Catálogo de publicaciones - revistas

<jats:title>Revealing behavioral secrets in extinct species</jats:title> <jats:p> Extinct species had complex behaviors, just like modern species, but fossils generally reveal little of these details. New approaches that allow for the study of structures that relate directly to behavior are greatly improving our understanding of the lifestyles of extinct animals (see the Perspective by Witmer). Hanson <jats:italic>et al.</jats:italic> looked at three-dimensional scans of archosauromorph inner ears and found clear patterns relating these bones to complex movement, including flight. Choiniere <jats:italic>et al.</jats:italic> looked at inner ears and scleral eye rings and found a clear emergence of patterns relating to nocturnality in early theropod evolution. Together, these papers reveal behavioral complexity and evolutionary patterns in these groups. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="601" related-article-type="in-this-issue" vol="372">601</jats:related-article> , p. <jats:related-article issue="6542" page="610" related-article-type="in-this-issue" vol="372">610</jats:related-article> ; see also p. <jats:related-article issue="6542" page="575" related-article-type="in-this-issue" vol="372">575</jats:related-article> </jats:p>

<jats:title>Revealing behavioral secrets in extinct species</jats:title> <jats:p> Extinct species had complex behaviors, just like modern species, but fossils generally reveal little of these details. New approaches that allow for the study of structures that relate directly to behavior are greatly improving our understanding of the lifestyles of extinct animals (see the Perspective by Witmer). Hanson <jats:italic>et al.</jats:italic> looked at three-dimensional scans of archosauromorph inner ears and found clear patterns relating these bones to complex movement, including flight. Choiniere <jats:italic>et al.</jats:italic> looked at inner ears and scleral eye rings and found a clear emergence of patterns relating to nocturnality in early theropod evolution. Together, these papers reveal behavioral complexity and evolutionary patterns in these groups. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="601" related-article-type="in-this-issue" vol="372">601</jats:related-article> , p. <jats:related-article issue="6542" page="610" related-article-type="in-this-issue" vol="372">610</jats:related-article> ; see also p. <jats:related-article issue="6542" page="575" related-article-type="in-this-issue" vol="372">575</jats:related-article> </jats:p>

<jats:title>Reversible fiber fusion and fission</jats:title> <jats:p> Materials that can cycle between states are of interest for actuators, soft robotics, or recoverable membranes for separations. Chang <jats:italic>et al.</jats:italic> show that a collection of graphene oxide fibers can fuse into a single stronger fiber upon immersion in a solvent, extraction, and drying under tension (see the Perspective by Cruz-Silva and Elías). The geometrical deformation of the fibers during drying and swelling plays an important role in the reversible cycles, with a large volume change between the dried and swelled fibers. Moreover, fibers made from polymers, glass, metal, or silk can be given these abilities when coated with a micron-sized layer of graphene oxide. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="614" related-article-type="in-this-issue" vol="372">614</jats:related-article> ; see also p. <jats:related-article issue="6542" page="573" related-article-type="in-this-issue" vol="372">573</jats:related-article> </jats:p>

<jats:title>Tougher solar cell interfaces</jats:title> <jats:p> The low formation energies of the active layers in perovskite solar cells lead to low-toughness materials that are compliant and soft, which limits their interface stability and long-term reliability. Dai <jats:italic>et al.</jats:italic> show that treatment with iodine-terminated self-assembled monolayers that react with surface hydroxyl groups (which ultimately creates unwanted charge traps and voids) leads to a 50% increase of adhesion toughness between the electron transport layer and a mixed-composition perovskite thin film. The projected point at which 80% of the operating efficiency in perovskite solar cells was still retained increased from ∼700 to 4000 hours for 1-sun exposure with continuous maximum power point tracking. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="618" related-article-type="in-this-issue" vol="372">618</jats:related-article> </jats:p>

<jats:title>Quantum entanglement goes large</jats:title> <jats:p> Quantum entanglement occurs when two separate entities become strongly linked in a way that cannot be explained by classical physics; it is a powerful resource in quantum communication protocols and advanced technologies that aim to exploit the enhanced capabilities of quantum systems. To date, entanglement has generally been limited to microscopic quantum units such as pairs or multiples of single ions, atoms, photons, and so on. Kotler <jats:italic>et al.</jats:italic> and Mercier de Lépinay <jats:italic>et al.</jats:italic> demonstrate the ability to extend quantum entanglement to massive macroscopic systems (see the Perspective by Lau and Clerk). Entanglement of two mechanical oscillators on such a large length and mass scale is expected to find widespread use in both applications and fundamental physics to probe the boundary between the classical and quantum worlds. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="622" related-article-type="in-this-issue" vol="372">622</jats:related-article> , p. <jats:related-article issue="6542" page="625" related-article-type="in-this-issue" vol="372">625</jats:related-article> ; see also p. <jats:related-article issue="6542" page="570" related-article-type="in-this-issue" vol="372">570</jats:related-article> </jats:p>

