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Herein, a selective tandem C-C bond-forming reaction with CO2 was developed to realize the bridging of enaminones and synthesis of 1,4-dihydropyridines, respectively. n-Butylamine significantly promoted this CO2 deoxymethylenation procedure catalyzed by 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD) and ZnCl2. The mechanism involving the formation of bis(silyl)acetal, nucleophilic addition, and amine elimination was also interpreted to clarify the bridging of two molecules of enaminones with CO2 and the generation of dihydropyridine derivatives.

At present, cluster analysis has become a very good channel for analyzing gene expression data to obtain biological information. In recent years, many experts have used traditional clustering algorithms and new clustering algorithms to mine gene expression data. This article first introduces the preprocessing of gene expression data. Then, by using principal component analysis (PCA) to process the gene data, a small number of characteristic variables are extracted as new indicators, and the indicators are evaluated to achieve the purpose of dimensionality reduction. The dimension reduction index is applied to the dynamic self-organizing neural network (DSOM) neural network, and the victory neurons are selected by the minimum Euclidean distance. The characteristics of the genetic data are clustered through the DSOM network, and the gene types with similar characteristics are divided into one region. The results show that PCA and DSOM networks have a high accuracy rate for clustering of genetic data, and a clear division of boundaries.

A method based on the Okubo–Weiss parameter was used to detect subsurface eddies (SSEs) with an eddy-resolving ocean general circulation model. Statistical analyses showed that SSEs are ubiquitous in the northwestern Pacific Ocean. Three regions were found to have high probability of SSE, which are as follows: the latitudinal band between 9°N and 17°N, the Kuroshio extension region, and the area east of the Ryukyu Islands. Although surface eddies (SEs) were found distributed widely within the zonal band of the Subtropical Counter Current, few SSEs were found there. In contrast, few SEs were found to the east of The Philippines, whereas SSEs were abundant. The kinetic energy contained within SSE was found comparable in magnitude with that of SE. During 1993–2013, about 2569 and 2099 SSEs (at a depth of about 400 m) were observed to be anticyclonic and cyclonic, respectively; thus, SSEs tended to be anticyclonic. The mean radius, lifespan, and propagation speed of SSE in this study were about 60 km, 50 days, and 6.6 cm/s, respectively. The propagation speed showed a wave-like decrease with increasing latitude. Some long-lived SSEs were found to persist for longer than 4 months and to move thousands of kilometers. About 89% of SSEs were nonlinear for at least half their lifespan, which implies that SSE can trap interior fluid during translation. Trajectories revealed that SSEs propagate nearly due west with only small meridional deflection. The findings of this study will contribute to the enrichment of our knowledge regarding SSE in the northwestern Pacific Ocean.

Unsupervised clustering aims at discovering the semantic categories of data according to some distance measured in the representation space. However, different categories often overlap with each other in the representation space at the beginning of the learning process, which poses a significant challenge for distance-based clustering in achieving good separation between different categories. To this end, we propose Supporting Clustering with Contrastive Learning (SCCL) -- a novel framework to leverage contrastive learning to promote better separation. We assess the performance of SCCL on short text clustering and show that SCCL significantly advances the state-of-the-art results on most benchmark datasets with 3%-11% improvement on Accuracy and 4%-15% improvement on Normalized Mutual Information. Furthermore, our quantitative analysis demonstrates the effectiveness of SCCL in leveraging the strengths of both bottom-up instance discrimination and top-down clustering to achieve better intra-cluster and inter-cluster distances when evaluated with the ground truth cluster labels., Comment: NAACL 2021

Unsupervised domain adaptation addresses the problem of leveraging labeled data in a source domain to learn a well-performing model in a target domain where labels are unavailable. In this paper, we improve upon a recent theoretical work (Zhang et al., 2019b) and adopt the Margin Disparity Discrepancy (MDD) unsupervised domain adaptation algorithm to solve the cross-lingual text labeling problems. Experiments on cross-lingual document classification and NER demonstrate the proposed domain adaptation approach advances the state-of-the-art results by a large margin. Specifically, we improve MDD by efficiently optimizing the margin loss on the source domain via Virtual Adversarial Training (VAT). This bridges the gap between theory and the loss function used in the original work Zhang et al.(2019b), and thereby significantly boosts the performance. Our numerical results also indicate that VAT can remarkably improve the generalization performance of both domains for various domain adaptation approaches.

