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Current LLM-based applications are becoming steadily available for everyone with a reliable access to technology and the internet. These applications offer benefits to their users that leave those without access to them at a serious disadvantage. Given the vastly large amount of data needed to train LLMs, the gap between languages with access to such quantity of data and those without it is currently larger than ever. Aimed at saving this gap, the Aina Project was created to provide Catalan with the necessary resources to keep being relevant in the context of AI/NLP applications based on LLMs. We thus present a set of strategies to consider when improving technology support for a mid- or low-resource language, specially addressing sustainability of high-quality data acquisition and the challenges involved in the process. We also introduce a large amount of new annotated data for Catalan. Our hope is that those interested in replicating this work for another language can learn from what worked for us, the challenges that we faced, and the sometimes disheartening truth of working with mid- and low-resource languages, This work has been promoted and financed by the Generalitat de Catalunya through the Aina project. This work is funded by the Ministerio para la Transformación Digital y de la Función Pública and Plan de Recuperación, Transformación y Resiliencia- Funded by EU– NextGenerationEU within the framework of the project ILENIA with reference 2022/TL22/00215337, 2022/TL22/00215336, 2022/TL22/00215335 and 2022/TL22/00215334., Peer Reviewed, Postprint (published version)

The Ice Sheet Model Intercomparison Project for CMIP6 (ISMIP6) is the primary effort of CMIP6 (Coupled Model Intercomparison Project–Phase 6) focusing on ice sheets, designed to provide an ensemble of process-based projections of the ice-sheet contribution to sea-level rise over the twenty-first century. However, the behavior of the Antarctic Ice Sheet beyond 2100 remains largely unknown: several instability mechanisms can develop on longer time scales, potentially destabilizing large parts of Antarctica. Projections of Antarctic Ice Sheet evolution until 2300 are presented here, using an ensemble of 16 ice-flow models and forcing from global climate models. Under high-emission scenarios, the Antarctic sea-level contribution is limited to less than 30 cm sea-level equivalent (SLE) by 2100, but increases rapidly thereafter to reach up to 4.4 m SLE by 2300. Simulations including ice-shelf collapse lead to an additional 1.1 m SLE on average by 2300, and can reach 6.9 m SLE. Widespread retreat is observed on that timescale in most West Antarctic basins, leading to a collapse of large sectors of West Antarctica by 2300 in 30%–40% of the ensemble. While the onset date of retreat varies among ice models, the rate of upstream propagation is highly consistent once retreat begins. Calculations of sea-level contribution including water density corrections lead to an additional ∼10% sea level and up to 50% for contributions accounting for bedrock uplift in response to ice loading. Overall, these results highlight large sea-level contributions from Antarctica and suggest that the choice of ice sheet model remains the leading source of uncertainty in multi-century projections.

The structural phase transitions of Pr(Sr0.1Ca0.9)2Mn2O7 have been studied by synchrotron radiation x-ray powder diffraction. Three different charge order (CO) phases are identified as a function of temperature. The three phases have a checkerboard arrangement of compressed and expanded MnO6 octahedra in the perovskite bilayers. The structural changes associated with each transition are described in terms of the mode decomposition analysis with respect to the parent tetragonal structure. The high-temperature phase exhibits an orthorhombic symmetry (Amam) due to cooperative tilts of the MnO6 octahedra that can be ascribed to the irreducible representation (irrep) X3−. On cooling, the CO1 phase with Pbnm symmetry arises from the condensation of modes belonging to the irrep DT2 together with breathing (X1+) and antiferrodistortive (M5− and Y2) modes. The Mn site is split into two nonequivalent Mn atoms (Mn1 and Mn2) with a small charge segregation, and the asymmetric environment of Mn1 atoms form zigzag chains along the doubled b axis. Further cooling leads to the formation of the CO2 phase that comes from a relative change between the directions of previous X3− and DT2 distortions, producing the simultaneous condensation of new DT1 and ferrodistortive GM5− modes. In the CO2 structure (Am2m symmetry), Mn2 atoms are split into two nonequivalent sites but with similar oxidation states. Then the checkerboard arrangement between Mn1 and Mn2 atoms is preserved but with a reorientation of the zigzag chains along the a axis. At lower temperatures, the CO3 phase arises from a new direction change of irrep X3−, leading to the simultaneous condensation of new secondary modes. Its symmetry is Pn21m, and the Mn1 site is now split, which leads to a total of four nonequivalent Mn sites in the unit cell. In this phase, more tilts of the MnO6 octahedra are allowed following the a−b−c+ tilt schema.