<jats:title>Quantum entanglement goes large</jats:title> <jats:p> Quantum entanglement occurs when two separate entities become strongly linked in a way that cannot be explained by classical physics; it is a powerful resource in quantum communication protocols and advanced technologies that aim to exploit the enhanced capabilities of quantum systems. To date, entanglement has generally been limited to microscopic quantum units such as pairs or multiples of single ions, atoms, photons, and so on. Kotler <jats:italic>et al.</jats:italic> and Mercier de Lépinay <jats:italic>et al.</jats:italic> demonstrate the ability to extend quantum entanglement to massive macroscopic systems (see the Perspective by Lau and Clerk). Entanglement of two mechanical oscillators on such a large length and mass scale is expected to find widespread use in both applications and fundamental physics to probe the boundary between the classical and quantum worlds. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="622" related-article-type="in-this-issue" vol="372">622</jats:related-article> , p. <jats:related-article issue="6542" page="625" related-article-type="in-this-issue" vol="372">625</jats:related-article> ; see also p. <jats:related-article issue="6542" page="570" related-article-type="in-this-issue" vol="372">570</jats:related-article> </jats:p>

<jats:title>A role for vacancies</jats:title> <jats:p> Hafnia-based materials are of interest because of their potential use in microelectronic components. Hafnia-oxide is a ferroelectric material, but whether the polarization switching comes from the polar crystal phases or the migration of oxygen vacancies has remained an open question. Nukala <jats:italic>et al.</jats:italic> attempted to resolve this controversy by conducting electron microscopy during the operation of a hafnium zirconium oxide capacitor. The authors found that vacancy migration is intertwined with the ferroelectric switching, which has implications for the use of these materials in a range of microelectronic applications. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="630" related-article-type="in-this-issue" vol="372">630</jats:related-article> </jats:p>

<jats:title>The Slovakian test case</jats:title> <jats:p> Toward the end of 2020, Slovakia decided that it would test and then isolate positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cases among its entire population of ∼5.5 million, and more than 50,000 positive cases were found during a rapid antigen testing campaign. Pavelka <jats:italic>et al.</jats:italic> analyzed the data and found that in 41 counties before and after the two rounds of testing, infection prevalence declined by about 80% (see the Perspective by García-Fiñana and Buchan). They also used the data to test a microsimulation model for one county. Quarantine of the whole household after a positive test was essential to achieving a large reduction in prevalence. Since Autumn 2020, transmission in Slovakia has rebounded, despite other interventions, because high-intensity testing was not sustainable. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="635" related-article-type="in-this-issue" vol="372">635</jats:related-article> ; see also p. <jats:related-article issue="6542" page="571" related-article-type="in-this-issue" vol="372">571</jats:related-article> </jats:p>

<jats:title>A large-scale screen to target SARS-CoV-2</jats:title> <jats:p> The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome is initially expressed as two large polyproteins. Its main protease, M <jats:sup>pro</jats:sup> , is essential to yield functional viral proteins, making it a key drug target. Günther <jats:italic>et al.</jats:italic> used x-ray crystallography to screen more than 5000 compounds that are either approved drugs or drugs in clinical trials. The screen identified 37 compounds that bind to M <jats:sup>pro</jats:sup> . High-resolution structures showed that most compounds bind at the active site but also revealed two allosteric sites where binding of a drug causes conformational changes that affect the active site. In cell-based assays, seven compounds had antiviral activity without toxicity. The most potent, calpeptin, binds covalently in the active site, whereas the second most potent, pelitinib, binds at an allosteric site. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="642" related-article-type="in-this-issue" vol="372">642</jats:related-article> </jats:p>

<jats:title>High fliers</jats:title> <jats:p> Migrating from hemisphere to hemisphere is a global strategy for many bird species. Despite allowing birds to track productivity, these long-distance movements bring them in contact with inhospitable regions such as deserts and oceans. Sjöberg <jats:italic>et al.</jats:italic> used geolocators to monitor flight in great reed warblers ( <jats:italic>Acrocephalus arundinaceus</jats:italic> ) and found that when over these types of regions, this normally nocturnal migrating species flew both day and night. During the day, the birds increased the altitudes at which they flew, rising to more than 5000 meters. Such behavior may allow them to avoid heat stress or other daytime threats during migration. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article issue="6542" page="646" related-article-type="in-this-issue" vol="372">646</jats:related-article> </jats:p>