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Abstract In the design and optimisation of marine wireless communication and navigation systems, a thorough investigation of radio wave propagation characteristics under atmospheric ducting conditions is essential. The authors aim to enhance the efficiency of radio wave propagation loss prediction in marine atmospheric ducting environments, proposing a prediction model based on Fast Reordered‐Alternate Direction Decomposition (FR‐ADD). By approximating the diffraction term into three independent components, exploiting the commutative properties of the Fourier transform to reduce the spatial dimensions, and incorporating a rapid algorithm for the parabolic equation, the model optimises the stepping process and significantly improves computational efficiency. Simulation experiments demonstrate that, in the long‐distance and complex marine ducting environments, the model not only maintains prediction accuracy but also substantially reduces computational load and prediction time, effectively realising over‐the‐horizon propagation prediction. In the experiment of radio wave propagation characteristics in the Yellow and Bohai Seas, the simulation data from the FR‐ADD model showed significant correlation with actual measurements and simulations from the AREPS software, confirming the method's efficiency and practicality.

This paper adds an organizational dimension to the body of literature on international student mobility. Existing studies examine push/pull factors and student motivations, neglecting that students' motivations and demands are not necessarily spontaneous, but can be shaped by external forces. Drawing on interview, archival and observation data collected on four leading cram schools that prepare students for the TOEFL/GRE, IELTS and SAT in China, I argue that cram schools not only coach students on test preparation and "how to study abroad," but they also adopt organizational framing to instill in students "why to study abroad." Leading cram schools have played an integral role in promoting a certain organizational framing as the dominant approach of a niche market in a given era. During the 1990s, when the TOEFL/GRE niche market was rapidly expanding, the market leader in this niche promoted self-help and nationalism as dominant discourses. Self-help discourse frames overseas study and test preparation not as means, but as the ends of students' lives: going beyond one's limit and making one's life complete. Nationalist discourse depicts overseas study as a detour to build a stronger China after learning from the West. After 2000, however, new organizational framing picked up momentum in the new niche markets of IELTS and SAT. Targeting urban middle-class consumers, market leaders in these new niches increasingly framed studying abroad as a springboard for immigration, a channel for becoming global elites and an opportunity for status improvement for the entire family. My article bridges literature on transnational higher education with studies on supplementary education.

The performance of metal sites in terms of their formation, evolution, and deactivation is strongly influenced by the properties of the supports during catalysis. Nanomaterials offer a tailorable size, shape, and composition, along with a large surface area, a high fraction of surface atoms, and unique electronic properties, thereby significantly improving the efficiency, selectivity, stability, and versatility of catalytic processes. In the direct dehydrogenation of propane (PDH) reactions, the activity, selectivity, and durability of catalysts face challenges due to the high reaction temperature and harsh atmosphere that accompanies the presence of reducible reactants. Herein, bimetallic platinum–zinc (PtZn) sites were synthesized on various silica nanomaterials to investigate the correlation between the nanoscale properties of silica and PDH performance. Among the supports being explored, including amorphous SiO2 particles, mesoporous SBA-15, microporous silicate-1, and mesoporous MCM-41, MCM-41 stood out due to its distinctive advantages, including a large specific surface area, well-portioned pore size and distribution, and an appropriate amount and strength of acidic sites. Operating at a temperature of 600 °C, the catalyst exhibited a notable propene production rate of approximately 37.3 mmol·gcat–1·h–1. This performance was coupled with an outstanding initial conversion (39.2%) and selectivity (97.7%) during the PDH reaction. The characterization results highlighted the exceptional dispersion of the PtZn sites on the MCM-41 support, showing remarkable resistance to coking and sintering throughout the reaction. These attributes exceeded those observed in other silica supports. [ABSTRACT FROM AUTHOR]

