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Travel time estimation (TTE) is a crucial task in intelligent transportation systems, which has been widely used in navigation and route planning. In recent years, several deep learning frameworks have been proposed to capture the dynamic features of road segments or intersections for travel time estimation. However, most existing works do not consider the joint features of the intersections and road segments. Moreover, most deep neural networks for TTE are designed based on empirical knowledge. Since the independent and joint features of intersections and road segments commonly vary with different datasets, the empirical deterministic neural architectures have limited adaptability to different scenarios. To tackle the above problems, we propose a novel automated deep learning framework, namely Automated Spatio-Temporal Dual Graph Convolutional Networks (Auto-STDGCN), for travel time estimation. Specifically, we propose to construct the node-wise graph and edge-wise graph to characterize the spatio-temporal features of intersections and road segments, respectively. In order to capture the joint spatio-temporal correlations of the dual graphs, a hierarchical neural architecture search approach is introduced, whose search space is composed of internal and external search space. In the internal search space, spatial graph convolution and temporal convolution operations are adopted to capture the respective spatio-temporal correlations of the dual graphs. Further, we design the external search space including the node-wise and edge-wise graph convolution operations from the internal architecture search to capture the interaction patterns between the intersections and road segments. We evaluate our proposed model Auto-STDGCN on three real-world datasets, which demonstrates that our model is significantly superior to the state-of-the-art methods. In addition, we also conduct case studies to visualize and explain the neural architectures learned by our model. [ABSTRACT FROM AUTHOR]

Due to the coupled transformations between metal ions with variable valence states, manganese ferrite (MnFe2O4) is regarded as an efficient catalyst in a heterogeneous Fenton-like system for the degradation of organic contaminants. In this work, the magnetic nanoscale MnFe2O4 was synthesized via a simple hydrothermal method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and vibrating sample magnetometer (VSM). Results on the degradation tests indicated a high catalytic ability of MnFe2O4 nanocrystals to activate hydrogen dioxide (H2O2) to degrade active dye rhodamine B (RhB). Moreover, the RhB degradation process in the MnFe2O4-H2O2 Fenton-like system followed a Behnajady–Modirshahla–Ghanbery (BMG) kinetic model. The catalytic conditions, including catalyst dosage, RhB concentration, H2O2 dosage, solution pH and reaction temperature, had essential effects on RhB degradation efficiency and BMG kinetic parameters. The process optimization of RhB degradation was designed by central composite design (CCD) under response surface methodology (RSM). A mathematic model of the quadratic polynomial was established for the fitting analysis of RhB degradation, which was significant and reliable by the analysis of variance (ANOVA). Based on the programmed prediction, the optimum parameters for RhB degradation in the MnFe2O4–H2O2 system were determined as 2 of solution pH, 19.6 mmol·L−1 of H2O2 dosage, 2.0 g·L−1 of catalyst dosage and 180 min of reaction time. Under these optimum conditions, the predicted and experimental values of RhB degradation efficiency were 99.42% and 98.17%, respectively. [ABSTRACT FROM AUTHOR]

To explore the potential targets and related signaling pathways of Dachaihu Decoction in treating hyperlipidemia, we obtained the active ingredients of the decoction by searching the Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform (TCMSP) for eight Chinese herbal ingredients, namely Radix Bupleuri, Radix Scutellariae, Radix Paeoniae Alba, Rhizoma Pinelliae, Fructus Aurantii Immaturus, Ginger, Jujube, and Rhubarb. To obtain the disease target for hyperlipidemia, we searched the English keyword "hyperlipidemia" and compared and analyzed the drug target of Dachaihu Decoction with the target of hyperlipidemia disease through an online website. We then identified the intersection between the two as the target of Dachaihu Decoction for treating hyperlipidemia. We conducted a topological analysis to screen the key effective components of Dachaihu Decoction for treating hyperlipidemia based on their degree value. Then, the gene targets of Dachaihu Decoction for hyperlipidemia were imported into the String platform to identify the key interaction modules in the PPI network. We also used the cytohubba plug-in to screen the key genes of these modules. The online database platform DAVID was utilized to perform enrichment and analysis of the key module genes with the highest number of genes and scores. The study yielded 116 active ingredients and 294 targets as the drug targets of Dachaihu Decoction. Furthermore, a total of 1349 disease-related gene targets were obtained from the CTD database, OMIM database, and TCMIP platform. After comparing the drug targets of Dachaihu Decoction with the targets related to hyperlipidemia, a total of 168 targets were found to be involved in the treatment of hyperlipidemia by Dachaihu Decoction. Using the MCODE plug -in in Cytoscape software, eight key protein modules were identified in the PPI network. Further analysis of the first key module revealed the top 15 hub genes which may play important roles in the pharmacological effects of Dachaihu Decoction for treating hyperlipidemia. To further understand the underlying mechanism, GO function annotation and KEGG pathway enrichment analysis were performed for the genes included in the key modules using the DAVID database. Based on the GO function annotation, the biological process (BP) of the key module genes was mainly related to the positive regulation of transcription from the RNA polymerase II promoter, the negative regulation of apoptosis, and the response to drugs. The cellular component (CC) was mainly located in the extracellular space, extracellular area, and pits. The molecular function (MF) was mainly focused on enzyme binding, cytokine activity, and protein binding. The KEGG pathway enrichment analysis showed that the key module genes were involved in several signaling pathways, including the hepatitis B signaling pathway, TNF signaling pathway, tumor-related signaling pathway, and PI3K-AKT signaling pathway. These pathways are known to be associated with inflammation, apoptosis, and cell growth, which are all critical processes in the development of hyperlipidemia. In conclusion, it appeared that Dachaihu Decoction could potentially be effective in the treatment of hyperlipidemia by regulating the expression of key genes, such as MMP9 and MAPK2, as well as the PI3K-AKT and TNF signaling pathways. [ABSTRACT FROM AUTHOR]

Due to the in-situ generation of reactive oxygen species (ROS), sulfate radical-based advanced oxidation processes (SR-AOPs) have emerged for the oxidative degradation of organic contaminants. Developing highly efficient heterogeneous catalysts is of great importance for SR-AOPs. In this work, an urchin-like Co 3 O 4 nanocatalyst with oxygen vacancies (V O) was elaborately fabricated and employed for enhanced peroxymonosulfate (PMS) activation to degrade the high-concentration active dye crystal violet (CV). The obtained sample was characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and N 2 adsorption/desorption isotherms. Characterization results indicated that this unique V O -rich urchin-like Co 3 O 4 nanocatalyst was endowed with a larger surface area and abundant reactive sites for PMS adsorption and activation. The experimental results of CV degradation showed that nearly complete removal of 100 mg L−1 CV could be realized within 30 min of reaction time under neutral conditions at room temperature, and the degradation process followed retarded-first-order kinetics. Electron paramagnetic resonance (EPR) spectra accompanied by quenching experiments of radicals demonstrated that the contribution of ROS to CV degradation followed this sequence: 1O 2 > ▪OH > SO 4 ▪- > O 2 ▪-. The degradation pathways of CV were proposed by a combination of density functional theory (DFT) calculations along with frontier orbit theory while the toxicity of intermediate products was evaluated by quantitative structure-activity relationship (QSAR) prediction. [Display omitted] • Oxygen-vacancy-rich urchin-like Co 3 O 4 was fabricated for PMS activation. • Active radicals were confirmed by radical quenching tests and EPR technology. • Radical 1O 2 dominated crystal violet degradation by a nonfree radical pathway. • The degradation pathways of CV were simulated by DFT calculations. • The toxicity of intermediate products was evaluated by QSAR prediction. [ABSTRACT FROM AUTHOR]