We propose an end-to-end approach for synthetic QA data generation. Our model comprises a single transformer-based encoder-decoder network that is trained end-to-end to generate both answers and questions. In a nutshell, we feed a passage to the encoder and ask the decoder to generate a question and an answer token-by-token. The likelihood produced in the generation process is used as a filtering score, which avoids the need for a separate filtering model. Our generator is trained by fine-tuning a pretrained LM using maximum likelihood estimation. The experimental results indicate significant improvements in the domain adaptation of QA models outperforming current state-of-the-art methods., Comment: EMNLP 2020

This work aims to develop an adaptive nonlinear elimination preconditioned inexact Newton method as the numerical solution of large sparse multi-component partial differential equation systems with highly local nonlinearity. A nonlinear elimination algorithm used as a nonlinear preconditioner has been shown to be a practical technique for enhancing the robustness and improving the efficiency of an inexact Newton method for some challenging problems, such as the transonic full potential problems. The basic idea of our method is to remove some components causing troubles in order to decrease the impact of local nonlinearity on the global system. The two key elements of the method are the valid identification of the to-be-eliminated components and the choice of subspace correction systems, respectively. In the method, we employ the point-wise residual component of nonlinear systems as an indicator for selecting these to-be-eliminated components adaptively and build a subspace nonlinear system consisting of the components corresponding to the bad region and an auxiliary linearized subsystem to reduce the interfacial jump pollution. The numerical results demonstrate that the new approach significantly improves performance for incompressible fluid flow and heat transfer problems with highly local nonlinearity when compared to the classical inexact Newton method.

Two-dimensional (2D) ordered micro/nanostructured arrays have attracted intense interest for potential applications in a wide variety of fields, such as surface-enhanced Raman scattering, chemical and biological sensing, catalysis, energy storage, and conversion. In this paper, MoS2/TiO2 nanohole arrays are prepared by combing colloidal lithography and dip-coating method. The decorating of MoS2 nanosheets can significantly improve the photoelectrochemical and photocatalytic activity of TiO2 nanohole arrays in the visible light region. The photocurrent density of the optimized MoS2/TiO2 sample is 17.8 times higher than that of the pristine TiO2 film, while the enhancement factor of the corresponding kinetic constant in photocatalytic degradation is about 5.2. Our first-principles calculation results are in good agreement with the experimental observations. On the basis of the experimental and theoretical results, such enhanced performances can be assigned to two reasons: one is the improved visible light h...

We develop and study a framework of multiscale finite element method (MsFEM) for solving the elliptic interface problems. Finding an appropriate boundary condition setting for local multiscale basis function problems is the current topic in the MsFEM research. In the proposed framework, which we call the iteratively adaptive MsFEM (i-ApMsFEM), the local-global information exchanges through iteratively updating the local boundary condition. Once the multiscale solution is recovered from the solution of global numerical formulation on coarse grids, which couples these multiscale basis functions, it provides feedback for updating the local boundary conditions on each coarse element. The key step of i-ApMsFEM is to perform a few smoothing iterations for the multiscale solution to eliminate the high-frequency error introduced by the inaccurate coarse solution before it is used for setting the boundary condition. As the method iterates, the quality of the MsFEM solution improves, since these adaptive basis functions are expected to capture the multiscale feature of the approximate solution more accurately. We demonstrate the advantage of the proposed method through some numerical examples for elliptic interface benchmark problems.

Ti3C2 MXene-based composites are emerging two-dimensional (2D) layered materials promising in electrochemical energy storage devices such as rechargeable ion batteries and supercapacitors. However, scalable preparation of Ti3C2 MXene-based composites, especially, integrated with one-dimensional (1D) materials through a facile low-temperature strategy remains a considerable challenge. Herein, novel sandwich-like Na0.23TiO2/Ti3C2 composites made of 1D amorphous Na0.23TiO2 nanobelts growing on 2D Ti3C2 nanosheets have been prepared through a one-step scalable transformation reaction of Ti3C2 MXene. The sandwich-like Na0.23TiO2/Ti3C2 composites comprising of 1D ultrathin nanobelts, 2D conductive nanosheets and 3D sandwich-like architecture with electrically connecting interfaces inside can effectively relieve strain of the electrode upon cycling, facilitate carrier transport dynamics and protect aggregation of the electrode material, favorable for high-performance rechargeable batteries. As a result, when employed as anodes in Li/Na-ion batteries, the Na0.23TiO2/Ti3C2 electrodes exhibit superior long cycling stability (up to 4000 cycles at the high rates with respective capacity retention of over or nearly 100%), and remarkable rate capability. This work may open a new way for scalable synthesis of 2D layered MXene-based composites with desired architectures and properties for practical energy applications.

With the development and penetration of information technology, the “fourth media”-the network media is coming, and the “grievance crisis” is increasingly happening. The effective monitoring of online public opinion information becomes a problem. For each university, how to understand the sensation of teachers and students in real time in the era of informationization entering the intelligent campus has become an urgent problem for all colleges and universities. This paper first analyzes the characteristics of Weibo’s communication and the process of microblogging’s public opinion formation, the mechanism of communication, and so on. For the acquisition of this information, the reptile method was used to obtain the required data, which was beneficial to the real-time sensation in the smart campus. Then, based on the improved single-pass algorithm to analyze the new characteristics of microblog propagation information and the public opinion sent by college students, and compared the improved single-pass algorithm with the effect of single-pass algorithm, the improved algorithm had the recall rate was high, the false detection rate was low, and the running time was short. Finally, taking the lyrics of college teachers and students as the research object, unified modeling language modeling was used to analyze the public opinion monitoring platform of the smart campus, and the campus public opinion of several major events was monitored and analyzed. This provided a reference for the effective, intelligent, and real-time detection of Weibo public opinion in colleges and universities.

