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The risk of cholangitis after ERCP implantation in malignant obstructive jaundice patients remains unknown. To develop models based on artificial intelligence methods to predict cholangitis risk more accurately, according to patients after stent implantation in patients' MOJ clinical data. This retrospective study included 218 patients with MOJ undergoing ERCP surgery. A total of 27 clinical variables were collected as input variables. Seven models (including univariate analysis and six machine learning models) were trained and tested for classified prediction. The model' performance was measured by AUROC. The RFT model demonstrated excellent performances with accuracies up to 0.86 and AUROC up to 0.87. Feature selection in RF and SHAP was similar, and the choice of the best variable subset produced a high performance with an AUROC up to 0.89. We have developed a hybrid machine learning model with better predictive performance than traditional LR prediction models, as well as other machine learning models for cholangitis based on simple clinical data. The model can assist doctors in clinical diagnosis, adopt reasonable treatment plans, and improve the survival rate of patients. [ABSTRACT FROM AUTHOR]

Background: Whole genome variants offer sufficient information for genetic prediction of human disease risk, and prediction of animal and plant breeding values. Many sophisticated statistical methods have been developed for enhancing the predictive ability. However, each method has its own advantages and disadvantages, so far, no one method can beat others. Results: We herein propose an Ensemble Learning method for Prediction of Genetic Values (ELPGV), which assembles predictions from several basic methods such as GBLUP, BayesA, BayesB and BayesCπ, to produce more accurate predictions. We validated ELPGV with a variety of well-known datasets and a serious of simulated datasets. All revealed that ELPGV was able to significantly enhance the predictive ability than any basic methods, for instance, the comparison p-value of ELPGV over basic methods were varied from 4.853E−118 to 9.640E−20 for WTCCC dataset. Conclusions: ELPGV is able to integrate the merit of each method together to produce significantly higher predictive ability than any basic methods and it is simple to implement, fast to run, without using genotype data. is promising for wide application in genetic predictions. [ABSTRACT FROM AUTHOR]

Electrochemical carbon dioxide (CO2) reduction (eCO2R) over Cu-based bimetallic catalysts is a promising technique for converting CO2 into value-added multi-carbon products, such as fuels, chemicals, and materials. For improving the process efficiency, electrocatalyst development for the eCO2R must be integrated with tuning of operating conditions. For example, CuIn-based materials typically lead to preferential C1 product selectivity, which delivers the desired C2+ products upon varying the In/Cu ratio and operating conditions (i.e., in 0.1 M KHCO3 electrolytes using an H-type cell with a cation exchange membrane vs. in 1 M KOH electrolytes using a flow cell with an anion exchange membrane). At lower Cu-loading (i.e., InCu5Ox material), the maximum faradaic efficiency of HCOOH (FEHCOOH) of 70% was achieved at −1 V versus the reversible hydrogen electrode (vs. RHE) in an H-type cell. However, upon increasing the Cu loading, the preferential product selectivity could be altered: the InCu73Ox material led to a high CO selectivity (maximum FE of 51%) in the H-type cell at −0.8 V vs. RHE and delivered a current density of 100 mA cm−2 with a FEC2+ of up to 37% at −0.8 V vs. RHE in the flow cell configuration. Various characterization tools were also employed to probe the catalytic materials to rationalize the electrocatalytic performance. [ABSTRACT FROM AUTHOR]

The manipulation of coherent multipulse generations is a promising ultrafast pulse technique. In this study, we experimentally obtain for the first time the synthesis of various soliton molecules (SMs) with different pulse spacings and phases based on composite filtering effects in a fiber laser. The composite filtering functions are constructed by multiplying the nonlinear–polarization–rotation (NPR)- and Lyot-based filtering effects to achieve four processes from the coexistence, incoherent interaction, and weakly coherent interaction of two pulses to the generation of an SM. Theoretical and experimental analyses demonstrate that the manipulation of synthesizing SMs is due to the composite filtering functions. Our research provides a novel method for the manipulation of SM generation in a noise-driven nonlinear dissipative system, which has significant applications in the fields of pulse coding and coherent pulse detection. [ABSTRACT FROM AUTHOR]

A novel miniaturized dual‐band quarter‐mode substrate integrated waveguide (QMSIW) bandpass filter with high selectivity is proposed in this letter. Two passbands are generated by the fundamental mode and the first higher order mode of the spiral‐stub‐loaded QMSIW resonator, respectively. Miniaturization is achieved by loading stubs and applying quarter‐mode cavities. High selectivity can be realized by introducing two transmission zeros (TZs) between the two passbands. One TZ is generated by adding coplanar waveguide coupling between the two resonators, the other TZ is synthesized by coupling between the modes of the resonator. The proposed dual‐band filter has the characteristics of miniaturization, high selectivity, and low loss, which is suitable for satellite communication related applications. [ABSTRACT FROM AUTHOR]

The quest for improved heterogeneous catalysts often leads to sophisticated solutions, which are expensive and tricky to scale up industrially. Herein, the effort to upgrade the existing inorganic nonmetallic materials has seldom been prioritized by the catalysis community, which could deliver cost-effective solutions to upgrade the industrial catalysts catalog. With this philosophy in mind, we demonstrate in this work that alloyed palladium-lead (Pd-Pb) deposited on novel precipitated calcium carbonate (PCC) supports could be considered an upgraded version of the industrial Lindlar catalyst for the semi-hydrogenation of phenylacetylene to styrene. By utilizing PCC supports of variable surface areas (up to 60 m2/g) and alloyed Pd-Pb loading, supported by material characterization tools, we showcase that achieving the "active-site isolation" feature could be the most pivotal criterion to maximize semi-hydrogenated alkenes selectivity at the expense of prohibiting the complete hydrogenation to alkanes. The calcite phase of our PCC supports governs the ultimate catalysis, via complexation with uniformly distributed alloyed Pb, which may facilitate the desired "active-site isolation" feature to boost the selectivity to the preferential product. Through this work, we also advocate increasing research efforts on mineral-based inorganic nonmetallic materials to deliver novel and improved cost-effective catalytic systems. [ABSTRACT FROM AUTHOR]

Background: Ligand–protein interactions play a key role in defining protein function, and detecting natural ligands for a given protein is thus a very important bioengineering task. In particular, with the rapid development of AI-based structure prediction algorithms, batch structural models with high reliability and accuracy can be obtained at low cost, giving rise to the urgent requirement for the prediction of natural ligands based on protein structures. In recent years, although several structure-based methods have been developed to predict ligand-binding pockets and ligand-binding sites, accurate and rapid methods are still lacking, especially for the prediction of ligand-binding regions and the spatial extension of ligands in the pockets. Results: In this paper, we proposed a multilayer dynamics perturbation analysis (MDPA) method for predicting ligand-binding regions based solely on protein structure, which is an extended version of our previously developed fast dynamic perturbation analysis (FDPA) method. In MDPA/FDPA, ligand binding tends to occur in regions that cause large changes in protein conformational dynamics. MDPA, examined using a standard validation dataset of ligand-protein complexes, yielded an averaged ligand-binding site prediction Matthews coefficient of 0.40, with a prediction precision of at least 50% for 71% of the cases. In particular, for 80% of the cases, the predicted ligand-binding region overlaps the natural ligand by at least 50%. The method was also compared with other state-of-the-art structure-based methods. Conclusions: MDPA is a structure-based method to detect ligand-binding regions on protein surface. Our calculations suggested that a range of spaces inside the protein pockets has subtle interactions with the protein, which can significantly impact on the overall dynamics of the protein. This work provides a valuable tool as a starting point upon which further docking and analysis methods can be used for natural ligand detection in protein functional annotation. The source code of MDPA method is freely available at: https://github.com/mingdengming/mdpa. [ABSTRACT FROM AUTHOR]

