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Modulating the microenvironment of single-metal active sites holds excellent promises for developing highly efficiently oxygen electrocatalysts. Herein, by combining theoretical predictions and experiments, we reported a general strategy to engineer the electronic properties of iron-nitrogen-carbon (FeN

The first-principles calculations demonstrate that covalently bonded (cb) heterojunction and van der Waals (vdW) heterojunction can coexist in silicene/CeO2 heterojunctions, due to the different stacking patterns. Especially, the cb heterojunction with band gap of 1.97 eV, forms a type-II heterojunction, exhibits good redox performance and has high-effective optical absorption spectra, thus it is a promising photocatalyst for overall water splitting. Besides, for the vdW heterojunction, the Dirac cone of silicene is well kept on CeO2 semiconducting substrate, with a considerable energy gap of 0.43 eV, which can be an ideal material in building silicene-based electronic device. These results may open a new gateway in both of nanoelectronic device and energy conversion for silicene/CeO2 nanocomposites.

Grain is not only the basic living materials of urban and rural residents, but an important strategic resource related to the national security. Therefore, grain security is an important aspect of national security. Farmers' willingness to grow grain is the key factor to guarantee food security. Based on the structural equation model, the main factors that influence the farmers' willingness to grow grain were studied in this paper by investigating 486 dispersed farmers in six counties (cities, districts) of three prefecture-level cities in Shandong Province. The study indicated that aside from the difficulty of measuring the influence of personal characteristic factors, the national grain subsidy policies, grain price, grain planting scale, other farmers' production behaviors, and promotion of agricultural technology affected the farmers' willingness to grow grain in varying degrees. Further regional multi-group analyses demonstrated that the farmers' willingness to grow grain showed an increasing trend from east to west in Shandong Province. Additionally, grain subsidy policies and family characteristic factors had obvious regional differences on the farmers' willingness to grow grain. Therefore, optimizing and improving the national grain subsidy policies, encouraging the management of a moderate scale, stabilizing prices of grain, increasing the propaganda of agricultural information and promoting agricultural technology were the key factors to increase the farmers' willingness to grow grain.

Limited data are available on the prognostic role of Ki-67 changes in residual tumors after neoadjuvant chemotherapy in primary inflammatory breast cancer (IBC) patients treated with trimodality therapy. This study aims to evaluate changes in Ki-67 associated with disease-free survival (DFS) and overall survival (OS) in IBC patients without pathological complete response.We identified a cohort of primary IBC patients with matched pre- and posttreatment samples treated with anthracycline and taxane-based regimen. All patients had a pathological evaluation, including ER, PR, HER2 status, and Ki-67 expression performed both at diagnostic core biopsy and at final surgery. Kaplan-Meier and Cox proportional hazards methods were used to assess DFS and OS rates and their relationship with clinicopathological features.Two hundred and ten patients with stage III IBC were included. Sixty-three percent of residual tumors showed a decrease in Ki-67 positivity by at least 1%. The decrease of Ki-67 significantly correlated with better DFS (p = .001) and OS (P = .010) compared with no decrease, particularly in the luminal B-like and HER2-positive subgroups. The multivariate analysis showed that the decrease in Ki-67 level had a significant positive predictive value on DFS (HR = 0.47, 95% CI: 0.33-0.67; P.001) and OS (HR = 0.59, 95% CI: 0.36-0.82; P= .004) in all IBC patients.The decrease of Ki-67 expression after neoadjuvant chemotherapy has a prognostic significance in IBC patients with residual disease. Evaluation of Ki-67 changes may help to identify subgroups of patients with worse outcome to receive novel treatment in this setting.

The paper is devoted to investigating the quasi-synchronization issue of fractional-order multi-layer networks with mismatched parameters under delay-dependent impulsive feedback control. It is worth highlighting that fractional-order multi-layer networks with mismatched parameters, as the extension model for single-layer or two-layer ones, are constructed in this paper. Simultaneously, the intra-layer and inter-layer couplings are taken into consideration, which is more general and rarely considered in discussions of network synchronization. An extended fractional differential inequality with impulsive effects is given to establish the grounded framework and theory on the quasi-synchronization problem under delay-dependent impulsive feedback control. Moreover, in the light of the Lyapunov method and graph theory, two criteria for achieving the quasi-synchronization of fractional-order multi-layer networks with mismatched parameters are derived. Furthermore, exponential convergence rates as well as the bounds of quasi-synchronization errors are successfully deduced. Ultimately, the theoretical results are applied in a practical power system, and some illustrative examples are proposed to show the effectiveness of theoretical analysis.

