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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]

The early steps of embryogenesis are controlled exclusively by the quality of oocyte that linked closely to its mechanical properties. The mechanical properties of an oocyte were commonly characterized by assuming it was homogeneous such that the result deviated significantly from the true fact that it was composed of subcellular components. In this work, we accessed and characterized the subcellular components of the oocytes and developed a layered high-fidelity finite element model for describing the viscoelastic responses of an oocyte under loading. The zona pellucida (ZP) and cytoplasm were isolated from an oocyte using an in-house robotic micromanipulation platform and placed on AFM to separately characterizing their mechanical profiling by analyzing the creep behavior with the force clamping technique. The spring and damping parameters of a Kelvin–Voigt model were derived by fitting the creeping curve to the model, which were used to define the shear relaxation modulus and relaxation time of ZP or cytoplasm in the ZP and cytoplasm model. In the micropipette aspiration experiment, the model was accurate sufficiently to deliver the time-varying aspiration depth of the oocytes under the step negative pressure of a micropipette. In the micropipette microinjection experiment, the model accurately described the intracellular strain introduced by the penetration. The developed oocyte FEM model has implications for further investigating the viscoelastic responses of the oocytes under different loading settings.

Summary: Self‐incompatibility plays a vital role in angiosperms, by preventing inbreeding depression and maintaining genetic diversity within populations. Following polyploidization, many angiosperm species transition from self‐incompatibility to self‐compatibility.Here, we investigated the S‐locus in Brassicaceae and identified distinct origins for the sRNA loci, SMI and SMI2 (SCR Methylation Inducer 1 and 2), within the S‐locus. The SMI loci were found to be widespread in Cruciferae, whereas the SMI2 loci were exclusive to Brassica species.Additionally, we discovered four major S‐haplotypes (BnS‐1, BnS‐6, BnS‐7, and BnS‐1300) in rapeseed. Overexpression of BnSMI‐1 in self‐incompatible Brassica napus ('S‐70S1300S6') resulted in a significant increase in DNA methylation in the promoter regions of BnSCR‐6 and BnSCR‐1300, leading to self‐compatibility. Conversely, by overexpressing a point mutation of BnSmi‐1 in the 'S‐70S1300S6' line, we observed lower levels of DNA methylation in BnSCR‐6 and BnSCR‐1300 promoters. Furthermore, the overexpression of BnSMI2‐1300 in the 'SI‐326S7S6' line inhibited the expression of BnSCR‐7 through transcriptional repression of the Smi2 sRNA from the BnS‐1300 haplotype.Our study demonstrates that the self‐compatibility of rapeseed is determined by S‐locus sRNA‐mediated silencing of SCR after polyploidization, which helps to further breed self‐incompatible or self‐compatible rapeseed lines, thereby facilitating the utilization of heterosis. [ABSTRACT FROM AUTHOR]

Brassica napus L. is an important oil crop. Salt stress is one of the major environmental conditions affecting the growth and development of B. napus, which may lead to yield reduction, quality deterioration, and even the death of B. napus. In this study, the B. napus semi-winter cultivar ZS11 was used as the experimental material to perform transcriptome sequencing on the leaf and root tissues with salt stress treatment (0, 0.25, 0.5, 1, 3, 6, 12, and 24 h). The measured 90 RNA-seq data provided the high-resolution time dynamic transcriptional expression spectrum of rapeseed tissues responding to salt stress was obtained. Correlation analysis showed that the samples exhibited significant clustering differences in early response and late response before and after 1 h salt stress treatment. Using DESeq2 for differential gene analysis, we identified 20,462 and 29,334 differential genes for the response of root and leaf tissues, respectively, indicating that the overall response of leaf tissue in rapeseed was more severe than the root. Furthermore, WGCNA was used to construct gene co-expression networks for the salt stress response in root and leaf tissues, respectively, and tan and yellow modules were significantly related to the early response to salt stress, and green and red modules were significantly related to the late response to salt stress. GO enrichment analysis was then performed, and 41 and 26 core transcription factors responding to salt stress at the early and late stages, respectively, were selected from these networks. Functional annotation showed that the known Arabidopsis homologous genes involved in salt stress responses at different stages existed in all four modules, and core genes, such as BnWRKY46 and BnWRKY57, had abundant SNPs variation and haplotypes in 505 salt stress-treated rape population variation data, suggesting that these core transcription factors might be key candidate genes for rape salt stress response. This study provides a reliable data reference and candidate gene resources for improving salt tolerance in B. napus. [ABSTRACT FROM AUTHOR]