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In order to solve the problems of low transmission rate and large device size of electro-optical modulator, an electro-optic half subtractor based on silicon-based hybrid surface plasmon polariton waveguide is proposed in this study. The proposed device utilizes three units metal-oxide-semiconductor capacitor structure to achieve the half subtractor logic function of electro-optic control, improving the transmission rate of the electro-optic half subtractor while also reducing the device size using surface plasmon polariton technology, with a size of only 32 μm × 4.3 μm. At the same time, the use of hybrid silicon waveguides reduces the sharp Ohmic attenuation caused by surface plasmon polaritons and reduces optical insertion losses (ILs). The simulation results show that when the electro-optic half subtractor operates at the wavelength of 1,550 nm, the IL difference is 1.0 dB in each state, the transmission rate of the device is 0.75 Tbit/s, and the energy consumption is 12.69 fj/bit.

This article proposes an on-chip optical temperature sensor based on a cascaded microring resonator, which is composed of a reference ring and a sensing ring cascaded with different temperature sensitivities and free spectral ranges. By changing the temperature of the sensing window environment, the thermal optical effect of the waveguide causes a change in the refractive index of the waveguide, which affects the temperature sensitivity and free spectrum changes of the sensor. The output spectral response of the sensor shifts, achieving temperature sensing detection. The experimental results show that the temperature sensitivity of this microring cascaded temperature sensor is 303.6 pm/°C, which is 3.65 times the limit of a single microring temperature sensitivity of 83 pm/°C. The temperature-sensing range of the sensor is 100°C, which can well meet the temperature-monitoring requirements of ultra-large-scale integrated circuits.

Oxygen evolution reaction catalysts capable of working efficiently in acidic media are highly demanded for the commercialization of proton exchange membrane water electrolysis. Herein, we report a Zn-doped RuO2 nanowire array electrocatalyst with outstanding catalytic performance for the oxygen evolution reaction under acidic conditions. Overpotentials as low as 173, 304, and 373 mV are achieved at 10, 500, and 1000 mA cm−2, respectively, with robust stability reaching to 1000 h at 10 mA cm−2. Experimental and theoretical investigations establish a clear synergistic effect of Zn dopants and oxygen vacancies on regulating the binding configurations of oxygenated adsorbates on the active centers, which then enables an alternative Ru−Zn dual-site oxide path of the reaction. Due to the change of reaction pathways, the energy barrier of rate-determining step is reduced, and the over-oxidation of Ru active sites is alleviated. As a result, the catalytic activity and stability are significantly enhanced. Ru-based materials are promising catalysts for oxygen evolution reaction in acidic condition, but their catalytic performance needs to be further improved. Here, the authors report Zn-RuO2 nanowires with a Ru−Zn dual-site oxide reaction pathway with enhanced activity and stability for acidic oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

Hydrogen sulfide (H 2 S) is the most recently discovered gasotransmitter molecule that activates multiple intracellular signaling pathways and exerts concentration-dependent antitumor effect by interfering with mitochondrial respiration and inhibiting cellular ATP generation. Inspired by the fact that H 2 S can also serve as a promoter for intracellular Ca2+ influx, tumor-specific nanomodulators (I-CaS@PP) have been constructed by encapsulating calcium sulfide (CaS) and indocyanine green (ICG) into methoxy poly (ethylene glycol) -b- poly (lactide -co- glycolide) (PLGA-PEG). I-CaS@PP can achieve tumor-specific biodegradability with high biocompatibility and pH-responsive H 2 S release. The released H 2 S can effectively suppress the catalase (CAT) activity and synergize with released Ca2+ to facilitate abnormal Ca2+ retention in cells, thus leading to mitochondria destruction and amplification of oxidative stress. Mitochondrial dysfunction further contributes to blocking ATP synthesis and downregulating heat shock proteins (HSPs) expression, which is beneficial to overcome the heat endurance of tumor cells and strengthen ICG-induced photothermal performance. Such a H 2 S-boosted Ca2+-involved tumor-specific therapy exhibits highly effective tumor inhibition effect with almost complete elimination within 14-day treatment, indicating the great prospect of CaS-based nanomodulators as antitumor therapeutics. A biodegradable nanomodulator (I-CaS@PP) was constructed by encapsulating CaS and ICG into PLGA-PEG, which helped controllably release H 2 S and Ca2+ in the acidic tumor microenvironment for synergistic cascade cancer therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Nanozyme‐based tumor catalytic therapy has attracted widespread attention in recent years, but its therapeutic outcome is drastically diminished by species of nanozyme, concentration of substrate, pH value, and reaction temperature, etc. Herein, a novel Cu‐doped polypyrrole nanozyme (CuP) with trienzyme‐like activities, including catalase (CAT), glutathione peroxidase (GPx), and peroxidase (POD), is first proposed by a straightforward one‐step procedure, which can specifically promote O2 and ·OH elevation but glutathione (GSH) reduction in tumor microenvironment (TME), causing irreversible oxidative stress damage to tumor cells and reversing the redox balance. The PEGylated CuP nanozyme (CuPP) has been demonstrated to efficiently reverse immunosuppressive TME by overcoming tumor hypoxia and re‐educating macrophage from pro‐tumoral M2 to anti‐tumoral M1 phenotype. More importantly, CuPP exhibits hyperthermia‐enhanced enzyme‐mimic catalytic and immunoregulatory activities, which results in intense immune responses and almost complete tumor inhibition by further combining with αPD‐L1. This work opens intriguing perspectives not only in enzyme‐catalytic nanomedicine but also in macrophage‐based tumor immunotherapy. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of exponential stability for the Hopfield neural network with time-varying delays. Different from the existing results, we establish new stability criteria by employing the method of variation of constants and Gronwall's integral inequality. Finally, we give several examples to show the effectiveness and applicability of the obtained criterion. [ABSTRACT FROM AUTHOR]