In order to improve the anticorrosive performance of waterborne epoxy (WEP) coating, small amounts of polyaniline (PANI) were blended under ultrasonic irradiation to obtain PANI/WEP composite coatings with high dispersibility of PANI particles. The PANI/WEP composite coatings were characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Their adhesive force level and hardness grade were tested based on the Chinese National Standard GB/T9286-1998 and GB/T6739-1996, respectively. These results indicated that, compared to the pristine WEP coating, the addition of PANI with suitable content could completely fill the micropores or microcracks and remarkably improve the hardness grade of composite coatings. The electrochemical impedance spectra and Tafel polarization curves revealed that the addition of PANI not only could increase the impedance arc, but also could increase the impedance modulus at low frequency. Then, the salt spray tests were employed to observe the anticorrosive performance of PANI/WEP composite coatings. Finally, the enhanced anticorrosive mechanism of WEP coating by the addition of small amounts of PANI was proposed and discussed. The addition of PANI with suitable content could play an important role of physical and chemical barriers to improve the anticorrosive performance of waterborne epoxy coating. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hierarchical Co 3 O 4 @Co 3 O 4 /Fe 3 O 4 yolk-shell nanoreactor was designed and prepared. • The confinement effect and bimetallic cycles were integrated in this nanoreactor. • This nanoreactor could activate PMS for various organic pollutants degradation. • DFT calculations and MD simulations disclosed the confined reaction mechanisms. It is still a challenging task to reasonably design an efficient Co 3 O 4 -based nanoreactor for persulfate activation and accurately disclose the confined reaction mechanism. Herein, we design and prepare a hierarchical Co 3 O 4 @Co 3 O 4 /Fe 3 O 4 yolk-shell nanoreactor (CT@CT/MG). In this yolk-shell structured nanoreactor, a Co 3 O 4 solid sphere is the yolk and a flower-like Co 3 O 4 hollow sphere wrapped by Fe 3 O 4 nanoparticles is the shell. The void between them constitutes a confined space. Various instrumental techniques are used to characterize the structure and compositions of this nanoreactor. Degradation experiments show that CT@CT/MG have powerful capability to activate peroxymonosulfate (PMS) for the degradation and mineralization of various organic pollutants and even their mixture. Radical quenching experiments and EPR results confirm that •OH and SO 4 •− are the dominant reactive oxygen species in the CT@CT/MG-PMS system. Electrochemical measurements indicate that CT@CT/MG have better electron transfer ability and lower charge transfer resistance. In-situ characterization techniques including in-situ FT-IR and in-situ Raman are employed for deep insights into the potential reaction mechanisms. XPS analyses prove that Fe2+ promote the cycling regeneration of the reactive Co2+. MD simulations and DFT calculations disclose the confined reaction mechanisms by the means of comparative investigations in a confined space and under the unrestricted environment. [ABSTRACT FROM AUTHOR]

The main focus of current attempts at sustainable energy development and environmental remediation is on using catalysts to directly transform primary energy (solar, mechanical, and thermal energies) from the surrounding environment into chemical energy. However, the strong charge recombination is a major factor in why the presently available catalysts are not up to par in their catalytic effectiveness. The creation of polarization electric fields has emerged as one of the most successful solutions to this issue. This review focuses on the principles of the piezoelectric effect in ferroelectric, piezoelectric, and pyroelectric materials, the mechanism of piezoelectric catalysis and piezoelectric photocatalysis, and the integration of polarization electric field and semiconductor properties to promote the separation of electron-hole pairs and regulate the charge migration process in the bulk phase. Based on the comparison and classification of different structure types of piezoelectric catalysts and piezoelectric photocatalysts in low dimensions, optimization techniques to improve piezoelectric properties and catalytic activities were introduced and the latest progress of polarization-facilitated piezoelectric catalysis/piezoelectric photocatalysis in the polarization electric field of renewable energy production and environmental remediation was overviewed. Finally, we outlined the significant obstacles and possible alternatives for designing polarization-enhanced strategies that make use of efficient energy harvesting. [Display omitted] • The piezoelectric and piezo-photoelectric effects were summarized and categorized. • Enhancement strategies towards improving polarization electric field were discussed. • The low- dimensional piezoelectric catalysts and piezoelectric photocatalysts were reviewed. • Challenges and prospects of piezoelectric catalyst and piezoelectric photocatalyst were outlined. [ABSTRACT FROM AUTHOR]

In this paper, fast numerical methods are established to solve a class of time distributed-order and Riesz space fractional diffusion-wave equations. We derive new difference schemes by a weighted and shifted Grünwald formula in time and a fractional centered difference formula in space. The unconditional stability and second-order convergence in time, space and distributed-order of the difference schemes are analyzed. In the one-dimensional case, the Gohberg-Semencul formula utilizing a preconditioned Krylov subspace method is developed to solve the Toeplitz linear system derived from the proposed difference scheme. In the two-dimensional case, we also design a global preconditioned conjugate gradient method with a truncated preconditioner to solve the resulting Sylvester matrix equations. We prove that the spectrums of the preconditioned matrices in both cases are clustered around 1, such that the proposed numerical methods with preconditioners converge very quickly. Some numerical experiments are carried out to demonstrate the effectiveness of the proposed difference schemes and show that the performances of the proposed fast solution algorithms are better than other testing methods. [ABSTRACT FROM AUTHOR]

Characterizing electrical breakdown limits of materials is a crucial step in device development. However, methods for repeatable measurements are scarce in two-dimensional materials, where breakdown studies have been limited to destructive methods. This restricts our ability to fully account for variability in local electronic properties induced by surface contaminants and the fabrication process. To tackle this, we implement a two-step deep-learning model to predict the breakdown mechanism and breakdown voltage of monolayer MoS2 devices with varying channel lengths and resistances using current measured in the low-voltage regime as inputs. A deep neural network (DNN) first classifies between Joule and avalanche breakdown mechanisms using partial current traces from 0 to 20 V. Following this, a convolutional long short-term memory network (CLSTM) predicts breakdown voltages of these classified devices based on partial current traces. We test our model with electrical measurements collected using feedback-control of the applied voltage to prevent device destruction, and show that the DNN classifier achieves an accuracy of 79% while the CLSTM model has a 12% error when requiring only 80% of the current trace as inputs. Our results indicate that information encoded in the current behavior far from the breakdown point can be used for breakdown predictions, which will enable non-destructive and rapid material characterization for 2D material device development. [ABSTRACT FROM AUTHOR]

Date plum persimmon (Diospyros lotus L.) is a fruit crop from the Ebenaceae family. Its microorganism-fermented extract (DPEML) was shown to exhibit a hypoglycemic effect in our previous work. Here, we investigated the effects of DPEML fermented by Microbacterium flavum YM18-098 and Lactobacillus plantarum B7 on the high glucose-induced apoptosis of MIN6 cells and explored its potential cell protective mechanisms. DPEML ameliorated the apoptosis of MIN6 cells cultured under high glucose conditions, thereby improving cell viability. DPEML upregulated the Bcl-2/Bax mRNA ratio to obstruct an intrinsic apoptotic pathway and concomitantly downregulated the expression of the apoptosis-linked proteins, AIF, and Cyt-C, in high glucose-induced MIN6 cells. Furthermore, DPEML promoted the insulin secretion of MIN6 cells grown under chronically high-glucose conditions by upregulating Ins mRNA expression. In summary, our study suggested that DPEML is a promising functional food for the development of therapeutics for the treatment of Type 2 diabetes mellitus. Practical applications: We investigated the effects of DPEML fermented by Microbacterium flavum YM18-098 and Lactobacillus plantarum B7 on the high glucose-induced apoptosis of MIN6 cells and explored its potential cell protective mechanisms. DPEML ameliorated the apoptosis of MIN6 cells cultured under high glucose conditions, thereby improving cell viability. DPEML upregulated the Bcl-2/Bax mRNA ratio to obstruct an intrinsic apoptotic pathway and concomitantly downregulated the expression of the apoptosis-linked proteins, AIF and Cyt-C, in high glucose-induced MIN6 cells. Furthermore, DPEML promoted the insulin secretion of MIN6 cells grown under chronically high-glucose conditions by upregulating Ins mRNA expression. We suggested that DPEML is a promising functional food for the development of therapeutics for the treatment of Type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

