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Competition between ground states at phase boundaries can lead to significant changes in properties under stimuli, particularly when these ground states have different crystal symmetries. A key challenge is to stabilize and control the coexistence of symmetry-distinct phases. Using BiFeO3 layers confined between layers of dielectric TbScO3 as a model system, we stabilize the mixed-phase coexistence of centrosymmetric and non-centrosymmetric BiFeO3 phases at room temperature with antipolar, insulating and polar semiconducting behaviour, respectively. Application of orthogonal in-plane electric (polar) fields results in reversible non-volatile interconversion between the two phases, hence removing and introducing centrosymmetry. Counterintuitively, we find that an electric field 'erases' polarization, resulting from the anisotropy in octahedral tilts introduced by the interweaving TbScO3 layers. Consequently, this interconversion between centrosymmetric and non-centrosymmetric phases generates changes in the non-linear optical response of over three orders of magnitude, resistivity of over five orders of magnitude and control of microscopic polar order. Our work establishes a platform for cross-functional devices that take advantage of changes in optical, electrical and ferroic responses, and demonstrates octahedral tilts as an important order parameter in materials interface design.

Clinical, biomedical, and translational science has reached an inflection point in the breadth and diversity of available data and the potential impact of such data to improve human health and well-being. However, the data are often siloed, disorganized, and not broadly accessible due to discipline-specific differences in terminology and representation. To address these challenges, the Biomedical Data Translator Consortium has developed and tested a pilot knowledge graph-based "Translator" system capable of integrating existing biomedical data sets and "translating" those data into insights intended to augment human reasoning and accelerate translational science. Having demonstrated feasibility of the Translator system, the Translator program has since moved into development, and the Translator Consortium has made significant progress in the research, design, and implementation of an operational system. Herein, we describe the current system's architecture, performance, and quality of results. We apply Translator to several real-world use cases developed in collaboration with subject-matter experts. Finally, we discuss the scientific and technical features of Translator and compare those features to other state-of-the-art, biomedical graph-based question-answering systems.

Within clinical, biomedical, and translational science, an increasing number of projects are adopting graphs for knowledge representation. Graph-based data models elucidate the interconnectedness among core biomedical concepts, enable data structures to be easily updated, and support intuitive queries, visualizations, and inference algorithms. However, knowledge discovery across these "knowledge graphs" (KGs) has remained difficult. Data set heterogeneity and complexity; the proliferation of ad hoc data formats; poor compliance with guidelines on findability, accessibility, interoperability, and reusability; and, in particular, the lack of a universally accepted, open-access model for standardization across biomedical KGs has left the task of reconciling data sources to downstream consumers. Biolink Model is an open-source data model that can be used to formalize the relationships between data structures in translational science. It incorporates object-oriented classification and graph-oriented features. The core of the model is a set of hierarchical, interconnected classes (or categories) and relationships between them (or predicates) representing biomedical entities such as gene, disease, chemical, anatomic structure, and phenotype. The model provides class and edge attributes and associations that guide how entities should relate to one another. Here, we highlight the need for a standardized data model for KGs, describe Biolink Model, and compare it with other models. We demonstrate the utility of Biolink Model in various initiatives, including the Biomedical Data Translator Consortium and the Monarch Initiative, and show how it has supported easier integration and interoperability of biomedical KGs, bringing together knowledge from multiple sources and helping to realize the goals of translational science.

Order–disorder transitions are widely explored in various vortex structures in condensed matter physics, that is, in the type-II superconductors and Bose–Einstein condensates. In this study, the ordering of the polar vortex phase in [Pb(Zr0.4Ti0.6)O3]n/(SrTiO3)n (PZT/STO) superlattices is investigated through phase-field simulations. With a large tensile substrate strain, an antiorder vortex state (where the rotation direction of the vortex arrays in the neighboring ferroelectric layers are flipped) is discovered for short-period PZT/STO superlattice. The driving force is the induced in-plane polarization in the STO layers due to the large tensile epitaxial strain. Increasing the periodicity leads to antiorder to disorder transition, resulting from the high energy of the head-to-head/tail-to-tail domain structure in the STO layer. On the other hand, when the periodicity is kept constant in short-period superlattices, the order–disorder–antiorder transition can be engineered by mediating the substrate strain, due to the competition between the induction of out-of-plane (due to interfacial depolarization effect) and in-plane (due to strain) polarization in the STO layer. The 3D ordering of such polar vortices is still a topic of significant current interest and it is envisioned that this study will spur further interest toward the understanding of order–disorder transitions in ferroelectric topological structures.