• Ni-M seed (M = Pt, Pd, Au, Ru, Ag, Cu) nanowires were produced under magnetic field. • Seed metal cations (nucleating agents) clearly influenced the growth of nanowires. • Nanowires showed an exceptional activity to catalyze the ammonia borane hydrolysis. A straightforward method was developed to synthesize Ni-M seed (M = Pt, Pd, Au, Ru, Ag, Cu) nanowires (NWs) under magnetic field using different metal cations as nucleating agents. The type of nucleating agents affected more on the average diameter of the produced Ni-M seed NWs, which varied from tens to hundreds of nanometers. Physical measurements revealed the presence of nucleating metals with contents less than 1.0 at.% to Ni, indicating them to be small amounts of nucleating metals loaded Ni nanowires rather than a pure Ni material. For the hydrolysis of ammonia borane, the as-prepared Ni-M seed NWs exhibited exceptional catalytic activities with significantly improved H 2 production kinetics compared with the pristine Ni material, demonstrating more promising applications of the Ni-M seed NWs in catalysis field. [ABSTRACT FROM AUTHOR]

Since dozens years ago, various metaheuristic methods, such as genetic algorithm, ant colony algorithms, have been successfully applied to combinational optimization problem. However, as one of the members, ITO algorithm has only been employed in continuous optimization, it needs further design for combinational optimization problem. In this paper, a discrete ITO algorithm inspired by ITO stochastic process is proposed for travelling salesman problems (TSPs). Some key operators, such as move operator, wave operator, are redesigned to adapt to combinational optimization. Moreover, the performance of ITO algorithm in different parameter selections and the maintenance of population diversity information are also studied. By combining local search methods (such as 2-opt and LK-opt) with ITO algorithm, our computational results of the TSP problems show that ITO algorithm is currently one of the best-performing algorithms for these problems. [ABSTRACT FROM AUTHOR]

Background: Laccase, a multicopper oxidase that catalyzes the oxidation of phenols, aromatic amines, and benzenethiols, has attracted much attention in applications of organic synthesis, bioremediation, and pulp/textile bleaching. However, free laccases cannot be recycled and are easily inactivated in diverse environmental conditions. Enzyme immobilization is a promising strategy to improve stability, resistance to extreme conditions, and reusability of laccase.Results: In this study, amino-functionalized magnetic Fe3O4 nanoparticles were synthesized for co-immobilization of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and laccase by glutaraldehyde cross-linking method. The magnetic nanoparticles were characterized with FTIR, XRD and VSM. Cyclic voltammetry was carried out to verify electrochemical behaviors of the co-immobilized laccase and TEMPO nanoparticles. When the co-immobilized laccase and TEMPO nanoparticles were used to decolorize acid fuchsin, the maximum decolorization rate of 77.41% was obtained with the ratio of TEMPO to laccase being 0.3 mM/g:120 U/g.Conclusion: The co-immobilized nanoparticles retained above 50% residual activity after eight cycles of operation, which presented an approach to develop a co-immobilized laccase and mediator system for potential industrial application. [ABSTRACT FROM AUTHOR]