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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]

Functional thin film superlattices with stability in extreme environments can lead to transformative performance in optical and thermal applications such as thermophotovoltaics. In this work, key issues associated with defects that prevent layer-by-layer growth in epitaxial, low-miscibility oxide superlattices are investigated. Layer protrusions, approximately 8 nm wide and 3 nm thick, arise from a strain relaxation mechanism in 8 nm bilayer superlattices of Ba(Zr0.5Hf0.5)O3/MgO and propagate through the subsequent superlattice layers forming an inverted pyramid structure that is spatially phase offset from the matrix. The density and size of these defects scales with the number of interfaces in the sample, indicating that surface roughness during growth is a significant factor in the formation of these defects. In situ high temperature transmission electron microscopy (1000 °C, in vacuo) measurement reveals that phase decomposition of Ba(Zr0.5Hf0.5)O3 and decoherence of the superlattice is nucleated by these defects. This work highlights that achieving optimum growth conditions is imperative to the synthesis of single-crystalline superlattices with sharp interfaces for optimized performance in extreme environments. [ABSTRACT FROM AUTHOR]

Background: Mammalian enabled (MENA) protein is a member of the enabled/vasodilator stimulated phosphoprotein (Ena/VASP) protein family, which regulates cytoplasmic actin network assembly. It plays a significant role in breast cancer invasion, migration, and resistance against targeted therapy and chemotherapy. However, its role in the efficacy of endocrine therapy for the hormone receptor-positive (HR+) breast cancer patients is not known. This study investigated the role of MENA in the resistance against tamoxifen therapy in patients with HR+ breast cancer and the underlying mechanisms. Methods: MENA expression levels in the clinical HR+ breast cancer samples (n = 119) were estimated using immunohistochemistry (IHC) to determine its association with the clinicopathological features, tamoxifen resistance, and survival outcomes. Western blotting (WB) and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis was performed to estimate the MENA protein and mRNA levels in the tamoxifen-sensitive and -resistant HR+ breast cancer cell lines. Furthermore, CCK8, colony formation, and the transwell invasion and migration assays were used to analyze the effects of MENA knockdown on the biological behavior and tamoxifen sensitivity of the HR+ breast cancer cell lines. Xenograft tumor experiments were performed in the nude mice to determine the tumor growth rates and tamoxifen sensitivity of the control and MENA knockdown HR+ breast cancer cells in the presence and absence of tamoxifen treatment. Furthermore, we estimated the growth rates of organoids derived from the HR+ breast cancer patients (n = 10) with high and low MENA expression levels when treated with tamoxifen. Results: HR+ breast cancer patients with low MENA expression demonstrated tamoxifen resistance and poorer prognosis compared to those with high MENA expression. Univariate and multivariate Cox regression analysis demonstrated that MENA expression was an independent predictor of tamoxifen resistance in patients with HR+ breast cancer. MENA knockdown HR+ breast cancer cells showed significantly reduced tamoxifen sensitivity in the in vitro experiments and the in vivo xenograft tumor mouse model compared with the corresponding controls. Furthermore, MENA knockdown increased the in vitro invasion and migration of the HR+ breast cancer cells. HR+ breast cancer organoids with low MENA expression demonstrated reduced tamoxifen sensitivity than those with higher MENA expression. Mechanistically, P-AKT levels were significantly upregulated in the MENA-knockdown HR + breast cancer cells treated with or without 4-OHT compared with the corresponding controls. Conclusions: This study demonstrated that downregulation of MENA promoted tamoxifen resistance in the HR+ breast cancer tissues and cells by enhancing the AKT signaling pathway. Therefore, MENA is a promising prediction biomarker for determining tamoxifen sensitivity in patients with HR+ breast cancer. [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]

