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Levulinic acid (LA) aqueous-phase hydrogenation into γ-valerolactone (GVL) is considered one of the pivotal reactions to convert biomass into renewable chemicals. Here we have deposited Pt on TiO 2 nanofilm coated α-Al 2 O 3 via atomic layer deposition (ALD) to synthesize Pt-TiO 2 /α-Al 2 O 3. This catalyst shows excellent activity and stability (1000 h) in LA hydrogenation compared to Pt/α-Al 2 O 3. By excluding the effect of Pt particle size, lattice plane, support morphology, pore structure, and electronic state, the critical role of Pt-TiO 2 interaction is revealed by various characterization methods. CO diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and in-situ Fourier transform Infrared spectra (FTIR) results indicate that Pt-TiO 2 interaction provides new interfacial Pt sites for LA and intermediate adsorption and Ti-OH active sites for LA dehydration cyclization to α-angelica lactone intermediate, which leads to the shift of reaction pathways from direct LA C O hydrogenation lactonization on Pt/α-Al 2 O 3 to LA dehydration cyclization and hydrogenation on Pt-TiO 2 /α-Al 2 O 3。 It provides insight into the design of high-efficient catalysts for aqueous-phase hydrogenation. [Display omitted] • The critical role of Pt-TiO 2 interaction is revealed by excluding the effect of Pt structures. • Pt-TiO 2 interaction provides interfacial Pt sites and Ti-OH sites for LA dehydration cyclization. • Pt-TiO 2 interaction cause the shift of reaction pathways for LA hydrogenation. [ABSTRACT FROM AUTHOR]

[Display omitted] • This work confirms that the isolated –OH groups are the nucleation sites of Pt ALD. • The carbonates on the surface of γ-Al 2 O 3 are explored to be not impurities as always considered. The removal of carbonates during the thermal treatment is able to induce the generation of isolated –OH groups. It is crucial to attain a sufficient surface distribution density of metal nanoparticles to achieve high catalytic performance in oxide-supported metal catalysts. Atomic layer deposition (ALD) is a powerful technique for preparing supported nanocatalysts to precisely regulate the metal particle size, structure and distribution in nanoscale. Not only suitable ALD deposition parameters, but also supports with sufficient ALD nucleation sites on the surface are required when using ALD to synthesize supported metal particles with ultrafine size and ultrahigh density. How to regulate the surface nucleation sites to acquire metal nanoparticles with high surface density and elucidating the mechanism are of great importance. Herein, we present a simple thermal treatment approach to activate the surface of γ-Al 2 O 3 , significantly enhancing the Pt loading and the density of Pt nanoparticles compared to raw γ-Al 2 O 3 under identical deposition conditions. Detailed mechanism investigations reveal that removing carbonates on the surface of γ-Al 2 O 3 during thermal treatment induces the generation of isolated –OH groups, which are verified to be nucleation sites of Pt ALD. The increase in the number of isolated –OH and its high reactivity towards anchoring Pt precursor molecules in ALD reaction both contribute to a high density of Pt nanoparticles. This work provides a novel approach to promote Pt ALD nucleation on the surface of γ-Al 2 O 3 and an in-depth understanding of the mechanism for the nucleation promotion, which can be applied to other oxide supports. [ABSTRACT FROM AUTHOR]

SUMMARY: In this study, magnitude estimation in earthquake early warning (EEW) systems is seen as a classification problem: the single-channel waveform, starting from the P-wave onset and lasting 4 s, is given in the input, and earthquake severity (medium and large earthquakes: local magnitude (ML) ≥ 5; small earthquakes: ML < 5) is the classification result. The convolutional neural network (CNN) is proposed to estimate the severity of the earthquake, which is composed of several blocks that can extract the latent representation of the input from different receptive fields automatically. We train and test the proposed CNN model using two data sets. One is recorded by the China Earthquake Networks Center (CENC), and the other is the Stanford Earthquake Dataset (STEAD). Accordingly, the proposed CNN model achieves a test accuracy of 97.90 per cent. The proposed CNN model is applied to estimate two real-world earthquake swarms in China (the Changning earthquake and the Tangshan earthquake swarms) and the INSTANCE data set, and demonstrated the promising performance of generalization. In addition, the proposed CNN model has been connected to the CENC for further testing using real-world real-time seismic data. [ABSTRACT FROM AUTHOR]

