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Controlling interactions between proteins and nanoparticles in electrolyte solutions is crucial for advancing biological sciences and biotechnology. The assembly of charged nanoparticles (NPs) and proteins in aqueous solutions can be directed by modifying the salt concentration. High concentrations of monovalent salt can induce the solubilization or crystallization of NPs and proteins. By using a multiscale coarse-grained molecular dynamics approach, we show that, due to ionic correlations in the electrolyte, NPs pairs at high monovalent salt concentrations interact via remarkably strong long-range attractions or repulsions, which can be split into three regimes depending on the surface charge densities of the NPs. NPs with zero-to-low surface charge densities interact via a long-range attraction that is stronger and has a similar range to the depletion attraction induced by polymers with radius of gyrations comparable to the NP diameter. On the other hand, moderately charged NPs with smooth surfaces as well as DNA-functionalized NPs with no possibility of hybridization between them interact via a strong repulsion of range and strength larger than the repulsion predicted by models that neglect ionic correlations, including the Derjaguin-Landau-Vervey-Overbeek (DLVO) model. Interactions between strongly charged NPs (>2 e/nm²), both types smooth and DNA-functionalized NPs, show an attractive potential well at intermediate-to-high salt concentrations, which demonstrates that electrolytes can induce aggregation of strongly charged NPs. Our work provides an improved understanding of the role of ionic correlations in NP assembly and design rules to utilize the salting-out process to crystallize NPs. [ABSTRACT FROM AUTHOR]

The Fleet Assignment Problem (FAP) of aircraft scheduling in airlines is studied, and the optimization model of FAP is proposed. The objective function of this model is revenue maximization, and it considers comprehensively the difference of scheduled flights and aircraft models in flight areas and mean passenger flows. In order to solve the model, a self-adapting genetic algorithm is supposed to solve the model, which uses natural number coding, adjusts dynamically crossover andmutation operator probability, and adopts intelligent heuristic adjusting to quicken optimization pace. The simulation with production data of an airline shows that the model and algorithms suggested in this paper are feasible and have a good application value. [ABSTRACT FROM AUTHOR]

Abstract-In this paper, the influence of one-sample delay for sampling and computation in digital control on the bandwidth of the inner current loop of a 400-Hz ground power unit (GPU) is analyzed first. The results show that it is difficult and even impossible for high-power 400-Hz GPUs to maintain low total harmonic distortion content in the output voltage with the conventional proportional-integral-based double-loop control. To improve the performance, resonant controllers with parallel structure which are widely used in active power filters are applied to the single-loop control of the 400-Hz GPU. The parameter design criterion for the parallel resonant controllers is discussed in the discrete time domain. Meanwhile, adoption of-proportional gain in the single-loop control is investigated. The results show that it can improve the performance little and may cause instability problems. Comparisons between different control methods for the 400-Hz GPU are also made, and the single-loop control method in this paper seems to be the most suitable one in terms of simplicity and performance. Experiments on a 16-b fixed-point DSP-controlled 90-kVA 400-Hz GPU prototype show satisfactory results of the single-loop method feeding linear/nonlinear and balanced/unbalanced loads. [ABSTRACT FROM AUTHOR]

A well-defined photosensitive polymer whose chromophores were bound with pH-labile cyclic acetal linkages, i.e., poly[5-ethyl-5-methacryloyloxymethyl-2-styryl-[1,3]dioxane] (PEMSD), was synthesized via RAFT polymerization of EMSD monomer under a mild visible light radiation at 30 °C. Kinetic studies indicated the well-controlled behavior of this RAFT polymerization. The living character of this RAFT polymerization was confirmed by the well-controlled chain-extending RAFT polymerization using an above-synthesized PEMSD as a macromolecular chain transfer agent under this mild visible light radiation at 30 °C. 1H NMR analysis evidenced the intact cyclic acetal linkages and 100% E-cinnamyl chromophores of this PEMSD polymer synthesized under these mild conditions. Isomerization of E-cinnamyl chromophores of this polymer was triggered on exposure to UV radiation, particularly in a wave range of 254−365 nm, with strong light intensity dependence. This photoisomerization reached equilibrium at ca. 65% Z-cinnamyl formation. On photoisomerization of E-cinnamyl chromophores, the maximum absorption wavelength (λ max) of this PEMSD polymer blue-shifted from 252 nm (100% E-cinnamyl) to 244 nm ( E/ Z= 44:56); accordingly, its molar extinction coefficient at λ maxlinearly decreased from 1.97 × 10 4M −1cm −1to 1.41 × 10 4M −1cm −1. Moreover, this photoisomerization improved the irregularity of polymer chains, thus its glass transition temperature linearly decreased from 119 °C (100% E-cinnamyl) to 99 °C ( E/Z= 37:63). More importantly, this photoisomerization enhanced the steric hindrance and hydrophobicity of cyclic acetal linkages and shielded the cyclic acetal linkages from the proton attack and hydration. This significantly improved the stability of cyclic acetal linkages neighboring Z-cinnamyl chromophores. On the other hand, this photoisomerization improved the irregularity and loose packing of polymer chains, leading to even more labile cyclic acetal linkages neighboring E-cinnamyl chromophores than those in 100% E-cinnamyl PEMSD polymer. In both 100% E-cinnamyl and partially Z-cinnamyl-isomerized cases, higher molecular weight of PEMSD polymer led to a slower hydrolysis process of its cyclic acetal linkages. This remarkable phototunable stability of pH-labile cyclic acetal linkages rendered potential applications in photosensors and light-triggered drug delivery. [ABSTRACT FROM AUTHOR]