Vertical federated learning is designed to protect user privacy by building local models over disparate datasets and transferring intermediate parameters without directly revealing the underlying data. However, the intermediate parameters uploaded by participants may memorize information about the training data. With the recent legislation on the"right to be forgotten", it is crucial for vertical federated learning systems to have the ability to forget or remove previous training information of any client. For the first time, this work fills in this research gap by proposing a vertical federated unlearning method on logistic regression model. The proposed method is achieved by imposing constraints on intermediate parameters during the training process and then subtracting target client updates from the global model. The proposed method boasts the advantages that it does not need any new clients for training and requires only one extra round of updates to recover the performance of the previous model. Moreover, data-poisoning attacks are introduced to evaluate the effectiveness of the unlearning process. The effectiveness of the method is demonstrated through experiments conducted on four benchmark datasets. Compared to the conventional unlearning by retraining from scratch, the proposed unlearning method has a negligible decrease in accuracy but can improve training efficiency by over 400%. [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]

The realization of accurate fault diagnosis is crucial to ensure the normal operation of machines. At present, an intelligent fault diagnosis method based on deep learning has been widely applied in mechanical areas due to its strong ability of feature extraction and accurate identification. However, it often depends on enough training samples. Generally, the model performance depends on sufficient training samples. However, the fault data are always insufficient in practical engineering as the mechanical equipment often works under normal conditions, resulting in imbalanced data. Deep learning-based models trained directly with the imbalanced data will greatly reduce the diagnosis accuracy. In this paper, a diagnosis method is proposed to address the imbalanced data problem and enhance the diagnosis accuracy. Firstly, signals from multiple sensors are processed by the wavelet transform to enhance data features, which are then squeezed and fused through pooling and splicing operations. Subsequently, improved adversarial networks are constructed to generate new samples for data augmentation. Finally, an improved residual network is constructed by introducing the convolutional block attention module for enhancing the diagnosis performance. The experiments containing two different types of bearing datasets are adopted to validate the effectiveness and superiority of the proposed method in single-class and multi-class data imbalance cases. The results show that the proposed method can generate high-quality synthetic samples and improve the diagnosis accuracy presenting great potential in imbalanced fault diagnosis. [ABSTRACT FROM AUTHOR]

Neural tube closure is a dynamic morphogenic event in early embryonic development. Perturbations of this process through either environmental or genetic factors induce the severe congenital malformations known collectively as neural tube defects (NTDs). Deficiencies in maternal folate intake have long been associated with NTDs, as have mutations in critical neurulation genes that include the Grainyhead-like 3 (Grhl3) gene. Mice lacking this gene exhibit fully penetrant thoraco-lumbo-sacral spina bifida and a low incidence of exencephaly. Previous studies have shown that exposure of pregnant mice carrying hypomorphic Grhl3 alleles to exogenous retinoic acid (RA) increases the incidence and severity of NTDs in their offspring. Here, we demonstrate that inhibition of RA signaling using a high affinity pan-RA receptor antagonist administered to pregnant mice at E7.5 induces fully penetrant exencephaly and more severe spina bifida in Grhl3 -null mice. Later administration, although prior to neural tube closure has no effect. Similarly, blockade of RA in the context of reduced expression of Grhl2 , a related gene known to induce NTDs, has no effect. Taken together, these findings provide new insights into the complexities of the interplay between RA signaling and Grhl3 -induced neurulation. • Blockade of retinoic acid at E7.5 induces fully penetrant exencephaly in Grhl3 -null mice. • Blockade of retinoic acid at E7.5 increases the severity of spina bifida in Grhl3 -null mice. • Blockade of retinoic acid in the context of reduced expression of Grhl2 has no effect on Grhl3 -null neural tube closure. [ABSTRACT FROM AUTHOR]