In this paper, we propose a fast compact implicit integration factor (FcIIF) method with non-uniform time meshes for solving the two-dimensional nonlinear Riesz space-fractional reaction-diffusion equation. The weighted and shifted Grüwald-Letnikov (WSGD) approximation is employed to the spatial discretization of the equation, and a system of nonlinear ordinary differential equations (ODEs) in matrix form is obtained. Since the cIIF method can provide excellent stability properties with good efficiency by decoupling the treatment of the diffusion and reaction terms, a fast cIIF (FcIIF) method with non-uniform time meshes is developed to solve the resultant nonlinear system of ODEs. Compared with the cIIF method, the proposed FcIIF method avoids the direct calculation of dense exponential matrices and requires less computational cost. The stability, accuracy and effectiveness of the proposed method are verified by the linear stability analysis and various numerical experiments. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe 3 O 4 /BiOI p-n heterojunction was fabricated by an in situ anchor technology. • Fe 3 O 4 /BiOI heterojunction was employed for the photocatalytic peroxydisulfate activation. • The degradation of high-concentration Rhodamine B followed the pseudo-first-order kinetics. • The mechanism on the photocatalytic peroxydisulfate activation was proposed and discussed. Combining various advanced oxidation processes has been considered as an emerging approach for degrading organic contaminants, which can overcome the deficiencies of a single one. In this study, the photocatalytic oxidation and persulfate-based oxidation were allied for degrading high-concentration Rhodamine B (RhB). To strengthen this alliance, Fe 3 O 4 /BiOI p-n heterojunctions were constructed by anchoring Fe 3 O 4 nanoparticles onto flower-like BiOI. Various instrumental techniques, including X-ray diffractometer, field emission scanning electron microscope, transmission electron microscope, X-ray photoelectron spectrometer, photoluminescence emission spectroscopy, UV–Vis diffuse reflectance spectrometer, vibrating sample magnetometer and surface area analyzer were used to characterize these heterojunctions. 100 mg·L−1 RhB was utilized as the probing target to appraise the photocatalytic peroxydisulfate activation by Fe 3 O 4 /BiOI heterojunction under visible light illumination. The pseudo-first-order kinetic model could well describe the RhB degradation process. Finally, the mechanism on the photocatalytic peroxydisulfate activation over Fe 3 O 4 /BiOI heterojunction was proposed and discussed. [ABSTRACT FROM AUTHOR]

In this work, the CeO 2 /Al 2 O 3 composites were prepared by in situ growth method and developed as the heterogeneous Fenton-like catalyst for efficiently catalytic degradation of methyl orange (MO). Porous Al 2 O 3 was firstly prepared by an evaporation-sintering method, and then the CeO 2 /Al 2 O 3 composites were constructed by the in situ growth of CeO 2 onto porous Al 2 O 3. The phases and morphologies of the porous Al 2 O 3 and CeO 2 /Al 2 O 3 composites were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and specific surface area and pore size analyzer. The results indicated that the higher amount of the porogenic agent (NH 4 Cl) could make the specific surface area of porous Al 2 O 3 larger and the Fenton-like reaction efficiency of CeO 2 /Al 2 O 3 better. Free radical trapping experiments showed that the singlet oxygen (1O 2) was the main reactive oxygen species responsible for the MO degradation. Finally, the possible mechanism of the Fenton-like reaction catalyzed by CeO 2 /Al 2 O 3 was proposed and discussed. [Display omitted] • Porous alumina was easily prepared by an evaporation-sintering method. • CeO 2 /Al 2 O 3 catalyst was fabricated by the in situ anchor of CeO 2 onto porous Al 2 O 3. • The main reactive oxidative species in CeO 2 /Al 2 O 3 –H 2 O 2 system were singlet oxygen. • The mechanism of MO degradation in CeO 2 /Al 2 O 3 –H 2 O 2 system was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four Co 3 O 4 multi-crystals with specific morphologies were designed and synthesized. • HRTEM technique revealed that these four Co 3 O 4 samples had different exposed facets. • The E ads and electron transfer of exposed facets had potential effect on catalytic efficiency. • The synergy of different exposed facets could promote the activation of PMS. • The degradation pathway was deduced by frontier orbital theory and Fukui function. As a fluoroquinolone antimicrobial agent, ofloxacin (OFX) has been widely used, consequently causing serious damage to the ecological environment. Advanced oxidation processes based on persulfate activation (SR-AOPs) are widely applied to degrade stubborn organic contaminants in wastewater treatment. Co 3 O 4 is being extensively investigated as a promising persulfate catalyst in SR-AOPs. In this work, four Co 3 O 4 polycrystals with specific morphologies were synthesized and used to activate peroxymonosulfate (PMS) for OFX degradation. The obtained samples and corresponding precursors were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and N 2 adsorption/desorption isotherms. Experimental results showed that 30 mg·L-1 OFX could be completely removed in the lamella-like Co 3 O 4 /PMS system within 30 min under ordinary conditions. The underlying degradation mechanism was elaborated by high-resolution TEM (HRTEM) combined with density functional theory (DFT) calculations. Based on quenching experiments and the electron paramagnetic resonance (EPR) technique, sulfate radicals were identified as the dominant reactive oxygen species (ROS) in the lamella-like Co 3 O 4 /PMS system, and superoxide radicals, hydroxyl radicals, and singlet oxygen made minor contributions to the degradation of OFX. Possible degradation pathways were proposed based on DFT calculations and Fukui theory and confirmed by ultrahigh-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UHPLC-QTOF/MS). Furthermore, quantitative structure–activity relationship (QSAR) prediction was used to evaluate the developmental toxicity of the corresponding intermediates. [ABSTRACT FROM AUTHOR]

Abstract By p-type and n-type doping on the electrode edges of V-notched zigzag graphene nano-ribbons (ZGNRs), four V-notched ZGNR-based PN-junctions are designed theoretically. The electronic transport properties of the doped and un-doped V-notched ZGNRs are studied applying non-equilibrium Green's function method combined with the density functional theory. The numerical results show that, the doped systems are less conductive than the un-doped system, because after doping the transition states become localized. To our surprise, the ZGNR-based PN-junctions do not show obvious rectification by purely doping the boron atoms and nitrogen atoms on the edges of two ZGNR electrodes respectively. However, after hydrogenated the doped boron atoms and nitrogen atoms, the ZGNR systems present giant rectifications with the maximum rectification ratios up to 10 6 ∼ 10 7 , which attributed to the vanishing of overlap between left-electrode sub-band and right-electrode sub-band in the negative bias regime after the doped boron and nitrogen atoms being hydrogenated. Due to the same reason, the hydrogenated doping systems also show large negative differential conductance behaviors. Highlights • Four different graphene-nano-ribbon (GNR)-based PN-junctions are designed by doping. • Boron and nitrogen (BN) doped GNR-based junctions show little rectification behavior. • Hydrogenated BN-doped junctions show giant rectification behaviors. • Hydrogenation induces localized transition states as well as rectification behaviors. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Developing a catalyst with high efficiency and recyclability is an important issue for the heterogeneous Fenton-like systems. In this study, magnetic Fe 3 O 4 and reduced graphene oxide (RGO) nanocomposites were prepared by a facile alkaline-thermal precipitation method and employed as a highly effective heterogeneous Fenton-like catalyst for methyl orange (MO) degradation. Characterization of these nanocomposites by XRD, FTIR, Raman, FESEM and TEM revealed that nanoparticles (NPs) of Fe 3 O 4 were tightly anchored on the few-layer RGO sheets. The anchoring of Fe 3 O 4 NPs and the reduction of GO were achieved in one pot without adding any other reducing agents. Based on the measurements of GO surface Zeta potentials, a possible anchoring mechanism of Fe 3 O 4 NPs onto RGO sheets was given. The Fe 3 O 4 /RGO nanocomposites exhibited much higher Fenton-like catalytic efficiency for MO degradation than pure Fe 3 O 4 NPs. This degradation process followed the first-order kinetics model, where k 1 and T complied with the Arrhenius equation with E a of 12.79 kJ/mol and A of 8.20 s−1. Magnetic measurements revealed that Fe 3 O 4 /RGO nanocomposites were ferromagnetic as indicated by the presence of magnetic hysteresis loops. The Fe 3 O 4 /RGO nanocomposites showed good stability and recyclability. Hydroxyl radicals, OH were determined as the dominant oxidative species in Fe 3 O 4 /RGO-H 2 O 2 system and the Fenton-like mechanism for MO degradation in water was proposed and discussed. [ABSTRACT FROM AUTHOR]

