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Single‐atom nanozymes (SAzymes) can maximize atomic utilization efficiency and construct highly active catalytic sites for biomedical applications. Herein, atomically dispersed iron (Fe) and cobalt (Co) dual sites anchored N‐doped graphene carbon (FeCoCN) catalyst is rationally constructed to achieve photothermally augmented catalytic oxidation for effective biocatalytic tumor nanotherapy. Compared with Fe SAzyme, FeCoCN SAzyme can significantly accelerate the charge transfer and improve the activity of catalytic reactions. Co‐doping optimizes coordination structure and charge redistribution by facilitating the ratio of Fe2+ and regulating charge transfer between different metal sites and nearby coordination atoms. Bimetallic FeCoCN SAzyme possessed an ultra‐high affinity for substrate H2O2, and the catalytic kinetic Km value (0.589 mm) is superior to natural catalase and most reported nanozymes. The boosted catalytic activity in producing •OH is identified by density functional theory (DFT) studies. In vivo, investigation demonstrates that atomically dispersed Fe and Co dual sites anchored FeCoCN SAzyme significantly suppresses tumor proliferation under NIR laser irradiation by photothermally enhanced catalytic oxidation. Additionally, Fe‐ and Co‐doping in FeCoCN make it suitable as a tracer for T2 magnetic resonance imaging. This work provides a paradigm to rationally design bimetallic SAzymes with enhanced biocatalytic performance for tumor treatment. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii (T. gondii) is a neurotropic protozoan parasite, which can cause mental and behavioural disorders. The present study aimed to elucidate the effects and underlying molecular mechanisms of sertraline (SERT) on T. gondii- induced depression- like behaviours. In the present study, a mouse model and a microglial cell line (BV2 cells) model were established by infecting with the T. gondii RH strain. In in vivo and in vitro experiments, the underlying molecular mechanisms of SERT in inhibiting depression- like behaviours and cellular perturbations caused by T. gondii infection were investigated in the mouse brain and BV2 cells. The administration of SERT significantly ameliorated depression- like behaviours in T. gondii- infected mice. Furthermore, SERT inhibited T. gondii proliferation. Treatment with SERT significantly inhibited the activation of microglia and decreased levels of pro- inflammatory cytokines such as tumour necrosis factor- alpha, and interferon- gamma, by down- regulating tumour necrosis factor receptor 1/nuclear factor- kappa B signalling pathway, thereby ameliorating the depression- like behaviours induced by T. gondii infection. Our study provides insight into the underlying molecular mechanisms of the newly discovered role of SERT against T. gondii- induced depression- like behaviours. [ABSTRACT FROM AUTHOR]

Ear shape of maize (Zea mays L.) is related to ear perimeter, kernel row number, and then kernel yield. To study the inheritance of fasciated ear and the relationship between ear flatness and other ear traits is of great importance in improving ear shape and then increasing yield of maize. In this study, the fasciated ear inbred line Yi16 and normal ear inbred line B73 were used to construct F2 and F2:3 populations to study the correlations between ear flatness and other ear traits, and identify quantitative trait loci (QTL) of fasciated ear‐related traits in two environments. The results showed that ear flatness was positively correlated with cob flatness, ear perimeter, cob perimeter, and kernel row number and negatively correlated with ear length. The broad‐sense heritabilities of ear flatness and cob flatness were 59.01 and 67.38%, respectively. A total of 50 QTL were detected. Three QTL (qCF1, qCF4, and qKRN4a) were detected in all generations and environments, and five QTL (qEF4, qCF7, qCP2, qCP4, and qHKW7) were detected in two generations or two environments. The consistent QTL qEF4, qCF4, and qKRN4a were located in the common region of umc1940–umc1631 (bins 4.09) within a distance of 2.4 cM, explaining >10% of phenotypic variation except qKRN4a in F2. The five pairs of QTL (qEF3‐HC × qEF4‐HC, qCF1‐BB × qCF4‐BB, qCF1‐BB × qCF7‐BB, qKRN1a‐BB × qKRN4a‐BB, and qHKW3‐HC × qHKW7‐HC) were detected to have epistatic effects, contributing 7.31–13.95% of phenotypic variance. [ABSTRACT FROM AUTHOR]

