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We report on the nonlinear optical signatures of quantum phase transitions in the high-temperature superconductor YBCO, observed through high harmonic generation. While the linear optical response of the material is largely unchanged when cooling across the phase transitions, the nonlinear optical response sensitively imprints two critical points, one at the critical temperature of the cuprate with the exponential growth of the surface harmonic yield in the superconducting phase and another critical point, which marks the transition from strange metal to pseudogap phase. To reveal the underlying microscopic quantum dynamics, a strong-field quasi-Hubbard model was developed, which describes the measured optical response dependent on the formation of Cooper pairs. Further, the theory provides insight into the carrier scattering dynamics and allows us to differentiate between the superconducting, pseudogap, and strange metal phases.Thedirect connection between nonlinear optical response andmicroscopic dynamics provides a powerful methodology to study quantum phase transitions in correlated materials. Further implications are light wave control over intricate quantum phases, light—matter hybrids, and application for optical quantum computing.

Polycomb proteins play an essential role in maintaining the repression of developmental genes in self-renewing embryonic stem cells. The exact mechanism allowing the derepression of polycomb target genes during cell differentiation remains unclear. Our project aimed to identify Cbx8 binding sites in differentiating mouse embryonic stem cells. Therefore, we used a genome-wide chromatin immunoprecipitation of endogenous Cbx8 coupled to direct massive parallel sequencing (ChIP-Seq). Our analysis identified 171 high confidence peaks. By crossing our data with previously published microarray analysis, we show that several differentiation genes transiently recruit Cbx8 during their early activation. Depletion of Cbx8 partially impairs the transcriptional activation of these genes. Both interaction analysis, as well as chromatin immunoprecipitation experiments support the idea that activating Cbx8 acts in the context of an intact PRC1 complex. Prolonged gene activation results in eviction of PRC1 despite persisting H3K27me3 and H2A ubiquitination. The composition of PRC1 is highly modular and changes when embryonic stem cells commit to differentiation. We further demonstrate that the exchange of Cbx7 for Cbx8 is required for the effective activation of differentiation genes. Taken together, our results establish a function for a Cbx8-containing complex in facilitating the transition from a Polycomb-repressed chromatin state to an active state. As this affects several key regulatory differentiation genes this mechanism is likely to contribute to the robust execution of differentiation programs.

Rapid progress in information technologies has spurred the need for innovative memory concepts, for which advanced data-processing methods and tailor-made materials are required. Here we introduce a previously unexplored nanoscale magnetic object: an analog magnetic vortex controlled by electric-field-induced ion motion, termed magneto-ionic vortex or “vortion”. This state arises from paramagnetic FeCoN through voltage gating and gradual N 3– ion extraction within patterned nanodots. Unlike traditional vortex states, vortions offer comprehensive analog adjustment of key properties such as magnetization amplitude, nucleation/annihilation fields, or coercivity using voltage as an energy-efficient tuning knob. This manipulation occurs post-synthesis, obviating the need for energy-demanding methods like laser pulses or spin-torque currents. By leveraging an overlooked aspect of N 3– magneto-ionics—planar ion migration within nanodots—precise control of the magnetic layer’s thickness is achieved, which enables reversible transitions among paramagnetic, single-domain, and vortion states, offering future prospects for analog computing, multi-state data storage, or brain-inspired devices. Magneto-ionics are a promising approach for controlling magnetism via electric fields, but most studies have been limited to thin films, rather than the nanostructures that would form the basis of a magneto-ionic memory unit. Here, Spasojevic et al demonstrate magneto-ionic control over transitions among paramagnetic, single domain, and vortex states in an array of nanodots.

The exploration of metal–insulator transitions to produce field-induced reversible resistive switching effects has been a longstanding pursuit in materials science. Although the resistive switching effect in strongly correlated oxides is often associated with the creation or annihilation of oxygen vacancies, the underlying mechanisms behind this phenomenon are complex and, in many cases, still not clear. This study focuses on the analysis of the superconducting performance of cuprate YBa 2 Cu 3 O 7−δ (YBCO) devices switched to different resistive states through gate voltage pulses. The goal is to evaluate the effect of field-induced oxygen diffusion on the magnetic field and angular dependence of the critical current density and identify the role of induced defects in the switching performance. Transition electron microscopy measurements indicate that field-induced transition to high resistance states occurs through the generation of YBa 2 Cu 4 O 7 (Y124) intergrowths with a large amount of oxygen vacancies, in agreement with the obtained critical current density dependences. These results have significant implications for better understanding the mechanisms of field-induced oxygen doping in cuprate superconductors and their role on the superconducting performance.