Introducing the exploration of stimulated CD4+ cells adenosine triphosphate (sATPCD4) levels for immune monitoring post non-small cell lung cancer (NSCLC) chemotherapy, the present study aimed to investigate its efficacy in gauging the potential risk of disease progression (PD) in patients with NSCLC. Therefore, a total of 89 patients with advanced NSCLC, who underwent chemotherapy between August 15 2022 and August 30 2023 at the Fifth Affiliated Hospital of Guangzhou Medical University (Guangzhou, China), were retrospectively studied. Patients were divided into the PD (n=21) and disease stability (non-PD; n=68) groups and their clinical data were compared. The thresholds for predicting PD were identified using receiver operating characteristics (ROC) curves. Multivariate logistic regression analysis was carried out to assess the association between peripheral blood markers and the incidence of PD. Therefore, post-chemotherapy, significant differences in white blood cell count, non-stimulated CD4+ cells ATP and sATPCD4 levels were obtained between patients in the PD and non-PD groups (P<0.05). In addition, sATPCD4 levels were notably decreased in the PD group compared with the non-PD group. Furthermore, ROC analysis revealed that the predictive threshold for PD was 224.5 ng/ml [area under the curve=0.887; 95% confidence interval, 0.811–0.963]. Additionally, patients with low immunity (ATP <224.5 ng/ml) exhibited a higher risk of PD compared with the high-immunity group (ATP >224.5 ng/ml; P<0.0001). Finally, multivariate logistic regression analysis suggested that sATPCD4 could serve as an independent factor for predicting NSCLC progression. Overall, the current study predicted that immune function could be possibly associated with the risk of PD in patients with NSCLC. [ABSTRACT FROM AUTHOR]

One of the key materials of interest for p-type oxide semiconductor thin film electronics is cuprous oxide (Cu2O), due to its relatively high hole mobility. In this work, we use experiments, analytical models, and density functional theory calculations to study the scattering mechanisms that determine Hall mobility in two Cu2O samples. First, we examine a polycrystalline Cu2O thin film deposited by RF magnetron sputtering, and second, a single-crystalline Cu2O bulk substrate. Temperature-dependent Hall measurements indicate that neutral impurity and grain boundary scattering are dominant for the polycrystalline Cu2O thin film, while phonon scattering is dominant for single-crystalline Cu2O. Our first-principles calculations show that the room-temperature intrinsic hole mobility of Cu2O is 106 cm2 V−1 s−1, indicating the great promise of the material for p-type electronic devices. This intrinsic mobility is limited by phonon scattering, with the most dominant scattering modes having phonon energies of 88.4 and 17.1 meV. These results indicate that the key pathways to increase the hole mobility in Cu2O thin films are by reducing the impurity concentration and by increasing grain size. Our work thus sets the stage for the future development of high performance Cu2O-based p-type thin film transistors. [ABSTRACT FROM AUTHOR]

Motivation Cryo-Electron Tomography (cryo-ET) is a 3D imaging technology that enables the visualization of subcellular structures in situ at near-atomic resolution. Cellular cryo-ET images help in resolving the structures of macromolecules and determining their spatial relationship in a single cell, which has broad significance in cell and structural biology. Subtomogram classification and recognition constitute a primary step in the systematic recovery of these macromolecular structures. Supervised deep learning methods have been proven to be highly accurate and efficient for subtomogram classification, but suffer from limited applicability due to scarcity of annotated data. While generating simulated data for training supervised models is a potential solution, a sizeable difference in the image intensity distribution in generated data as compared with real experimental data will cause the trained models to perform poorly in predicting classes on real subtomograms. Results In this work, we present Cryo-Shift , a fully unsupervised domain adaptation and randomization framework for deep learning-based cross-domain subtomogram classification. We use unsupervised multi-adversarial domain adaption to reduce the domain shift between features of simulated and experimental data. We develop a network-driven domain randomization procedure with 'warp' modules to alter the simulated data and help the classifier generalize better on experimental data. We do not use any labeled experimental data to train our model, whereas some of the existing alternative approaches require labeled experimental samples for cross-domain classification. Nevertheless, Cryo-Shift outperforms the existing alternative approaches in cross-domain subtomogram classification in extensive evaluation studies demonstrated herein using both simulated and experimental data. Availabilityand implementation https://github.com/xulabs/aitom. Supplementary information Supplementary data are available at Bioinformatics online. [ABSTRACT FROM AUTHOR]

The II-IV-N2 class of heterovalent ternary nitrides has gained significant interest as alternatives to the III-nitrides for electronic and optoelectronic applications. In this study, we apply first-principles calculations based on density functional theory to systematically investigate the effects of structural distortions due to cation size mismatch on the configurational disorder of the cation sublattice and the valence band structure in this class of materials. We find that larger size mismatch between the group-II and the group-IV cations results in stronger lattice distortions from the ideal hexagonal ratio, which in turn inhibits the propensity of these materials toward octet-rule violating cation disorder. We also demonstrate that the formation energy of a single cation antisite pair, which is fast and simple to calculate, is a strong indicator of a material's propensity toward disorder. Furthermore, the breaking of in-plane symmetry leads to a splitting of the top three valence bands at Γ , which is also directly related to the magnitude of structural distortions. Our work demonstrates that the structural and functional properties of the II-IV-N2 materials can be finely tuned through controllable structural distortions that stem from the choice of cations. [ABSTRACT FROM AUTHOR]