In this paper, an efficient two-step convolutional neural network (CNN) procedure is proposed to estimate earthquake magnitude using raw waveform data up to only 4 s after the P wave onset. In the proposed procedure, magnitude estimation is split into classification task and regression task. The classification task trains a CNN model to estimate the magnitude range by employing unsure responses that represent the classification decision boundary. In addition, the regression task trains two CNN models to estimate the specific magnitudes of large and small earthquakes, respectively. After training, the classification model achieves an accuracy of 98.63%. The mean absolute error (MAE) of the large earthquake regression and the small earthquake regression models are 0.26 and 0.46, respectively. The ideology behind the two-step procedure effectively address two main issues in earthquake early warning (EEW) systems: reducing missed alert caused by seismometer saturation and improving the accuracy of estimating specific magnitudes. Currently, this procedure has been connected to China Earthquake Networks Center (CENC) for real-time monitoring. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd/CeO 2 catalysts with a stable high Pd2+/(Pd0 + Pd2+) ratio are prepared by ALD. • Pd/CeO 2 catalysts exhibit excellent performance in benzyl alcohol oxidation. • The TOFs exhibit a volcano relationship with the Pd2+/(Pd0 + Pd2+) ratio. • A dual-site catalyzed oxygen-promoted β-H elimination mechanism was proposed. Solvent-free aerobic oxidation of benzyl alcohol is a green approach for synthesizing fine chemicals. Pd-based catalysts are extensively investigated due to their excellent catalytic activity compared to other metal catalysts. Most researchers believe that metallic Pd species (Pd0) provide active centers. However, the critical role of active oxygen and the function of Pd2+ is neglected. Herein, supported Pd clusters on CeO 2 (Pd/CeO 2) with a stable high Pd2+/(Pd0 + Pd2+) ratio are prepared by atomic layer deposition (ALD). The turnover frequency (TOF) and activity on as-prepared Pd/CeO 2 catalysts in solvent-free aerobic oxidation of benzyl alcohol reach 3.50 × 105 h−1 and 1.85 × 105 mol/(mol Pd ·h), respectively, which are much superior to previously reported results. As the Pd loading increases, the TOFs exhibit a volcano relationship with the Pd2+/(Pd0 + Pd2+) ratio, pointing to a dual Pd0 and Pd2+ sites catalyzed mechanism. O 2 kinetic isotopic effect and further evidence support a dual-site catalyzed oxygen-promoted β-hydride elimination mechanisms, in which benzyl alcohol is selectively adsorbed to Pd2+ sites and reacts with active oxygen species on nearby Pd0 sites during the reaction. [ABSTRACT FROM AUTHOR]

Background: Retinoblastoma (RB) is the most common intraocular malignancy in children. Long non-coding RNA X-inactive specific transcript (lncRNA XIST) has been reported to be associated with RB, but research on the mechanism of XIST is not well studied. Methods: Expressions of XIST, microRNA-140-5p (miR-140-5p), and sex-determining region Y-related high-mobility group box 4 (SOX4) were analyzed by qRT-PCR or Western blot. Relationships of XIST, SOX4, and miR-140-5p were evaluated by dual-luciferase reporter assay and Spearman's analysis. Cell Counting Kit-8 (CCK-8) and Transwell assay were performed to assess the function of XIST on RB cell proliferation and invasion. Results: In RB tissues, XIST and SOX4 expressions were obviously increased, but the miR-140-5p expression was markedly reduced. XIST expression was positively related to SOX4 expression while negatively correlated with miR-140-5p expression, and negative correlation was exhibited between miR-140-5p and SOX4 expression in RB tissues. XIST was confirmed to directly bind to miR-140-5p, and SOX4 was one target of miR-140-5p. XIST knockdown could impede RB cell proliferation and invasion, while miR-140-5p inhibition reversed the effects. In addition, XIST overexpression or miR-140-5p inhibition could abrogate the inhibition of SOX4 silencing on cell proliferation and invasion of RB cells. Conclusions: XIST was obviously increased in RB tissues and cells, and XIST inhibition repressed the proliferation and invasion of RB cells by miR-140-5p/SOX4 axis, which may provide new understandings of the XIST molecular mechanism in RB. [ABSTRACT FROM AUTHOR]