Graphene oxide has been prepared from an industrial coke-like waste. The morphology of this material (GO-CW) is similar to that of standard graphene oxide (GO-G), although its surface has more defects. Both materials were used to prepare hybrid NHC-Ir(I)/graphene materials, consisting of molecular Ir(NHC) complexes covalently anchored to the graphene surface through the NHC moiety, following two different synthetic routes: (a) direct graphene electrografting of the previously synthesized aniline-functionalized imidazole-2-ylidene-Ir(I) complex, and (b) a two-step sequence comprising initial electrografting of aniline-imidazolium salts and subsequent chemical reaction with Ir(I) precursor anchoring imidazole-2-ylidene-Ir(I) molecular complexes. The synthesized NHC-Ir/graphene hybrid catalysts are active in the oxygen evolution reaction (OER) resulting in current densities in a similar range to those of other NHC-iridium(I) catalysts supported on GO. The highest activity corresponds to hybrid catalysts prepared by the two-step route, with even higher activity and stability when graphene oxide from industrial waste is used. EXAFS spectra of the materials prepared from both synthesis routes before oxidation catalysis reveal the local Ir coordination shell and a structural interaction between Ir and graphene. Both XANES and EXAFS spectra after electrocatalysis point to more oxidized species in which the molecular nature of the iridium catalysts is preserved.

We report on the dielectric and electrocaloric properties of Ba1−yCayTi1−xHfxO3 for compositions 0.12

Rate-induced tipping (R-tipping) describes the fact that, for multistable dynamic systems, an abrupt transition can take place not only because of the forcing magnitude, but also because of the forcing rate. In the present work, we demonstrate through the case study of a piecewise-linear oscillator (PLO), that increasing the rate of forcing can make the system tip in some cases but might also prevent it from tipping in others. This counterintuitive effect is further called non-monotonous R-tipping (NMRT) and has already been observed in recent studies. We show that, in the present case, the reason for NMRT is the peak synchronisation of oscillatory responses operating on different time scales. We further illustrate that NMRT can be observed even in the presence of additive white noise of intermediate amplitude. Finally, NMRT is also observed on a van-der-Pol oscillator with an unstable limit cycle, suggesting that this effect is not limited to systems with a discontinuous right-hand side such as the PLO. This insight might be highly valuable, as the current research on tipping elements is shifting from an equilibrium to a dynamic perspective while using models of increasing complexity, in which NMRT might be observed but hard to understand.

In the last decades, great effort has been made to reconstruct the Laurentide Ice Sheet (LIS) during the Last Glacial Maximum (LGM; ca. 21000 years before present, 21kyr ago). Uncertainties underlying its modelling have led to notable differences in fundamental features such as its maximum elevation, extent and total volume. As a result, the uncertainty in ice dynamics and thus in ice extent, volume and ice stream stability remains large. We herein use a higher-order three-dimensional ice sheet model to simulate the LIS under LGM boundary conditions for a number of basal friction formulations of varying complexity. Their consequences for the Laurentide ice streams, configuration, extent and volume are explicitly quantified. Total volume and ice extent generally reach a constant equilibrium value that falls close to prior LIS reconstructions. Simulations exhibit high sensitivity to the dependency of the basal shear stress on the sliding velocity. In particular, a regularised Coulomb friction formulation appears to be the best choice in terms of ice volume and ice stream realism. Pronounced differences are found when the basal friction stress is thermomechanically coupled: the base remains colder, and the LIS volume is lower than in the purely mechanical friction scenario counterpart. Thermomechanical coupling is fundamental for producing rapid ice streaming, yet it leads to a similar ice distribution overall.

Most of the spiral magnetoelectric multiferroics investigated in recent years are geometrically or exchange-frustrated magnets, where the presence of triangular or other frustrated spin networks produce low magnetic transition temperatures. This critically limits their potential uses. The exceptional stability of the spiral magnetic order (at TS) in the layered structure of the YBaCuFeO5 double perovskite involves a nonconventional mechanism: spiral order by disorder. The model has been theoretically developed by Scaramucci et al. [Phys. Rev. Res. 2, 013273 (2020)10.1103/PhysRevResearch.2.013273] after the discovery of a huge impact of cation disorder on TS [M. Morin, Nat. Commun. 7, 13758 (2016)10.1038/ncomms13758]. In this work the influence of disorder (and only disorder) on the magnetic phase diagram is studied on a quantitative basis extending the range of previous studies. We thoroughly investigate the impact of frustration due to B-site disorder (nd) on the magnetic spirals in the reference composition YBaCuFeO5. The interplay between disorder, stability, and the detailed features of the incommensurate spiral magnetic orders were systematic, quantitative, and methodically investigated in samples of identical composition, spanning a wide range of nd values. Three different regimes are distinguished in the YBaCuFeO5 phase diagram versus disorder. A triple point is found in YBaCuFeO5 driven by Fe/Cu disorder that sets limits to TS and the cycloidal component of the helicoidal order. These layered materials appear as a very efficient realization of the avenue "spiral order by disorder"to supply functional helimagnets at normal working temperatures.