Polyvinyl alcohol (PVA)/laponite (LP) nanocomposite coatings were fabricated via a facile one-step coassembly process. The formed nanocoatings contain a high concentration of LP nanosheets, which can be well aligned along the substrate surface during the coassembly process. Due to the highly orientated structure, the flexible nanocoatings exhibit ultra-high transparency and superior mechanical properties, and can also act as excellent gas barriers. Such nanocoatings can be exceptional candidates for a variety of applications, such as food packaging.

Overland flow resistance plays an important role in predicting hillslope hydrological and erosion processes on hillslopes. Soil surfaces covered with grass and/or gravel may increase hydraulic resistance to overland flow, but there is little information on the determination on these resistance components in a composite slopeland. In this study, the smooth and sand-bed surfaces covered with different gravel or/and grass (cover degree = 2.5%, 5%, 10%, 15%, 20%) under five slope gradients (3°, 6°, 9°, 12°, 15°) were subjected to inflows to investigate the hydraulic resistance and validate the sum law of resistance components. The results showed that, the overland flow mainly belonged to transition or turbulent and supercritical flow regime with 150

The first intermolecular electrophilic dearomatization of halonaphthols with benzyl/allyl bromides is described. Halonaphthols are used as carbon-nucleophiles in dearomatization to form three-dimensional cyclic enones with excellent chemoselectivity, in which etherification of phenolic hydroxyl group could be restrained well by using cesium carbonate as the base. A wide range of cyclic enones is directly prepared from various substituted benzyl/allyl bromides and halonaphthols. Mechanistic investigations suggest a direct SN2 reaction pathway.

Several studies have suggested that patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) might benefit from the use of tyrosine kinase inhibitors (TKIs) in combination with antiangiogenic agents. This study aimed to comprehensively review the available evidence regarding the efficacy and safety of first-line TKI plus antiangiogenic agents versus TKIs alone in EGFR-mutated advanced NSCLC.A literature search was performed using PubMed to identify studies published up to Feb. 2020. Abstracts from major international conferences reported over the last 5 years were searched. The primary outcome was progression-free survival (PFS), and the secondary outcomes included overall survival (OS), the objective response rate (ORR), and toxicity.In total, 7 relevant trials comprising 1612 patients were identified. TKIs plus antiangiogenic agents led to significant improvements in PFS regardless of the EGFR mutation subtype and presence of brain metastasis. In particular, in the subgroup with the L858R mutation, the hazard ratio (HR) of PFS was 0.58 (95% confidence interval [CI], 0.48-0.71, P.001). The OS following combined treatment was similar to that following TKI monotherapy. The ORR was increased with the use of TKIs plus antiangiogenic agents (HR 1.10, 95% CI, 1.01-1.20, P = .029). In the safety analyses, TKIs plus antiangiogenic agents exhibited a significantly increased incidence of adverse events of grade 3 or higher.The use of TKIs plus antiangiogenic agents is associated with significantly improved PFS and ORR compared with TKIs alone in untreated EGFR-mutated NSCLC. The toxicities of combination therapy should be considered when making treatment choices.

Gas-in-liquid foam templating is considered as a promising method for commercial-scale production of porous materials. However, Ostwald ripening occurs frequently during the preparation, which could bring about inhomogeneous bubbles with large sizes and deteriorate the performance of resultant products. To tackle this challenging task, we report a gelation network-triggered morphology-regulation strategy during the foaming process. As an exemplar, boehmite sol was incorporated into the andalusite suspension to stabilize the foam framework. After casting, the wet foam was able to maintain its overall shape, since andalusite particles were anchored onto the gas-liquid interface by the gelation network during mechanical frothing. The samples calcined at 1400°C feature homogeneous bubble with hierarchical porous architecture, smaller pore size with a mean value of 5.32 μm and robust compressive strength of 11.97MPa at a porosity level of 84 %. Our approach substantially broadens the design philosophy of high performance porous ceramics.

