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This paper presents a rolling optimization algorithm for minimizing total vehicle delay for real-time traffic signal control in urban road networks, where the vehicle delay minimization problem is formulated as a quadratically-constrained quadratic programming problem, which is NP-hard. The programming problem is relaxed and resolved using the rolling optimization algorithm in a distributed manner. In particular, we introduce network partition to a large-scale urban road network and then present a regional rolling optimization algorithm to eliminate the low efficiency caused by the large number of decision variables. Numerical experiments are performed on one of Beijing's district road networks to validate the efficiency of the proposed method in benchmark against several typical techniques.

Emerging evidence has suggested that miRNAs are important regulators of intestinal I/R injury, but their function in this context remains elusive. To evaluate the role of miR-26b-5p in intestinal I/R injury. We utilized in vivo murine models of intestinal I/R and in vitro Mode-K cell-based models of oxygen and glucose deprivation/reperfusion (OGD/R) to examine the function of miR-26b-5p in intestinal I/R injury. The expression of miR-26b-5p in intestinal mucosa and Mode-K cell was detected by RT-PCR. HE staining and Chiu’s score were used to evaluate intestinal mucosa injury severity. Apoptosis was detected by TUNEL stain, flow cytometry, and western blot. TargetScan and StarBase prediction algorithms were applied to predict putative target genes of miR-26b-5p and validated by luciferase reporter analyses. We found that the expression of miR-26b-5p in intestinal mucosa was markedly decreased during I/R injury. We additionally found miR-26b-5p overexpression to markedly disrupt intestinal I/R- or OGD/R-induced injury in vivo and in vitro, whereas inhibiting this miRNA had an adverse impact and resulted in increased intestinal tissue injury and Mode-K cell damage. From a mechanistic perspective, miR-26b-5p was predicted to target DAPK1, which was related to cellular apoptosis. Luciferase reporter assay results confirmed that miR-26b-5p directly targets DAPK1 in Mode-K cells, thereby suppressing OGD/R-induced cell apoptosis. Our findings show that miR-26b-5p may prevent intestinal I/R injury via targeting DAPK1 and inhibiting intestinal mucosal cell apoptosis, suggesting that this miRNA may be a viable target for the treatment of intestinal I/R injury.

Vanadium-doped cobalt oxide materials have emerged as a promising class of catalysts for the oxygen evolution reaction. Previous studies suggest vanadium doping in crystalline Co spinel materials tunes the electronic structure and stabilizes surface intermediates. We report a CoV2O4 material that shows good activity for the oxygen evolution reaction. However, postmortem characterization of the catalyst material shows dissolution of vanadium resulting in an amorphous CoOx material, suggesting that this vanadium-free material, and not CoV2O4, is the active catalyst. This study highlights the importance of postmortem characterization prior to mechanistic and computational analysis for this class of materials.

Molecular electrocatalysts show promise for energy-relevant multi-electron transformations due to their rationally-tunable activity and selectivity from systematic ligand modifications. However, su...

In contrast to conventional vacuum-based deposition techniques, a more cost-effective solution-based process for metal-dielectric-metal (MDM) structural color was developed. Conformal coating of the MDM structures with different colors were achieved on various types of substrates regardless of their conductivity.

Noble metal-based heterogeneous catalysts usually suffered from limited strategies for modifying their selectivity as compared with the homogeneous counterparts. Herein, we reported the electrostatically mediated selectivity of Pd nanocatalyst of usual supported Pd nanoparticles for total hydrogenation of furfural by enhancing the interfacial electric field using visible light and a rectifying contact with semiconductive supports to promote preferred adsorption of C Ogroups of furfural to the Pd side. This concept-new approach showed the potential to replace traditional organic ligands with light. The Pd nanoparticles deposited on a semiconductor support, optimized to be g-C 3 N 4 (Pd/CN) in this work, exhibits outstanding selectivity (≥ 97%) to tetrahydrofurfuryl alcohol, far surpassing the selectivity of reported single-phase Pd nanocatalysts.