Zinc ferrite (ZnFe2O2) photocatalysts with different morphologies (sizes and shapes) were synthesized to explore the effect of morphology on their photocatalytic efficiency. The results obtained using field emission scanning electron microscopy (FESEM) revealed that the obtained samples had the needle-, cube-, granule- and plate-like morphology, labeled as NZFO, CZFO, GZFO and PZFO, respectively. X-ray diffraction (XRD) patterns showed that all the samples had the spinel structure of ZnFe2O4 without any other impurities. The calculated average crystallite size followed the order NZFOGZFO>CZFO>PZFO. The photocatalytic efficiency for the degradation of methyl orange also followed the order NZFO> >GZFO>CZFO>PZFO. The morphology-dependent photocatalytic efficiency of ZnFe2O4 was closely related with its crystallite size and surface area. The smaller the crystallite size was, the larger the surface area was, and the higher the photocatalytic efficiency was. [ABSTRACT FROM AUTHOR]

The development of a catalyst with high catalytic activity was one of the most important issues for the heterogeneous Fenton-like process. In this study, nanocomposites of Fe3O4 anchored onto reduced graphene oxide (RGO) were prepared by a moderate alkaline-thermal precipitation method and developed as highly efficient heterogeneous Fenton-like catalysts. The characterization results indicated that Fe3O4 nanoparticles (NPs) were tightly anchored onto few-layer RGO sheets via a strong interaction. Contrast experiments showed that Fe3O4/RGO nanocomposites had much better Fenton-like catalytic activity than Fe3O4 NPs. The process optimization of methyl orange (MO) discoloration in Fe3O4/RGO-H2O2 system was accomplished by central composite design under response surface methodology. A second-order polynomial model was established to predict the optimal values of MO discoloration and its significance was evaluated by analysis of variance. Three-dimensional response surfaces for the interaction between two variables were constructed. Based on the model prediction, the optimum conditions for MO discoloration in Fe3O4/RGO-H2O2 system were 2.9 for solution pH, 16.5 mM H2O2 concentration, 2.5 g/L catalyst dosage and 33.5 min of reaction time, with the maximum predicted value for MO discoloration ratio of 99.98%. [ABSTRACT FROM AUTHOR]

[Display omitted] • A Fe 3 O 4 @HNTs nanoreactor was designed to expedite Fenton-like reactions. • Fe 3 O 4 @HNTs exhibited much higher Fenton-like catalysis efficiency than Fe 3 O 4. • •OH and 1O 2 were determined as the main reactive radicals. • A novel space confinement strategy was developed for Fenton-like reactions. Heterogeneous Fenton-like reactions occurring in the confined space of a nanoreactor exhibited much higher efficiency than those in bulk solution. In this work, a Fenton-like nanoreactor was designed by selectively filling Fe 3 O 4 nanoparticles into the lumen of halloysite. This nanoreactor was fabricated by vacuum impregnation method and characterized by various instrumental techniques. Experimental results indicated that, compared with Fe 3 O 4 nanoparticles, this nanoreactor could remarkably expedite the degradation of 50 mg·L-1 methyl orange in presence of H 2 O 2. •OH and 1O 2 were detected as the main reactive radicals. A space confinement mechanism was proposed to expound the enhanced Fenton-like efficiency and radicals formation pathways. [ABSTRACT FROM AUTHOR]

Traffic congestion incurs long delay in travel time, which seriously affects our daily travel experiences. Exploring why traffic congestion occurs is significantly important to effectively address the problem of traffic congestion and improve user experience. Traditional approaches to mine the congestion causes depend on human efforts, which is time consuming and cost-intensive. Hence, we aim at discovering the known and unknown causes of traffic congestion in a systematic way. However, to achieve it, there are three challenges: (1) traffic congestion is affected by several factors with complex spatio-temporal relations; (2) there are a few samples of congestion data with known causes due to the limitation of human label; (3) more unknown congestion causes are unexplored since several factors contribute to traffic congestion. To address above challenges, we design a congestion cause discovery system consisting of two modules: (1) congestion feature extraction module, which extracts the important features distinguishing between different causes of congestion; and (2) congestion cause discovery module, which designs a deep semi-supervised learning based framework to discover the causes of traffic congestion with limited labeled data. Specifically, in pre-training stage, it first leverages a few labeled data as prior knowledge to pre-train the model. Then, in clustering stage, we propose two different clustering methods to discover the congestion causes. For the first clustering method, we extend the classic deep embedded clustering model to produce clusters via soft assignment. For the second one, we iteratively use k-means to group the latent features extracted from the pre-trained model, and use the cluster results as pseudo-labels to fine-tune the network. Extensive experiments show that the performance of our methods is superior to the state-of-the-art baselines, which demonstrates the effectiveness of the proposed cause discovery system. Additionally, our system is deployed and used in the practical production environment at Amap. [ABSTRACT FROM AUTHOR]

Background: Metastasis is the major cause of morbidity and mortality in patients with epithelial ovarian cancer (EOC), however the mechanisms that underline this process are poorly understood. Collagen triple helix repeat containing-1 (CTHRC1) is a 28-kDa secreted protein reported to be involved in vascular remodeling, bone formation and morphogenesis. This study aimed to investigate the role of CTHRC1 in promoting the metastasis of EOC and to elucidate the underlying molecular mechanisms. Methods: The biologic functions of CTHRC1 in metastasis were validated both in vivo and in vitro experiments. The phosphor-antibody microarray analysis and Co-immunoprecipitation were performed to detect and identify the integrin β3/FAK signaling pathway that mediated the function of CTHRC1. Seventy two EOC samples were analyzed for association between CTHRC1/integrin β3 expression and patient clinicopathological features. Results: We demonstrated that CTHRC1 enhances the biological behavior of EOC including cell migration, invasion, as well as its adhesion capability to cell-extracellular matrix in vitro. Additionally, CTHRC1 promoted metastatic spread of EOC cells in an i.p. ovarian xenograft model and this phenotype was primarily ascribed to the activation of integrin/FAK signaling. Mechanistically, we determined that FAK were phosphorylated on Tyr397, and were activated by integrin β3, which is important for the CTHRC1-mediated migratory and invasive ability of EOC cells in vitro and i.p. metastasis. In addition, we found that attenuated CTHRC1/integrin β3 expression predicted a poor prognostic phenotype and advanced clinical stage of EOC. Conclusions: Our results suggest that CTHRC1, a newly identified regulator of i.p. metastasis through activation of integrin β3/FAK signaling in EOC, may represent a potential therapeutic target for ovarian cancer. [ABSTRACT FROM AUTHOR]