Because of the precise control of film thickness, atomic layer deposition (ALD) offers significant advantages in fabricating high-quality superlattice films. For the first time, a SiN x /SiO 2 superlattice with an ultrathin SiN x sublayer layer (1.5 nm) and a SiO 2 barrier layer (3 nm) was successfully fabricated using plasma-enhanced ALD. Transmission electron microscopy (TEM) measurements demonstrate the maintenance of multilayer structures with smooth interfaces. Next, the annealing effect on the microstructural, optical, and chemical properties of these SiN x /SiO 2 superlattice structures was thoroughly investigated. With increasing annealing temperature, X-ray reflection (XRR) and TEM measurements revealed consistent changes in interface, morphology, roughness, density, and thickness. After high-temperature annealing, Fourier-transform infrared spectroscopy (FTIR) measurements combined with X-ray photoelectron spectroscopy (XPS) measurements revealed significant reductions in Si–H-related defects and absorption bands. Photoluminescence (PL) was used to characterize the light emission property, and it was discovered that increasing the annealing temperature decreased the PL peak intensity at ∼550 and 900 nm. The silicon nanocrystals (Si–NCs)-related PL peak (∼900 nm) became dominant as the annealing temperature increased. The findings in this paper shed light on the annealing effect on the new superlattice material prepared via ALD. Improved PL properties of this type of superlattice are expected and can be obtained in future research by optimizing the ALD deposition process and annealing parameters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu2+ doped molecularly imprinting resin was synthesized with hydrophilic monomers. • Cu-MIR presents special recognition to TCs in environmental water. • Cu-MIR was applied for enrichment of TCs in environmental water with satisfactory recoveries. Antibiotic contamination in environmental waters often occurs at low residue levels, necessitating pre-analysis concentration. To address this, we synthesized a hydrophilic molecularly imprinted resin (MIR) using melamine, urea, and formaldehyde as monomers, with oxytetracycline as the template molecule. Enhanced adsorption efficiency was achieved by doping the resin with Cu2+, which forms stable complexes with oxytetracycline. This Cu2+-doped MIR (Cu-MIR) was employed as a selective adsorbent in solid-phase extraction (SPE) to enrich four tetracycline antibiotics (TCs) from aqueous solutions. The optimized parameters for Cu-MIR in environmental water sample analysis resulted in linear detection ranges from 0.20 to 40 ng/mL, recoveries between 80.2 % to 102.4 %, relative standard deviations ≤ 9.0 %, a detection limit of 0.1 ng/mL, and the enrichment factors were between 4.79–5.13, as determined by HPLC-MS. Given its diverse adsorption mechanisms and specificity, Cu-MIR shows promise for practical applications in real-world sample analysis. [ABSTRACT FROM AUTHOR]

Objective. This study investigated the potential effects of Baicalein on proliferation, migration, and invasion of human lung cancer A549 and NCI-H1299 cells and its possible mechanisms. Methods. The effects of Baicalein on proliferation and invasion of A549 and NCI-H1299 cells were detected by MTT assay, clonogenesis assay, and Transwell assay. A subcutaneous transplanted tumor model was used to evaluate the effects of SMYD2 and Baicalein on the proliferation of lung cancer. Baicalein inhibited in SMYD2/RPS7 signaling pathway in tumor cells was also detected by qRT-PCR. Results. Baicalein significantly inhibited the growth of lung cancer cells. In addition, Baicalein significantly reduced the rate of A549 and NCI-H1299 cell invasion and clone formation in a dose-dependent manner. Animal experiments showed that both SMYD2 and Baicalein treatments could inhibit lung cancer tumor proliferation. Mechanism studies suggest that Baicalein inhibits the SMYD2/RPS7 signaling pathway. Conclusion. These results indicated that Baicalein could inhibit the proliferation, migration, and invasion of LUNG cancer A549 and NCI-H1299 cells. Baicalein inhibits cell proliferation by downregulating the SMYD2/RPS7 signaling pathway. [ABSTRACT FROM AUTHOR]

The volume of medical images stored in hospitals is rapidly increasing; however, the utilization of these accumulated medical images remains limited. Existing content-based medical image retrieval (CBMIR) systems typically require example images, leading to practical limitations, such as the lack of customizable, fine-grained image retrieval, the inability to search without example images, and difficulty in retrieving rare cases. In this paper, we introduce a sketch-based medical image retrieval (SBMIR) system that enables users to find images of interest without the need for example images. The key concept is feature decomposition of medical images, which allows the entire feature of a medical image to be decomposed into and reconstructed from normal and abnormal features. Building on this concept, our SBMIR system provides an easy-to-use two-step graphical user interface: users first select a template image to specify a normal feature and then draw a semantic sketch of the disease on the template image to represent an abnormal feature. The system integrates both types of input to construct a query vector and retrieves reference images. For evaluation, ten healthcare professionals participated in a user test using two datasets. Consequently, our SBMIR system enabled users to overcome previous challenges, including image retrieval based on fine-grained image characteristics, image retrieval without example images, and image retrieval for rare cases. Our SBMIR system provides on-demand, customizable medical image retrieval, thereby expanding the utility of medical image databases. [Display omitted] • We demonstrate a sketch-based medical image retrieval system (SBMIR). • Our SBMIR system provides an easy-to-use two-step graphical user interface. • Our SBMIR system achieves flexible medical image retrieval on demand. [ABSTRACT FROM AUTHOR]

Introduction: Whether and how mesoderm posterior 1 (MESP1) plays a role in the proliferation of gastric cancer cells remain unclear. Methods: The expression of MESP1 was compared in 48 human gastric cancer tissues and adjacent normal tissues. Knockdown of MESP1 was performed to investigate the role of MESP1 in the proliferation and apoptosis of BGC-823 and MGC-803 gastric cancer cells. Knockdown of alternative reading frame (ARF) was performed to study the role of ARF in the inhibitory effect of MESP1 knockdown on cell proliferation in gastric cancer cells. Mouse subcutaneous xenograft tumor model bearing BGC-823 cells was used to investigate the role of MESP1 in the growth of gastric tumor in vivo. The effect of seven active ingredients from T. terrestris on MESP1 expression was tested. The anti-cancer effect of diosgenin was confirmed in gastric cancer cells. MESP1 dependence of the anti-cancer effect of diosgenin was confirmed by MESP1 knockdown. Results: MESP1 was highly expressed in human gastric cancer tissues (p < 0.05). MESP1 knockdown induced apoptosis and up-regulated the expression of ARF in gastric cancer cells (p < 0.05). Knockdown of ARF attenuated the anti-cancer effect of MESP1 knockdown (p < 0.05). In addition, MESP1 knockdown also suppressed tumor growth in vivo (p < 0.05). Diosgenin inhibits both mRNA and protein expression of MESP1 (p < 0.05). MESP1 knockdown attenuated the anti-cancer effect of diosgenin (p < 0.05). Conclusions: MESP1 promotes the proliferation of gastric cancer cells via inhibiting ARF expression. Diosgenin exerts anti-cancer effect through inhibiting MESP1 expression in gastric cancer cells. [ABSTRACT FROM AUTHOR]