The Kerama Gap is an important passage for water exchange between the East China Sea (ECS) and the northwestern Pacific (NP). The mean Kerama Gap transport (KGT) is small into the ECS (~ 2.0 Sv) but with a large standard deviation (~ 4.5 Sv), which has a significant influence on the variation of Kuroshio transport. The effects of mesoscale eddies on the variation of KGT are investigated by using a 25-year Pacific Hybrid Coordinate Ocean Model from 1979 to 2003. Model results show that the variation of KGT is mainly determined by the variation of sea level difference between the northeast and southwest of the Kerama Gap, and these differences are dominated by the westward propagating mesoscale eddies. The effects of mesoscale eddies depend on the meridional location of these eddies. When the anticyclonic (cyclonic) eddy is located in the northeast of the Kerama Gap or the cyclonic (anticyclonic) eddy is located in the southwest of the Kerama Gap, the KGT shows a strong positive (negative) anomaly. However, when the eddy is located in the central region of the Kerama Gap, the KGT shows a relatively smaller anomaly. Besides, the variation of Kuroshio, strongly influenced by the eddies east of Taiwan, also plays an important role in influencing the variation of KGT. When the Kuroshio transport crossing the upstream section of the Kerama Gap is high (low) or the Kuroshio central position shifts to (away from) the Kerama Gap there will be more (less) water flow from the ECS to the NP.

The preparation method of nano-scaled polymeric materials was described in this work. Nano-scaled novel composites of elastomeric ter-polypropylene blended with isotactic polypropylene (iPP) were investigated. The composites were synthesized by zirconium complex/methylaluminoxane(MAO) catalyst system through in-situ polymerization. This novel materials consisted of different lengths of crystallizable iPP segments and rubbery amorphous blocks that polymerized by 1-octene, propylene and ethylene in varying proportions. The mechanical properties of the composites were desired that the iPP segments contributed to the strength and the rubbery amorphous blocks contributed to the flexibility. The result showed that the composites can be used as a kind of elastomer.

Mesoscale eddies play an essential role in transporting energy and modulating the spatial and temporal distribution of turbulent mixing. By analyzing the microstructure and hydrographic observation data in the subtropical Northwestern Pacific Ocean (STNWP), we found that the turbulent kinetic energy (TKE) dissipation rate influenced by an anticyclonic eddy (AE) in the thermocline was enhanced by at least 3–6 times over the background dissipation level. Most turbulent dissipation is driven by the break of internal wave. The AE effect as the reason for the increasing strength of internal wave energy below the mixed layer indicated a linkage between turbulent dissipation and AE. After discussing the gradient Richardson number, we found that only when the two factors of large internal wave energy and shear instability occurred together could the dissipation rate be enhanced, ultimately promoting turbulent mixing. Moreover, the internal wave field was found to have a higher inertial frequency in the regions influenced by AE than in the background regions where the frequency of the internal wave was dominated mainly by the near-inertial frequency. Therefore, AE can introduce an important, new spatial distribution of internal wave energy, which has a potential influence on turbulent mixing.

Many scientific and engineering applications require accurate, fast, robust, and scalable numerical solution of large sparse algebraic polynomial eigenvalue problems (PEVP’s) that arise from some appropriate discretization of partial differential equations. The polynomial Jacobi-Davidson (PJD) algorithm has been numerically shown as a promising approach for the PEVP’s to finding the interior spectrum. The PJD algorithm is a subspace method, which extracts the candidate eigenpair from a search space and the space updated by embedding the solution of the correction equation at the JD iteration. In this research, we develop and study the two-level PJD algorithm for PEVP’s with emphasis on the application of the dissipative acoustic cubic eigenvalue problem. The proposed two-level PJD algorithm consists of two important ingredients: A good initial basis for the search space is constructed on the fine-level by using the interpolation of the coarse solution of the same eigenvalue problem in order to enhance the robustness of the algorithm. Also, an efficient and scalable two-level preconditioner based on the Schwarz framework is used for the correction equation. Some numerical examples obtained on a parallel cluster of computers are given in order to demonstrate the robustness and scalability of our PJD algorithm.