Cotton fiber is a raw material for the global textile industry and fiber quality is essential to its industrial application. Carotenoids are plant secondary metabolites that may serve as dietary components, regulate light harvesting, and scavenge reactive oxygen species. Although carotenoids accumulate predominantly in rapidly elongating cotton fibers, their roles in cotton fiber development remain poorly understood. In this study, a fiber-specific promoter proSCFP was applied to drive the expression of GhOR1Del, a positive regulator of carotenoid accumulation, to upregulate the carotenoid level in cotton fiber in planta. Fiber length, strength, and fineness were increased in proSCFP:GhOR1Del transgenic cotton and abscisic acid (ABA) and ethylene contents were increased in elongating fibers. The ABA downstream regulator GhbZIP27a stimulated the expression of the ethylene synthase gene GhACO3 by binding to its promoter, suggesting that ABA promoted fiber elongation by increasing ethylene production. These findings suggest the involvement of carotenoids and ABA signaling in promoting cotton fiber elongation and provide a strategy for improving cotton fiber quality. [ABSTRACT FROM AUTHOR]

Although the onset time of chemical reactions can be manipulated by mechanical, electrical, and optical methods, its chemical control remains highly challenging. Herein, we report a chemical timer approach for manipulating the emission onset time of chemiluminescence (CL) reactions. A mixture of Mn2+, NaHCO3, and a luminol analog with H2O2 produced reactive oxygen species (ROS) radicals and other superoxo species (superoxide containing complex) with high efficiency, accompanied by strong and immediate CL emission. Surprisingly, the addition of thiourea postponed CL emission in a concentration-dependent manner. The delay was attributed to a slow-generation-scavenging mechanism, which was found to be generally applicable not only to various types of CL reagents and ROS radical scavengers but also to popular chromogenic reactions. The precise regulation of CL kinetics was further utilized in dynamic chemical coding with improved coding density and security. This approach provides a powerful platform for engineering chemical reaction kinetics using chemical timers, which is of application potential in bioassays, biosensors, CL microscopic imaging, microchips, array chips, and informatics. [ABSTRACT FROM AUTHOR]

In this paper, a novel single-phase five-level inverter is proposed using coupled inductors. This inverter can output five-level voltage with only one dc source. No split of the dc voltage capacitor is needed, totally avoiding the voltage balancing problem in conventional multilevel inverters. The level of the output voltage is only half of the dc-link voltage in all conditions, leading to much reduced dv/dt . This inverter is based on the widely used three-arm power module and the voltage stresses on all the power switches are the same, making it very easy to construct. Operation mechanism of this inverter is analyzed and the possible switching patterns are investigated. Based on these analyses, a novel optimized modulation scheme is presented. With this modulation method, no dc components exist in the inductor currents, which is very helpful for minimization of the inductors. Simulation and experimental results show the validity of the proposed inverter together with the optimized modulation scheme. [ABSTRACT FROM AUTHOR]

[Objectives] To identify and analyze chemicai component. in Zhideke Granules by ultra performance liquii chromatography-quadrupole/electrostatic field orbitrap high resolution mast spectrometry (UPLC-Q-Orbitrap HRMS). #Mettods] Zhideke Granule wero isolated on a Thermo Hypersil Gold C18 column (2.1 mm x 100 mm, 1.9 |im). The mobile phase was 0.1 % formic acid acetonitrile and 0.1 % formic acid aqueous solution (containing 10 mmol ammonium acetate) with gradient elution. Chemical components in Zhineke Granules were rapidly isolated and identiXed by HRMS in the positive and neeative ion mode with full scan data-dependent two stage threshold-triggered mcs modes (Full MS/dd-MS2). # Results] The secondait fragment ion information of the taraet compound wot selected and compared wit the compound reported in the databasee and related literatures for furWer confirmation. In wwi, 30 chemical compounde were identified, including 12 flavonoids and glycosidee, 9 oraanic acide, 3 nitrogen-containing compounde, and 6 other componente. # Conclusions] In Ohn study, the UPLC-Q-Orbitrap HRMS was used for the first time to analyze the chemical components in Zhideke Granules. It Is intended to provide a referencc foe thequaeityeeaeuation and fuatheaetudyofphaamacodynamicmateaiaeeofZhidekeGaanueee. [ABSTRACT FROM AUTHOR]