Background: The objective of this study was to describe bladder cancer outcomes as a function of race among patients with high‐risk non–muscle‐invasive bladder cancer (NMIBC) in an equal‐access setting. Methods: A total of 412 patients with high‐risk NMIBC who received bacille Calmette‐Guérin (BCG) from January 1, 2010, to December 31, 2015, were assessed. The authors used the Kaplan‐Meier method to estimate event‐free survival and Cox regression to determine the association between race and recurrence, progression, disease‐specific, and overall survival outcomes. Results: A total of 372 patients who had complete data were included in the analysis; 48 (13%) and 324 (87%) were Black and White, respectively. There was no difference in age, sex, smoking status, or Charlson Comorbidity Index by race. White patients had a higher socioeconomic status with a greater percentage of patients living above the poverty level in comparison with Black patients (median, 85% vs 77%; P <.001). A total of 360 patients (97%) received adequate induction BCG, and 145 patients (39%) received adequate maintenance BCG therapy. There was no significant difference in rates of adequate induction or maintenance BCG therapy according to race. There was no significant difference in recurrence (hazard ratio [HR], 1.53; 95% confidence interval [CI], 0.64‐3.63), progression (HR, 0.77; 95% CI, 0.33‐1.82), bladder cancer–specific survival (HR, 1.01; 95% CI, 0.30‐3.46), or overall survival (HR, 0.97; 95% CI, 0.56‐1.66) according to Black race versus White race. Conclusions: In this small study from an equal‐access setting, there was no difference in the receipt of BCG or any differences in bladder cancer outcomes according to race. In this population‐based study within the largest equal‐access setting in the United States, among patients with high‐risk non–muscle‐invasive bladder cancer, there is no difference in age, sex, smoking status, or Charlson Comorbidity Index by race. There is no significant difference in rates of adequate induction or maintenance bacille Calmette‐Guérin therapy or any other outcomes measured according to race. [ABSTRACT FROM AUTHOR]

We examine the effects of computer-based versus paper-based assessment of critical thinking skills, adapted from English (in the U.S.) to Chinese. Using data collected based on a random assignment between the two modes in multiple Chinese colleges, we investigate mode effects from multiple perspectives: mean scores, measurement precision, item functioning (i.e. item difficulty and discrimination), response behavior (i.e. test completion and item omission), and user perceptions. Our findings shed light on assessment and item properties that could be the sources of mode effects. At the test level, we find that the computer-based test is more difficult and more speeded than the paper-based test. We speculate that these differences are attributable to the test's structure, its high demands on reading, and test-taking flexibility afforded under the paper testing mode. Item-level evaluation allows us to identify item characteristics that are prone to mode effects, including targeted cognitive skill, response type, and the amount of adaptation between modes. Implications for test design are discussed, and actionable design suggestions are offered with the goal of minimizing mode effect. [ABSTRACT FROM AUTHOR]

Cloud radio access network (C-RAN) has been widely regarded as a promising techniques for 5G cellular mobile communication. By decoupling radio and baseband processing from all-in-one macro base station into remote radio head (RRH) and baseband unit (BBU) pool, C-RAN can significantly improve the flexibility and scalability of cellular mobile system with less ownership cost and operational expenditure. In 5G systems, the delay tolerance is very strict and usually limited within 5ms; while applications hold different quality-of-service (QoS) towards providing proper service. In terms of this, we classify mobile applications with different priorities, each of which holds a specified delay constraint. Based on network calculus, a theory for deterministic queuing systems, we propose an analysis method revealing delay and backlog upper-bounds for applications with different priorities, indicating the minimum required processing capacity of the C-RAN system. Numerical analysis and experiments driven by real data trace are conducted to validate the derived upper-bounds. Experiment results show that the proposed bounds for both delay and backlog in C-RAN hold great potential to guide the mobile network operator for C-RAN deployment and operation. [ABSTRACT FROM AUTHOR]

Recent technology advancements have increased the prospects for automated spoken language technology to provide feedback on speaking performance. In this study we examined user perceptions of using an automated feedback system for preparing for the TOEFL iBT® test. Test takers and language teachers evaluated three types of machine-generated feedback: domain sub-scores, task scores, and scores based on individual linguistic features. Results showed that the vast majority of the participants perceived all feedback types to be useful, although the teachers showed slightly more scepticism than the students. We believe that these findings provide initial support for making such feedback available to those preparing for the TOEFL iBT test or other similar tests of spoken language proficiency. Study outcomes also inform our understanding of the role of technology in test preparation and the extent to which the use of technology changes preparation behaviours and preferences. [ABSTRACT FROM AUTHOR]

[Display omitted] • A comprehensive investigation of Ga 2 O 3 /diamond heterostructures, including microstructure, chemical state, and thermal conductance characteristics, was conducted by combining theory with experiments. • Deep etching analysis revealed the presence of a non-diamond sp2 peak near the interface of the heterostructure. • The heterostructure exhibited a staggered (type Ⅱ) band alignment. • The thermal conductivity of amorphous Ga 2 O 3 was 5.13 W/(m·K) and the TBC of Ga 2 O 3 /diamond was 19.22 MW/(m2·K) from TDTR measurements. In this work, the characteristics of the gallium oxide (Ga 2 O 3)/diamond heterostructure were thoroughly examined after the preparation of Ga 2 O 3 thin film on bulk diamond via atomic layer deposition. The X-ray diffraction (XRD) analysis revealed the Ga 2 O 3 film amorphous and diamond polycrystalline. The atomic force microscopy (AFM) mapping displayed remarkably smooth surfaces of the Ga 2 O 3 film and diamond substrate (RMS of 0.184 and 0.508 nm, respectively). The scanning electron microscopy (SEM) images showed conspicuous grains formed on the diamond, and small crystallites on the surface of the film. The optical characteristics were investigated via spectroscopic ellipsometry (SE) and UV/Vis/NIR spectrophotometer. Raman spectroscopy suggested a sharp diamond-related (sp3) peak and an extremely weak bulge band around 1350–1620 cm−1. X-ray photoelectron spectroscopy (XPS) analysis indicated Ga 2 O 3 /diamond heterojunction to be staggered (type II) band alignment with valence band and conduction band offsets of around 1.18 eV and 2.09 eV, respectively. Moreover, according to time-domain thermoreflectance (TDTR) measurements, the thermal conductivity of Ga 2 O 3 and the thermal boundary conductivity of the heterointerface were 5.13 W/(m·K) and 19.22 MW/(m2·K), respectively. These findings not only demonstrate the feasibility of Ga 2 O 3 -on-diamond hetero-integration but open up new prospects for the design and physical analysis of Ga 2 O 3 /diamond-based devices in the future. [ABSTRACT FROM AUTHOR]

Understanding the effect of glass network structure on the solubility properties of bioactive glasses is fundamental for designing new compositions with tailored biological functions and applications. This paper bridged the composition-structure-property relationship utilizing experimental measurements and molecular dynamics simulations. The Sr atom reorganized the network structures through a partial transformation of tetrahedral to trigonal boron units and the change of the ratio of bridged oxygen/non-bridged oxygen, which modified the glass structures at longer lengths scales, such as through changing the ring size distribution. Our results demonstrated that the evolution of solubility properties can be linked to the atomic structure change in short- and medium-range ordering. The structure-property relationship can be used to design and tune bioactive glass composition with specific properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to propose an effective dynamic calibration and compensation method to solve the problem that the statically calibrated force sensor would produce large dynamic errors when measuring dynamic signals. Design/methodology/approach: The dynamic characteristics of the force sensor are analyzed by modal analysis and negative step dynamic force calibration test, and the dynamic mathematical model of the force sensor is identified based on a generalized least squares method with a special whitening filter. Then, a compensation unit is constructed to compensate the dynamic characteristics of the force measurement system, and the compensation effect is verified based on the step and knock excitation signals. Findings: The dynamic characteristics of the force sensor obtained by modal analysis and dynamic calibration test are consistent, and the time and frequency domain characteristics of the identified dynamic mathematical model agree well with the actual measurement results. After dynamic compensation, the dynamic characteristics of the force sensor in the frequency domain are obviously improved, and the effective operating frequency band is widened from 500 Hz to 1,560 Hz. In addition, in the time domain, the rise time of the step response signal is reduced from 0.29 ms to 0.17 ms, and the overshoot decreases from 26.6% to 9.8%. Originality/value: An effective dynamic calibration and compensation method is proposed in this paper, which can be used to improve the dynamic performance of the strain-gauge-type force sensor and reduce the dynamic measurement error of the force measurement system. [ABSTRACT FROM AUTHOR]