Ultrawide-band-gap (UWBG) semiconductors are promising for fast, compact, and energy-efficient power-electronics devices. Their wider band gaps result in higher breakdown electric fields that enable high-power switching with a lower energy loss. Yet, the leading UWBG semiconductors suffer from intrinsic materials' limitations with regard to their doping asymmetry that impedes their adoption in CMOS technology. Improvements in the ambipolar doping of UWBG materials will enable a wider range of applications in power electronics as well as deep-UV optoelectronics. These advances can be accomplished through theoretical insights on the limitations of current UWBG materials coupled with the computational prediction and experimental demonstration of alternative UWBG semiconductor materials with improved doping and transport properties. As an example, we discuss the case of rutile GeO2 (r-GeO2), a water-insoluble GeO2 polytype, which is theoretically predicted to combine an ultra-wide gap with ambipolar dopability, high carrier mobilities, and a higher thermal conductivity than β-Ga2O3. The subsequent realization of single-crystalline r-GeO2 thin films by molecular beam epitaxy provides the opportunity to realize r-GeO2 for electronic applications. Future efforts toward the predictive discovery and design of new UWBG semiconductors include advances in first-principles theory and high-performance computing software, as well as the demonstration of controlled doping in high-quality thin films with lower dislocation densities and optimized film properties. [ABSTRACT FROM AUTHOR]

Lanthanum nitride (LaN) has attracted research interest in catalysis due to its ability to activate the triple bonds of N2 molecules, enabling efficient and cost-effective synthesis of ammonia from N2 gas. While exciting progress has been made to use LaN in functional applications, the electronic character of LaN (metallic, semi-metallic, or semiconducting) and magnitude of its bandgap have so far not been conclusively determined. Here, we investigate the electronic properties of LaN with hybrid density functional theory calculations. In contrast to previous claims that LaN is semi-metallic, our calculations show that LaN is a direct-bandgap semiconductor with a bandgap value of 0.62 eV at the X point of the Brillouin zone. The dispersive character of the bands near the band edges leads to light electron and hole effective masses, making LaN promising for electronic and optoelectronic applications. Our calculations also reveal that nitrogen vacancies and substitutional oxygen atoms are two unintentional shallow donors with low formation energies that can explain the origin of the previously reported electrical conductivity. Our calculations clarify the semiconducting nature of LaN and reveal candidate unintentional point defects that are likely responsible for its measured electrical conductivity. [ABSTRACT FROM AUTHOR]

This work reports a new methodology for naked-eye nanosensing of Hg2+ where the Tyndall effect of gold nanoparticles (GNPs) acts as a light scattering signalling readout. Its utility is demonstrated with ultrasensitive detection of the target with a limit down to 0.13 nM (∼5461-fold sensitivity improvement over conventional GNP-based methods with surface plasmon resonance signalling). [ABSTRACT FROM AUTHOR]

A fundamental understanding and control of impurity incorporation and charge carrier recombination are critical for emerging ScxAl1−xN electronics, optoelectronics, and photonics. We report on the photoluminescence properties of ScxAl1−xN grown by plasma-assisted molecular beam epitaxy with varying growth temperatures and Sc contents. Bright and broad emission comprising a dominant peak at ∼3.52 eV and a weak peak at ∼2.90 eV was observed in Sc0.05Al0.95N. The origin of the ∼3.52 eV emission line is attributed to charge carrier recombination from the localized excited state of (Vcation-ON)2−/− to its ground state, whereas the second peak at ∼2.90 eV results from charge carrier recombination of isolated V cation 3 − / 2 − to the valence band. We further show that oxygen defect-related emission can be significantly suppressed by increasing growth temperature. This work sheds light on the recombination dynamics of photoexcited carriers in ScxAl1−xN and further offers insight into how to improve the optical and electrical properties of ScxAl1−xN that are relevant for a broad range of applications. [ABSTRACT FROM AUTHOR]

