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We commented on the empirical adjustment term recently introduced by Mellor. The purpose of the adjustment term is to include the effect of concentrating momentum at the surface, and the adjustment significantly improves the comparisons between modeled and measured velocity profiles. We found that the concentrating momentum from the adjustment term is largely overestimated relative to the commonly used parameterization approaches of concentrating momentum. The overestimated concentrating momentum leads to stronger velocity shear at the surface, which is partially canceled out by the vertical mixing caused by wave breaking. The model results also agree well with the measured velocity profiles if the fractions of the adjustment and the vertical mixing are simultaneously reduced. We also discussed an alternative method that includes the vertical radiation stress gradient term. The method exhibits no empiricism or uncertainty under the given wave conditions. [ABSTRACT FROM AUTHOR]

A simple, sensitive, and mild method for the determination of amino compounds based on a condensation reaction with fluorescence detection has been developed. 9-(2-Hydroxyethyl)acridone reacts with coupling agent N,N'-carbonyldiimidazole at ambient temperature to form activated amide intermediate 9-(2-acridone)oxyethylcarbonylimidazole (AOCD). The amide intermediate (AOCD) preferably reacts with amino compounds under mild reactions in the presence of 4-(dimethylamino)pyridine (base catalyst) in acetonitrile to give the corresponding sensitively fluorescent derivatives with an excitation maximum at [[lambda].sub.ex] 404 nm and an emission maximum at [[lambda].sub.em] 440 nm. The labeled derivatives exhibit high stability under reversed-phase conditions. The fluorescence intensities of derivatives in various solvents or at different temperatures were investigated. The method, in conjunction with a gradient elution, offers a baseline resolution of the common amine derivatives on a reversed-phase [C.sub.18] column. The LC separation for the derivatized amines shows good reproducibility with acetonitrile-water including 2.5% DMF as mobile phase. The relative standard deviations (n = 6) for each amine derivative are

Bemisia tabaci is a formidable insect pest worldwide, and it exhibits significant resistance to various insecticides. Dimpropyridaz is a novel pyridazine pyrazolecarboxamide insecticide used against sucking insect pests, but there is little information regarding its metabolic detoxification in arthropods or cross-resistance with other insecticides. In this study, we found that dimpropyridaz shows no cross-resistance with three other popular insecticides, namely abamectin, cyantraniliprole, and flupyradifurone. After treatment of B. tabaci adults with a high dose of dimpropyridaz, higher cytochrome P450 monooxygenase (P450) activity was detected in the survivors, and the expression of the P450 gene CYP6DW4 was highly induced. Cloning and characterization of the full-length amino acid sequence of CYP6DW4 indicated that it contains conserved domains typical of P450 genes, phylogenetic analysis revealed that it was closely related to a B. tabaci protein, CYP6DW3 , known to be involved in detoxification of imidacloprid. Silencing of CYP6DW4 by feeding insects with dsRNA significantly increased the susceptibility of B. tabaci to dimpropyridaz. In addition, homology modeling and molecular docking analyses showed the stable binding of dimpropyridaz to CYP6DW4 , with binding free energy of −6.65 kcal/mol. Our findings indicate that CYP6DW4 plays an important role in detoxification of dimpropyridaz and possibly promotes development of resistance in B. tabaci. [Display omitted] • Dimpropyridaz showed no cross-resistance to abamectin, cyantraniliprole, flupyradifurone. • High-dose selection of dimpropyridaz highly induced activity of P450 monooxygenase. • Knockdown of CYP6DW4 greatly increased mortality of B. tabaci to dimpropyridaz. • Dimpropyridaz could stably bind to CYP6DW4 in molecular docking. [ABSTRACT FROM AUTHOR]

Bemisia tabaci is a formidable insect pest worldwide, and exhibits significant resistance to various insecticides. Flupyradifurone is one novel butenolide insecticide and has emerged as a new weapon against B. tabaci , but field-evolved resistance to this insecticide has become a widespread concern. To unravel the mechanisms of field-evolved flupyradifurone resistance, we conducted a comprehensive investigation into susceptibility of twenty-one field populations within the Beijing-Tianjin-Hebei Region of China. Alarmingly, thirteen of these populations displayed varying degrees of resistance, ranging from low to medium levels, and building upon our prior findings, we meticulously cloned and characterized the CYP6CX4 gene in B. tabaci. Our investigations unequivocally confirmed the association between CYP6CX4 overexpression and flupyradifurone resistance in three of the thirteen resistant strains via RNA interference. To further validate our findings, we introduced CYP6CX4 overexpression into a transgenic Drosophila melanogaster line, resulting in a significant development of resistance to flupyradifurone in D. melanogaster. Additionally, homology modeling and molecular docking analyses showed the stable binding of flupyradifurone to CYP6CX4 , with binding free energy of −6.72 kcal mol−1. Collectively, our findings indicate that the induction of CYP6CX4 exerts one important role in detoxification of flupyradifurone, thereby promoting development of resistance in B. tabaci. [ABSTRACT FROM AUTHOR]