Background: Propofol is a widely used anesthetic and sedative, which has been reported to exert an anti-inflammatory effect. TLR4 plays a critical role in coordinating the immuno-inflammatory response during sepsis. Whether propofol can act as an immunomodulator through regulating TLR4 are still unclear. In view of its potential as a sepsis therapy, we investigated the mechanisms underlying the immunomodulatory activity of propofol. Methods: The effects of propofol on TLR4 and Rab5a (a master regulator involved in intracellular trafficking of immune factors) were investigated in macrophage (from Rab5a -/- and WT mice) following treatment with lipopolysaccharide or cecal ligation and puncture in vitro and in vivo, and in peripheral blood monocyte from sepsis patients. Findings: We showed that propofol reduced membrane TLR4 expression on macrophage in vitro and in vivo. Rab5a participated in TLR4 intracellular trafficking and both Rab5a expression and the interaction between Rab5a and TLR4 were inhibited by propofol. We also showed Rab5a upregulation in peripheral blood monocyte of septic patients, accompanied by increased TLR4 expression on the cell surface. Both were correlated with SOFA score of sepsis patients and higher expression of Rab5a were found in septic non-survivors. Interpretation: We demonstrated that Rab5a regulates intracellular trafficking of TLR4 and that propofol reduces membrane TLR4 expression on macrophages by targeting Rab5a. Our study not only reveals a novel mechanism for the immunomodulatory effect of propofol but also indicates that Rab5a may be a potential therapeutic target against sepsis. Funding: National Natural Science Foundation of China [81671955, 81730058] Declaration of Interest: The authors declare that they have no conflict of interest. Ethical Approval: C57/BL mice were obtained from Guangdong Medical Laboratory Animal Center (Guangzhou, China). Rab5a knockout mice were purchased from Cyagen Biosciences (Guangzhou, China). All animal experiments were reviewed and approved by the Ethics Committee of Southern Medical University.

Vanadium-doped cobalt oxide materials have emerged as a promising class of catalysts for the oxygen evolution reaction. Previous studies suggest vanadium doping in crystalline Co spinel materials tunes the electronic structure and stabilizes surface intermediates. We report a CoV2O4 material that shows good activity for the oxygen evolution reaction. However, postmortem characterization of the catalyst material shows dissolution of vanadium resulting in an amorphous CoOx material, suggesting that this vanadium-free material, and not CoV2O4, is the active catalyst. This study highlights the importance of postmortem characterization prior to mechanistic and computational analysis for this class of materials.

The safety of mining area is an important part of China's coal mine production, and it is also the main factor related to the safety of people's life and property. Building a smart and Internet-based security monitoring system has become the key to solving the safety of mine production and construction. Based on the technology of zigbee wireless module and RS-485 bus, this paper designs a wireless + wired underground safety monitoring and management solution to complete real-time monitoring and safety management of underground mobile personnel and production equipment.

The low-energy threshold and the large detector size of Precision IceCube Next Generation Upgrade (PINGU) can make the study on neutrino oscillations with a planet-scale baseline possible. In this task, we consider the configuration that neutrinos are produced at CERN and detected in the PINGU detector, as a benchmark. We discuss its sensitivity of measuring the size of non-standard interactions (NSIs) in matter, which can be described by the parameter $\epsilon_{\alpha\beta}$ ($\alpha$ and $\beta$ are flavors of neutrinos). We find that the CERN-PINGU configuration improves $\tilde{\epsilon}_{\mu\mu}\equiv\epsilon_{\mu\mu}-\epsilon_{\tau\tau}$ and $\epsilon_{\mu\tau}$ significantly compared to the next-generation accelerator neutrino experiments. Most of degeneracy problems in the precision measurements can be resolved, except the one for $\tilde{\epsilon}_{\mu\mu}\sim-0.035$. Moreover, we point out that this configuration can also be used to detect the CP violation brought by NSIs. Finally, we compare the physics potential in this configuration to that for DUNE, T2HK and P2O, and find that the CERN-PINGU configuration can significantly improve the sensitivity to NSIs., Comment: 8 pages, 7 figures, make a comparison with other LBL experiments and add more references

The exploitation of metal-free organic polymers as electrodes for water splitting reactions is limited by their presumably low activity and poor stability, especially for the oxygen evolution reaction (OER) under more critical conditions. Now, the thickness of a cheap and robust polymer, poly(p-phenylene pyromellitimide) (PPPI) was rationally engineered by an in situ polymerization method to make the metal-free polymer available for the first time as flexible, tailorable, efficient, and ultra-stable electrodes for water oxidation over a wide pH range. The PPPI electrode with an optimized thickness of about 200 nm provided a current density of 32.8 mA cm-2 at an overpotential of 510 mV in 0.1 mol L-1 KOH, which is even higher than that (31.5 mA cm-2 ) of commercial IrO2 OER catalyst. The PPPI electrodes are scalable and stable, maintaining 92 % of its activity after a 48-h chronoamperometric stability test.

