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Schiff bases are a crucial component in various functional materials but often exhibit non‐emissive behavior which significantly limits their potential applications as luminescent materials. However, traditional approaches to convert them into aggregate emitters often require intricate molecular design, tedious synthesis, and significant time and resource consumption. Herein, we present a cocrystallization‐induced emission strategy that can transform non‐emissive (hetero)aryl‐substituted Schiff bases into green‐yellow to yellow aggregate emitters via even simple grinding of a mixture of Schiff bases and 1,2,4,5‐tetracyanobenzene (TCB) mixtures. The combined experimental and theoretical analysis revealed that the cocrystallization inhibits the C=N isomerization and promotes face‐to‐face π–π interaction, which restricts access to both the dark state and canonical intersection to ultimately induce emission. Furthermore, the induced emission enables the observation of solid‐state molecular diffusion through fluorescence signals, advancing white light emission diodes, and notably, solution‐processed organic light‐emitting diodes based on cocrystal for the first time. This study not only highlights the potential of developing new C=N structural motifs for AIEgens but also could boost advancements in related structure motifs like C=C and N=N. [ABSTRACT FROM AUTHOR]

Online health platforms play an important role in chronic disease management. Patients participate in online health platforms to receive and provide health‐related support from each other. However, there remains a debate about whether the influence of social interaction on patient health anxiety is linearly positive. Based on uncertainty, information overload, and the theory of motivational information management, we develop and test a model considering a potential curvilinear relationship between social interaction and health anxiety, as well as a moderating effect of health literacy. We collect patient interaction data from an online health platform based on chronic disease management in China and use text mining and econometrics to test our hypotheses. Specifically, we find an inverted U‐shaped relationship between informational provision and health anxiety. Our results also show that information receipt and emotion provision have U‐shaped relationships with health anxiety. Interestingly, health literacy can effectively alleviate the U‐shaped relationship between information receipt and health anxiety. These findings not only provide new insights into the literature on online patient interactions but also provide decision support for patients and platform managers. [ABSTRACT FROM AUTHOR]

LED array microscopes have the advantages of miniaturisation and low cost. It has been demonstrated that LED array microscopes outperform Köhler illumination microscopes in some applications. A LED array allows for a large numerical aperture of illumination. The larger numerical aperture of illumination brings the higher spatial resolution, but the lower image contrast as well. Therefore, there is a tradeoff between resolution and contrast for LED array microscopes. The Fourier ptychographic algorithm can overcome this tradeoff by increasing image contrast without sacrificing spatial resolution. However, the Fourier ptychographic algorithm requires acquisition of multiple images, which is time‐consuming and results in live sample imaging challenging. To solve this problem, we develop contrast‐enhanced, single‐shot LED array microscopy based on the Fourier ptychographic algorithm and deep learning. The sample to be imaged is under illumination by all LEDs of the array simultaneously. The image captured is fed to several trained convolutional neural networks to generate the same number of images that are required by the Fourier ptychographic algorithm. We experimentally present that the image contrast of the final reconstruction is remarkably improved in comparison with the image captured. The proposed method can also produce chromatic‐aberration‐free results, even when an objective without aberration correction is used. We believe the method might provide live sample imaging with a low‐cost approach. [ABSTRACT FROM AUTHOR]