A multi-task learning-based focal mechanism network (MTFMN) is proposed for calculating parameters of the focal mechanism of earthquakes by regression with incorporating expert prior knowledge. The model automatically learns feature representations of seismic waveforms and transforms the inversion task of the focal mechanism into multi-task learning. Experimental results suggest that MTFMN outperforms traditional methods in the task of earthquake focal mechanism and improves the accuracy of parameter estimation of focal mechanism. In addition, comparative experiments demonstrate MTFMN's enhanced robustness and generalization capabilities compared to other methods. Our proposed methodology presents a more precise regression approach for focal mechanism inversion, with the potential to provide a better understanding of seismic events. • Solving the focal mechanism using an end-to-end model. • Incorporating expert knowledge in deep learning models. • A soft-shared multi-task learning model is used to improve model performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Singly dispersed Ru atoms are anchored on the ceria support of various shapes. • The electronic states of Ru atoms are regulated by different crystal planes of ceria. • Ru/CeO 2 (nanorods) exhibits the highest selectivity of 97.6 % to CO at 350 °C. • The cationic Ruβ sites with weak affinity for CO leads to high CO selectivity. • The low valence Ruα sites with strong H 2 dissociation ability leads to high activity. Harnessing the selectivity in catalytic hydrogenation of CO 2 is important for producing valuable chemicals. Herein, the shape dependency of the CO 2 hydrogenation on singly dispersed Ru/CeO 2 catalysts is investigated. CeO 2 of three shapes, including nanocube, nanooctahedron and nanorod, are prepared as the catalyst supports and assigned to the surface of (100), (111) and (110) crystal plane, respectively. The Ru/CeO 2 (nanorod) exhibits the highest selectivity to CO (97.6 %) at 350 °C, while the Ru/CeO 2 (nanocube) exhibits a mediocre selectivity to CO (41.4 %) but the highest CO 2 conversion. The shape of the CeO 2 support determines the electronic state of supported Ru atoms through the electronic metal-support interaction. The low CO affinity on cationic Ruβ sites leads to the higher selectivity to CO on the Ru/CeO 2 (nanorod) and Ru/CeO 2 (nanooctahedron) catalysts, while the strong dissociation ability of H 2 on low valence Ruα sites results in the high activity on the Ru/CeO 2 (nanocube) catalyst. [ABSTRACT FROM AUTHOR]

Effect and clinical efficacy of magnesium sulfate combined with phentolamine on homocysteine and C-reactive protein in the serum of patients with pregnancy-induced hypertension syndrome were investigated. A total of 96 patients with pregnancy-induced hypertension syndrome who were diagnosed and treated in Jining No. 1 People's Hospital from February 2016 to January 2018 were retrospectively analyzed. The patients were grouped according to the dosage regimen. The patients who received the combination treatment of magnesium sulfate and phentolamine on the basis of magnesium sulfate were included in the observation group, and the patients who were treated with the intravenous infusion of magnesium sulfate alone were included in the control group. Mean arterial pressure (MAP), the content of 24 h urine protein, systolic blood pressure (SBP), diastolic blood pressure (DBP), Hcy, and CRP of the pregnant women were observed. MAP and the content of 24 h urine protein, SBP and DBP of the patients in the observation group after the treatment were significantly lower than those of the patients in the control group (P<0.001). Hcy and CRP of the patients in the observation group after the treatment were significantly lower than those of the patients in the control group (P<0.001). The total effective rate of the patients in the observation group was significantly higher than that of the patients in the control group (P<0.05). In conclusion, the meliorative effect of magnesium sulphate combined with phentolamine on the level of MAP, the content of 24 h urine protein, SBP, DBP, Hcy and CRP in pregnant woman had a greater impact than that of the single use of the intravenous infusion of magnesium sulfate in the treatment of pregnancy-induced hypertension syndrome, and the clinical efficacy of magnesium sulphate combined with phentolamine was better, thus worthwhile to promote widely in clinic. [ABSTRACT FROM AUTHOR]