Magnetism in SmBaMn2O5 was investigated on a single crystal by magnetic and neutron diffraction measurements. This is an oxygen deficient perovskite with a layered ordering of Sm and Ba cations. Mn atoms are coordinated with five oxygens forming a square pyramid and they are ordered in a checkerboard pattern of expanded-compressed pyramids in the ab-plane. The neutron diffraction study revealed a ferrimagnetic ordering of Mn moments below TN=134 K. Macroscopic measurements reveal a very anisotropic behavior. Measurements with the external magnetic field parallel (M||c) and perpendicular (M⊥c) to the c-axis confirm that this is the easy axis above 10 K. Below this temperature, the Sm sublattice begins to polarize and the magnetization M||c decreases while M⊥c experiences a huge increase. This indicates that Sm moments begin to order around 10 K in the ab-plane with a minor component on the c-axis that opposes the overall magnetization from Mn sublattices.

We here report on the study of the crystallographic and magnetic properties of layered perovskites Ca3Mn2-xRuxO7 (x≤0.9). We observe a solid solution between Mn and Ru atoms in the whole series and all samples present the same orthorhombic structure independently of the Ru content. Different magnetic structures, depending on the Ru content in the sample, have been determined using neutron powder diffraction. For low Ru doping (x≤0.1), there is a dominant G-type antiferromagnetic ordering in the perovskite bilayers but, differently from undoped Ca3Mn2O7, the magnetic moments are located on the ab plane. For higher Ru concentration (x≥0.3), the predominant G-type ordering is preserved along the y axis while an A-type component is developed along the x axis and its intensity increases as Ru content does. This component is characterized by a ferromagnetic ordering in the a direction of one of the Mn(Ru)O6 layers, coupled antiferromagnetically with the neighbor Mn(Ru)O6 layer within the same bilayer. The study of the macroscopic magnetic properties shows that ferromagneticlike correlations are enhanced with increasing Ru content as deduced from the shift to higher temperature of the onset of the magnetic transition temperature. The magnetic transitions take place in two steps. At higher temperatures (140-200 K), short-range magnetic correlations are established. Tiny spontaneous magnetization is observed in the hysteresis loops with small coercive field. At TN≈115-125K, long-range antiferromagnetic ordering is developed. The ferromagnetic component remains with a strong increase of coercivity. We discuss in the paper the possible origins of this ferromagnetic contribution.

We report results from an in–plane and out–of–plane impedance study on SmB6 single crystals, performed at low temperatures and over a wide frequency range. A universal equivalent circuit describes the dielectric behavior of this system across the transition, from surface to bulk dominated electrical conduction between 2 and 10 K. We identify the resistive, capacitive, and inductive contributions to the impedance. The equivalent inductance, obtained from fits to experimental data, drops drastically with increasing temperature, as the bulk starts to control electrical conduction. Self–sustained voltage oscillations, observed below 6 K across small crystals when biased with a dc current, point to a large SmB6 self–capacitance, likely brought by the surface states.

As refrigeration is essential for health and comfort, food, medicine or electronics, it represents a large and growing fraction of the worldwide electricity consumption. The current cooling technology, based on the compression of harmful gases, has a limited energy efficiency and contributes significantly to global warming. Caloric effects are among the most promising climatefriendly alternatives because they lead to higher energy efficiencies and use solid refrigerants that can be prepared without toxic elements. Electrocaloric (EC) materials show reversible thermal changes when subjected to variations of an applied electric (E) field, known as the electrocaloric effect (ECE), which maximizes near a ferroelectric phase transition. While the research in their magnetocaloric (MC) counterparts is rather mature, EC materials have been in the spotlight only in the last ten years, being advantageous over MC because of the ease of application of E fields. Up to now, the research in EC materials has been dominated by lead-based oxides. Sufficiently large ECE values for cooling applications have only been observed in thin-film samples. We have investigated new EC oxides (bulk and thin film) by making use of in-house laboratory methods for the “direct” and “indirect” measurements of the ECE, combined with complementary synchrotron-based X-ray absorption spectroscopy. In particular, layer-structured ferroelectric Aurivillius oxides Srn-3Bi4TinO3n+3 (n = 4, 5), where the A- and B-site of the “n” perovskite-like layers are occupied by Sr/Bi and Ti, respectively. The Curie temperature TC of their ferroelectric transitions is about 800 K and 560 K for n = 4 and 5, respectively. Aiming at enhancing their EC response at near room temperature (RT), chemical substitutions at the A- (La3+) and B-site (Nb5+) have been applied to tune TC close to RT. For both series of compounds (n = 4, 5), we found that La-doping is effective in decreasing TC and in promoting a relaxor ferroelectric be