable above 200°C and resists demagnetization with 7500-oersted coercivity at room temperature. The straightforward synthetic route to the material shows promise for broad exploration of potential applications. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6516" page="587" related-article-type="in-this-issue" vol="370">587</jats:related-article> </jats:p>

<jats:title>Addressing the many and the individual</jats:title> <jats:p> The ability to coherently manipulate the quantum state of atomic defects in solid-state systems is a promising route to developing a platform for quantum technologies. A successful platform requires the interaction of many qubits in close proximity, as well as the ability to address each qubit individually, and, to date, such requirements have run counter to each other. Chen <jats:italic>et al.</jats:italic> devised an optical frequency-domain method with which they were able to simultaneously address many individual rare-earth ion defects (six at this point) with separations all within the diffraction limit of the control light. Because the approach is scalable to tens or hundreds of defects, it provides the prospect of realizing truly large-scale quantum processors. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6516" page="592" related-article-type="in-this-issue" vol="370">592</jats:related-article> </jats:p>

<jats:title>Vacancies enhance proton conductivity</jats:title> <jats:p> Proton-exchange membranes (PEMs) allow for the transport of protons while acting as electrical insulators and ensuring that reactants are kept apart; therefore, they are a key component in devices such as low-temperature fuel cells. PEMs are typically made from polymers or materials embedded in a polymer matrix and need to operate in conditions of very high humidity. Starting with an inorganic, layered material, CdPS <jats:sub>3</jats:sub> , Qian <jats:italic>et al.</jats:italic> show that the removal of a small amount of cadmium introduces vacancies that greatly increase the proton conductivity of the PEMs (see the Perspective by Wang and He). The process works for manganese-based membranes as well, and high lithium ion transport was also observed. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6516" page="596" related-article-type="in-this-issue" vol="370">596</jats:related-article> ; see also p. <jats:related-article issue="6516" page="525" related-article-type="in-this-issue" vol="370">525</jats:related-article> </jats:p>

<jats:title>Polaritons with a twist</jats:title> <jats:p> The ability to design and fabricate optical systems with tunable topological features makes them especially attractive for developing analogs of topological condensed matter systems, which by themselves tend to be fixed or limited in their tunability. Liu <jats:italic>et al.</jats:italic> now show that the combination of a two-dimensional material with a photonic crystal can be used to develop an analogous quantum spin Hall system. The strong coupling between the monolayer tungsten disulfide excitons with a nontrivial hexagonal photonic crystal gives rise to helical topological polaritons observed at up to 200 kelvin. The topological polaritons can be actively tuned by temperature and may further be manipulated with electric or magnetic fields, thereby providing a flexible platform with which to explore exotic topological phenomena and new phases of quantum matter. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6516" page="600" related-article-type="in-this-issue" vol="370">600</jats:related-article> </jats:p>