A novel nitrogen-riched composite (PPYTZ/C) was firstly prepared by chemical polymerization, and then the Cu-PPYTZ/C complex was obtained by immersing the PPYTZ/C modified electrode in copper sulphate solution. For comparing the performance of the two catalysts, physical and electrochemical measurements were adopted. Wherein, physical measurements include scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS). And, the electrochemical measurements include cyclic voltammetry (CV), rotating disk electrode (RDE) and rotating ring-disk electrode (RRDE), and then the above measurement results were compared with commercial Pt/C. The CV and RDE results proved that Cu-PPYTZ/C catalyst exhibits excellent performance than that of PPYTZ/C in term of ORR activities and stability. In addition, the RRDE results also indicated that Cu-PPYTZ/C is comparable to the commercialization Pt/C in term of electron transfer numbers. In conclusion, Cu-PPYTZ/C is the potential candidate for oxygen reduction reaction catalysts, which is attribute to the role of CNx-M in Cu-PPYTZ/C catalyst as the catalytic group. [ABSTRACT FROM AUTHOR]

Li4Ti5O12 is a promising anode for lithium‐ion batteries due to its zero‐strain properties. However, its low conductivity has greatly affected its rate performance. At the same time, the electrolyte decomposition during cycling also needs to be solved, especially at low cut‐off voltage. Herein, using a high‐throughput two‐step method, we synthesized Zr‐doped LTO modified by mesoporous LiBaF3 nanoparticles for alkali‐ion storage. The doping of Zr can enhance the electronic conductivity and facilitate the rate performance. Meanwhile, the coating of mesoporous LiBaF3 nanoparticles can form a mesoporous surface with large pore size (ca. 3–10 nm), which can benefit the alkali ion diffusion and simultaneously restrain the formation of an excess solid electrolyte interface to a reasonable range. The optimized material is used as an advanced anode for both lithium‐ion and potassium‐ion batteries, and good battery behavior including high‐rate performance and high stability is achieved. [ABSTRACT FROM AUTHOR]

It is well known that xylem embolism can be repaired by bark water uptake and that the sugar required for embolism refilling can be provided by corticular photosynthesis. However, the relationship between corticular photosynthesis and embolism repair by bark water uptake is still poorly understood. In this study, the role of corticular photosynthesis in embolism repair was assessed using Salix matsudana branch segments dehydrated to −1.9 MPa (P50, water potential at 50% loss of conductivity). The results indicated that corticular photosynthesis significantly promoted water uptake and nonstructural carbohydrate (NSC) accumulation in the bark and xylem during soaking, thereby effectively enhancing the refilling of the embolized vessels and the recovery of hydraulic conductivity. Furthermore, the influence of the extent of dehydration on the embolism refilling enhanced by corticular photosynthesis was investigated. The enhanced refilling effects were much higher in the mildly dehydrated (−1.5 MPa) and moderately dehydrated (−1.9 MPa) branch segments than in the severely dehydrated (−2.2 MPa) branch segments. This study provides evidence that corticular photosynthesis plays a crucial role in xylem embolism repair by bark water uptake for mildly and moderately dehydrated branches. Corticular photosynthesis promoted water uptake and nonstructural carbohydrate (NSC) accumulation in the bark and xylem of dehydrated Salix matsudana branch segments during soaking. Maintenance of corticular photosynthesis in the wetted branch segments effectively enhanced the refilling of embolized vessels and the recovery of hydraulic conductivity. [ABSTRACT FROM AUTHOR]

Highlights • A coupled electrode-plasma-workpiece model is proposed to study the plasma channel. • The equilibrium discharge numerical simulation is applied in the coupled model. • The electrical energy-thermal energy conversion and heat transfer is analyzed. • The temperature distribution of plasma channel, electrode and workpiece are obtained. • An observation experiment is conducted to verify the simulation results. Abstract A coupled electrode-plasma-workpiece mathematical model was proposed to study the development of arc plasma channels and the formation of discharge craters. In order to avoid deviations caused by heat source empirical equations and discrepancies in energy distribution type, a reliable simulation based on equilibrium discharge conditions was utilized to reveal the arc discharging process. To better describe this coupled model, the basic theoretical analysis of arc discharging was first introduced, after which the multi-field coupling and governing equations of arc discharging model were studied. Based on the simulation results, researchers investigated the heat transferred from the arc plasma channel to the workpiece and electrode and obtained the arc plasma shape. The discharge crater on the workpiece and the electrode erosion process were also analyzed. Additionally, a single arc discharging experiment was conducted in order to verify the simulation results. The experiment results reflect that the arc plasma shape and discharge crater morphology fits with the simulation results. The comparison indicates that the coupled electrode-plasma-workpiece model was effective in analyzing the arc discharging process. [ABSTRACT FROM AUTHOR]

With the advent of edge computing, it is highly recommended to extend some cloud services to the network edge such that the services can be provisioned in the proximity of end users, with better performance efficiency and cost efficiency. Compared to cloud computing, edge computing has high dynamics, and therefore the resources shall be correspondingly managed in an adaptive way. Traditional model-based resource management approaches are limited in practical application due to the involvement of some assumptions or prerequisites. We think it is desirable to introduce a model-free approach that can fit the network dynamics well without any prior knowledge. To this end, we introduce a model-free DRL approach to efficiently manage the resources at the network edge. Following the design principle of DRL, we design and implement a mobility- aware data processing service migration management agent. The experiments show that our agent can automatically learn the user mobility pattern and accordingly control the service migration among the edge servers to minimize the operational cost at runtime. Some potential future research challenges are also presented. [ABSTRACT FROM AUTHOR]

Blasting erosion arc machining (BEAM) is a novel and promising electrical machining process for difficult-to-cut material processing. In this research, air is applied as an alternative dielectric to investigate the feasibility of dry BEAM. An arc plasma observation experiment is designed and conducted based on a four-channel intensified charge-coupled device (ICCD) high-speed camera in order to observe and investigate the arc plasma expansion and deflection behavior. Furthermore, the influence of the aerodynamic force on plasma column deflection is also studied through comparing the images under different airflow velocities. Voltage and current waveforms were captured to verify the positive effect of air flushing on plasma channels' deflection behavior. Additionally, crater geometries on the workpiece and electrodes were also observed and discussed as a means to analyze the effect of airflow on machining characteristics. The experimental results reflected that aerodynamic arc disturbing mechanism can be realized in air flushing BEAM, which is a promising process of working fluid for BEAM. [ABSTRACT FROM AUTHOR]