Understanding the phase transitions and domain evolutions of mesoscale topological structures in ferroic materials is critical to realizing their potential applications in next-generation high-performance storage devices. Here, the behaviors of a mesoscale supercrystal are studied with 3D nanoscale periodicity and rotational topology phases in a PbTiO3 /SrTiO3 (PTO/STO) superlattice under thermal and electrical stimuli using a combination of phase-field simulations and X-ray diffraction experiments. A phase diagram of temperature versus polar state is constructed, showing the formation of the supercrystal from a mixed vortex and a-twin state and a temperature-dependent erasing process of a supercrystal returning to a classical a-twin structure. Under an in-plane electric field bias at room temperature, the vortex topology of the supercrystal irreversibly transforms to a new type of stripe-like supercrystal. Under an out-of-plane electric field, the vortices inside the supercrystal undergo a topological phase transition to polar skyrmions. These results demonstrate the potential for the on-demand manipulation of polar topology and transformations in supercrystals using electric fields. The findings provide a theoretical understanding that may be utilized to guide the design and control of mesoscale polar structures and to explore novel polar structures in other systems and their topological nature.

Aluminum (Al) exposure significantly interferes with the energy supply in astrocytes, which may be a potential mechanism of Al-induced neurotoxicity. This study was designed to explore the mechanisms of Al-induced energy supply impairment in rat C6 astroglioma cell line. Aluminum-maltolate (Al(mal)3) (0.1 mM, 24 h) exposure significantly decreased brain-type creatine kinase (BCK) co-localization with the endoplasmic reticulum (ER) and resulted in mitochondrial dysfunctions, accompanied by a decrease in AMPK phosphorylation. The results of molecular docking showed that Al(mal)3 increased BCK’s hydrophobicity and hindered the localization movement of BCK between subcells·H2O2 co-administration was found to exacerbate mitochondrial dysfunction, Ca2+ dyshomeostasis, and apoptosis. After treated with Al(mal)3, additional oxidative stress contributed to BCK activity inhibition but did not promote a further decrease in AMPK phosphorylation. The activation of p-AMPK by its agonist can partially restore mitochondrial function, BCK activity, and ER-localized-BCK levels in Al(mal)3-treated astrocytes. In summary, Al exposure resulted in a sustained depletion of the mitochondrial and antioxidant systems, which was associated with reduced p-AMPK activity and decreased ER-localized-BCK levels in astrocytes. This study provides a theoretical basis for exploring the mechanisms of neurotoxicity induced by Al exposure.

Antiferroelectric materials have seen a resurgence of interest because of proposed applications in a number of energy-efficient technologies. Unfortunately, relatively few families of antiferroelectric materials have been identified, precluding many proposed applications. Here, we propose a design strategy for the construction of antiferroelectric materials using interfacial electrostatic engineering. We begin with a ferroelectric material with one of the highest known bulk polarizations, BiFeO3. By confining thin layers of BiFeO3 in a dielectric matrix, we show that a metastable antiferroelectric structure can be induced. Application of an electric field reversibly switches between this new phase and a ferroelectric state. The use of electrostatic confinement provides an untapped pathway for the design of engineered antiferroelectric materials with large and potentially coupled responses.

Cell models play a crucial role in analyzing the mechanical response of cells and quantifying cellular damage incurred during micromanipulation. While traditional models can capture the overall mechanical behavior of cells, they often lack the ability to discern among distinct cellular components. Consequently, by employing dissipative particle dynamics, this study constructed a triangular network-like representation of the cell membrane along with cross-linked cytoskeletal chains. The mechanical properties of both the membrane and cytoskeleton were then analyzed through a series of simulated mechanical tests, validated against real-world experiments. The investigation utilized particle-tracking rheology to monitor changes in the mean square displacements of membrane particles over time, facilitating the analysis of the membrane’s storage and loss moduli. Additionally, the cytoskeletal network’s storage and loss moduli were examined via a double-plate oscillatory shear experiment. The simulation results revealed that both the membrane and cytoskeleton exhibit viscoelastic behavior, as evidenced by the power-law dependency of their storage and loss moduli on frequency. Furthermore, indentation and microinjection simulations were conducted to examine the overall mechanical properties of cells. In the indentation experiments, an increase in the shear modulus of the membrane’s WLCs correlated with a higher Young’s modulus for the entire cell. Regarding the microinjection experiment, augmenting the microinjection speed resulted in reduced deformation of the cell at the point of membrane rupture and a lower percentage of high strain.