We propose an iteratively adaptive Multi-scale Finite Element Method (MsFEM) for elliptic PDEs with rough coefficients. The choice of the local boundary conditions for the multi-sale basis functions determines the accuracy of the MsFEM numerical solution, and one needs to incorporate the global information of the elliptic equation into the local boundary conditions of the multi-scale basis functions to recover the underlying fine-mesh solution of the equation. In our proposed iteratively adaptive method, we achieve this global-to-local information transfer through the combination of coarse-mesh solving using adaptive multi-scale basis functions and fine-mesh smoothing operations. In each iteration step, we first update the multi-scale basis functions based on the approximate numerical solutions of the previous iteration steps, and obtain the coarse-mesh approximate solution using a Galerkin projection. Then we apply several steps of smoothing operations to the coarse-mesh approximate solution on the underlying fine mesh to get the updated approximate numerical solution. The proposed algorithm can be viewed as a nonlinear two-level multi-grid method with the restriction and prolongation operators adapted to the approximate numerical solutions of the previous iteration steps. Convergence analysis of the proposed algorithm is carried out under the framework of two-level multi-grid method, and the harmonic coordinates are employed to establish the approximation property of the adaptive multi-scale basis functions. We demonstrate the efficiency of our proposed multi-scale methods through several numerical examples including a multi-scale coefficient problem, a high-contrast interface problem, and a convection-dominated diffusion problem.

Variations in water exchange through the Kerama Gap (between Okinawa Island and Miyakojima Island) from 1979 to 2003 were estimated with the 0.08° Pacific HYbrid Coordinate Ocean Model (HYCOM). The model results show that the mean transport through the Kerama Gap (KGT) from the Pacific Ocean to the East China Sea (ECS) was 2.1 Sv, which agrees well with the observed mean KGT (2.0 Sv) for 2009–2010. Over the time period examined, the monthly KGT varied from -10.9 Sv to 15.8 Sv and had a standard deviation of ± 5.0 Sv. The water mainly enters the ECS via the subsurface layer (300–500 m) along the northeastern slope of the Kerama Gap and mainly flows out of the ECS into the southwest of the Kerama Gap. The seasonal and interannual variations of the KGT and the Kuroshio upstream transport were negatively correlated. The Kuroshio upstream transport was largest in summer and smallest in autumn while the KGT was smallest in summer (1.02 Sv) and largest in spring (2.94 Sv) and autumn (2.44 Sv). The seasonal and interannual variations in the Kuroshio downstream (across the PN-line) transport differed significantly from the Kuroshio upstream transport but corresponded well with the KGT and the sum of the transport through the Kerama Gap and the Kuroshio upstream, which indicates that information about variation in the KGT is important for determining variation in the Kuroshio transport along the PN-line.

Polyolefins with polar groups exhibited many applications as high-performance materials have been the subject of considerable research. In this study, terpolymers of ω-bromo-α-olefins with ethylene and propylene were synthesized in the presence of three multi-chelated non-metallocene titanium complexes. The structure and properties of the terpolymers were determined by 1H NMR, 13C NMR, Fourier transform infrared, differential scanning calorimetry after treatment by successive self-nucleating and annealing and wide-angle X-ray diffractograms. Furthermore, the stress–strain behaviors of the terpolymers were measured with ASTMD1708 microtensile, and the specimens were from the obtained terpolymer films. The results indicated that these catalysts were efficient for the terpolymerization. The catalytic activity was as high as 6.21 × 105 gP (molTi)−1 h−1 for terpolymerization of 11-bromo-1-undecylene with ethylene and propylene. The insertion ratio of 11-bromo-1-undecylene was up to 2.49 mol% confirmed by 1H NMR and 13C NMR. As for the terpolymers, their melting points decreased and their plasticity became weak with the incorporation of ω-bromo-α-olefins increasing. GPC results showed that the terpolymers had high weight-average molecular weight up to 2.51 × 105 g mol−1. Molecular weight distribution of the terpolymers was about 2, implying single-site mechanism for the terpolymerization, but slightly broader than that of ethylene/propylene copolymer.

Ocean salinity is often used as a dynamical tracer for investigating the Kuroshio intrusion into the South China Sea (SCS). In this study, we found that the upper-ocean water in the SCS had a freshening trend since the early 1990s. Salinity in the upper 100 m of the SCS ( S SCS ) decreased by ~0.24 psu in the period 1993–2012, yielding a negative trend of −0.012 psu yr −1 . The maximum freshening occurred in the surface layer west of the Luzon Strait, and freshening gradually lessened from northeast to southwest and with depth, indicating the important influence of the Kuroshio intrusion. Quantitative analysis of salinity budget from the surface to 100 m depth in the SCS suggests that the weakened Kuroshio intrusion is the leading factor controlling the S SCS freshening, while the increased air-sea freshwater flux plays a minor role. Based on GODAS (Global Ocean Data Assimilation System) model output, the Luzon Strait transport (LST) in the upper 100 m decreased in a negative trend of −0.12 Sv yr −1 (1 Sv=10 6 m 3 s −1 ) from 1993 to 2012, corresponding to a freshening trend of the S SCS at a rate of −0.011 psu yr −1 . Both the LST and S SCS changes are closely related to the Pacific Decadal Oscillation (PDO). Our findings demonstrate that the strength of the Kuroshio intrusion into the SCS weakened markedly since the PDO phase shifted in 1990s, which resulted in the pronounced freshening of the SCS water.