Abstract In this study, we synthesized a nitrogen rich compound (FPPHA) as the precursor of oxygen reduction reaction (ORR) catalysts, which was prepared based on 1,10-phenanthroline-5-amine and 2,2'-bipyridyl-5,5'-dialdehyde. The FPPHA-Fe complex was formed and be loaded on the carbon powder to form the FPPHA-Fe/C composite catalyst. The pyrolysis of the FPPHA-Fe/C composite was conducted at different temperatures, including 700 °C, 800 °C, and 900 °C, and the resultant pyrolyzed materials were designated to FPPHA-Fe/C-700, FPPHA-Fe/C-800, FPPHA-Fe/C-900, respectively. The physical characteristics of the catalysts were examined by powder X-ray diffraction (PXRD), Brunauer–Emmett–Teller analysis, X-ray photoelectron spectrometer (XPS) and scanning electron microscopy (SEM) etc. The ORR performance of the composite catalysts were evaluated by cyclic voltammetry (CV), linear sweep voltammetry (LSV), and rotating ring disk electrodes (RRDE) in an alkaline solution. The results suggested that the pyrolysis process has a positive effect on the ORR activity of the catalysts, and among the catalysts the Fe-FPPHA/C-800 had the most preferable performance, which reduces oxygen through a predominantly four electron pathway with an average electron transfer number of 3.86 and an average hydrogen peroxide yield of 6.7%. Graphical abstract Image 1 Highlights • A N-containing ligand (FPPHA) was prepared based on phenanthroline and bipyridine. • The complex Fe-FPPHA was prepared and be loaded on carbon powder as ORR catalyst. • The Fe-FPPHA/C-800 was obtained through the pyrolysis of the Fe-FPPHA/C catalyst. • The ORR performance of the catalyst could be improved through the pyrolysis process. • Maximum power density of PEMFC achieved 0.078 W cm−2 at 50 °C without backpressure. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Radical assisted iron impregnation was used to prepare sludge precursors. • Radical oxidation promoted enhanced Fe3+ interaction with disintegrated sludge flocs. • The resulted catalyst had Fe NPs uniformly encapsulated in carbon matrix. • The resulted catalyst had much improved stability and activity. • Fe NPs distributed in pores facilitate the polar interaction with organic acids. Abstract Radical induced sewage sludge pretreatment has been developed to enhance sludge stabilization and dewaterability. Except for anaerobic digestion, the reutilization of the oxidized sludge residuals is still a challenging issue for wastewater treatment plant. In the view of favorable role in sludge disintegration, the pretreated sludge precursors, which was obtained by sequential radical oxidation and iron impregnation, was carbonized to prepare the carbon encapsulated Fe nanoparticles (Fe NPs), which could then behave as highly stable and active heterogeneous Fenton-like catalyst to degrade Black-T. By contrast, the carbonized products derived from direct iron impregnation were also prepared as a control method. The effect of H 2 O 2 /Fe2+ on zeta potential, particle size, morphology and texture structure of the pretreated sludge precursors and their corresponding influence on the carbonized materials were systematically evaluated. Results showed that radicals’ activation could facilitate the iron impregnation on sewage sludge by rupturing the microbial aggregate and making them more accessible to subsequent microbial fragments. Compared to direct iron impregnation, the carbonized products featured much higher iron insertion rate and the uniformly dispersed Fe NPs encapsulated into porous carbons, which in turn enables catalysts exhibiting more efficient catalytic activity in continuous heterogeneous Fenton-like degradation and resistance to metal leaching. [ABSTRACT FROM AUTHOR]

Electrical arc machining has shown its remarkable efficiency in processing difficult-to-cut materials, especially high-temperature alloys and metal-based composites. Despite several studies about the material removal mechanisms of the electrical arc machining of metal alloys, few of these reports relate to the mechanism of machining composites with electrical arcing. Considering that reinforcements such as SiC particles have different thermal and electrical properties with metal alloys, research on the influence of SiC reinforcement on the electrical arc machining process is important and necessary. Based on comparison experiments using 20 and 50 vol.% SiC/Al composites, this research focused on the influence of SiC particles on the machining performance and material removal mechanism of blasting erosion arc machining (BEAM), and further analyzed the influence of reinforcements on composite material removal mechanisms. Analysis revealed that the molten material expelling mechanism is also influenced by the SiC fraction difference. For the BEAM of lower SiC fraction composites, both the SiC particles and the molten aluminum are mainly pumped and ejected by the flushing dielectric. In greater SiC fraction composites, most SiC particles are directly sublimed by heat. In addition, the mechanism of BEAM in the material removal and tool wear of SiC/Al composites was discussed based on heat transfer simulation and observation. Furthermore, the results disclosed that many chemical reactions take place during machining that have an obvious influence on the tool wear rate. [ABSTRACT FROM AUTHOR]

Abstract: Understanding the reaction processes of electrode and electrolyte materials is important for achieving high‐performance lithium‐ion batteries (LIBs). Currently, transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) can readily characterize the structural and chemical features of these materials from the micrometer scale to the atomic scale. In situ (S)TEM can further monitor their non‐ or quasi‐equilibrated states in real time. Here, the recent progress in unraveling the crystal and electronic structures of the electrode and solid‐electrolyte materials using ex situ and in situ (S)TEM is reviewed. Three fundamental functions, including imaging, diffraction, and spectroscopy, are jointly used to decipher the configuration of the defects and ordering, the variations near the surfaces and across the interfaces, and the evolution of the coexisting phases. Novel and deep insights are proposed for the material growth, reaction, and capacity fading mechanisms. Advanced (S)TEM studies for LIB materials pose numerous challenges and perspectives, including the development and application of local diffraction analysis, large‐scale phase mapping techniques, 3D reconstruction, and cryoelectron microscopy, which are further discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • In macro-scale, a unified rule is developed on the basis of effective strain energy density. • A new fatigue indicator parameter is proposed in crystal plasticity simulation framework. • The present rule is more accurate than existing ones for both low-cycle and high-cycle fatigue. This paper develops a unified rule for both low-cycle fatigue and high-cycle fatigue life prediction from macro-scale to micro-scale. In the macro-scale, the unified rule is proposed on the basis of the concept of the effective strain energy density. In the micro-scale, the unified rule represented by a new fatigue indicator parameter is developed by considering the combined effects of the energies in shear and normal directions for individual slip systems. A large number of low-cycle and high-cycle fatigue experimental data of Inconel 718 superalloy at room temperature is used to verify the prediction capacities of the newly unified rule. Compared with the prediction accuracy of the existing fatigue damage models, the unified rule shows more accurately predicted results for both low-cycle and high-cycle fatigue life. Most of the fatigue experimental data falls into a range within a scatter band of ±3 on life. [ABSTRACT FROM AUTHOR]

• Manipulation of the generation of tunable soliton molecules based on the self-constructed compound filtering. • Constructing compound filtering by incorporating nonlinear polarization rotation filtering into two-stage Lyot filtering. On-demand soliton molecule (SM) generation is an advanced coherent multipulse technique in the field of nonlinear optics. Experimentally generating controllable SMs is a significant challenge. Here, we propose to manipulate the generation of tunable SMs in a mode-locked fiber laser based on the self-constructed cascaded compound filtering effect. The cascaded compound filter is achieved by incorporating nonlinear polarization rotation (NPR) filtering into two-stage Lyot filtering for performing a multiplication operation between these two filtering functions. Tunable SMs with flexible parameters of the internal soliton spacings from 4.64 to 6.47 ps, pulse numbers from 2 to 26 and some special phases of ∼ π and ∼ 0.5π are experimentally created on demand by adjusting the cascaded compound filtering profiles. The simulation of SM generation in a fiber laser is carried out to reproduce the transient processes of experimental observations, which reveals that cascaded compound filtering is beneficial for manipulating the generation of SMs. Our research provides a good platform for studying coherent multipulse generation in a dissipative nonlinear system and a novel method for manipulating tunable SM generation. [ABSTRACT FROM AUTHOR]

Melatonin is a stress‐related hormone that plays a critical role in triggering the plant defence system and regulating secondary metabolism when plants are exposed to stress. To explore the potential roles of melatonin in response to Ultraviolet‐B (UV‐B) radiation, we examined the effects of exogenous melatonin on rosemary in vitro shoots under UV‐B stress. The application of melatonin (50 μM) alleviated the adverse effects of UV‐B stress on the biomass, photosynthetic pigment contents, and membrane lipids of the rosemary in vitro shoots. Melatonin significantly increased superoxide dismutase (1.15.1.1, SOD), peroxidase (1.11.1.7, POD), and catalase (1.11.1.6, CAT) activities by 62%, 99%, and 53%, respectively. The contents of total phenols, rosmarinic acid, and carnosic acid increased under UV‐B stress, and they further increased by the melatonin treatment by 41%, 68%, and 67%, respectively, compared with the control group. Under UV‐B stress, the increased total phenol content in melatonin‐pretreated plants could be attributed to the activation of phenylalanine ammonia‐lyase (4.3.1.5, PAL) and tyrosine aminotransferase (2.6.1.5, TAT). In addition, melatonin enhanced the antioxidant and antibacterial activities of the rosemary in vitro shoots under UV‐B stress. These results suggest that melatonin can alleviate the damage caused by UV‐B stress and also enhance the secondary metabolism and bioactivity of rosemary in vitro shoots. [ABSTRACT FROM AUTHOR]