Underground coal gasification is an essential means of meeting the growing energy needs of some countries. In this paper, a new numerical simulation method of thermal-force-chemical-displacement multi-field coupling is developed, and in order to better adapt to the actual working conditions, taking Shanjiaoshu Coal Mine as the geological background, the first gasification working face of No. 12 coal seam is simulated based on the controlled retraction injection point technology. This method is used to simulate the heating of coal body by the ignition device at the initial stage of UCG, the chemical-thermal changes triggered by spontaneous combustion of the coal body under the continuous backward movement of the injection point, and the simulation of the formation of the cavity after the coal gasification reaction. Finally, the evolution of temperature and displacement fields in No.12 coal seam after gasification reaction is analyzed. Therefore, this study aims to simulate the actual working conditions more realistically, optimize the UCG technology, and produce more clean energy syngas to improve the energy situation in China. • A coupled thermal-force-chemical-displacement multi-field calculation of coal and surrounding rock strata. • Simulating of continuous movement of the gasification point to fit the actual process of CRIP. • The heat flowing into the model is calculated based on the chemical change. [ABSTRACT FROM AUTHOR]

Rock burst is one of the common disasters in the field of engineering. The traditional rock burst prediction model assumes that the data distribution is fixed or stationary and that the training samples are independent and identically distributed. The model is prone to catastrophic forgetting problems during use. In this study, a Bayesian model with incremental learning (IL) properties based on the Averaged One-Dependent Estimator (AODE) is proposed. The Tangential stress (σθ), Uniaxial tensile strength (σt), Uniaxial compressive strength (σc), Stress coefficient (σθ/σc), Brittleness coefficient (σc/σt), and elastic energy index (Wet) are taken as the study parameters. A total of 382 sets of rock burst data were used as research parameters for training and testing, including the elastic energy index Wet; Evaluate the overall performance of the model using an 8-fold cross-validation method. Finally, compare the model with intelligent algorithms such as naïve Bayes (NB), k-nearest neighbor (KNN), Artificial Neutral Network (ANN), quadratic discriminant analysis (QDA), and single indicator prediction methods. The results show that the prediction accuracy of the model reaches 92.9%, and it has excellent stability, applicability, and generalization ability. Compared with the two data inputs, the accuracy of the incremental learning attribute model improved by 10.8%. Compared with non-incremental learning models, the prediction accuracy of incremental learning models has increased by 6.4% and 13.9%, respectively. Compared with other rock burst prediction models, this model has significantly better prediction performance than other models. The model was applied to a tunnel on the CZ railway for engineering verification, and the accuracy of the prediction results reached 100%, proving that the model can continuously learn while ensuring high prediction accuracy. [ABSTRACT FROM AUTHOR]

A three-dimensional coupled wave-current model was employed to investigate the wave-induced longshore currents on barred beaches. The modeling system was developed by coupling the finite-volume community ocean model (FVCOM) and the simulating waves nearshore (SWAN) model to fully describe wave-current interactions in the nearshore region. The three-dimensional radiation stress, surface rollers and wave-enhanced turbulent mixing were incorporated as the major wave effects on currents. The model was first evaluated against data collected from multiple sets of laboratory experiments. Diagnostic simulations demonstrated that the contributions of the wave rollers and wave-induced mixing, in addition to the radiation stress, were important for ensuring accurate calculations. Then, the longshore current patterns on barred beaches were investigated through simulations of a series of test cases under controlled conditions. The cross-shore distribution of wave-induced longshore currents, which predominantly occurred within the barred beach surf zone, usually exhibited bimodal characteristics. The maximum peak longshore current velocity was positively correlated with the incident wave height and period. As the bar height and width increased, the first velocity peak of the longshore current strengthened, while the second peak weakened. In most cases, the maximum longshore current velocity on a barred beach coincided with the first peak, which could occur anywhere from the bar-trough region to the bar-crest region, depending on the wave and bar heights. This finding could be used to clarify the cross-shore location discrepancies in the maximum peak longshore current velocity reported in previously published studies. [Display omitted] • Wave-induced longshore currents on barred beaches are studied by a coupled model. • Surface roller and wave-enhanced mixing effects on longshore currents are important. • The longshore currents on barred beaches usually exhibit bimodal velocity profiles. • The first longshore velocity peak strengthens as the bar height and width increase. • Wave and bar heights significantly alter the peak longshore velocity location. [ABSTRACT FROM AUTHOR]