We propose a novel neural topic model in the Wasserstein autoencoders (WAE) framework. Unlike existing variational autoencoder based models, we directly enforce Dirichlet prior on the latent document-topic vectors. We exploit the structure of the latent space and apply a suitable kernel in minimizing the Maximum Mean Discrepancy (MMD) to perform distribution matching. We discover that MMD performs much better than the Generative Adversarial Network (GAN) in matching high dimensional Dirichlet distribution. We further discover that incorporating randomness in the encoder output during training leads to significantly more coherent topics. To measure the diversity of the produced topics, we propose a simple topic uniqueness metric. Together with the widely used coherence measure NPMI, we offer a more wholistic evaluation of topic quality. Experiments on several real datasets show that our model produces significantly better topics than existing topic models., In Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics (pp. 6345-6381)

We consider a quintic polynomial eigenvalue problem arising from the finite volume discretization of a quantum dot simulation problem. The problem is solved by the Jacobi–Davidson (JD) algorithm. Our focus is on how to achieve the quadratic convergence of JD in a way that is not only efficient but also scalable when the number of processor cores is large. For this purpose, we develop a projected two-level Schwarz preconditioned JD algorithm that exploits multilevel domain decomposition techniques. The pyramidal quantum dot calculation is carefully studied to illustrate the efficiency of the proposed method. Numerical experiments confirm that the proposed method has a good scalability for problems with hundreds of millions of unknowns on a parallel computer with more than 10,000 processor cores.

Non-metallocene catalysts containing [N, Si, N, P]-type ligands based on diphenyl phosphorus-phenylamine and their derivatives were synthesized and characterized by H(13C) NMR, ESI–MS and micro analysis. They were able to catalyze copolymerization of ethylene with N-acetyl-O-(hex-5-enyl)-l-tyrosine ethyl ester after activated by methylaluminoxane (MAO). Effects of transition metal atoms (Ti, Zr and Hf), ligand structures and polymerization conditions were investigated. The structures and properties of the obtained polymers were characterized by FT-IR, 13C NMR, GPC and DSC. The results indicated that the obtained copolymers had high weight average molecular weight of 2.70 × 105 g/mol and high comonomer incorporation rate of 23.07 wt% within the copolymer chain. The melting temperature of the copolymer was up to 138.6 °C higher than that of the polyethylene.

The full-space Lagrange--Newton algorithm is one of the numerical algorithms for solving problems arising from optimization problems constrained by nonlinear partial differential equations. Newton-type methods enjoy fast convergence when the nonlinearity in the system is well-balanced; however, for some problems, such as the control of incompressible flows, even linear convergence is difficult to achieve and a long stagnation period often appears in the iteration history. In this work, we introduce a nonlinearly preconditioned inexact Newton algorithm for the boundary control of incompressible flows. The system has nine field variables, and each field variable plays a different role in the nonlinearity of the system. The nonlinear preconditioner approximately removes some of the field variables, and as a result, the nonlinearity is balanced and inexact Newton converges much faster when compared to the unpreconditioned inexact Newton method or its two-grid version. Some numerical results are presented to d...

A nonlinear multigrid solver for solutions of unsteady three-dimensional incompressible viscous flow working on multi-GPU cluster is developed. The solver consists of a full approximation scheme (FAS) V-cycle scheme to accelerate the computation, in which the artificial compressibility method based Navier-Stokes solver is used as a smoother. Multi-stream overlapping strategies are designed to assist multi-GPU computations. The numerical procedure is validated by computing 3D laminar and turbulent flows within a lid-driven cubic cavity. The predicted results compare favorably with previous benchmark solutions and measurements, both in mean and turbulent quantities. For the performance of the FAS V-cycle scheme, up to two orders of magnitude speedups are reported, and the relationship between work unit (WU) and total grid number N is O ( N 0.3 ) under the deepest FAS V-cycle. A detailed evaluation of the GPU implementation is carried out employing the Roofline model and the scalability analysis.

This work was conducted to study the effect of soil pH (4.0, 6.0, and 8.0) on the transport, fractionation, and oxidation of trivalent chromium [Cr(III)]. Variation in pH altered soil chemical and mineralogical properties such as zeta potential, cation exchange capacity and redox potential of natural soil. Breakthrough curves and batch sorption experiments coupled with fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analyses demonstrated that the easy mobility of Cr(III) in pH 4.0 soil was dominated by the limited coordination effect. The high retention of Cr(III) in pH 8.0 soil was mainly ascribed to the hydrolysis. Incubation experiments indicated that the proportions of Cr in exchangeable fraction decreased with increasing of soil pH and incubation time, and kinetics analysis revealed that the time dependent transformation was controlled by mass transfer and chemical processes (e.g., hydrolysis, ion association). The XPS confirmed the oxidation of Cr(III) in pH 8.0 soil during the incubation period. Furthermore, the content of toxic hexavalent chromium [Cr(VI)] was positively associated with time and initial concentration of Cr(III) released. These results revealed the hazardousness of Cr(III) in soil contaminated simultaneously by inorganic acid and alkali.