The hydrothermal carbonization (HTC) was performed on Metasequoia Leaves (ML) in the presence of iron sludge, both of which were generated as solid residuals. The relations between sludge, char’s properties and operating conditions were systemically investigated. Iron sludge primarily catalyzed the efficient formation of char with higher heating value (HHV) becoming 1.15–1.65 times of ML (18.21 MJ/kg) and was meanwhile reduced to magnetite. The hydrated Fe ions in octahedron crystals acted as nucleophiles facilitating the dehydration and decarboxylation reactions. The increased HHV is found strong temperature dependent while prolonging the residence time is more preferable for low organic acids generation. Thermogravimetric analysis confirmed the iron sludge enhanced conversion of volatile to fixed carbon. The as-prepared solid char showed better stability after catalytic HTC treatment, having ignition temperature increased from 253 to 426 °C as compared to the char prepared without iron sludge addition. [ABSTRACT FROM AUTHOR]

ABSTRACT: Controllable synthesis of bio‐based polylactide (PLA) diols was realized by the ring‐opening polymerization (ROP) of lactide (LA) in the presence of 1,4‐butanediol (BDO) using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) as an organocatalyst in solvent‐free conditions. The catalytic activity and conversion of LA could reach ∼1 kg g−1 DBU and >97%, respectively, and the polymerization yielded polymers with narrow polydispersity index (PDI) (1.15–1.29). Interestingly, the number average molecular weight (Mn) of the obtained PLA diol was in excellent linear relation with the molar ratio of LA and BDO, and hence can be precisely controlled. The structure of the diol was clearly confirmed by 1H and 13C NMR, FTIR, and MALDI‐TOF mass spectra, proving BDO as an initiation‐transfer agent to participate in the polymerization. Kinetic study of the ROP demonstrates a pseudo‐first‐order kinetic model and a controlled “living” nature. Notably, it is found that the glass transition temperature (Tg) of the diol significantly depends on the Mn. Furthermore, various chain transfer agents and organocatalysts can also be used to successfully synthesize well‐defined PLA diols. Especially, functional bio‐based dihydric alcohols such as 2,5‐furandimethanol (FDMO)‐initiated ROP in this system could result in fully bio‐based PLA diols with functionality. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 968–976 [ABSTRACT FROM AUTHOR]

In this study, a combined method is proposed for the machining of SiC/Al matrix composites to achieve high efficiency and better surface quality based on blasting erosion arc machining (BEAM) and computer numerical control (CNC) milling. The combined method consists of two stages. BEAM is adopted in the first stage to achieve a high machining efficiency. During this stage, the negative BEAM is used for improving material removal rate (MRR) while positive BEAM is adopted to reduce roughness of machined surface. In the second stage, CNC milling is utilized to achieve a fine surface. Firstly, in order to perform the combined processing, a special machine tool system is designed. Secondly, machining efficiency of the combined processing is discussed. It is disclosed that in the negative BEAM step, when peak current is 600 A, MRR of 20 vol.% SiC/Al and 50 vol.% SiC/Al composites can be as high as 10,200 and 7500 mm3/min separately. Thirdly, comparison experiments are designed and surface integrity (e.g., surface topography, surface roughness, heat affect zone, surface hardness, compositions) of each machining stage is analyzed. It is demonstrated that in the CNC milling stage, side effects of BEAM on the workpiece (e.g., rough surface, thick heat affect zone) can be eliminated effectively. The roughness of the machined surface can be lower than Ra 0.5 μm; heat affect zone (HAZ) and debris almost cannot be observed. Finally, a SiC/Al workpiece is machined to demonstrate the advantages of the combined machining of SiC/Al matrix composites. [ABSTRACT FROM AUTHOR]

Among the numerous iron-based materials for persulfate (PS) activation, mackinawite (FeS) particles have gained considerable interest as a ubiquitous natural mineral due to their high reactivity. However, the iron and sulfur co-mediated reaction mechanism of PS activation by FeS remains ambiguous. In this study, FeS was applied as a catalyst to activate PS for p -chloroaniline (PCA) degradation and mineralization over a wide initial pH range (3.0–11.0). The reaction was found to follow pseudo-first-order kinetics, with rate constants ranging from 0.0044 to 0.0144 min −1 . The reaction mechanism was elucidated by electron spin resonance (ESR) and quenching studies. A heterogeneous activation mechanism, in which surface Fe(II) species activated PS to produce OH ads and SO 4 − ads , controlled by surface reaction and diffusion was proposed, whereas OH free and SO 4 − free diffusing from the FeS surface were mainly responsible for PCA degradation. The sulfur-mediated cycling of iron species was investigated by comparing PS activation by zero-valent iron (ZVI) and FeS, exogenous Fe(III) addition and X-ray photoelectron spectroscopy (XPS). The results suggested that Fe(II) and S(-II) experienced independent oxidations and that S(-II) species could regenerate Fe(II) from Fe(III) at the FeS surface. Therefore, the S(-II)-promoted Fe(II)/Fe(III) cycle resulted in less PS decomposition but a higher PCA mineralization efficiency. The findings of this study elucidated the novel surface activation mechanism of PS by FeS and provided useful information for utilizing FeS to remediate contaminated water. [ABSTRACT FROM AUTHOR]

Objective Treatment guidelines recommend surgical resection in select cases of stage IV non-small-cell lung cancer (NSCLC) but are based on limited evidence. This study evaluated outcomes associated with surgery in stage IV disease. Methods Factors associated with survival of stage IV NSCLC patients treated with surgery in the National Cancer Date Base (2004–2013) were evaluated using multivariable Cox proportional hazards analyses. Outcomes of the subset of patients with cT1-2, N0-1, M1 and cT3, N0, M1 disease treated with surgery or chemoradiation were evaluated using Kaplan-Meier analyses. Results The five-year survival of all stage IV NSCLC patients who underwent surgical resection (n = 3098) was 21.1%. Outcomes were related to the locoregional extent of the primary tumor, as both increasing T status (T2 HR 1.30 [p < 0.001], T3 HR 1.28 [p < 0.001], and T4 HR 1.28 [p < 0.001], respectively, compared to T1) and nodal involvement (N1 HR 1.34 [p < 0.001], N2 HR 1.50 [p < 0.001], and N3 HR 1.49 [p < 0.001], respectively, compared to N0) were associated with worse survival. Outcomes were also related to the extent of surgical resection, as pneumonectomy (HR 1.58, p < 0.001), segmentectomy (HR 1.36, p = 0.009), and wedge resection (HR 1.70, p < 0.001) were all associated with decreased survival when compared to lobectomy. The five-year survival of cT1-2, N0-1, M1 and cT3, N0, M1 patients was 25.1% (95% CI: 22.8–27.5) after surgical resection (n = 1761) and 5.8% (95% CI: 5.2–6.5) after chemoradiation (n = 8180). Conclusions Surgery for cT1-2, N0-1, M1 or cT3, N0, M1 disease is associated with a 5-year survival of 25% and does not appear to compromise outcomes when compared to non-operative therapy, supporting guidelines that recommend surgery for very select patients with stage IV disease. However, surgery provides less benefit and should be considered much less often for stage IV patients with mediastinal nodal disease or more locally advanced tumors. [ABSTRACT FROM AUTHOR]