BACKGROUND: Atherosclerotic renal artery stenosis (ARAS) is a common disease in the elderly population. OBJECTIVE: The aim was to develop a contrast-enhanced ultrasound (CEUS)-based model for predicting post-angioplasty improvement in hypertension in patients with severe ARAS. METHODS: Thirty-five patients with severe ARAS (⩾ 70%) were included in this study, and 42 renal arteries received percutaneous transluminal renal arterial stenting. An optimal integral formula was developed from pre-interventional color-coded duplex sonography (CCDS) and CEUS parameters using least absolute shrinkage and selection operator (LASSO) regression and receiver operating characteristic (ROC) curve analysis. A model for predicting short-term hypertension improvement was established using the integral formula and clinical risk factors. Bootstrapping was used for internal validation. RESULTS: Two integral formulas, LASSO.CCDS and LASSO.CEUS, were established. ROC curves of the two integral formulas showed that LASSO.CEUS was the better formula for predicting hypertension improvement (AUC 0.816, specificity 78.6%). Univariate and multivariate regression analyses showed that duration of hypertension (OR 0.841, P = 0.027), diabetes (OR = 0.019, P = 0.010), and LASSO.CEUS (OR 7.641, P = 0.052) were predictors of short-term hypertension improvement after interventional therapy. Using LASSO.CEUS combined with clinical risk factors, the following prediction model was established: logit (short-term improvement in hypertension) = 1.879–0.173 × hypertension duration – 3.961 × diabetes + 2.034 × LASSO.CEUS (AUC 0.939). CONCLUSIONS: The model established using CEUS parameters and clinical risk factors could predict hypertension improvement after interventional therapy, but further research and verification are needed. [ABSTRACT FROM AUTHOR]

The formed morphology during phase separation is crucial for determining the properties of the resulting product, e.g., a functional membrane. However, an accurate morphology prediction is challenging due to the inherent complexity of molecular interactions. In this study, the phase separation of a two-dimensional model polymer solution is investigated. The spinodal decomposition during the formation of polymer-rich domains is described by the Cahn–Hilliard equation incorporating the Flory–Huggins free energy description between the polymer and solvent. We circumvent the heavy burden of precise morphology prediction through two aspects. First, we systematically analyze the degree of impact of the parameters (initial polymer volume fraction, polymer mobility, degree of polymerization, surface tension parameter, and Flory–Huggins interaction parameter) in a phase-separating system on morphological evolution characterized by geometrical fingerprints to determine the most influential factor. The sensitivity analysis provides an estimate for the error tolerance of each parameter in determining the transition time, the spinodal decomposition length, and the domain growth rate. Secondly, we devise a set of physics-informed neural networks (PINN) comprising two coupled feedforward neural networks to represent the phase-field equations and inversely discover the value of the embedded parameter for a given morphological evolution. Among the five parameters considered, the polymer–solvent affinity is key in determining the phase transition time and the growth law of the polymer-rich domains. We demonstrate that the unknown parameter can be accurately determined by renormalizing the PINN-predicted parameter by the change of characteristic domain size in time. Our results suggest that certain degrees of error are tolerable and do not significantly affect the morphology properties during the domain growth. Moreover, reliable inverse prediction of the unknown parameter can be pursued by merely two separate snapshots during morphological evolution. The latter largely reduces the computational load in the standard data-driven predictive methods, and the approach may prove beneficial to the inverse design for specific needs. [ABSTRACT FROM AUTHOR]

Supported metal (oxide) clusters, with both rich surface sites and high atom utilization efficiency, have shown improved activity and selectivity for many catalytic reactions over nanoparticle and single atom catalysts. Yet, the role of cluster catalysts has been rarely reported in CO2 electroreduction reaction (CO2RR), which is a promising route for converting CO2 to liquid fuels like formic acid with renewable electricity. Here we develop a bismuth oxide (BiOn) cluster catalyst for highly efficient CO2RR to formate. The BiOn cluster catalyst exhibits excellent activity, selectivity, and stability towards formate production, with a formate Faradaic efficiency of over 90% at a current density up to 500 mA·cm−2 in an alkaline membrane electrode assembly electrolyzer, corresponding to a mass activity as high as 3,750 A·gBi−1. The electrolyzer with the BiOn cluster catalyst delivers a remarkable formate production rate of 0.56 mmol·min−1 at a high single-pass CO2 conversion of 44%. Density functional theory calculations indicate that Bi4O3 cluster is more favorable for stabilizing the HCOO* intermediate than Bi(001) surface and single site BiC4 motif, rationalizing the improved formate production over the BiOn cluster catalyst. This work highlights the great importance of cluster catalysts in activity and selectivity control in electrocatalytic CO2 conversion. [ABSTRACT FROM AUTHOR]