Structural design/doping strategy is an efficient method to prepare electrolytes with high oxygen ionic conductivity, but there is still hindrance for solid oxide fuel cell (SOFC) commercialization. Recent advances in semiconductor ionic materials have developed a novel strategy in designing low-temperature electrolyte materials. Here, a heterostructure composite of LSFC (La0.6Sr0.4Fe0.8Cu0.2O3-δ) and SDC (Sm0.2Ce0.8O2−δ) is developed. The LSFC-SDC composite exhibits a high ionic conductivity, >0.1S/cm at 550 °C. With symmetrical NCAL (Ni0.8Co0.15Al0.05LiO2-δ)-coated electrode, cells with SDC-LSFC electrolyte exhibit high open-circuit voltage (OCV), and achieve a significant power improvement (>1000 mW/cm2) compared with pure SDC electrolyte at 550 °C. The short-term stability result has proven the operating ability of SDC-LSFC electrolyte under fuel cell environment (H2/air). This work demonstrates a new developing route of low-temperature solid oxide fuel cell (LTSOFC), which is different from the conventional SOFC.

The silver nanowire (AgNWs) / cotton fiber was used as a conductive substrate with high conductivity charge transfer. Then the polyaniline (PANI) molecular chain was fixed on the AgNWs / cotton fiber by in-situ polymerization to prevent its dedoping and improve its cyclic properties. Thus the flexible capacitor electrode material with conductive, specific capacity and cyclic properties was obtained. The results showed that when the mass ratio of KH-560 to AgNWs/cotton fiber was 3:1, the grafting rate of epoxide group on the modified AgNWs/cotton fiber was the highest. When the mass ratio of aniline to modified AgNWs cotton fabric was 3:1, the PANI content of in-situ polymerization on the fabric surface was the highest, 20.83%. The specific capacity of PANI/AgNWs/cotton fiber electrode material was the highest, 154 F/g, after 5000 cycles of charging and discharging, the specific capacity could keep 96%. It is worth mentioning, the introduction of PANI and AgNWs could significantly improve the wear resistance of cotton fiber, the friction resistance of the cotton fabric increased to 36,000 times. It is provided a new idea for design a flexible capacitor electrode material integrating electrical conductivity and cyclic stability.

The traditional robust principal component analysis (RPCA) via decomposition into low-rank plus sparse matrices offers a powerful framework for a large variety of applications in computer vision. However, the reconstructed image experiences serious interference by Gaussian noise, resulting in the degradation of image quality during the denoising process. Thus, a novel manifold constrained joint sparse learning (MCJSL) via non-convex regularization approach is proposed in this paper. Morelly, the manifold constraint is adopted to preserve the local geometric structures and the non-convex joint sparsity is introduced to capture the global row-wise sparse structures. To solve MCJSL, an efficient optimization algorithm using the manifold alternating direction method of multipliers (MADMM) is designed with closed-form solutions and it achieves a fast and convergent procedure. Moreover, the convergence is analyzed mathematically and numerically. Comparisons among the proposed MCJSL and some state-of-the-art solvers, on several accessible datasets, are presented to demonstrate its superiority in image denoising and background subtraction. The results indicate the importance to incorporate the manifold learning and non-convex joint sparse regularization into a general RPCA framework.

Carbon nanodots (CDs) based fluorescent nanoprobes have recently drawn much attention in chemo-/bio-sensing and bioimaging. However, it is still challenging to integrate the colorimetric and fluorometric dual readouts into a single CD. Herein, novel hybrid CDs (HCDs) are prepared by a simple microwave-assisted reaction of citric acid (CA), branched polyethyleneimine (BPEI) and potassium thiocyanate (KSCN). As-prepared HCDs show extraordinary properties, including excitation-dependent emission, satisfactory fluorescence quantum yield (46.8%), excellent biocompatibility and optical stability. Significantly, the fluorescence intensity at 450 nm exhibits linear correlation over the Fe3+ concentration from 1 μmol/L to 150 μmol/L with a detection limit (LOD) of 52 nmol/L. Meanwhile, the solution color changes from colorless to orange, and the absorbance at 460 nm increased linearly with Fe3+ concentration ranging from 0.02 mmol/L to 5 mmol/L (LOD: 3.4 μmol/L). All the evidence illustrates that the HCDs can be conditioned for specific Fe3+ sensing with colorimetric and fluorometric dual readouts, which has also been verified with paper-based microchips. The possible mechanism is attributed to the specific interactions between surface functional groups on the HCDs and Fe3+. Additionally, the HCDs are successfully applied in sensing Fe3+ in wastewater and living cells, demonstrating its potential applications in future environment monitoring and disease diagnosis.