The reliability and stability of a grid-connected converter is vital to the power conversion system. The faults of switching device and current sensor lead to operation failure for a grid-connected converter. An improved model predictive power control (MPPC) based on reconstructed currents is proposed for fault-tolerant operation of a grid-connected converter. Firstly, the three-phase currents are reconstructed using the sampled dc current and normal sensor information according to the relationship between the voltage vector and output currents. Secondly, the predictive power model is built based on fault-tolerant three-phase four-switch topology. Then the reconstructed current is used for the MPPC method. To keep the balance of dc capacitor voltages, the cost function is optimised and the switching vector, which minimises the cost function, is applied to the fault-tolerant converter. Finally, the experiment platform and simulation models are built to verify the proposed method. The results show that the proposed MPPC using reconstructed currents can keep the fault-tolerant operation of the grid-connected converter with sinusoidal currents and stable output power. The proposed method achieves the fault-tolerant operation under switching device and ac current sensor fault, which improve the reliability of the system. [ABSTRACT FROM AUTHOR]

Model predictive control (MPC) strategies have been frequently studied in recent years. To reduce the common-mode voltage (CMV) as well as the current total harmonic distortions (THDs) of the 2-level voltage sources (2L-VSIs), a new MPC strategy is proposed in this study considering both the dead-time and the one-step delay effects. First, the reference voltage vector (VV) prediction based MPC strategy is utilised as it is simple and accurate. Next, the VV preselection strategy is studied in detail to remove the CMV spikes. The effects of the dead time on the CMV are analysed, and an improved VV preselection strategy is presented to reduce the CMV spikes. Then, the one-step delay effects are also analysed, and further improvements are made to completely remove the CMV spikes. Moreover, the maximum variation of the current during one control period is studied in-depth to provide a solid theory foundation for dividing the current sector more accurately. As the six non-zero VVs of the 2L-VSI are fully used in the proposed method, not only the CMV but also the current THDs are reduced. Finally, comparative simulation and experimental studies are carried out to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Under unbalanced grid fault conditions, the current harmonic contents of a three-phase bidirectional AC/DC converter increase significantly and twice grid-frequency ripples exist in both active power and reactive power, which influence the output power quality of the converter. Compared with the conventional finite-state model predictive direct power control (MPDPC), the MPDPC with power compensation (MPDPC-PC) method is proposed for the three-phase bidirectional AC/DC power converter to reduce harmonic currents and output power ripples without extraction of complex positive/negative sequences from the grid voltage/current and phase-locked loop. The power compensation values are expressed by grid voltages and their quadrature signals that lag 90 electrical degrees in the αβ stationary coordinates system. MPDPC-PC exhibits better performance by reducing the harmonic contents of grid currents and eliminating active power or reactive power ripples of the three-phase bidirectional AC/DC converter with flexible reactive power compensation capability. Compared with the MPDPC and linear current control schemes, experimental results confirm the effectiveness of the designed method under unbalanced grid conditions. [ABSTRACT FROM AUTHOR]

RhIII-catalyzed aryl C-H vinylation for the preparation of styrenes by using vinyl acetate, a commercially available and inexpensive compound, as the vinyl source was successfully realized. This method enables various aromatics including N-sulfonyl ketimines, pyridines, azoles, and amides to be vinylated in moderate to good yields. [ABSTRACT FROM AUTHOR]