[Objectives] To study the volatile components and antibacterial effects of 11 kinds of Aurantii Fructus Immaturus processed products. [Methods] 11 kinds of Aurantii Fructus Immaturus processed products were obtained according to the traditional processing method, the volatile oil was extracted by steam distillation, and the composition of volatile oil in the 11 kinds of processed products was analyzed by gas chromatography-mass spectrometry（GC-MS）. the relative percentage content of each component in these 11 kinds of processed products was determined using the peak area normalization. The drug sensitivity activity of the volatile oil of these 11 kinds of processed products was tested using the K-B paper diffusion method and the minimum inhibition volume fraction of volatile oil of these 11 kinds of processed products was tested using the microdilution method. [Results] The highest yield of volatile oil of 11 kinds of these processed products was baking（5.193%）, and the lowest was stir-bake to scorch（1.998%）. A total of 36 chemical components were identified from the volatile oils of these 11 kinds of processed products. The components with the most volatile oil were stir-bake to scorch（24 kinds）, and the components with the least volatile oil were the method of processing with rice-washed water（15 kinds）. They contain 8 kinds of common chemical components, such as limonene, linalool, myrcene, α-pinene. The highest content of limonene came from processing with honey（60.93%）, the lowest came from processing with rice-washed water（55.25%）; the highest content of linalool came from processing with rice-washed water（7.139%）, the lowest came from processing with honey（5.436%）; the highest content of myrcene came from processing with honey（1.899%）, the lowest came from stir-bake to scorch（1.632%）; the highest content of α-pinene came from raw Aurantii Fructus Immaturus（2.355%）, and the lowest came from stir-bake to scorch（1.618%）. The volatile oil of these 11 kinds of Aurantii Fructus Immaturus processed products has good antibacterial effect on Escherichia coli and Staphylococcus aureus. [Conclusions] The oil yields of volatile oils of 11 kinds of Aurantii Fructus Immaturus processed products are different, the content of limonene is significantly different, and the changes of other chemical components and their contents are not significantly different. The volatile oil of 11 kinds of Aurantii Fructus Immaturus processed products has certain antibacterial effect. [ABSTRACT FROM AUTHOR]

In this paper, an improved pulse width modulation (PWM) method for chopper-cell (or half-bridge)based modular multilevel converters (MMCs) is proposed. This method can generate an output voltage with maximally 2N+1 (where N is the number of submodules in the upper or lower arm of MMC) levels, which is as great as that of the carrier-phase-shifted PWM (CPSPWM) method. However, no phase-shifted carrier is needed. Compared with the existing submodule unified pulse width modulated (SUPWM) method, the level number of the output voltage is almost doubled and the height of the step in the staircase voltage is reduced by 50%. Meanwhile, the equivalent switching frequency in the output voltage is twice that of the conventional SUPWM method. All these features lead to much reduced harmonic content in the output voltage. What is more, the voltages of the submodule capacitors can be well balanced without any close-loop voltage balancing controllers which are mandatory in the CPSPWM schemes. Simulation and experimental results on a MMC-based inverter show validity of the proposed method. [ABSTRACT FROM AUTHOR]

This study evaluated the antioxidant activities of the extracts of Jasminum nervosum Lour. stems along with the effects of different extract solvents on total phenolics (TP), total flavonoids (TF), and antioxidant potential. The antioxidant activity of the extracts was assessed using the following methods: DPPH, ABTS+ both free radicals scavenging assays, and reducing assays. TP and TF were detected by spectrophotometric and HPLC methods. In former methods, the highest amount of TP content was ethyl acetate extract (EAE), expressed as gallic acid equivalents. The greatest TF content was in the n-butanol extract (BE), expressed as lutin equivalents. No significant difference was observed in the TP/TF content between these two extracts. The antioxidant activity and TP/TF content of three extracts seemed to follow the same trend. This implied that there is a good correlation between antioxidant activities and TP/TF content. But in HPLC methods, EAE contained the highest content of lutin and gallic acid, which decreased in the same order of EAE>BE>PE, the rank order of TP/TF content of EAE and BE were different according to antioxidant ability. The overall results showed that the EAE and BE were richer in phenolics and flavonoids than petroleum ether extract (PE), and may represent a good source of antioxidants. [ABSTRACT FROM AUTHOR]

The derivation of the equivalent circuit for a single-sided linear induction motor (SLIM) is not straightforward, particularly if it includes longitudinal end effects from the cut-open primary magnetic path, transversal edge effects from the differing widths between the primary lamination and secondary sheet, and half-filled primary slots. This paper proposes an improved series equivalent circuit for this machine. The longitudinal end effects are estimated using three different impedances representing the normal, forward, and backward flux density waves in the air gap, whose two boundary conditions are deduced by introducing the conception of magnetic barrier surface. The transversal edge effects are accounted for by correction coefficient C̅t and air-gap flux density correction coefficient C̅b. Using the series circuit, the performance of the SLIM was assessed in a similar manner to a rotating induction machine. A 4-kW SLIM prototype was tested, which validated the simulation technique. [ABSTRACT FROM AUTHOR]

An abstract of the article "C-Terminal Part of Alpha-Synuclein Mediates its Activity in Promoting Proliferation of Dopaminergic Cells," by Juanjuan Yin, Tao Wang, Junyan Han, Chen Zhang, Qiulan Ma, Xin Li, Furong Cheng, Yaohua Li, Guangwei Liu, Piu Chan, and colleagues, is presented.