Background: The gene encoding the transcription factor, Grainyhead‐like 3 (Grhl3), plays critical roles in mammalian development and homeostasis. Grhl3‐null embryos exhibit thoraco‐lumbo‐sacral spina bifida and soft‐tissue syndactyly. Additional studies reveal that these embryos also exhibit an epidermal proliferation/differentiation imbalance. This manifests as skin barrier defects resulting in peri‐natal lethality and defective wound repair. Despite these extensive analyses of Grhl3 loss‐of‐function models, the consequences of gain‐of‐function of this gene have been difficult to achieve. Results: In this study, we generated a novel mouse model that expresses Grhl3 from a transgene integrated in the Rosa26 locus on an endogenous Grhl3‐null background. Expression of the transgene rescues both the neurulation and skin barrier defects of the knockout mice, allowing survival into adulthood. Despite this, the mice are not normal, exhibiting a range of phenotypes attributable to dysregulated Grhl3 expression. In mice homozygous for the transgene, we observe a severe Shaker‐Waltzer phenotype associated with hearing impairment. Micro‐CT scanning of the inner ear revealed profound structural alterations underlying these phenotypes. In addition, these mice exhibit other developmental anomalies including hair loss, digit defects, and epidermal dysmorphogenesis. Conclusion: Taken together, these findings indicate that diverse developmental processes display low tolerance to dysregulation of Grhl3. Key Findings: We established a novel mouse model of Grhl3 misexpression.Restoration of Grhl3 expression in Grhl3‐null mice fully rescues skin barrier and neural tube defects, allowing survival into adulthood.Misexpression of Grhl3 perturbs digit morphogenesis and epidermal homeostasis.Misexpression of Grhl3 leads to inner ear malformation and hearing impairment.This novel mouse model uncovered multiple previously unsuspected developmental events that are dependent on stringent regulation of Grhl3 expression. [ABSTRACT FROM AUTHOR]

Ultrawide‐bandgap semiconductors such as AlN, BN, and diamond hold tremendous promise for high‐efficiency deep‐ultraviolet optoelectronics and high‐power/frequency electronics, but their practical application has been limited by poor current conduction. Through a combined theoretical and experimental study, it is shown that a critical challenge can be addressed for AlN nanostructures by using N‐rich epitaxy. Under N‐rich conditions, the p‐type Al‐substitutional Mg‐dopant formation energy is significantly reduced by 2 eV, whereas the formation energy for N‐vacancy related compensating defects is increased by ≈3 eV, both of which are essential to achieve high hole concentrations of AlN. Detailed analysis of the current−voltage characteristics of AlN p‐i‐n diodes suggests that current conduction is dominated by hole‐carrier tunneling at room temperature, which is directly related to the activation energy of Mg dopants. At high Mg concentrations, the dispersion of Mg acceptor energy levels leads to drastically reduced activation energy for a portion of Mg dopants, evidenced by the small tunneling energy of 67 meV, which explains the efficient current conduction and the very small turn‐on voltage (≈5 V) for the diodes made of nanoscale AlN. This work shows that nanostructures can overcome the dopability challenges of ultrawide‐bandgap semiconductors and significantly increase the efficiency of devices. [ABSTRACT FROM AUTHOR]

There has been selective pressure to maintain a skin barrier since terrestrial animals evolved 360 million years ago. These animals acquired an unique integumentary system with a keratinized, stratified, squamous epithelium surface barrier. The barrier protects against dehydration and entry of microbes and toxins. The skin barrier centres on the stratum corneum layer of the epidermis and consists of cornified envelopes cemented by the intercorneocyte lipid matrix. Multiple components of the barrier undergo cross‐linking by transglutaminase (TGM) enzymes, while keratins provide additional mechanical strength. Cellular tight junctions also are crucial for barrier integrity. The grainyhead‐like (GRHL) transcription factors regulate the formation and maintenance of the integument in diverse species. GRHL3 is essential for formation of the skin barrier during embryonic development, whereas GRHL1 maintains the skin barrier postnatally. This is achieved by transactivation of Tgm1 and Tgm5, respectively. In addition to its barrier function, GRHL3 plays key roles in wound repair and as an epidermal tumour suppressor. In its former role, GRHL3 activates the planar cell polarity signalling pathway to mediate wound healing by providing directional migration cues. In squamous epithelium, GRHL3 regulates the balance between proliferation and differentiation, and its loss induces squamous cell carcinoma (SCC). In the skin, this is mediated through increased expression of MIR21, which reduces the expression levels of GRHL3 and its direct target, PTEN, leading to activation of the PI3K‐AKT signalling pathway. These data position the GRHL family as master regulators of epidermal homeostasis across a vast gulf of evolutionary history. [ABSTRACT FROM AUTHOR]