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Strain-hardening (the increase of flow stress with plastic strain) is the most important phenomenon in the mechanical behaviour of engineering alloys because it ensures that flow is delocalized, enhances tensile ductility and inhibits catastrophic mechanical failure 1 , 2 . Metallic glasses (MGs) lack the crystallinity of conventional engineering alloys, and some of their properties—such as higher yield stress and elastic strain limit 3 —are greatly improved relative to their crystalline counterparts. MGs can have high fracture toughness and have the highest known ‘damage tolerance’ (defined as the product of yield stress and fracture toughness) 4 among all structural materials. However, the use of MGs in structural applications is largely limited by the fact that they show strain-softening instead of strain-hardening; this leads to extreme localization of plastic flow in shear bands, and is associated with early catastrophic failure in tension. Although rejuvenation of an MG (raising its energy to values that are typical of glass formation at a higher cooling rate) lowers its yield stress, which might enable strain-hardening 5 , it is unclear whether sufficient rejuvenation can be achieved in bulk samples while retaining their glassy structure. Here we show that plastic deformation under triaxial compression at room temperature can rejuvenate bulk MG samples sufficiently to enable strain-hardening through a mechanism that has not been previously observed in the metallic state. This transformed behaviour suppresses shear-banding in bulk samples in normal uniaxial (tensile or compressive) tests, prevents catastrophic failure and leads to higher ultimate flow stress. The rejuvenated MGs are stable at room temperature and show exceptionally efficient strain-hardening, greatly increasing their potential use in structural applications. Bulk metallic glasses can acquire the ability to strain-harden through a mechanical rejuvenation treatment at room temperature that retains their non-crystalline structure.

A large repulsion between particles in a quantum system can lead to their localization, an effect responsible for the Mott insulator phases in strongly correlated materials. In a system with multiple orbitals, an orbital-selective Mott insulator can form, where electrons in some orbitals are predicted to localize while others remain itinerant. Here we demonstrate a more general version of this phenomenon by observing flavour-selective localization in an atom-based quantum simulator. Our experiment realizes Fermi–Hubbard models with an SU(3) symmetry that can be broken using a tunable coupling between flavours. We observe an enhancement of the localization associated with a selective Mott transition and the emergence of flavour-dependent correlations. Our realization of flavour-selective Mott physics demonstrates the potential of cold atoms to simulate interacting multicomponent materials such as superconductors and topological insulators. A Mott insulator forms when strong interactions between particles cause them to become localized. A cold atom simulator has now been used to realize a selective Mott insulator in which atoms are localized or propagating depending on their spin state.

The complex interaction between the Indian Ocean dipole (IOD) and El Niño–Southern Oscillation (ENSO) is further investigated in this study, with a focus on the impacts of the IOD on ENSO in the subsequent year [ENSO(+1)]. The interaction between the IOD and the concurrent ENSO [ENSO(0)] can be summarized as follows: ENSO(0) can trigger and enhance the IOD, while the IOD can enhance ENSO(0) and accelerate its demise. Regarding the impacts of IOD(0) on the subsequent ENSO(+1), it is revealed that the IOD can lead to anomalous SST cooling patterns over the equatorial Pacific after the winter following the IOD, indicating the formation of a La Niña–like pattern in the subsequent year. While the SST cooling tendency associated with a positive IOD is attributable primarily to net heat flux (thermodynamic processes) from autumn to the ensuing spring, after the ensuing spring the dominant contribution comes from oceanic processes (dynamic processes) instead. From autumn to the ensuing spring, the downward shortwave flux response contributes the most to SST cooling over the central and eastern Pacific, due to the cloud–radiation–SST feedback. From the ensuing winter to the ensuing summer, changes in latent heat flux (LHF) are important for SST cooling, indicating that the release of LHF from the ocean into the atmosphere increases due to strong evaporation and leads to SST cooling through the wind–evaporation–SST feedback. The wind stress response and thermocline shoaling verify that local Bjerknes feedback is crucial for the initiation of La Niña in the later stage.