Due to the technical advantages and performance enhancement of Long Term Evolution (LTE), LTE for railway system is a promising evolutional train to ground communication system instead of the Global System for Mobile Communications-Railway (GSM-R) in High-Speed Railway (HSR). To mitigate the effects of inter-cell interference of LTE-R on the QoS of HSR communication applications, the fractional frequency reuse (FFR) and soft frequency reuse (SFR) schemes are designed in the linear radio coverage scenario. Based on the moment generating function (MGF) approach, a novel theoretical analysis method of area spectral efficiency (ASE) in uplink and downlink for both FFR and SFR schemes is presented. We also investigate the impacts of overlapping depth between the adjacent cells on the system performance of LTE-R. The simulation results show that the reasonable frequency reuse techniques can be selected in accordance with different overlapping depths to improve the performance of LTE-R.

The TCP family genes are plant-specific transcription factors and play important roles in plant development. TCPs have been evolutionarily and functionally studied in several plants. Although common wheat (Triticum aestivum L.) is a major staple crop worldwide, no systematic analysis of TCPs in this important crop has been conducted. Here, we performed a genome-wide survey in wheat and found 66 TCP genes that belonged to 22 homoeologous groups. We then mapped these genes on wheat chromosomes and found that several TCP genes were duplicated in wheat including the ortholog of the maize TEOSINTE BRANCHED 1. Expression study using both RT-PCR and in situ hybridization assay showed that most wheat TCP genes were expressed throughout development of young spike and immature seed. Cis-acting element survey along promoter regions suggests that subfunctionalization may have occurred for homoeologous genes. Moreover, protein–protein interaction experiments of three TCP proteins showed that they can form either homodimers or heterodimers. Finally, we characterized two TaTCP9 mutants from tetraploid wheat. Each of these two mutant lines contained a premature stop codon in the A subgenome homoeolog that was dominantly expressed over the B subgenome homoeolog. We observed that mutation caused increased spike and grain lengths. Together, our analysis of the wheat TCP gene family provides a start point for further functional study of these important transcription factors in wheat.

The dispersion of graphene-based materials in lubricating oil is a prerequisite for improving its friction and wear performance. In this study, polyhedral oligomeric silsesquioxane (POSS) grafted graphene oxide (GO) was synthesized with an aim to improve the dispersibility of graphene in synthetic base oil. The composition and morphology of POSS-GO conjugates were characterized by FTIR, XPS, Raman spectroscopy, TEM and SPM. The tribological behavior of base oil with various concentrations of POSS-GO were examined using a UMT-3 friction and wear tester, and the worn surfaces were analyzed using Raman spectroscopy. It was found that concentrations of POSS-GO additives in the base oil is an important aspect for decreasing the friction and wear of the lubricated solid contacts. At lower and higher concentrations of POSS-GO, the lubricating effect is not effective or even worse. In contrast, at optimized concentration of POSS-GO, graphene sheets could form a boundary tribofilm between the contact, resulting in reduction of the friction coefficient and wear.

We propose a novel stochastic global optimization algorithm with applications to the refinement stage of protein docking prediction methods. Our approach can process conformations sampled from multiple clusters, each roughly corresponding to a different binding energy funnel. These clusters are obtained using a density-based clustering method. In each cluster, we identify a smooth “permissive” subspace which avoids high-energy barriers and then underestimate the binding energy function using general convex polynomials in this subspace. We use the underestimator to bias sampling towards its global minimum. Sampling and subspace underestimation are repeated several times and the conformations sampled at the last iteration form a refined ensemble. We report computational results on a comprehensive benchmark of 224 protein complexes, establishing that our refined ensemble significantly improves the quality of the conformations of the original set given to the algorithm. We also devise a method to enhance the ensemble from which near-native models are selected.

An extra-large subsurface anticyclonic eddy (SAE) with horizontal scale of 470 km was detected in the northwestern Pacific subtropical gyre by in situ measurements in October 2014. The SAE exhibited a lens-shaped vertical structure with shoaling of the seasonal thermocline and deepening of the main thermocline. Consequently, the water in the eddy core was colder above 200 m and warmer below 200 m than the surrounding waters with maximum temperature anomalies of -1.2°C and 3.5°C located at ~100 m and ~450 m depths, respectively. The central water mass of the SAE was characterized as low potential vorticity water, i.e., the north Pacific Subtropical Mode Water (STMW). Swirl velocity of the SAE was directly observed by ship-mounted ADCP (Acoustic Doppler Current Profilers). The maximum azimuthal velocity reached 0.35 ms-1 near a 110 km radius at ~ 200 m depth, which was comparable with the maximum velocity of the northward Kuroshio east of Taiwan at the same depth. Threedimensional structure and evolutionary process of the SAE were also presented using Argo float profile data as well as the satellite altimeter data. The results indicated that the SAE was generated in the region of the STMW in February, then propagated westward over 1500 km at a mean speed of ~0.06 ms-1 and finally disappeared east of Taiwan in December, transporting ~0.5 Sv (Sv=106 m3s-1) STMW.