Necrotizing soft tissue infections (NSTIs) are aggressive infections requiring prompt diagnosis and extensive surgical debridement. Traditionally, patients undergo mandatory re-exploration to ensure adequacy of source control. The purpose of this study is to determine if re-exploration in the operating room is mandatory for all patients with NSTIs. An eight-year retrospective analysis of adult patients with NSTIs was performed comparing two groups: mandatory operative re-exploration versus operative re-exploration based on clinical examination findings. Outcomes measured included mortality, number of debridements, and length of stay (LOS). Twenty-two per cent of patients underwent a mandatory re-exploration. These patients were older, had a higher incidence of diabetes, and a longer duration of symptoms. There were no significant differences between groups with regard to the physical examination, severity of sepsis, time to repeat debridements, or in-hospital mortality, whereas LOS and the total number of debridements were increased in mandatory re-exploration. Bacteremia and septic shock were predictive of the need for further debridement in patients in the operative re-exploration based on clinical examination findings group. Mandatory re-exploration after initial debridement may not be necessary in all patients with NSTIs. Instead, bedside wound checks may be a safe strategy to determine the need for further operative debridement. [ABSTRACT FROM AUTHOR]

[Display omitted] • Six ZnO nanocrystals with different morphologies were designed and synthesized. • O 2 –, OH, and holes were the main reactive radicals in the photocatalytic process. • The polar crystal plane could facilitate the separation of charge carriers. • The adsorption and distortion energies for O 2 were higher than those for H 2 O. Zinc oxide (ZnO) has been regarded as a promising photocatalytic candidate for the purification of wastewaters containing organic contaminants. In this study, six ZnO nanocrystals with the shapes of granule, flake, rod, porous flake, nanosheet-assembled flower, and nanorod-assembled flower were designed and synthesized to investigate the relationship between their photocatalytic activities and morphological features. All these different morphological samples had high-degree of crystallization and belonged to the hexagonal wurtzite structure of ZnO. The morphology had little effect on the light absorption threshold and band gap of these samples, but showed great effect on their adsorption performance, photocatalytic activity, and separation efficiency of photogenerated electrons and holes. The main reactive radicals generated during the photocatalytic process were O 2 –, OH, and holes. The theoretical calculations revealed that the polar crystal plane could facilitate the separation of charge carriers. The adsorption and distortion energies for O 2 adsorbed onto different crystal planes were found to be much higher than those for H 2 O. These findings theoretically confirmed why O 2 – was the dominant group of reactive radicals. [ABSTRACT FROM AUTHOR]

BiOXxY1-x (X, Y = Cl, Br, and I) solid solutions have been regarded as promising photocatalysts attributed to their unique layered structure, tunable band structure, and chemical and optical stability. In this study, BiOBrxI1-x nanoplate solid solutions with a high exposure of {001} crystal facets were prepared by a facile alcoholysis method at room temperature and atmospheric pressure. X-ray diffraction (XRD) peaks exhibited a slight shift to lower diffraction angle with the increase of I content in BiOBrxI1-x samples, which resulted in a gradual increase in their cell parameters. Field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM) images revealed that BiOBrxI1-x samples exhibited 2D plate-like structure with the in-plane wrinkles. The regular changes in optical absorption threshold and Eg value seen in UV-vis diffuse reflectance spectra (UV-vis DRS) indicated that the optical absorption property and band structure could be modulated by the formation of BiOBrxI1-x solid solutions. The photocatalytic degradation of active dye Rhodamine B (RhB) over BiOBrxI1-x solid solutions showed that BiOBr0.75I0.25 had the best photocatalytic activity. The RhB photodegradation processes followed a pseudo-first-order kinetic model. The synergistic effect of structural factors (including amount of exposed {001} facets, interlayer spacing of (001) plane, and energy-level position of the valence band) determined the photocatalytic performance of BiOBrxI1-x solid solutions. [ABSTRACT FROM AUTHOR]

In this paper, we study a path finding strategy based on random walk in which we allow multiple particles to set out from different but neighboring sources to their common destination. Three path finding models, the single-particle-form-one-source, the multiple-particles-from-one-source, and the last multiple-particles-form-multiple-sources (MSMP) are described. Then we apply the three models to different simulation networks. The experiment results show that the MSMP schema can decrease the path finding cost. Furthermore, we propose an absorption strategy to deal with the additional Brownian particles in networks. The experiment results on BA networks show that the absorption strategy can increase the probability of a successful path finding. In the end, we find he path found out by above methods may be the shortest theoretically, but may not be optimal in the practical application. To overcome this, we put forward a method to calculate the optimal path based on arrival reliability and verify its correctness by enumeration. [ABSTRACT FROM AUTHOR]

Due to the difficult separation of superfine schorl powder (SSP) from solution after being used, millimetre-scale porous schorl ceramisite (PSC) was obtained through solid-phase sintering method and used as a heterogeneous catalyst for Fenton-like discoloration of organic dyes. SSP and PSC were characterized by X-ray diffraction, Fourier transform infrared spectroscopy and field emission scanning electron microscopy. The results demonstrated that both SSP and PSC were mainly composed of schorl and there existed large amounts of micropores on the surface of PSC. A series of control experiments indicated that PSC exhibited higher Fenton-like catalytic activity than SSP. Methylene blue (MB) discoloration in both PSC-H2O2 and SSP-H2O2 systems followed pseudo-firstorder kinetics and the reaction rate constant k1 obtained in PSC-H2O2 system was 3.23 times as large as the one in SSP-H2O2 system. Then, the process optimization of MB discoloration in heterogeneous Fenton-like reaction catalyzed by PSC was operated by central composite design under response surface methodology. Based on the model prediction, the optimum conditions for MB discoloration in this system were determined. [ABSTRACT FROM AUTHOR]

We performed micromagnetic simulations to investigate the exact underlying topological mechanism of skyrmion generation by blowing magnetic chiral stripe domains with a spin current generated by the spin Hall effect. This analysis of the topological dynamics reveals that the generation of a magnetic skyrmion is typically mediated by the creation and annihilation of an antiskyrmion. The threshold current density needed to generate persistent skyrmions depends on the damping constant, perpendicular magnetic field, and size of the sample. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe 3 O 4 /BiOI p-n heterojunction was designed as photocatalytic persulfate activator. • The p-n junction formation expedited the degradation of high-concentration dye. • The singlet oxygen (1O 2) was determined as the primary reactive oxygen species. • A new heterojunction engineered strategy was developed for persulfate activation. The coupling of photocatalysis with persulfate-based oxidation has been regarded as a promising strategy to increase the overall reaction efficiency for organic pollutants removal. Designing an appropriate semiconductor heterojunction is a crucial prerequisite for this strategy. In this work, a p-n heterojunction was fabricated by combining p-type semiconductor BiOI with n-type Fe 3 O 4. A facile in-situ precipitation method was developed to anchor Fe 3 O 4 nanoparticles onto flower-like BiOI. Various instrumental techniques were employed to characterize this heterojunction. The p-n junction formation could remarkably expedite the degradation of high-concentration Rhodamine B (RhB, 100 mg L−1) via peroxydisulfate activation under visible light illumination. The high activity, good stability and magnetic nature of this heterojunction would pave the way for practical applications. [ABSTRACT FROM AUTHOR]