It has long been known that males are more susceptible than females to hepatocellular carcinoma (HCC), but the reason remains elusive. In this study, we investigated the expression and function of the long noncoding RNA FTX (lnc-FTX), an X-inactive-specific transcript (XIST) regulator transcribed from the X chromosome inactivation center, in both HCC and HCC gender disparity. lnc-FTX is expressed at higher levels in female livers than in male livers and is significantly downregulated in HCC tissues compared with normal liver tissues. Patients with higher lnc-FTX expression exhibited longer survival, suggesting that lnc-FTX is a useful prognostic factor for HCC patients. lnc-FTX inhibits HCC cell growth and metastasis both in vitro and in vivo . Mechanistically, lnc-FTX represses Wnt/β-catenin signaling activity by competitively sponging miR-374a and inhibits HCC cell epithelial–mesenchymal transition and invasion. In addition, lnc-FTX binds to the DNA replication licensing factor MCM2, thereby impeding DNA replication and inhibiting proliferation in HCC cells. In conclusion, these findings suggest that lnc-FTX may act as a tumor suppressor in HCC through physically binding miR-374a and MCM2. It may also be one of the reasons for HCC gender disparity and may potentially contribute to HCC treatment.

Let p a be a prime power and n 0 a square-free number. We prove that any complementing pair in a cyclic group of order p a n 0 is quasi-periodic, with one component decomposable by the the subgroup of order p . The proof is by induction and reduction since the presence of the square-free factor n 0 allows us to perform a Tijdeman decomposition. We also give an explicit example to show that Z 72 is the smallest cyclic group that fails to have the strong Tijdeman property.

In the Hall effect, a voltage drop develops perpendicularly to the current flow in the presence of a magnetic field, leading to a transverse Hall resistance. Recent developments with quantum simulators have unveiled strongly correlated and universal manifestations of the Hall effect. However, a direct measurement of the Hall voltage and of the Hall resistance in a non-electronic system of strongly interacting fermions was not achieved to date. Here, we demonstrate a technique for measuring the Hall voltage in a neutral-atom-based quantum simulator. From that we provide the first direct measurement of the Hall resistance in a cold-atom analogue of a solid-state Hall bar and study its dependence on the carrier density, along with theoretical analyses. Our work closes a major gap between analogue quantum simulations and measurements performed in solid-state systems, providing a key tool for the exploration of the Hall effect in highly tunable and strongly correlated systems. The authors report an experimental study of the Hall effect measuring electrical quantities in ultracold fermionic quantum simulators. This provides a way forward in measuring transport properties in these platforms and verifying long-standing theoretical predictions.

An IoT-enabled innovative environment with efficient routing is proposed for digital library services to analyze user behavior. This conceptual framework leverages the Internet of Things (IoT) to create a smart library ecosystem where connected devices collect and share data in real-time. The emphasis on efficient routing ensures seamless access to digital resources, optimizing the user experience. This study introduces an IoT-enabled innovative environment aimed at optimizing digital library services by examining user behavior, incorporating the Clustered Centered Routing Cryptography Scheme (CCRCS). The proposed framework leverages the Internet of Things (IoT) to create a dynamic ecosystem within digital libraries, facilitating efficient data collection and analysis. By implementing the CCRCS, data transmission is secured through clustered-centered routing, ensuring the integrity and confidentiality of user interactions and resource access. Through the IoT infrastructure, libraries can monitor user behavior in real-time, capturing valuable insights into preferences, browsing patterns, and resource utilization. This holistic approach enables libraries to adapt their services to better meet user needs, optimize resource allocation, and enhance the overall user experience. The integration of IoT technologies with robust cryptographic protocols represents a significant advancement in digital library management, offering unparalleled opportunities for data-driven decision-making and personalized service delivery.