The greenhouse effect and global warming are serious problems because the increasing global demand for fossil fuels has led to a rapid rise in greenhouse gas exhaust emissions in the atmosphere and disruptive changes in climate. As a major contributor, CO2 has attracted much attention from scientists, who have attempted to convert it into useful products by electrochemical or photoelectrochemical reduction methods. Facile design of efficient but inexpensive and abundant catalysts to convert CO2 into fuels or valuable chemical products is essential for materials chemistry and catalysis in addressing global climate change as well as the energy crisis. Herein, we show that two-dimensional fewlayer graphitic carbon nitride (g-C3N4) can function as an efficient metal-free electrocatalyst for selective reduction of CO2 to CO at low overpotentials with a high Faradaic efficiency of ~ 80%. The polarized surface of ultrathin g-C3N4 layers (thickness: ~ 1 nm), with a more reductive conduction band, yields excellent electrochemical activity for CO2 reduction.

Engineering the adsorption of molecules on active sites is an integral and challenging part for the design of highly efficient transition-metal-based catalysts for methanol dehydrogenation. A Mott-Schottky catalyst composed of Ni nanoparticles and tailorable nitrogen-doped carbon-foam (Ni/NCF) and thus tunable adsorption energy is presented for highly efficient and selective dehydrogenation of gas-phase methanol to hydrogen and CO even under relatively high weight hourly space velocities (WHSV). Both theoretical and experimental results reveal the key role of the rectifying contact at the Ni/NCF boundaries in tailoring the electron density of Ni species and enhancing the absorption energies of methanol molecules, which leads to a remarkably high turnover frequency (TOF) value (356 mol methanol mol-1 Ni h-1 at 350 °C), outpacing previously reported bench-marked transition-metal catalysts 10-fold.

The direct activation of oxygen molecules in the gas phase at the interface of solid (catalyst), liquid (electrolyte) and gas (oxygen gas) is highly alluring for the oxygen reduction reaction (ORR) catalyst in a liquid-phase reactor. Such a multiphase pathway without the limitation of the diffusion rate of the dissolved oxygen molecules promises a much higher catalytic efficiency. However, a stable gas–liquid–solid interface can hardly be maintained due to the high surface tension of the aqueous solution to repel the gas phase on the surface of conventional ORR electrodes. Taking advantage of graphene layers with super-absorbing nature, we designed a dendritic carbon structure catalyst to stabilize oxygen bubbles in the nano-intervoids of the dendrites without loss of conductivity and structural integrity, achieving the direct reduction of oxygen gas in an aqueous electrolyte and an ultra-high ORR current density without a diffusion controlled plateau.

Complex structures from nanoparticles are found in rocks, soils, and sea sediments but the mechanisms of their formation are poorly understood, which causes controversial conclusions about their genesis. Here we show that graphene quantum dots (GQDs) can assemble into complex structures driven by coordination interactions with metal ions commonly present in environment and serve a special role in Earth's history, such as Fe3+ and Al3+ . GQDs self-assemble into mesoscale chains, sheets, supraparticles, nanoshells, and nanostars. Specific assembly patterns are determined by the effective symmetry of the GQDs when forming the coordination assemblies with the metal ions. As such, maximization of the electronic delocalization of π-orbitals of GQDs with Fe3+ leads to GQD-Fe-GQD units with D2 symmetry, dipolar bonding potential, and linear assemblies. Taking advantage of high electron microscopy contrast of carbonaceous nanostructures in respect to ceramic background, the mineralogical counterparts of GQD assemblies are found in mineraloid shungite. These findings provide insight into nanoparticle dynamics during the rock formation that can lead to mineralized structures of unexpectedly high complexity.

A previously reported cobalt complex featuring a tetraimidazolyl-substituted pyridine chelate is an active water oxidation electrocatalyst with moderate overpotential at pH 7. While this complex decomposes rapidly to a less-active species under electrocatalytic conditions, detailed electrochemical studies support the agency of an initial molecular catalyst. Cyclic voltammetry measurements confirm that the imidazolyl donors result in a more electron-rich Co center when compared with previous pyridine-based systems. The primary changes in electrocatalytic behavior of the present case are enhanced activity at lower pH and a marked dependence of catalytic activity on pH.

In this paper, we propose a generalized Kretschmann configuration that employs a metagrating to replace the prism, realizing polarization-controlled efficient and unidirectional surface plasmon polariton (SPP) excitation. This dielectric phase gradient metagrating on the top surface of a silica substrate is designed to deflect incident light, which subsequently launches SPP wave by means of momentum matching on the metal film coated on the bottom surface. A series of metagratings is designed to enable the SPP excitation by circularly or linearly polarized incident light. The flexibility and tunability of this design to efficiently control SPPs show potential to find wide applications in diverse integrated optics and SPP devices.

