TY - JOUR AB - Reducing defects boosts room-temperature performance of a thermoelectric device AU - Navita, Navita AU - Ibáñez, Maria ID - 15166 IS - 6688 JF - Science SN - 0036-8075 TI - Electron highways are cooler VL - 383 ER - TY - JOUR AB - Quantum entanglement is a key resource in currently developed quantum technologies. Sharing this fragile property between superconducting microwave circuits and optical or atomic systems would enable new functionalities, but this has been hindered by an energy scale mismatch of >104 and the resulting mutually imposed loss and noise. In this work, we created and verified entanglement between microwave and optical fields in a millikelvin environment. Using an optically pulsed superconducting electro-optical device, we show entanglement between propagating microwave and optical fields in the continuous variable domain. This achievement not only paves the way for entanglement between superconducting circuits and telecom wavelength light, but also has wide-ranging implications for hybrid quantum networks in the context of modularization, scaling, sensing, and cross-platform verification. AU - Sahu, Rishabh AU - Qiu, Liu AU - Hease, William J AU - Arnold, Georg M AU - Minoguchi, Y. AU - Rabl, P. AU - Fink, Johannes M ID - 13106 IS - 6646 JF - Science KW - Multidisciplinary SN - 0036-8075 TI - Entangling microwaves with light VL - 380 ER - TY - JOUR AB - In nature, proteins that switch between two conformations in response to environmental stimuli structurally transduce biochemical information in a manner analogous to how transistors control information flow in computing devices. Designing proteins with two distinct but fully structured conformations is a challenge for protein design as it requires sculpting an energy landscape with two distinct minima. Here we describe the design of “hinge” proteins that populate one designed state in the absence of ligand and a second designed state in the presence of ligand. X-ray crystallography, electron microscopy, double electron-electron resonance spectroscopy, and binding measurements demonstrate that despite the significant structural differences the two states are designed with atomic level accuracy and that the conformational and binding equilibria are closely coupled. AU - Praetorius, Florian M AU - Leung, Philip J. Y. AU - Tessmer, Maxx H. AU - Broerman, Adam AU - Demakis, Cullen AU - Dishman, Acacia F. AU - Pillai, Arvind AU - Idris, Abbas AU - Juergens, David AU - Dauparas, Justas AU - Li, Xinting AU - Levine, Paul M. AU - Lamb, Mila AU - Ballard, Ryanne K. AU - Gerben, Stacey R. AU - Nguyen, Hannah AU - Kang, Alex AU - Sankaran, Banumathi AU - Bera, Asim K. AU - Volkman, Brian F. AU - Nivala, Jeff AU - Stoll, Stefan AU - Baker, David ID - 14281 IS - 6659 JF - Science SN - 0036-8075 TI - Design of stimulus-responsive two-state hinge proteins VL - 381 ER - TY - JOUR AB - The hydrogen-rich outer layers of massive stars can be removed by interactions with a binary companion. Theoretical models predict that this stripping produces a population of hot helium stars of ~2 to 8 solar masses (M☉), however, only one such system has been identified thus far. We used ultraviolet photometry to identify potential stripped helium stars then investigated 25 of them using optical spectroscopy. We identified stars with high temperatures (~60,000 to 100,000 kelvin), high surface gravities, and hydrogen-depleted surfaces; 16 stars also showed binary motion. These properties match expectations for stars with initial masses of 8 to 25 M☉ that were stripped by binary interaction. Their masses fall in the gap between subdwarf helium stars and Wolf-Rayet stars. We propose that these stars could be progenitors of stripped-envelope supernovae. AU - Drout, M. R. AU - Götberg, Ylva Louise Linsdotter AU - Ludwig, B. A. AU - Groh, J. H. AU - de Mink, S. E. AU - O’Grady, A. J. G. AU - Smith, N. ID - 15085 IS - 6676 JF - Science KW - Stellar Astrophysics SN - 0036-8075 TI - An observed population of intermediate-mass helium stars that have been stripped in binaries VL - 382 ER - TY - JOUR AB - If you mix fruit syrups with alcohol to make a schnapps, the two liquids will remain perfectly blended forever. But if you mix oil with vinegar to make a vinaigrette, the oil and vinegar will soon separate back into their previous selves. Such liquid-liquid phase separation is a thermodynamically driven phenomenon and plays an important role in many biological processes (1). Although energy injection at the macroscale can reverse the phase separation—a strong shake is the normal response to a separated vinaigrette—little is known about the effect of energy added at the microscopic level on phase separation. This fundamental question has deep ramifications, notably in biology, because active processes also make the interior of a living cell different from a dead one. On page 768 of this issue, Adkins et al. (2) examine how mechanical activity at the microscopic scale affects liquid-liquid phase separation and allows liquids to climb surfaces. AU - Palacci, Jérémie A ID - 11996 IS - 6607 JF - Science SN - 0036-8075 TI - A soft active matter that can climb walls VL - 377 ER - TY - JOUR AB - Cells migrate through crowded microenvironments within tissues during normal development, immune response, and cancer metastasis. Although migration through pores and tracks in the extracellular matrix (ECM) has been