Capillary condensation of water is ubiquitous in nature and technology. It routinely occurs in granular and porous media, can strongly alter such properties as adhesion, lubrication, friction and corrosion, and is important in many processes used by microelectronics, pharmaceutical, food and other industries 1 – 4 . The century-old Kelvin equation 5 is frequently used to describe condensation phenomena and has been shown to hold well for liquid menisci with diameters as small as several nanometres 1 – 4 , 6 – 14 . For even smaller capillaries that are involved in condensation under ambient humidity and so of particular practical interest, the Kelvin equation is expected to break down because the required confinement becomes comparable to the size of water molecules 1 – 22 . Here we use van der Waals assembly of two-dimensional crystals to create atomic-scale capillaries and study condensation within them. Our smallest capillaries are less than four ångströms in height and can accommodate just a monolayer of water. Surprisingly, even at this scale, we find that the macroscopic Kelvin equation using the characteristics of bulk water describes the condensation transition accurately in strongly hydrophilic (mica) capillaries and remains qualitatively valid for weakly hydrophilic (graphite) ones. We show that this agreement is fortuitous and can be attributed to elastic deformation of capillary walls 23 – 25 , which suppresses the giant oscillatory behaviour expected from the commensurability between the atomic-scale capillaries and water molecules 20 , 21 . Our work provides a basis for an improved understanding of capillary effects at the smallest scale possible, which is important in many realistic situations. In the tiniest of capillaries, barely larger than a water molecule, condensation is surprisingly predictable from the macroscopic Kelvin condensation equation, a coincidence partially owing to elastic deformation of the capillary walls.

Key Points Large-scale mapping of chromatin features has emerged as a powerful tool to understand the global landscape of genome regulation. In particular, chromatin immunoprecipitation followed by sequencing (ChIP–seq) has generated vast amounts of data on the genome-wide distribution of histone modifications across various cell types. Eukaryotic chromatin structure can be viewed as superimposed organizational layers, from DNA sequence, to nucleosomes, to histone modifications and variants and, finally, to higher-order structures. Histone modifications demarcate functional elements, including promoters, gene bodies, enhancers and boundary elements, in the large expanse of the mammalian genome. Promoters are subject to distinct chromatin patterns and regulation according to their CpG content. Namely, high CpG content promoters assume an active conformation by default and low CpG content promoters are inactive by default. Histone modifications may fine-tune the activities of promoters, gene bodies and enhancers, and the stability of repressive domains. Emerging evidence suggests that there are global correspondences between histone modification patterns, replication timing and higher-order nuclear structures. The amount of genome-scale data on covalent histone modification patterns is rapidly increasing. This Review brings together current knowledge on how modification 'signatures' relate to the structure and function of chromatin, from regulatory elements and gene structure to organization in the nucleus. A succession of technological advances over the past decade have enabled researchers to chart maps of histone modifications and related chromatin structures with increasing accuracy, comprehensiveness and throughput. The resulting data sets highlight the interplay between chromatin and genome function, dynamic variations in chromatin structure across cellular conditions, and emerging roles for large-scale domains and higher-ordered chromatin organization. Here we review a selection of recent studies that have probed histone modifications and successive layers of chromatin structure in mammalian genomes, the patterns that have been identified and future directions for research.

The Atacama Large Millimeter/submillimeter Array (ALMA) Survey of Star Formation and Evolution in Massive Protoclusters with Blue Profiles (ASSEMBLE) aims to investigate the process of mass assembly and its connection to high-mass star formation theories in protoclusters in a dynamic view. We observed 11 massive (M clump ≳ 103 M ⊙), luminous (L bol ≳ 104 L ⊙), and blue-profile (infall signature) clumps by ALMA with resolution of ∼2200–5500 au (median value of 3500 au) at 350 GHz (870 μm). We identified 248 dense cores, including 106 cores showing protostellar signatures and 142 prestellar core candidates. Compared to early stage infrared dark clouds (IRDCs) by ASHES, the core mass and surface density within the ASSEMBLE clumps exhibited a significant increment, suggesting concurrent core accretion during the evolution of the clumps. The maximum mass of prestellar cores was found to be 2 times larger than that in IRDCs, indicating that evolved protoclusters have the potential to harbor massive prestellar cores. The mass relation between clumps and their most massive core (MMCs) is observed in ASSEMBLE but not in IRDCs, which is suggested to be regulated by multiscale mass accretion. The mass correlation between the core clusters and their MMCs has a steeper slope compared to that observed in stellar clusters, which can be due to fragmentation of the MMC and stellar multiplicity. We observe a decrease in core separation and an increase in central concentration as protoclusters evolve. We confirm primordial mass segregation in the ASSEMBLE protoclusters, possibly resulting from gravitational concentration and/or gas accretion.