This study investigates the consensus problem for cooperative heterogeneous agents with non-linear dynamics in a directed communication network. Global bounded consensus is studied by employing a quadratic Lyapunov function, and a distributed consensus protocol is designed by solving a few lower-dimension linear matrix inequalities associated with the dynamics of the heterogeneous agents. A sufficient condition corresponding to the semi-positive definiteness of the Laplacian matrix and the non-linear dynamics of each agent is obtained to guarantee the boundedness of consensus. In particular, to avoid the calculation of matrix eigenvalues, a sufficient condition is also obtained in the form of several scalar inequalities involving the coupling strengths and the property of all paths between agent pairs under a proper path strategy. The presented framework for designing protocols is quite simple with limited conservatism, which can be effectively used to design consensus protocols of various weighted and directed networks.

Proper disposal of waste paper is an important waste-management concern. We developed a facile and inexpensive method to transform waste paper into graphene-tethered carbon fiber composite paper (GCCP). Urea was the only additive for the carbonization of the GCCP. The as-obtained GCCP exhibited high electrical conductivity, and GCCP/polydimethyl siloxane (GCCP/PDMS) composites showed good stretchability with great electromechanical stability. The surface of the GCCP membrane was observed to be superhydrophobic; this property apparently endowed the membrane with the ability to separate oil from water in our experiments, which makes GCCP a promising candidate material for cleanup of oil spills. The hierarchical structure, N doping feature and low decoration with Pt make GCCP a potential electrocatalyst for oxygen reduction, oxygen evolution and hydrogen evolution reactions with superior activity and high stability, and hence also a promising candidate for application as a direct working electrode in future energy systems.

This study is concerned with the problem of dynamical distributed consensus for multi-agent systems with nonlinear dynamics. Following the nearest neighbour rule, an adaptive consensus protocol is designed for such systems without using any global information, where the coupling weight of an agent from its neighbours adaptively updates according to the differences from the mean activity of the agent and its neighbours. The analysis shows that, under some mild assumptions, the adaptive law can achieve local and global consensus for any network with connected communication graph. Numerical simulations, illustrated by a common second-order consensus example, are performed to demonstrate the effectiveness of the presented results.

The goal of traffic management is to efficiently allocate network resources via adjustment of source transmission rates and routes selection. Mathematically, it aims to solve a traditional utility maximization problem in a fair and distributed manner. In this paper, we first develop a generalized multi-path utility maximization problem which features a weighted average of the classical Kelly's formulation and the Voice's model. Next, we design from this broader framework a family of multi-path dual congestion control algorithms whose equilibrium point can both achieve a desired bandwidth utilization and preserve a notion of fairness among competing users. Global stability can be guaranteed for the proposed schemes in the absence of delays by use of a totally novel Lyapunov function. Moreover, when heterogeneous propagation delays are taken into account, we establish decentralized and scalable sufficient conditions for robust global stability by constructing a reasonable Lyapunov-Krasovskii functional candidate. These conditions give estimates for the maximum admissible delays that the controller can tolerate without losing stability. Finally, we verify the results through simulation.

The design and implementation of the Remote Monitor System for Simulation Elevator Based on EPA were appeared. The Remote Monitor System consists of the device layer, control layer, the server layer and client layer, the monitoring software, configuration software and so on, which implements to the simulated elevator data acquisition and intelligent control of output and remote monitoring.

The design and implementation of the Ethernet Control System Based on EPA were appeared. The Ethernet Control System consists of the device layer, control layer, management structure. The use of EPA configuration software control network configuration, performance monitoring, the device performs to achieve the control object control strategy.

The DC speed regulating system has many difficult issues such as system parameters and PID control parameters are difficult to determine. On the basis of model for a single closed-loop DC speed regulating system, this paper puts forward a method of PID parameters self-tuning based on the step response detection and reduced order equivalent. First, detect system step response and get response parameters. Then equal it to a second order system model, and achieve optimal PID control parameters based on optimal second order system to realize of PID parameters self-tuning. The PID parameters self-tuning process of DC speed regulating system is simulated with the help of MATLAB/Simulink. The simulation results show that the method is simple and effective. The system can obtain good dynamic and static performance when the PID parameters are applied to DC speed regulating system.

In this paper, we obtain some existence results for a class of singular semilinear elliptic problems where we improve some earlier results of Zhijun Zhang. We show the existence of entire positive solutions without the monotonic condition imposed in Zhang’s paper. The main point of our technique is to choose an approximating sequence and prove its convergence. The desired compactness can be obtained by the Sobolev embedding theorems.