Oncidium, an important tropical orchid, has high ornamental value due to its specific color and occupies a significant market position for the worldwide flower. Transcriptome analysis of flower and leaf color formation provides new sources for producing novel Oncidium hybridum cultivars. We sequenced 12 samples of flowers (yellow and white) and leaves (striped and regular) of O. hybridum and assembled 381,136 and 453,566 unigene sequences from RNA-seq data, respectively. Among unigenes, 662 and 1,324 differentially expressed genes were identified in flower and leaf samples, respectively. Gene ontology and pathway enrichment showed that secondary metabolite biosynthetic pathways were responsible for flower and leaf color formation. It was determined that UGT75C1, E2.4.1.115, CCD7, E2.1.1.76, and CCoAOMT are involved in regulating flower color, and UGT75C1, LHCB, UGT, RP-L18Ae, and ABCB1 play crucial roles in regulating leaf color. Kyoto Encyclopedia of Genes and Genomes analysis revealed that UGT75C1 was significantly enriched in the anthocyanin biosynthetic pathway, showing effects on flower and leaf colors. This study was the first detailed analysis of the molecular mechanisms of O. hybridum flower and leaf colors, and the results advanced the understanding of the genetic basis of flower and leaf colors; they also provided additional support for improving commercial value and producing novel cultivars of O. hybridum.

Host immune responses play central roles in controlling SARS-CoV2 infection, yet remain incompletely characterized and understood. Here, we present a comprehensive immune response map spanning 454 proteins and 847 metabolites in plasma integrated with single-cell multi-omic assays of PBMCs in which whole transcriptome, 192 surface proteins, and T and B cell receptor sequence were co-analyzed within the context of clinical measures from 50 COVID19 patient samples. Our study reveals novel cellular subpopulations, such as proliferative exhausted CD8 + and CD4 + T cells, and cytotoxic CD4 + T cells, that may be features of severe COVID-19 infection. We condensed over 1 million immune features into a single immune response axis that independently aligns with many clinical features and is also strongly associated with disease severity. Our study represents an important resource towards understanding the heterogeneous immune responses of COVID-19 patients and may provide key information for informing therapeutic development.

The manipulation of charge and lattice degrees of freedom in atomically precise, low-dimensional ferroelectric superlattices can lead to exotic polar structures, such as a vortex state. The role of interfaces in the evolution of the vortex state in these superlattices (and the associated electrostatic and elastic boundary conditions they produce) has remained unclear. Here, the toroidal state, arranged in arrays of alternating clockwise/counterclockwise polar vortices, in a confined SrTiO3 /PbTiO3 /SrTiO3 trilayer is investigated. By utilizing a combination of transmission electron microscopy, synchrotron-based X-ray diffraction, and phase-field modeling, the phase transition as a function of layer thickness (number of unit cells) demonstrates how the vortex state emerges from the ferroelectric state by varying the thickness of the confined PbTiO3 layer. Intriguingly, the vortex state arises at head-to-head domain boundaries in ferroelectric a1 /a2 twin structures. In turn, by varying the total number of PbTiO3 layers (moving from trilayer to superlattices), it is possible to manipulate the long-range interactions among multiple confined PbTiO3 layers to stabilize the vortex state. This work provides a new understanding of how the different energies work together to produce this exciting new state of matter and can contribute to the design of novel states and potential memory applications.