The stacking of 2D perovskites on the top of 3D perovskites has been recognized as a promising interfacial treatment approach to improve the stability and efficiency of planar perovskite solar cells (PSCs). However, traditional 2D–3D perovskite heterojunctions obtained from the high-temperature annealing process still exhibit unsatisfactory charge transfer performance and interfacial voltage loss. Herein, we introduce isopentylammonium iodide (PNAI) as the large organic ammonium salt, and adjust the in situ grown processes of 2D perovskites by thermal treatments to form a multi-component capping layer composed of 2D perovskites with plenty of high n-value 2D phases (n ≥ 3, n is the number of inorganic layers) and residual PNAI molecules on 3D perovskites. Such an optimized composition for a 2D–3D perovskite heterojunction can remarkably improve the charge transfer performance, further suppress the interfacial ionic defects, and enlarge Fermi-level splitting, leading to a low bandgap-to-voltage loss (0.38 V). Consequently, this treatment strategy significantly improves the efficiency of planar PSCs to 22.62% with an outstanding open-circuit voltage of 1.16 V. Moreover, the unencapsulated PNAI-90 treated device stored under a relative humidity of 30 ± 5% for 1000 h still retains 89% of its initial PCE. This work offers a new strategy to construct a robust 2D–3D heterojunction for planar PSCs. [ABSTRACT FROM AUTHOR]

We calculate the alloy-disorder-limited electron mobility of AlxGa1−xN from first principles. AlxGa1−xN is a technologically important ultra-wide-bandgap alloy with promise in light emitting diodes and high-power transistors. Alloying introduces statistical disorder, which causes electrons to scatter between different crystal-momentum states, leading to a reduction in mobility for intermediate alloy compositions. The corresponding lifetime, which appears as an energy broadening in the band structure, can be evaluated by unfolding the band structure from the supercell basis to the primitive-cell basis. We fit the first-principles band broadening with a model scattering potential and evaluate the low-field electron mobility using the semiclassical Boltzmann transport equation in the relaxation-time approximation. Our calculated mobility is in agreement with experimental values. We also find the lowest alloy-scattering electron mobility (total electron mobility) across the entire composition range to be 186 c m 2 / V s (136 c m 2 / V s), which is comparable to the highest electron mobility predicted in the competitor system, β- (Al x Ga 1 − x) 2 O 3 . Our results elucidate the intrinsic limits imposed by alloy disorder on electron transport in AlxGa1−xN. [ABSTRACT FROM AUTHOR]

This paper initially describes a nanosensor for fluorescence detection of Al3+ ions by using graphene quantum dots (GQDs) that are synthesized via microwave-assisted single-step ring-closure condensation of glucose molecules. The one-pot synthesis strategy based on the microwave radiation could be finished in several minutes and no post-modification of the GQDs was required. In particular, the GQD nanoprobes showed a sensitive and specific fluorescence enhancement response to Al3+. The involved mechanism might be the Al3+-mediated aggregation of the GQDs leading to aggregation-induced enhanced emission (AIEE). Under optimal conditions, this new fluorescent nanosensor was able to quantitatively detect Al3+ in a linear concentration range of 0.4–500 μM. The limit of detection was estimated to be ∼59.8 nM according to the 3σ rule, which made it be among the most sensitive systems currently available for sensing the target ion. Moreover, satisfactory recovery results (ranging from 96.8 to 109.7%) of analyzing a set of real water examples additionally validated its accuracy for practical applications. Considering its simplicity, high sensitivity and specificity, low cost, and good reliability, the developed fluorescent nanosensing system for Al3+ holds great promise for broad uses in water safety, environmental monitoring, and waste management. [ABSTRACT FROM AUTHOR]