Tuning an oxide/metal interface is of critical importance for the performance enhancement of many heterogeneous catalytic reactions. However, catalytic oxidation occurring at the interface between non-reducible oxide and metal has been challenging, since non-reducible oxides hardly lose their lattice oxygen (OL) or dissociate O2 from the gas phase. In this work, a ZnO monolayer film on Au(111) is used as an inverse catalyst to investigate CO oxidation occurring at the ZnO/Au(111) interface via high pressure scanning tunneling microscopy. Surface science experiments indicate that oxygen intercalation under the ZnO monolayer film, termed ZnO/O/Au(111), can be achieved via a surface reaction with 1 × 10−6 mbar O3. Subsequent exposure of the formed ZnO/O/Au(111) surface to mbar CO at room temperature leads to the recovery of the pristine ZnO/Au(111) surface. Theoretical calculations reveal that OL adjacent to intercalated oxygen (Oint) is activated due to the OL–Zn–Oint bonding and surface corrugation, which can be directly involved in CO oxidation. Subsequently, Oint migrates to the formed oxygen vacancy from the subsurface resuming the pristine ZnO structure. These results thus reveal that oxygen intercalation underneath single-layer ZnO will strongly boost the oxidation reaction via activating adjacent lattice oxygen atoms. [ABSTRACT FROM AUTHOR]

Understanding the effect of H2O adsorption on reactant activation is of great importance in heterogeneous catalysis, which remains a grand challenge particularly in oxide catalyst systems with structural complexity. Herein, the effect of D2O adsorption on D2 activation over MgO nanocatalysts at different temperatures has been investigated by transmission Fourier transform infrared (FT-IR) and temperature-programmed desorption (TPD). Two sets of hydride and hydroxyl species produced from D2 dissociation at more active and less active Mg-O pairs can be observed by FT-IR, which all desorb via the product of D2 as confirmed by TPD experiments. We find that the physically adsorbed D2O overlayer does not affect the dissociation of D2 since D2 may pass through the molecular layer and access the surface-active sites. When D2O is partially dissociated on the MgO surface, D2 can only dissociate at the remaining active sites until that dissociated −ODw groups from D2O occupy all active sites. These findings provide a fundamental understanding of the effect of water adsorption on D2 activation on oxide catalysts. [ABSTRACT FROM AUTHOR]

Introduction: DNA methylation regulates gene transcriptional functions in the pathogenesis of malignant diseases. In prostate cancer, several tumor suppressors are known to be tumor specifically methylated. Methods: In this study, 450K methylation data and mRNA expression data were accessed from The Cancer Genome Atlas-Prostate Adenocarcinoma database and analyzed bioinformatically. Methylation-specific PCR was used to examine the methylation condition in AOX1 promoter. qRT-PCR was applied to measure the mRNA expression of AOX1. Western blot was employed to detect the expressions of AOX1 and the EMT associated proteins. Transwell and scratch healing assays were used to examine the invasive and migratory abilities of the prostate cancer cells respectively. Results: AOX1 was lowly expressed and hypermethylated in the prostate cancer tissues and cells. Also, AOX1 was downregulated at protein level in prostate cancer cells. Knocking down AOX1 could promote cell migration and invasion in the prostate cancer cells. By using a DNA methylation inhibitor, 5-AzadC was found to promote the expression of AOX1 and reverse the promoting effects of short interfering RNA against AOX1 on cell migration and invasion. Conclusion: This study suggested that DNA methylation and low AOX1 level might be biomarkers for prostate cancer. [ABSTRACT FROM AUTHOR]

We study whether investor voice affects firm policy. Using a novel dataset of the transcripts of online earnings communication conferences (OECC) of Chinese listed firms during 2006 and 2015, we show that firms do respond to investor complaints about dividend policy with increased future dividends. We find that the number of dividend‐related questions raised by investors, the number of complaints (questions with negative attitudes), firm executive responsiveness, and CEO attendance in the OECC are positively associated with future dividend payouts. Moreover, positive responses are concentrated in firms facing greater pressure from peers, the market, and the regulator. Our additional analysis shows that the increase in payouts in response to investors' voice is not at the expense of cutting value‐increasing investment. Overall, our results suggest that the online interactive platform empowers shareholders' voice and helps them to conduct a successful dialogue with firm managers in a cost‐effective way. [ABSTRACT FROM AUTHOR]