This paper focuses on sparse Volterra filter in high power budget IMDD OFDM-PON. The simulation results show that the power budget @ 50Gbps is up to 32dB with low complexity equalizer in ONU receivers. The experimental results show that this scheme could achieve 20 Gbps transmission over 95-km SMF.

Three typhoon events were selected to examine the impact of energy transformation on near-inertial oscillations (NIOs) using observations from a subsurface mooring, which was deployed at 125&deg, E and 18&deg, N on 26 September 2014 and recovered on 11 January 2016. Almost 16 months of continuous observations were undertaken, and three energetic NIO events were recorded, all generated by passing typhoons. The peak frequencies of these NIOs, 0.91 times of the local inertial frequency f, were all lower than the local inertial frequency f. The estimated vertical group velocities (Cgz) of the three NIO events were 11.9, 7.4, and 23.0 m d&minus, 1, and were relatively small compared with observations from other oceans (i.e., 100 m d&minus, 1). The directions of the horizontal near-inertial currents changed four or five times between the depths of 40 and 800 m in all three NIO events, implying that typhoons in the northwest Pacific usually generate high-mode NIOs. The NIO currents were further decomposed by performing an empirical orthogonal function (EOF) analysis. The first and second EOF modes dominated the NIOs during each typhoon, accounting for more than 50% of the total variance. The peak frequencies of the first two EOF modes were less than f, but those of the third and fourth modes were higher than f. The frequencies of all the modes during non-typhoon periods were more than f. Our analysis indicates that the relatively small downward group velocity was caused by the frequent direction changes of the near-inertial currents with depth.

Two novel cycloalkoxy silane compounds (ED1 and ED2) were synthesized and used as the external electron donors (EEDs) in Ziegler–Natta catalysts with diethyl 2,3-diisopropylsuccinate as internal electron donor. The results indicated that the Ziegler–Natta catalysts using ED1 and ED2 as EEDs had high catalytic activities and good stereoselectivities. The melt flow rate (MFR) and gel permeation chromatography (GPC) results revealed that the obtained polypropylene has higher MFR and lower average molecular weights than the commercial EED cyclohexyl methyl dimethoxysilane. The differential scanning calorimetry (DSC) results indicated that new isospecific active centers formed after the introduction of new external donors. The work implied that the novel EEDs could improve the hydrogen sensitivities of the catalyst system and obtain polymers with high melt flow rate.

Soil chemical and topographic properties are two important factors influencing available micronutrient distribution of soil in the horizontal dimension. The objective of this study was to explore the relative influence of soil chemistry (including soil pH, soil organic matter, total nitrogen, available phosphorus, and available potassium) and topography (including elevation, slope, aspect, and wetness index) on the availability of micronutrients (Fe, Mn, Cu, Zn, and B) using structural equation modeling (SEM) at the watershed scale. To do this, levels of soil micronutrients, pH, soil organic matter, total nitrogen, available phosphorus, available potassium, and topographic factors were measured at 523 sampling points of Fanshi County on the Chinese Loess Plateau, and the spatial distribution of soil available micronutrients were analyzed by geostatistical method. The results showed that topography had both direct effects and indirect effect on some soil micronutrients, while the indirect effect indicated effects from topography on soil chemistry and then further on micronutrient concentration. Soil chemistry had direct effects on levels of all soil micronutrients, and topography had direct effects on levels of all micronutrients except for Cu and B, and indirect effects on Fe, Zn, and B. The direct effect of soil chemistry on Fe levels was greater than the total effects (including both direct and indirect) of topography. Topography had a stronger direct effect on Mn than soil chemistry, and topography had less direct but stronger total effects on Zn than soil chemistry. Soil chemistry directly influenced both Cu and B, but topography only influenced B in an indirect manner. The semivariance indicated that the micronutrients had moderate spatial dependency except for B which had weak spatial dependency. Within the spatial distribution of the micronutrients, there was a zone in the middle of the watershed with lower values than in the northern and southern areas for Fe, Mn, Zn, and B, which were related to the characteristics of topography and soil chemistry. These results may guide the management of soil micronutrients of the Chinese Loess Plateau and other similar regions in the world.

Dispersion of graphene nanosheets in a water and polymer matrix has been rarely achieved due to graphene's hydrophobicity, which thus impedes its potential anticorrosive application. In this study, stable graphene aqueous dispersion was obtained by using imidazole-based polymeric ionic liquid (PIL) as the dispersant with ultrasonic vibration. Stacked graphene sheets were exfoliated to a few layers via cation-π interaction between PIL and graphene nanosheets. Electrochemical impedance measurements were taken to investigate the anticorrosion performance of epoxy coatings with or without polymeric ionic liquid–graphene (PIL–G) hybrids. Results indicated that the PIL–G hybrid significantly enhanced the long-term protective performance of epoxy coatings, which was attributed to the synergistic effects of the corrosion-inhibitive PIL and impermeable graphene nanosheets.