The evolution of oxygen-functioning groups in sewage sludge based carbon is influenced by minerals presented in the raw sludge. In this study, the FeCl 3 and polyacrylamide conditioned sludge in real wastewater treatment plant and demineralized sludge were carbonized in the temperature range of 300 °C–800 °C to investigate the roles of temperature and ash components on the interactions between surface groups conversion and crystalline structure evolution. The temperature-dependent ash effect on the conversion of oxygen containing groups was found by using XPS, Boehm titration, XRD and TPR characterization. The phase transfer of hematite to magnetite promoted the formation of hydrophilic organic groups at 600 °C, which may play a significant role on carbon’s adsorptive and catalytic behavior. To gain an in-depth knowledge and understanding, the as-prepared carbon was used as heterogeneous catalyst in persulfate degradation of a model pollutant 2-Naphthol. The use of carbon obtained at 600 °C (MC600) can achieve 88.7% and 47% of 2-Naphthol and TOC removal respectively at neutral pH, far higher than that of MC prepared at 300 and 800 °C. Further research revealed a strong correlation between adsorptive and catalytic efficiency of MC and its mineral structure, surface functional groups as well as operating pH. The formed hydrophilic oxygen-containing groups at higher temperature of MC600 are responsible for 2-Naphthol retention and the hydrogen bonds in siloxane bridges can easily adsorb persulfate. The pH effect on degradation in the presence of persulfate verified the broad pH operation, which is apparently superior than conducting with traditional heterogeneous Fenton process. The quenching experiments and EPR spectrum were further used to detect the oxidative species SO 4 - and HO , and confirmed the catalytic role of MC. [ABSTRACT FROM AUTHOR]

Li ion batteries are important components of portable devices, electric vehicles, and smart grids owing to their high energy density, excellent cyclic performance, and safe operation. However, further development of electrode materials for these batteries is needed to satisfy continually increasing performance demands. Typically, both the charge/discharge kinetics and structural stability of these electrode materials depend on the transport and storage properties of the Li ions. High-spatial-resolution information on structural changes and on the strong interaction between electrons and ions is essential for a better understanding of the electrochemical performance of rechargeable batteries. In this article, we review the known atomic-scale structural changes of these electrode materials during the charge/discharge process, with special emphasis on ion/electron interactions. [ABSTRACT FROM AUTHOR]

• Synthetizing a composite filtering function by manipulating two filtering effects. • Constructing single-wavelength h-shaped pulses by overlapping two filtering effects. • Constructing dual-wavelength h-shaped pulses by multiplying two filtering effects. For the first time, to the best of our knowledge, we experimentally report the optical manipulation of h-shaped pulse generation in passively mode-locked fiber lasers (PMLFLs) by constructing composite filtering functions. Different composite filtering functions can be synthetized by manipulating the superposition or multiplication between different independent filtering effects in the laser cavity. Various types of h-shaped pulses, i.e., single- or dual-wavelength h-shaped pulses, can be dynamically manipulated to generate. Single-wavelength h-shaped pulses with a spike pulse and a flat-top bunch as leading and tailing edges are generated by synthetizing the superposition of F – P- and nonlinear-polarization-rotation (NPR)-based filtering effects. On the other hand, dual-wavelength h-shaped pulses operating at heterogeneous or homogeneous pulse states are formed by constructing the multiplication between Lyot- and NPR-based filtering effects. Experimental and theoretical analyses demonstrate that the synthetized composite filtering functions are beneficial to the artificial manipulation of generating different types of h-shaped pulses. Our work contributes to a deeper understanding of the dynamics of h-shaped pulses and provides an efficient way to generate nonlinear pulses with special profiles. [ABSTRACT FROM AUTHOR]

We focus on the challenging problem of filamentary structure segmentation in both 2D and 3D images, including retinal vessels and neurons, among others. Despite the increasing amount of efforts in learning based methods to tackle this problem, there still lack proper data-driven feature construction mechanisms to sufficiently encode contextual labelling information, which might hinder the segmentation performance. This observation prompts us to propose a data-driven approach to learn structured and contextual features in this paper. The structured features aim to integrate local spatial label patterns into the feature space, thus endowing the follow-up tree classifiers capability to grouping training examples with similar structure into the same leaf node when splitting the feature space, and further yielding contextual features to capture more of the global contextual information. Empirical evaluations demonstrate that our approach outperforms state-of-the-arts on well-regarded testbeds over a variety of applications. Our code is also made publicly available in support of the open-source research activities. [ABSTRACT FROM AUTHOR]

To support the ever-increasing data traffic demands, the Internet has been experiencing a rapid growth in recent decades. Effective and efficient monitoring is highly needed in order to properly manage such complex infrastructure. It is of theoretical and practical significance to derive network device importance (i.e., node rank) for resource utilization optimization, user experience improvement, and security enhancement. Recent development in the Internet infrastructure has introduced prosperous in-network computation resources across the network. To exploit such distributed resources, in this article, we propose a core-graphbased framework, called FRank, for fast node ranking algorithms, which accelerates convergence and reduces communication cost by converting most inter-partition state change propagations into intra-partition ones. We have implemented FRank in a cluster to validate its correctness and efficiency. The experiment results demonstrate that at the least FRank reduces the execution time of existing cutting-edge methods by 30.2 percent with 43.5 percent less communication cost. [ABSTRACT FROM AUTHOR]

Machining of metal matrix composite is a big challenge in industry for the high cutting tool cost and limited machining efficiency. In this study, blasting erosion arc machining (BEAM) was applied to improve the machining efficiency of SiC/Al composite. The performance of BEAM under negative and positive electrode machining conditions was investigated, and two sets of 3-factor, 2-level full factorial experiments were conducted to disclose the effects between the machining parameters. When the peak current was 500 A and the tool polarity was negative, the obtained MRR (material removal rate) was greater than 8270 mm/min, and the TWR (tool wear ratio) was about 2 %. The competitive efficiency and economy of BEAM indicate the potential of electrical arcing in handling difficult-to-cut composite materials. The optimization of machining conditions can result in a high MRR which arrived to 10, 200 mm/min, and the specific MRR was nearly three times of that of EDM. Furthermore, it was disclosed that the MRR in both negative and positive machining was sensitive to the peak current, pulse duration, and pulse interval while the TWR was appeared to be stable as the machining conditions varies within a certain range. The surface topography of the machined workpiece indicates that compared to the negative BEAM, positive BEAM creates a smoother surface under the same machining conditions. Furthermore, in order to study the influence of SiC particles on the machining performance, a complementary experiment was conducted to compare the craters formed on 20 vol.% SiC/Al and pure aluminum. Based on the comparison results, it can be deduced that the discharging condition is possibly influenced by the SiC particles and result in smaller craters. Finally, a workpiece was machined to demonstrate the advantages of BEAM for the machining of SiC/Al composites. [ABSTRACT FROM AUTHOR]

Traditional standalone embedded system is limited in their functionality, flexibility, and scalability. Fog computing platform, characterized by pushing the cloud services to the network edge, is a promising solution to support and strengthen traditional embedded system. Resource management is always a critical issue to the system performance. In this paper, we consider a fog computing supported software-defined embedded system, where task images lay in the storage server while computations can be conducted on either embedded device or a computation server. It is significant to design an efficient task scheduling and resource management strategy with minimized task completion time for promoting the user experience. To this end, three issues are investigated in this paper: 1) how to balance the workload on a client device and computation servers, i.e., task scheduling, 2) how to place task images on storage servers, i.e., resource management, and 3) how to balance the I/O interrupt requests among the storage servers. They are jointly considered and formulated as a mixed-integer nonlinear programming problem. To deal with its high computation complexity, a computation-efficient solution is proposed based on our formulation and validated by extensive simulation based studies. [ABSTRACT FROM PUBLISHER]