Abstract This paper introduces the Comparative Agendas Project system of coding as well as a wealth of gathered and in process data from Latin America using this established and reliable system for capturing policy attention comparatively and over time. While this is not the first introduction of the coding system, it is the first introduction aimed at Latin America and a new type of political system beyond North American and European democracies. First, we present an overview of the Comparative Agendas Project (CAP) and the Master Codebook used to create comparative policy attention data across countries, over time, and between agendas. These details of CAP are discussed for Latin America in general and for Brazil, Colombia and Ecuador, countries that recently started to gather data using these coding. Resumen: Este artículo presenta el sistema de codificación del Comparative Agendas Project, que es capaz de capturar la atención política de manera comparada y a lo largo del tiempo. Presenta también una amplia gama de datos recogidos y procesados en América Latina, sobre la base de este consolidado y fiable sistema de codificación. Aunque no sea un sistema inédito, esta es la primera vez que se introduce en América Latina y en un tipo de sistema político diferente del que se observa en las democracias de América do Norte y Europa. Para ello, ofrecemos una descripción del Comparative Agendas Project y de su libro de códigos (Master Codebook), usado para obtener datos de atención política de forma comparada entre países y distintos tipos de agendas a lo largo del tiempo. Esos detalles se discuten en relación con América Latina en general y con el contexto nacional de Brasil, Colombia y Ecuador, países de la región que cuentan con el primer conjunto de datos recogidos con ese sistema de codificación. Resumo Esse artigo apresenta o sistema de codificação do Comparative Agendas Project, que é capaz de capturar a atenção política de maneira comparada e ao longo do tempo. Apresenta também uma ampla gama de dados coletados e em processamento na América Latina, já usando esse consolidado e confiável sistema de codificação. Embora não seja um sistema inédito, essa é a primeira vez que está sendo introduzido na América Latina e em um tipo de sistema político diferente do que se observa nas democracias da América do Norte e da Europa. Para isso, oferecemos um panorama do Comparative Agendas Project e de seu livro de códigos (Master Codebook), usado para obter dados de atenção política de forma comparada entre os países e suas agendas, ao longo do tempo. Esses detalhes são discutidos em relação a América Latina em geral e ao contexto nacional do Brasil, Colômbia e Equador, países da região que contam com a primeira leva de dados processados com esse sistema de codificação.

Cancer cells possess aberrant proteomes that can arise by the disruption of genes involved in physiological protein degradation. Here we demonstrate the presence of promoter CpG island hypermethylation-linked inactivation of DERL3 (Derlin-3), a key gene in the endoplasmic reticulum-associated protein degradation pathway, in human tumours. The restoration of in vitro and in vivo DERL3 activity highlights the tumour suppressor features of the gene. Using the stable isotopic labelling of amino acids in cell culture workflow for differential proteome analysis, we identify SLC2A1 (glucose transporter 1, GLUT1) as a downstream target of DERL3. Most importantly, SLC2A1 overexpression mediated by DERL3 epigenetic loss contributes to the Warburg effect in the studied cells and pinpoints a subset of human tumours with greater vulnerability to drugs targeting glycolysis. Defective proteins or functional proteins that are no longer needed can be degraded in the endoplasmic reticulum. In this study, Lopez-Serra et al. show that DERL3, which is involved in protein degradation in the endoplasmic reticulum, is aberrantly silenced in cancer, leading to activation of a glucose transporter and dysregulated glycolysis.