Acid-induced gelation properties of heated whey protein isolate (WPI) and carboxymethylcellulose (CMC) soluble complex were investigated as a function of CMC molecular weight (270, 680, and 750 kDa) and concentrations (0% to 0.125%). Heated WPI-CMC soluble complex with 6% protein was made by heating biopolymers together at pH 7.0 and 85 °C for 30 min and diluted to 5% protein before acid-induced gelation. Acid-induced gel formed from heated WPI-CMC complexes exhibited increased hardness and decreased water holding capacity with increasing CMC concentrations but gel strength decreased at higher CMC content. The highest gel strength was observed with CMC 750 k at 0.05%. Gels with low CMC concentration showed homogenous microstructure which was independent of CMC molecular weight, while increasing CMC concentration led to microphase separation with higher CMC molecular weight showing more extensive phase separation. When heated WPI-CMC complexes were prepared at 9% protein the acid gels showed improved gel hardness and water holding capacity, which was supported by the more interconnected protein network with less porosity when compared to complexes heated at 6% protein. It is concluded that protein concentration and biopolymer ratio during complex formation are the major factors affecting gel properties while the effect of CMC molecular weight was less significant. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) used in this work was obtained by heating dicyandiamide and melamine, respectively, at different temperatures. The differences of g-C3N4 derived from different precursors in phase composition, functional group, surface morphology, microstructure, surface property, band gap and specific surface area were investigated by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-visible diffuse reflection spectroscopy and BET surface area analyzer, respectively. The photocatalytic discoloration of an active cationic dye, Methylene Blue (MB) under visible-light irradiation indicated that g-C3N4 derived from melamine at 500°C (CN-M500) had higher adsorption capacity and better photocatalytic activity than that from dicyandiamide at 500°C (CN-D500), which was attributed to the larger surface area of CN-M500. MB discoloration ratio over CN-M500 was affected by initial MB concentration and photocatalyst dosage. After 120 min reaction time, the blue color of MB solution disappeared completely. Subsequently, based on the measurement of the surface Zeta potentials of CN-M500 at different pHs, an active anionic dye, Methyl Orange (MO) was selected as the contrastive target pollutant with MB to reveal the synergic effect between adsorption and photocatalysis. Finally, the photocatalytic mechanism was discussed. [ABSTRACT FROM AUTHOR]

We reported that atomically dispersed Pd on graphene can be fabricated using the atomic layer deposition technique. Aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure spectroscopy both confirmed that isolated Pd single atoms dominantly existed on the graphene support. In selective hydrogenation of 1,3-butadiene, the single-atom Pd1/graphene catalyst showed about 100% butenes selectivity at 95% conversion at a mild reaction condition of about 50 °C, which is likely due to the changes of 1,3-butadiene adsorption mode and enhanced steric effect on the isolated Pd atoms. More importantly, excellent durability against deactivation via either aggregation of metal atoms or carbonaceous deposits during a total 100 h of reaction time on stream was achieved. Therefore, the single-atom catalysts may open up more opportunities to optimize the activity, selectivity, and durability in selective hydrogenation reactions. [ABSTRACT FROM AUTHOR]

In the paper, it proposes an optimization framework addressing fairness issues for opportunity routing in wireless mesh networks, where we use network coding to ease the routing problem. We propose a distributed heuristic algorithm in the case when scheduling is determined by MAC, and discuss the suitability of our algorithm through simulations. It is found that in most situations our algorithm has better performances than the single-path algorithm and the classical network coding which is based opportunity algorithm MORE. [ABSTRACT FROM AUTHOR]

Compared with single path routing protocols, multipath routing protocols have many advantages in loading balancing, improving reliability and fault tolerance. A lot of multipath routing protocols are designed by expanding single path routing protocols, just like DSR or AODV. However, these protocols are not suitable for the network of large scale and high density as too many control messages will lead to the broadcast storm problem. This paper presented a novel multipath routing protocol called ZMG (zoning-based multipath geographic routing protocol) to construct maximally node-disjoint multipath. In the proposed scheme, each node got his location information from GPS, discovered multiple paths and forwarded data packets by combining interior region forwarding mode and boundary forwarding mode. Simulation results show that ZMG not only has less control messages, but also can find maximally node-disjoint paths, which increases the packet delivery ratio. [ABSTRACT FROM AUTHOR]

The liver bile acids transporter sodium taurocholate cotransporting polypeptide (NTCP) is responsible for the majority of sodium- dependent bile salts uptake by hepatocytes. NTCP also functions as a cellular receptor for viral entry of hepatitis B virus (HBV) and hepatitis D virus (HDV) through a specific interaction between NTCP and the pre-S1 domain of HBV large envelope protein. However, it remains unknown if these two functions of NTCP are independent or if they interfere with each other. Here we show that binding of the pre-S1 domain to human NTCP blocks taurocholate uptake by the receptor; conversely, some bile acid substrates of NTCP inhibit HBV and HDV entry. Mutations of NTCP residues critical for bile salts binding severely impair viral infection by HDV and HBV; to a lesser extent, the residues important for sodium binding also inhibit viral infection. The mutation S267F, corresponding to a single nucleotide polymorphism (SNP) found in about 9% of the East Asian population, renders NTCP without either taurocholate transporting activity or the ability to support HBV or HDV infection in cell culture. These results demonstrate that molecular determinants critical for HBV and HDV entry overlap with that for bile salts uptake by NTCP, indicating that viral infection may interfere with the normal function of NTCP, and bile acids and their derivatives hold the potential for further development into antiviral drugs. [ABSTRACT FROM AUTHOR]

The liver bile acids transporter sodium taurocholate cotransporting polypeptide (NTCP) is responsible for the majority of sodium- dependent bile salts uptake by hepatocytes. NTCP also functions as a cellular receptor for viral entry of hepatitis B virus (HBV) and hepatitis D virus (HDV) through a specific interaction between NTCP and the pre-S1 domain of HBV large envelope protein. However, it remains unknown if these two functions of NTCP are independent or if they interfere with each other. Here we show that binding of the pre-S1 domain to human NTCP blocks taurocholate uptake by the receptor; conversely, some bile acid substrates of NTCP inhibit HBV and HDV entry. Mutations of NTCP residues critical for bile salts binding severely impair viral infection by HDV and HBV; to a lesser extent, the residues important for sodium binding also inhibit viral infection. The mutation S267F, corresponding to a single nucleotide polymorphism (SNP) found in about 9% of the East Asian population, renders NTCP without either taurocholate transporting activity or the ability to support HBV or HDV infection in cell culture. These results demonstrate that molecular determinants critical for HBV and HDV entry overlap with that for bile salts uptake by NTCP, indicating that viral infection may interfere with the normal function of NTCP, and bile acids and their derivatives hold the potential for further development into antiviral drugs. IMPORTANCE Human hepatitis B virus (HBV) and its satellite virus, hepatitis D virus (HDV), are important human pathogens. Available therapeutics against HBV are limited, and there is no drug that is clinically available for HDV infection. A liver bile acids transporter (sodium taurocholate cotransporting polypeptide [NTCP]) critical for maintaining homeostasis of bile acids serves as a functional receptor for HBV and HDV. We report here that the NTCP-binding lipopeptide that originates from the first 47 amino acids of the pre-S1 domain of the HBV L protein blocks taurocholate transport. Some bile salts dose dependently inhibit HBV and HDV infection mediated by NTCP; molecular determinants of NTCP critical for HBV and HDV entry overlap with that for bile acids transport. This work advances our understanding of NTCP-mediated HBV and HDV infection in relation to NTCP's physiological function. Our results also suggest that bile acids or their derivatives hold potential for development into novel drugs against HBV and HDV infection. [ABSTRACT FROM AUTHOR]