Blasting erosion arc machining (BEAM) is a novel high efficiency electrical erosion process, which is characterized by a powerful multi-hole inner flushing. In order to study the influence of the high-velocity flushing on the performance of BEAM, a single discharge experiment is carried out on a specially designed observation apparatus, and the phenomena that occurred during the discharge is observed using a high-speed video camera. During the discharge process, a spray cloud of the removed debris near the downstream side of the discharging point is captured by the camera. Tail shaped crater and erosion-corrosion features are also found on the workpiece and electrode surfaces, respectively. These observed phenomena imply that the high-velocity flushing can greatly improve the melting metal removal from the molten pool thereby improving the material removal rate (MRR). For purpose of exploring the mechanism behind, the flow field and pressure distribution of the high-velocity flushing are analyzed by using computational fluid dynamic (CFD) method. The analyzed results indicate that a low-pressure suction effect exists on the downstream side of the electrodes. With the help of the low-pressure suction effect, the high-velocity flushing can continuously take the molten metal out of the molten pool during the discharge, resulting in the reduction of the overheating of the molten metal and improve the efficiency of the discharging energy. Thereby, the work in this paper helps to explain why the high-velocity flushing can markedly promote the material removal rate. [ABSTRACT FROM AUTHOR]

Blasting erosion arc machining (BEAM) was applied to improve the machining efficiency of Ti-6Al-4V alloy. 5-factor, 2-level fractional factorial experiment was firstly employed to find out the main factors for MRR (material removal rate). According to the results of fractional factorial experiment, 3-factor, 2-level full factorial experiment was conducted to find out the relationship between machining performance and the main factors (peak current, pulse duration, and pulse interval) under the negative electrode machining. Results revealed that when peak current was 500 A and pulse duration was 8 ms, MRR could achieve 16,800 mm/min, which means the specific energy efficiency was 33.6 mm/(A · min). Then, MRR was optimized base on MATLAB optimization toolbox and could reach 20,100 mm/min when adopting the optimized parameters (peak current 600 A, pulse duration 8.8 ms, and pulse interval 3.0 ms). Although TWR (tool wear ratio) can be effected by the machining parameters, it appeared to be stable (around 3 ± 1 %). Besides, the polarity effect was also studied, and flow field simulations were employed to illustrate the influence of feeding direction on the surface roughness. In addition, the machined surface was analyzed by utilizing SEM, EDS, XRD, etc. Results of the surface analysis disclosed that the oxygen content in the negative electrode machined surface was obviously higher than that in the positive electrode machined surface. Since the positive electrode machined surface was much smoother, it can be used to improve the surface quality while the negative electrode machining is suitable for the bulk material removal with high energy. Finally, a Ti-6Al-4V turbine blade sample was machined to demonstrate the feasibility of high efficiency BEAM in difficult-to-cut material processing. [ABSTRACT FROM AUTHOR]

The effects of post-deposition oxygen annealing temperature on the physical, chemical, and optical properties of gallium oxide (Ga 2 O 3) films were systematically studied in this work. First, Ga 2 O 3 films were deposited on Si (100) substrates by atomic layer deposition (ALD) and then annealed at 500–900 ℃, respectively. Several standard surface analysis methods were used to characterize the Ga 2 O 3 films before and after annealing. X-ray diffraction (XRD) patterns illustrated that the as-deposited amorphous film transitioned to β-phase after annealing at temperatures greater than 600 ℃. Atomic force microscopy (AFM) images showed that the grain size and roughness of the films significantly increased when annealed above 700 ℃. Transmission electron microscopy (TEM) tests presented that the interface microstructure was slightly affected by the annealing process. The effects of the annealing process on optical properties were performed using photoluminescence spectroscopy (PL) and spectroscopic ellipsometry (SE). Moreover, X-ray spectroscopy (XPS) was utilized to extract the oxygen vacancy (V O) concentration, bandgap, and the energy band alignment of Ga 2 O 3. With increasing annealing temperature, it was found that the atomic ratio of O/Ga increased while V O decreased monotonically from 47.4 % to 27.0 %. Density functional theory (DFT) simulation further accounted for energy band shifts resulting from the variation of V O. This study provides a means to achieve high-quality β-Ga 2 O 3 films, highly significant for applications of β-Ga 2 O 3 -based ultraviolet photodetectors and other relevant devices. • The temperature-dependent annealing effect on chemical state, microstructure, and optical properties of Ga 2 O 3 film is systematically studied. • The relationship of the band structure with annealing temperature and oxygen vacancy defects is established. • The energy bandgap of Ga 2 O 3 can be tuned from 4.75 eV to 4.94 eV by controlling the annealing temperature. • The DFT theoretical calculation combined with XPS results gives insight into the effect of oxygen vacancy defects on the properties of the Ga 2 O 3. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Co N C catalyst had been developed using an inexpensive and N -rich precursor. • The covalent triazine-based framework provided high density and evenly distributed M N C sites. • The HAT-CN-Co/C-800 catalyst showed the highest ORR activity close to Pt/C. The preparation of non-noble metal catalysts with performance in the oxygen reduction reaction (ORR) comparable or superior to platinum-based catalysts remains challenging. In the present study, hexaazatriphenylenehexacarbonitrile (HAT-CN), which is rich in both cyano groups and pyrazine units, was used as the precursor and then cyclotrimerized into a covalent triazine-based framework with a macrocyclic structure containing abundant complexation sites for transitional metal ions. Subsequently, a series of non-platinum Co N C type catalysts (HAT-CN-Co/C) were prepared, and then pyrolyzed at different temperatures (700 °C, 800 °C, and 900 °C). The pyrolysis treatment endowed the catalysts with activated Co-N x sites, large pore sizes and high specific surface areas, which can promote oxygen transfer and accelerate the ORR catalytic process. It is found that the catalyst (HAT-CN-Co/C-800) obtained from pyrolysis at 800 °C possessed the best ORR activity and followed the four- electrons transfer pathway; the onset potential of ORR was determined as 0.972 V vs reversible hydrogen electrode (RHE), very close to that of Pt/C (0.993 V vs RHE), and the half-wave potential (0.895 V vs RHE) was significantly higher than that of Pt/C (0.859 V vs RHE). Furthermore, the HAT-CN-Co/C-800 catalyst showed good durability (83.2 % current retention after 28000 s) and significant methanol tolerance with good application potential as a substitute for the platinum-based ORR catalyst in fuel cell. [ABSTRACT FROM AUTHOR]

[Display omitted] • The resulting Ru-Ni-Co-P/NC with ultralow Ru SACs is derived from RuNi-ZIF-67. • The CNTs in the Ru-Ni-Co-P/NC sample are in-situ grown during pyrolysis. • The target catalyst feature with defect, charged metal sites and porous texture. • Ru-Ni-Co-P/NC with trace Ru SACs extremely improves OER performance in 1 M KOH. Exploring cost-effective electrocatalysts with robust oxygen evolution reaction (OER) activity is urgent for widespread application for many energy conversion technologies. However, the fundamental understanding on the source of highly active single atoms catalysts (SACs) at the atomic level is still lacking. Herein, an ultralow Ru SACs (0.2 wt%) anchored on transition metal phosphide composite with N -doped carbon matrix (Ru-Ni-Co-P/NC) is derived from RuNi-ZIF-67 via carbonization and subsequent phosphating, which effectively drives OER in the alkaline electrolyte. Abundant carbon defect sites and reorganized electronic structure of metal sites can collectively tailor the OER performance of Ru-Ni-Co-P/NC by structure and electron modulation. As expected, the resulting Ru-Ni-Co-P/NC catalyst delivers 318 mV overpotentials to afford 10 mA cm−2, and exhibits negligible performance degradation for OER. This finding elucidates a rational design of multisite nanomaterials as efficient electrocatalysts, illuminating a potential guide to meet high-performance electrocatalysts. [ABSTRACT FROM AUTHOR]