Objective To explore the relationship of aniseikonia with differences of diopter and axial length in myopia patients, and the possible factors causing aniseikonia. Methods A total of 322 myopia patients (4~40 years old) were selected from May to August, 2021, who underwent optometry in the Ophthalmology Outpatient Department of the Affiliated Hospital of North Sichuan Medical College. ARK-510A autorefractor and Dk-700 optometry system were used for optometry. IOL-Master 700 was used for the measurement of axial length. Aniseikonia were evaluated by binocular aniseikonia test. Gender, age, diopter (sphericity, cylindricity and spherical equivalent), axial length and range of aniseikonia were recorded. Spearman test, chi-square test and multiple linear regression were used to analyze the aniseikonia with the differences of diopter and axial length. At the same time, receiver operating characteristic (ROC) curve of the differences of diopter and axial length was drawn for aniseikonia. Results A total of 322 patients (159 males and 163 females) were included, at an age of (17.77±7.69) years, and the overall prevalence rate of aniseikonia was 15.22% (49 cases). In univariate analysis, the absolute values of all parameter were included in the analysis, the differences of sphericity (r=0.449, P < 0.001), cylindricity (r=0.596, P < 0.001), spherical equivalent (r=0.479, P < 0.001) and axial length (r=0.417, P < 0.001) were all positively correlated with range of aniseikonia. Multivariate analysis indicated that the difference between cylindricity and spherical equivalent showed greater effect on the range of aniseikonia, and the regression equation was Y=0.009-0.626X1 (cylindrical difference)-0.22 X2 (spherical equivalent difference)(F=159.17, P < 0.001, adjusted R2=0.496). In the analysis of risk factors, when the difference of sphericity was more than -2.00 D, and that of cylindricity and spherical equivalent was more than -1.00 D, the risk of aniseikonia was increased. In the diagnostic analysis, the difference of cylindricity (AUC=0.778; 95%CI: 0.69~0.87; P < 0.001; sensitivity: 53.06%, specificity: 99.63%) had the highest value in the diagnosis of aniseikonia. Conclusion Anisometropia does not necessarily lead to aniseikonia. The difference between cylindricity and spherical equivalent is the key factor for aniseikonia, and great attention should be paid in clinical diagnosis and treatment.

Objective To investigate the change rules of lens by analyzing the relationship between lens morphology and axial length in adolescents. Methods A total of 285 adolescents (6~18 years old, 570 eyes) who visited our ophthalmological department from May to June 2020 were enrolled in this study. Diopter, axial length, keratometry and lens parameters were obtained by optometry after cycloplegia, optical biomimetry (IOL Master) and anterior segment optical coherence tomography (CASIA2), respectively. The subjects were divided into 3 age groups (6~10, 11~14 and 15~8 years), and were also assigned into 3 groups in accordance with their equivalent spherical specularity: hyperopia, emmetropia and myopia groups. One-way analysis of variance was adopted to compare lens parameters among different age and refractive groups, and their relationships with axial length were analyzed with Pearson correlation analysis and linear regression analysis. Results In different age groups, statistical differences were observed in the radius of anterior surface curvature and the diopter of lens (P < 0.05); And similar results were seen in above 2 parameters and in the thickness and diameter of lens among different refractive groups (P < 0.05). The curvature radius of the anterior and posterior surface, diopter, and thickness and diameter of lens were all significantly correlated with the axial length of eye in different age groups and refractive groups (P < 0.001). In the hyperopia, emmetropia and myopia groups, with the increase of every 1 mm in ocular axis, the radius of anterior surface curvature was increased by 1.19, 1.04 and 0.58 mm; the radius of posterior surface curvature was increased by 0.41, 0.38 and 0.30 mm, the diopter was decreased by 1.68 D, 1.44 D and 0.98 D; the thickness was reduced by 0.076, 0.091 and 0.059 mm, and the diameter increased by 0.3, 0.23 and 0.24 mm, respectively. Conclusion The disparity of lens parameters among different ages and refractive states in adolescents is mainly caused by the diversity of axial length. The morphological changes of the lens are coordinated with the growth of axial length, but the changes will be decreased with the growth

We demonstrate a fiber-guided atom interferometer in a far-off-resonant trap (FORT) of 100 μK. The differential light shift (DLS) introduced by the FORT leads to the inhomogeneous dephasing of the tightly trapped atoms inside a hollow-core fiber. The DLS-induced dephasing is greatly suppressed in π / 2 - π - π / 2 Doppler-insensitive interferometry. The spin coherence time is extended to 13.4 ms by optimizing the coupling of the trapping laser beam into a quasi-single-mode hollow-core anti-resonant fiber. The Doppler-sensitive interferometry shows a much shorter coherence time, indicating that the main limits to our fiber-guided atom interferometer are the wide axial velocity distribution and the irregular modes of the Raman laser beams inside the fiber. This work paves the way for portable and miniaturized quantum devices, which have advantages for inertial sensing at arbitrary orientations and in dynamic environments. [ABSTRACT FROM AUTHOR]