The kinetics and optimization of the decoloration of an active commercial dye, argazol blue BFBR (ABB), by a heterogeneous Fenton-like reaction catalyzed by natural schorl were investigated in this study. The kinetic investigations revealed that the first-order kinetic model was more favorable to describe the decoloration of ABB under different reaction conditions than the second-order and Behnajady-Modirshahla-Ghanbery models. The relationship between the reaction rate constant k and reaction temperature T followed the Arrhenius Equation, with an apparent activation energy Ea of 51.31 kJ⋅mol-1. The central composite design under the response surface methodology was employed for the experimental design and optimization of the ABB decoloration process. The significance of a second order polynomial model for predicting the optimal values of ABB decoloration was evaluated by the analysis of variance and 3D response surface plots for the interactions between the two variables were constructed. Then, the optimum conditions were determined. [ABSTRACT FROM AUTHOR]

Human hepatitis B virus (HBV) and its satellite virus, hepatitis D virus (HDV), primarily infect humans, chimpanzees, or tree shrews (Tupaia belangeri). Viral infections in other species are known to be mainly restricted at the entry level since viral repli-cation can be achieved in the cells by transfection of the viral genome. Sodium taurocholate cotransporting polypeptide (NTCP) is a functional receptor for HBV and HDV, and amino acids 157 to 165 of NTCP are critical for viral entry and likely limit viral infection of macaques. However, the molecular determinants for viral entry restriction in mouse NTCP (mNTCP) remain un-clear. In this study, mNTCP was found to be unable to support either HBV or HDV infection, although it can bind to pre-Sl of HBV L protein and is functional in transporting substrate taurocholate; comprehensive swapping and point mutations of hu-man NTCP (hNTCP) and mNTCP revealed molecular determinants restricting mNTCP for viral entry of HBV and HDV. Re-markably, when mNTCP residues 84 to 87 were substituted by human counterparts, mNTCP can effectively support viral infec-tions. In addition, a number of cell lines, regardless of their species or tissue origin, supported HDV infection when transfected with hNTCP or mNTCP with residues 84 to 87 replaced by human counterparts, highlighting the central role of NTCP for viral infections mediated by HBV envelope proteins. These studies advance our understanding of NTCP-mediated viral entry of HBV and HDV and have important implications for developing the mouse model for their infections. [ABSTRACT FROM AUTHOR]

[Display omitted] • BiOCl 0.5 Br 0.5 nanosheets were in situ anchored onto schorl's surface. • BiOCl 0.5 Br 0.5 nanosheets exhibited highly exposed {0 0 1} crystal planes. • Schorl could enhance the photocatalytic efficiency of BiOCl 0.5 Br 0.5 nanosheets. • A new strategy was put forward to enhance photocatalytic efficiency. A facile ultrasound-assisted alcoholysis method was developed to in situ anchor BiOCl 0.5 Br 0.5 (BOCB) nanosheets onto the surface of natural schorl particulates. X-ray diffraction peak intensity ratio of (0 0 1) to (1 0 2) of BOCB indicated the preferentially exposed {0 0 1} crystal planes. The visible-light-driven photocatalytic degradation rate of RhB over BOCB/schorl composite was higher than that over BOCB. The lower photoluminescence emission intensity revealed that schorl could effectively enhance the separation of photogenerated electron-hole pairs of BOCB, which might be caused by the synergy between the external polarization electric field of schorl and the internal polarization electric field of BOCB. This study provides a new approach for developing the polarization electric field assisted strategies for the enhancement of photocatalytic efficiency. [ABSTRACT FROM AUTHOR]

• A multidelay implicit integration factor (MIIF) method is constructed for nonlinear fractional multidelay reaction diffusion equations. • Compared with traditional BDF and CN schemes, the MIIF scheme can obtain smaller temporal error and more regular convergence order. • Fast Krylov subspace methods are developed to calculate the actions of the Toeplitz matrix exponentials in MIIF. In this article, a fast and efficient numerical method is constructed for solving nonlinear space-fractional multidelay reaction-diffusion equations. Firstly, we spatially discretize the equation using the weighted and shifted Grünwald–Letnikov difference (WSGD) formula. As a result, a nonlinear system of ordinary differential equations (ODEs) is obtained. Then, based on the fact that the implicit integration factor (IIF) method is an effective time-stepping scheme with good stability properties, we develop a multidelay IIF (MIIF) method to deal with the resulting ODE system. Compared with traditional numerical schemes, such as the backward differential formula (BDF) and the Crank–Nicolson scheme (CN), the proposed MIIF scheme has two main advantages: (1) MIIF can achieve high-order accuracy in time; (2) the temporal errors are smaller and the convergence orders observed with MIIF are more regular. In addition, in order to overcome the computational challenges, we propose some Krylov subspace methods to calculate the actions of the Toeplitz matrix exponentials in MIIF. Finally, numerical examples are presented to confirm the accuracy of the MIIF scheme and to demonstrate the considerable computational advantages of the proposed fast solving algorithms. [ABSTRACT FROM AUTHOR]

Primary Tupaia hepatocytes (PTHs) are susceptible to woolly monkey hepatitis B virus (WMHBV) infection, but the identity of the cellular receptor(s) mediating WMHBV infection of PTHs remains unclear. Recently, sodium taurocholate cotransporting polypeptide (NTCP) was identified as a functional receptor for human hepatitis B virus (HBV) infection of primary human and Tupaia hepatocytes. In this study, a synthetic pre-Sl peptide from WMHBV was found to bind specifically to cells expressing Tupaia NTCP (tsNTCP) and it efficiently blocked WMHBV entry into PTHs; silencing of tsNTCP in PTHs significantly inhibited WMHBV infection. Ectopic expression of tsNTCP rendered HepG2 cells susceptible to WMHBV infection. These data demonstrate that tsNTCP is a functional receptor for WMHBV infection of PTHs. The result also indicates that NTCP's orthologs likely act as a common cellular receptor for all known primate hepadnaviruses. [ABSTRACT FROM AUTHOR]

It is essential to predict crowd flow precisely in a city, which is practically partitioned into irregular regions based on road networks and functionality. However, prior works mainly focus on grid-based crowd flow prediction, where a city is divided into many regular grids. Although Convolutional Neural Netwok (CNN) is powerful to capture spatial dependence from grid-based Euclidean data, it fails to tackle non-Euclidean data, which reflect the correlations among irregular regions. Besides, prior works fail to jointly capture the hierarchical spatio-temporal dependence from both regular and irregular regions. Finally, the correlations among regions are time-varying and functionality-related. However, the combination of dynamic and semantic attributes of regions are ignored by related works. To address the above challenges, in this article, we propose a novel model to tackle the flow prediction task for irregular regions. First, we employ CNN and Graph Neural Network (GNN) to capture micro and macro spatial dependence among grid-based regions and irregular regions, respectively. Further, we think highly of the dynamic inter-region correlations and propose a location-aware and time-aware graph attention mechanism named Semantic Graph Attention Network (Semantic-GAT), based on dynamic node attribute embedding and multi-view graph reconstruction. Extensive experimental results based on two real-life datasets demonstrate that our model outperforms 10 baselines by reducing the prediction error around 8%. [ABSTRACT FROM AUTHOR]

Room-temperature phosphorescence (RTP) turn-on assay of heparin with tunable sensitivity and detection window was demonstrated on the basis of the target induced self-assembly of polyethyleneimine capped Mn-doped ZnS (PEI-Mn-ZnS) QDs. The proposed method can cover the whole therapeutic dosing concentration range in postoperation and long-term therapy (0.2–1.2 U/mL, 1.7–10 μM) and cardiovascular surgery (2–8 U/mL, 17–67 μM) in 10 mM Tris–HCl (pH 7.4) buffer and can be applied for heparin determination in 100-fold diluted human serum samples. The tunable sensitivity and detection window was ascribed to the tunable particle size and ligand loading amount of PEI-Mn-ZnS QD arising from the chain length (or molecule weight) and feed amount of PEI. The chain length of PEI exhibited significant effect on the particle size and ligand loading amount and ultimately had important influence on both the sensitivity and detection window. The feeding amount of PEI, however, greatly affected the ligand loading amount alone and, in turn, affected only the detection window. [ABSTRACT FROM AUTHOR]