Bismuth vanadate (BiVO4) has been considered as one of the promising Photoelectrochemical (PEC) photoanode materials. However, the performances remain poorly rated due to inefficient carrier separation, short carrier diffusion length, and sluggish water oxidation kinetics. Herein, a photoanode consisting of MoS2 nanosheet coating on the three-dimensional ordered BiVO4 inverse opal is fabricated by a facile combination of nanosphere lithography and hydrothermal methods. By taking advantage of the photonic crystal and two-dimensional material, the optimized MoS2/BiVO4 inverse opal photoanode exhibits a 560% improvement of the photocurrent density and threefold enhancement of the incident photon-to-current efficiency than that of the pristine BiVO4 film photoanode. Systematic studies reveal that the excellent PEC activity should be attributed to enhanced light harvesting and charge separation efficiency.

BiFeO3 (BFO)-based ferroelectrics have been proved to be visible-light-driven photoelectrodes for O2 production. However, the hitherto reported photoelectrochemical performances remain inferior to meet the requirements for any applications. Besides, expensive noble metals (Ag, Au) are commonly required to achieve high photoelectric conversion efficiency. Here, the significant enhancements of photoelectrochemical performance is reported by fabricating a noble-metal-free reduced graphene oxide (RGO)/BFO composite film via a simple and cost-effective solution process. The optimized RGO/BFO composite film exhibits a 600% improvement of the short-circuit photocurrent density compared to that of the pristine BFO, and also outperforms the noble-metal/BFO cells under the same reaction conditions. Furthermore, the incident photon-to-current efficiency of the optimized RGO/BFO sample shows threefold enhancement. This study delivers a facile and low-cost approach to preparing 2D materials/ferroelectric heterostructures and offers a promising pathway to boost the performance of semiconducting ferroelectric photoelectrodes.

The present study aimed to investigate the pharmacokinetic properties of febuxostat in healthy Chinese male volunteers and evaluate whether the two formulations of febuxostat 40-mg and 80-mg tablets are bioequivalent. A randomized, open-label, 4-way crossover study was conducted in healthy Chinese male volunteers under fasting conditions. 24 eligible subjects were randomized in a 1:1:1:1 ratio to receive a single dose of test or reference formulation of febuxostat 40-mg or 80-mg tablet. The washout period between each administration was 1 week. Plasma febuxostat was quantified by a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Tolerability was evaluated by monitoring adverse events, physical examinations, 12-lead ECG and laboratory tests. After single-dosing of 1 tablet of 40-mg febuxostat, the pharmacokinetic parameters of test and reference formulations were: Tmax 1.22±0.87 and 1.85±1.03 h, Cmax 1689.16±461.31 and 1613.80±608.43 ng·mL-1, AUC0-t 5139.87±1349.28 and 5517.91±2024.26 ng·mL-1·h, AUC0−∞ 5263.06±1339.16 and 5640.48±2040.22 ng·mL-1·h, t1/2 4.82±2.61 and 4.85±1.78 h, respectively. After single-dosing of 1 tablet of 80-mg febuxostat, the pharmacokinetic parameters of test and reference formulations were: Tmax 1.71±1.21 and 2.23±1.55 h, Cmax 2744.47±1157.44 and 2998.17±1200.13 ng·mL-1, AUC0-t 9634.03±2768.25 and 10467.95±3501.65 ng·mL-1·h, AUC0−∞ 9834.32±2730.51 and 10626.63±3504.08 ng·mL-1·h, t1/2 6.25±2.44 and 5.46±1.65 h, respectively. For single-dosing of 1 tablet of 40-mg febuxostat, 90% CIs for the test/reference ratio of AUC0-t, AUC0−∞ and Cmax were 89.79 to 102.55, 90.14 to 102.56 and 93.99 to 129.63, respectively. For single-dosing of 1 tablet of 80-mg febuxostat, 90% CIs for the test/reference ratio of AUC0-t, AUC0−∞ and Cmax were 86.67 to 100.00, 87.50 to 100.51 and 79.48 to 105.99, respectively. This single dose study revealed similar pharmacokinetic properties in healthy Chinese male volunteers as those found in Caucasic population. The test and reference febuxostat tablets formulations met the regulatory criteria for bioequivalence at 40-mg and 80-mg strengths in fasting healthy Chinese male volunteers. Trial Registration: Chictr.org ChiCTR-TTRCC-14004288

BiVO4 photonic crystal inverse opals (io-BiVO4) with highly dispersed Ag nanoparticles (NPs) were prepared by the nanosphere lithography method combining the pulsed current deposition method. The incorporation of the Ag NPs can significantly improve the photoelectrochemical and photocatalytic activity of BiVO4 inverse opals in the visible light region. The photocurrent density of the Ag/io-BiVO4 sample is 4.7 times higher than that of the disordered sample without the Ag NPs, while the enhancement factor of the corresponding kinetic constant in photocatalytic experiment is approximately 3. The improved photoelectrochemical and photocatalytic activity is benefited from two reasons: one is the enhanced light harvesting owing to the coupling between the slow light and localized surface plasmon resonance effect; the other is the efficient separation of charge carriers due to the Schottky barriers.