Dyslipidemia increases the risks for atherosclerosis in part by impairing endothelial integrity. Endothelial progenitor cells (EPCs) are thought to contribute to endothelial recovery after arterial injury. Oxidized low-density lipoprotein (ox-LDL) can induce EPC dysfunction, but the underlying mechanism is not well understood. Human EPCs were cultured in endothelial growth medium supplemented with VEGF (10 ng/mL) and bFGF (10 ng/mL). The cells were treated with ox-LDL (50 µg/mL). EPC proliferation was assayed by using CCK8 kits. Expression and translocation of nuclear factor-kabba B (NF-κB) were evaluated. The level of reactive oxygen species (ROS) in cells was measured using H2DCF-DA as a fluorescence probe. The activity of NADPH oxidase activity was determined by colorimetric assay. Ox-LDL significantly decreased the proliferation, migration, and adhesion capacity of EPCs, while significantly increased ROS production and NADPH oxidase expression. Ox-LDL induced NF-κB P65 mRNA expression and translocation in EPCs. Thus ox-LDL can induce EPC dysfunction at least by increasing expression and translocation of NF-κB P65 and NADPH oxidase activity, which represents a new mechanism of lipidemia-induced vascular injury. [ABSTRACT FROM AUTHOR]

Background and Aims: Sequential therapy is a two-step therapy achieving a promising eradication rate for Helicobacter pylori infection. The rationale of sequential method has been proposed that amoxicillin weakens bacterial cell walls in the initial phase of treatment, preventing the development of drug efflux channels for clarithromycin and metronidazole used in the second phase. The aim of this prospective, randomized, controlled study was to investigate whether the efficacy of reverse sequential therapy was noninferior to sequential therapy in the treatment of H. pylori infection. Methods: From January 2009 to December 2010, consecutive H. pyloriinfected patients were randomly assigned to receive either sequential therapy (a 5-day dual therapy with pantoprazole plus amoxicillin, followed by a 5-day triple therapy with pantoprazole plus clarithromycin and metronidazole) or reverse sequential therapy (a 5-day triple therapy with pantoprazole plus clarithromycin and metronidazole, followed by a 5-day dual therapy with pantoprazole plus amoxicillin). H. pylori status was examined 6 weeks after the end of treatment by rapid urease and histology or urea breath test. Results: One hundred and twenty-two H. pylori-infected participants were randomized to receive sequential (n = 60) or reverse sequential therapy (n = 62). The eradication rates, by intention-to-treat analysis, were similar: 91.9% (95% confidence interval (CI): 85.1-98.7%) for sequential therapy and 96.7% (95% CI: 92.2-101.2%) for reverse sequential therapy (p = .44). Per-protocol analysis also showed similar results: 91.8% (95% CI: 84.9- 98.7%) for sequential group and 96.7% (95% CI: 92.2-101.2%) for reverse sequential therapy (p = .43). The two treatments exhibited comparable frequencies of adverse events (11.3% vs 6.7%, respectively) and drug compliance (98.4% vs 100%, respectively). The overall resistance rates of antibiotics were clarithromycin 10.5%, amoxicillin 0%, and metronidazole 44.2% of patients, respectively. The dual resistance rate of clarithromycin and metronidazole was 4.2%. Both therapies achieved a high eradication rate for clarithromycin-resistant strains (100% vs 100%, respectively) and metronidazole- resistant strains (81.8% vs 95%, respectively) by intention-to-treat analysis. Conclusions: Ten-day reverse sequential therapy and standard sequential therapy are equally effective for H. Pylori eradication. The finding indicates that the sequence of antibiotics administered in sequential therapy does not influence the efficacy of the treatment. [ABSTRACT FROM AUTHOR]

An efficient procedure is elaborated for the direct C-H allylation of imines (I) and different cyclic ketimines. [ABSTRACT FROM AUTHOR]

A useful method for the synthesis of ortho-olefinated ketimines from readily accessible cyclic N-sulfonyl ketimines and various olefins is presented. [ABSTRACT FROM AUTHOR]

The title compound, (C5H6N)4[SiMo12O40]·0.5H2O, was synthesized by a hydro­thermal method. The compound consists of a Keggin anion, [SiMo12O40]4−, disordered about a crystallographic centre of inversion, pyridinium cations, and a water mol­ecule lying on a mirror plane. The [SiMo12O40]4− anions and water mol­ecules lie in layers, and the pyridinium cations lie between these layers, forming N—H⋯O and C—H⋯O contacts to the O atoms of [SiMo12O40]4−. [ABSTRACT FROM AUTHOR]