well studied, little is known about cellular traversal into confining cell-dense tissues. We find that embryonic tissue invasion by Drosophila macrophages requires division of an epithelial ectodermal cell at the site of entry. Dividing ectodermal cells disassemble ECM attachment formed by integrin-mediated focal adhesions next to mesodermal cells, allowing macrophages to move their nuclei ahead and invade between two immediately adjacent tissues. Invasion efficiency depends on division frequency, but reduction of adhesion strength allows macrophage entry independently of division. This work demonstrates that tissue dynamics can regulate cellular infiltration. AU - Akhmanova, Maria AU - Emtenani, Shamsi AU - Krueger, Daniel AU - György, Attila AU - Pereira Guarda, Mariana AU - Vlasov, Mikhail AU - Vlasov, Fedor AU - Akopian, Andrei AU - Ratheesh, Aparna AU - De Renzis, Stefano AU - Siekhaus, Daria E ID - 10713 IS - 6591 JF - Science SN - 0036-8075 TI - Cell division in tissues enables macrophage infiltration VL - 376 ER - TY - JOUR AB - Russia’s unprovoked attack on Ukraine has destroyed civilian infrastructure, including universities, research centers, and other academic infrastructure (1). Many Ukrainian scholars and researchers remain in Ukraine, and their work has suffered from major setbacks (2–4). We call on international scientists and institutions to support them. AU - Chhugani, Karishma AU - Frolova, Alina AU - Salyha, Yuriy AU - Fiscutean, Andrada AU - Zlenko, Oksana AU - Reinsone, Sanita AU - Wolfsberger, Walter W. AU - Ivashchenko, Oleksandra V. AU - Maci, Megi AU - Dziuba, Dmytro AU - Parkhomenko, Andrii AU - Bortz, Eric AU - Kondrashov, Fyodor AU - Łabaj, Paweł P. AU - Romero, Veronika AU - Hlávka, Jakub AU - Oleksyk, Taras K. AU - Mangul, Serghei ID - 12116 IS - 6626 JF - Science SN - 0036-8075 TI - Remote opportunities for scholars in Ukraine VL - 378 ER - TY - JOUR AB - Asymmetric multiprotein complexes that undergo subunit exchange play central roles in biology but present a challenge for design because the components must not only contain interfaces that enable reversible association but also be stable and well behaved in isolation. We use implicit negative design to generate β sheet–mediated heterodimers that can be assembled into a wide variety of complexes. The designs are stable, folded, and soluble in isolation and rapidly assemble upon mixing, and crystal structures are close to the computational models. We construct linearly arranged hetero-oligomers with up to six different components, branched hetero-oligomers, closed C4-symmetric two-component rings, and hetero-oligomers assembled on a cyclic homo-oligomeric central hub and demonstrate that such complexes can readily reconfigure through subunit exchange. Our approach provides a general route to designing asymmetric reconfigurable protein systems. AU - Sahtoe, Danny D. AU - Praetorius, Florian M AU - Courbet, Alexis AU - Hsia, Yang AU - Wicky, Basile I. M. AU - Edman, Natasha I. AU - Miller, Lauren M. AU - Timmermans, Bart J. R. AU - Decarreau, Justin AU - Morris, Hana M. AU - Kang, Alex AU - Bera, Asim K. AU - Baker, David ID - 14282 IS - 6578 JF - Science SN - 0036-8075 TI - Reconfigurable asymmetric protein assemblies through implicit negative design VL - 375 ER - TY - JOUR AB - Electrons in moiré flat band systems can spontaneously break time-reversal symmetry, giving rise to a quantized anomalous Hall effect. In this study, we use a superconducting quantum interference device to image stray magnetic fields in twisted bilayer graphene aligned to hexagonal boron nitride. We find a magnetization of several Bohr magnetons per charge carrier, demonstrating that the magnetism is primarily orbital in nature. Our measurements reveal a large change in the magnetization as the chemical potential is swept across the quantum anomalous Hall gap, consistent with the expected contribution of chiral edge states to the magnetization of an orbital Chern insulator. Mapping the spatial evolution of field-driven magnetic reversal, we find a series of reproducible micrometer-scale domains pinned to structural disorder. AU - Tschirhart, C. L. AU - Serlin, M. AU - Polshyn, Hryhoriy AU - Shragai, A. AU - Xia, Z. AU - Zhu, J. AU - Zhang, Y. AU - Watanabe, K. AU - Taniguchi, T. AU - Huber, M. E. AU - Young, A. F. ID - 10616 IS - 6548 JF - Science KW - multidisciplinary SN - 0036-8075 TI - Imaging orbital ferromagnetism in a moiré Chern insulator VL - 372 ER - TY - JOUR AB - Genomes of germ cells present an existential vulnerability to organisms because germ cell mutations will propagate to future generations. Transposable elements are one source of such mutations. In the small flowering plant Arabidopsis, Long et al. found that genome methylation in the male germline is directed by small interfering RNAs (siRNAs) imperfectly transcribed from transposons (see the Perspective by Mosher). These germline siRNAs silence germline transposons and establish inherited methylation patterns in sperm, thus maintaining the integrity of the plant genome across generations. AU - Long, Jincheng AU - Walker, James AU - She, Wenjing AU - Aldridge, Billy AU - Gao, Hongbo AU - Deans, Samuel AU - Vickers, Martin AU - Feng, Xiaoqi ID - 12187 IS - 6550 JF - Science KW - Multidisciplinary SN - 0036-8075 TI - Nurse cell--derived small RNAs define paternal epigenetic inheritance in Arabidopsis VL - 373 ER -