The synthesis of a terbium-based 2D metal–organic framework (MOF), of formula [Tb(MeCOO)(PhCOO)2] (1), a crystalline material formed by neutral nanosheets held together by Van der Waals interactions, is presented. The material can be easily exfoliated by sonication and deposited onto different substrates. Uniform distributions of Tb-2D MOF flakes onto silicon were obtained by spin-coating. We report the luminescent and magnetic properties of the deposited flakes compared with those of the bulk. Complex 1 is luminescent in the visible and has a sizeable quantum yield of QY = 61% upon excitation at 280 nm. Photoluminescence measurements performed using a micro-Raman set up allowed us to characterize the luminescent spectra of individual flakes on silicon. Magnetization measurements of flakes-on-silicon with the applied magnetic field in-plane and out-of-plane display anisotropy. Ac susceptibility measurements show that 1 in bulk exhibits field-induced slow relaxation of the magnetization through two relaxation paths and the slowest one, with a relaxation time of τlf ≈ 0.5 s, is assigned to a direct process mechanism. The reported exfoliation of lanthanide 2D-MOFs onto substrates is an attractive approach for the development of multifunctional materials and devices for different applications.

Mountains have socio-economic and environmental importance for the entire world, and they are also one of the regions most threatened by global change. As mountains are systems in which the human and nature dimensions are tightly interconnected, studying them as social–ecological systems (SES) is increasingly common. To date, a variety of approaches and frameworks have been used to study mountain SES, making comparisons across mountain areas challenging. In this paper, we use Ostrom’s SES framework to review the mountain SES peer-reviewed literature under a common scope, aiming at unraveling which frameworks, approaches, domains, sectors, and elements are studied by researchers. Among the 169 reviewed manuscripts, only 28% of them employed a framework to study their system, and custom-made frameworks were preferred over existing ones. Although most research articles were in the domain of environmental sciences, socio-economic attributes were included more often than ecological ones, and more than 30% did not combine social and ecological information. Moreover, albeit most manuscripts had an empirical approach, field data were seldomly used. Future works should focus on collecting social and ecological data at comparable scales, as well as on developing tools to effectively integrate both dimensions in mountain SES studies. Finally, we examine components of mountain socio-ecological systems commonly addressed in literature, highlighting important elements for overall and sector-specific sustainability. Regarding social aspects, understanding local inhabitants’ diverse perspectives and socioeconomic context is crucial. In terms of ecological elements, describing climatic patterns and ecosystem history is key.

The magnetic flux pinning capabilities of YBa 2 Cu 3 O 7-x (YBCO) coated conductors vary strongly across different regions of the magnetic field–temperature phase diagram and with the orientation of the magnetic field θ . Here, we determine the optimal pinning landscape for a given region of the phase diagram by investigating the critical current density J c ( H , θ , T ) in the 5–77 K temperature range, from self-field to high magnetic fields of 35 T. Our systematic analysis reveals promising routes for artificially engineering YBCO coated conductors in any region of interest of the phase diagram. In solution-derived nanocomposites, we identify the relevance of coexisting high amounts of short stacking faults, Cu-O vacancy clusters, and segmentation of twin boundaries, in combination with nanoparticles, for enhanced pinning performance at high magnetic fields and low temperatures. Moreover, we demonstrate that twin boundaries preserve a high pinning energy in thick YBCO films, which is beneficial for the pinning performance at high magnetic fields and high temperatures. Optimizing the microstructure of YBa 2 Cu 3 O 7-x coated conductors across the magnetic field–temperature phase diagram is important for strengthening vortex pinning and thereby enhancing the critical current. Here, a systematic microstructural investigation identifies the most relevant vortex pinning contributions in a broad range of temperatures and magnetic fields.

In recent years Resistive Random Access Memory (RRAM) is emerging as the most promising candidate to substitute the present Flash Technology in the non-volatile memory market. RRAM are based on the Resistive Switching (RS) effect, where a change in the resistance of the material can be reversibly induced upon the application of an electric field. In this sense, strongly correlated complex oxides present unique intrinsic properties and extreme sensitivity to external perturbations, which make them suitable for the nanoelectronics of the future. In particular, metallic complex oxides displaying metal-insulator transition (MIT) are very attractive materials for applications and are barely explored as RS active elements. In this work, we analyze the RS behavior of different films belonging to three different families of metallic perovskites: La 0.8 Sr 0.2 MnO 3 , YBa 2 Cu 3 O 7-δ and NdNiO 3 . We demonstrate that these mixed electronic-ionic conductors undergo a metal-insulator transition upon the application of an electric field, being able to transform the bulk volume. This volume RS is different in nature from interfacial or filamentary type and opens new possibilities of robust device design. As an example, we present a proof-of-principle result from a 3-Terminal configuration with multilevel memory states.