Mask optimization has been a critical problem in the VLSI design flow due to the mismatch between the lithography system and the continuously shrinking feature sizes. Optical proximity correction (OPC) is one of the prevailing resolution enhancement techniques (RETs) that can significantly improve mask printability. However, in advanced technology nodes, the mask optimization process consumes more and more computational resources. In this article, we develop a generative adversarial network (GAN) model to achieve better mask optimization performance. We first develop an OPC-oriented GAN flow that can learn target-mask mapping from the improved architecture and objectives, which leads to satisfactory mask optimization results. To facilitate the training process and ensure better convergence, we propose a pretraining scheme that jointly trains the neural network with inverse lithography technique (ILT). We also propose an enhanced generator design with a U-Net architecture and a subpixel super-resolution structure that promise a better convergence and a better mask quality, respectively. At convergence, the generative network is able to create quasi-optimal masks for given target circuit patterns and fewer normal OPC steps are required to generate high quality masks. The experimental results show that our flow can facilitate the mask optimization process as well as ensure a better printability. [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]

The emulsification of amphiphilic polymer is inevitably affected by the salinity environment in the preparation and flooding process. The variation of emulsions in stability and rheology has a significant influence on the efficiency of polymer flooding. Thus, the effect of NaCl and CaCl2 on the emulsification behavior of hydrophobically modified polyacrylamide (HMPAM) was investigated. A novel dynamic multiple light scattering method was proposed to analyze the variation of emulsion stability. Then, the emulsions with addition of salt were systematically researched in terms of oil droplet size, polymer adsorption, and rheology properties. With the increase of NaCl concentration, the emulsion stability with 1500 mg L−1 HMPAM (above the critical aggregation concentration) decreases monotonically; with the increase of CaCl2 concentration, the emulsion stability rises at first then decreases. It is found that the structural viscosity of the polymer solution is the dominant factor in stabilizing the crude oil emulsion. Modulation effect of the salt ions on the emulsion stability is achieved by regulating the aggregate structure in the aqueous solution. Oscillation-shear-oscillation rheological experiments were conducted to investigate the rheological properties of emulsions. The results show that the viscoelasticity of emulsion system at high salt concentration decreases after high-rate shearing and the recovery of the viscoelasticity is slowed down due to the inhibition of hydrophobic association. This study provides theoretical guidance for elucidating the regulation rules and mechanism of salts on the amphiphilic polymer-containing crude oil emulsions. [ABSTRACT FROM AUTHOR]

Skeletal muscle atrophy in chronic kidney disease (CKD) leads to a decline in quality of life and increased risk of morbidity and mortality. We have obtained evidence that oxidative stress is essential in the progression of CKD-related muscle atrophy. Whether Saikosaponin A and D, two emerging antioxidants extracted from Bupleurum chinense DC, alleviate muscle atrophy remains to be further studied. The purpose of this study was to investigate the effects and mechanisms of these two components on CKD complicated with muscle atrophy. In this research, muscle dystrophy model was established using 5/6 nephrectomized mice in vivo and in vitro with Dexamethasone (Dex)-managed C2C12 myotubes. The results of RNA-sequencing showed that exposure to Dex affected the antioxidant activity, catalytic activity and enzyme regulator activity of C2C12 cells. According to KEGG analysis, the largest numbers of differentially expressed genes detected were enriched in the PI3K/AKT pathway. In vivo , Saikosaponin A and D remain renal function, cross-section size, fiber-type composition and anti-inflammatory ability. These two components suppressed the expression of MuRF-1 and enhanced the expression of MyoD and Dystrophin. In addition, Saikosaponin A and D maintained redox balance by increasing the activities of antioxidant enzymes while inhibiting the excessive accumulation of reactive oxygen species. Furthermore, Saikosaponin A and D stimulated PI3K/AKT and its downstream Nrf2 pathway in CKD mice. The effects of Saikosaponin A and D on increasing the inner diameter of C2C12 myotube, reducing oxidative stress and enhancing expression of p-AKT, p-mTOR, p70S6K, Nrf2 and HO-1 proteins were observed in vitro. Importantly, we verified that these protective effects could be significantly reversed by inhibiting PI3K and knocking out Nrf2. In summary, Saikosaponin A and D improve CKD-induced muscle atrophy by reducing oxidative stress through the PI3K/AKT/Nrf2 pathway. [Display omitted] [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]