Abstract: The existence of ‘electrostatic poles’ on the schorl surface encouraged us to apply schorl for a TiO2 support. TiO2/schorl composite photocatalyst was prepared and characterized by XRD, SEM and UV/DRS, and their photocatalytic activity was evaluated by discoloration of acid fuchsine (AF). The results indicated that TiO2 existed in the form of anatase and was well deposited and enwrapped on the schorl surface. The absorption edge of TiO2/schorl exhibited a slight red shift in the UV/DRS spectra, compared with that of pure TiO2. The photocatalytic activity of TiO2/schorl for AF discoloration was higher than that of pure TiO2. The AF discoloration ratio approached 100% after irradiation time of 12h. The optimum photocatalyst was found to be that containing 4.76wt.% of schorl and sintered at 550°C. The reaction followed pseudo-first-order kinetics, discussed by the Langmuir–Hinshelwood model. Hypotheses were proposed to interpret the mechanism for the enhanced photocatalytic activity of TiO2/schorl. [Copyright &y& Elsevier]

To explore the relationship between the structure of the ligands and the luminescent properties of the lanthanide complexes, a series of lanthanide nitrate complexes with two novel structurally related multipodal ligands, 1,3-bis{[(2'-(2-picolylaminoformyl))phenoxyl]methyl}benzene (LI) and 1,2-bis{[(2'-(2-picolylaminoformyl))phenoxyl]methyl}benzene (LII), have been synthesized and characterized by elemental analysis, infrared spectra and molar conductivity measurements. At the same time, the luminescent properties of the Eu(III) and Tb(III) nitrate complexes in solid state and the Tb (III) nitrate complexes in solvents were investigated at room temperature. Under the excitation of UV light, these complexes exhibited characteristic emissions of central metal ions. The lowest triplet state energy levels T1 of these ligands both match better to the lowest resonance energy level of Tb (III) than to Eu(III) ion. The influence of the structure of the ligands on the luminescent intensity of the complexes was also discussed. [ABSTRACT FROM AUTHOR]

Mineral-catalyzed Fenton-like system has been found to be effective for the discoloration of dyeing wastewater. In our present study, schorl has been successfully developed as a novel heterogeneous catalyst for discoloration of an active commercial dye, Argazol blue (BF-BR), in an aqueous solution. Through a number of batch discoloration experiments under various conditions, it was found that the reactivity of the system increased by, respectively, increasing schorl dosage, temperature, hydrogen peroxide starting concentration and by decreasing the pH. At the condition of pH 2, T =55°C, [BF-BR]0 =200mg/L, [H2O2]0 =48.5mmol/L and schorl dosage=10g/L, 100% of discoloration ratio can be achieved in less than 4min, and 72% of total organic carbon (TOC) can be removed in less than 200min. The reaction kinetics analysis shows that the discoloration of BF-BR follows the first-order kinetics. The schorl samples after BF-BR discoloration was tested by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Scanning electron microscope (SEM) and the results rule out the possibility of formation of new solid phases during BF-BR discoloration. The content of Fe ion leaching in the solution was also measured using inductively coupling plasma-atomic emission spectra (ICP-AES). A mechanism proposed herein indicates adsorption and Fenton-like reaction (heterogeneous and homogeneous) are responsible for the discoloration of BF-BR. [Copyright &y& Elsevier]

Abstract: Multi-component sorption studies were carried out for attenuation of divalent heavy metal cations (Pb2+, Cu2+ and Zn2+) by a low-cost mineral adsorbent from the aqueous solution. Kinetic and equilibrium batch-type sorption experiments were conducted under variable conditions for multi-component using low-grade (<12%P2O5) phosphate rock. Percentage of multiple heavy metal species removal increases with decreasing initial metals concentration and particle size. The equilibrium data were well described to a lesser extent by Freundlich model but Langmuir model seemed to be more appropriate with the fixation capacity obtained at room temperature for Pb2+, Cu2+ and Zn2+ was 227.2, 769.2 and 666.6μmolg−1, respectively. Two simple kinetic models were tested to investigate the adsorption mechanism. Rate constants have been found nearly constant at all metal concentrations for first order. The comparison of adsorption capacity of low-grade phosphate rock decreases in multi-component system as compared to single component due to ionic interactions. X-ray powder diffraction (XRPD) technique was used to ascertain the formation of new metal phases followed by surface complexation. Used adsorbents have been converted into a value added product by utilizing innovative Zero-waste concept to solve the used adsorbents disposal problem and thus protecting the environment. [Copyright &y& Elsevier]

A biopolymer containing metal complex, silica-supported alginic acid–amino acid (l-alanine, l-glutamic acid, l-serine or l-lysine)–Pt complex, SiO2–AA–aa–Pt (SiO2–AA–ala–Pt, SiO2–AA–glu–Pt, SiO2–AA–ser–Pt, SiO2–AA–lys–Pt) has been prepared and found to be able to catalyze the asymmetric hydrogenation of furfuryl alcohol to give (S)-(+)-tetrahydrofurfuryl alcohol at 30 °C and under 1 atmH2. Among of them, SiO2–AA–glu–Pt complex catalyst is most effective for this asymmetric reaction and 84.4% product yield and 98.3% ee optical yield can be obtained, respectively. This catalyst can be reused several times without large change in the optical catalytic activity. [Copyright &y& Elsevier]

Due to the edge states of zigzag graphene nanoribbon (ZGNR), heterojunctions of p- and n-type doped ZGNRs with either high rectification ratios or high spin-filter efficiencies are constructed. Four ZGNR-based heterojunctions are designed theoretically by replacing the edge carbon atoms of two ZGNR electrodes with boron atoms and nitrogen atoms, respectively. The electron-transport properties and the spin-transport properties are studied by applying non-equilibrium Green's function method combined with first principles calculations. The numerical results show that, such heterojunctions show 100% spin-filter efficiencies in the lower negative bias regime. This excellent spin-filter behavior originates from the localized spin-up sub-bands that lie on the Fermi level of boron-doped electrode and lead to a destructive interference of electrons in the scattering region, thereby preventing the spin-up electrons from entering the electrode and leading to a near-zero spin-up current in lower bias regime. When the dopant boron and nitrogen atoms are hydrogenated, the 100% spin-filter efficiency disappears, but the rectification ratio up to 106 is obtained. This amazing rectification ratio results from the vanishing overlap of conduction bands of the two electrodes for both spin-up and spin-down sub-bands when the absolute value of the negative bias is greater than 0.4 V. [ABSTRACT FROM AUTHOR]

This paper proposed a cross-layer mobility management scheme for 6LoWPAN wireless sensor networks. It created the architecture for 6LoWPAN wireless sensor networks and presented the cross-layer mobility management algorithm based on the architecture. In the algorithm, the handover in the network layer (L3) and the one in the link layer (L2) were performed synchronously. A node needed neither the care-of address configuration nor the participation in the handover process in L3. Moreover, a node could perform the fast handover in L2 without scanning all the channels. Therefore, it reduces the handover delay, packet loss and handover cost. [ABSTRACT FROM AUTHOR]

This paper proposed a mobile protocol for IPv6 -based urban vehicular networks. The protocol created the urban vehicular network architecture. In the protocol, when a vehicle joint an urban vehicular network, it acquired its home address. During the mobility process, a vehicle was always identified by its home address and did not need to be configured with a care-of address, so the care-of address configuration cost and delay were avoided. As a result, it reduced the mobility handover cost and delay. The protocol did not involve a vehicle in the mobility handover process, so it avoided the extra mobility handover cost and delay caused by the packet loss due to a vehicle's high speed. The simulation data show that the protocol has better performance. [ABSTRACT FROM AUTHOR]