A simple and accurate method coupled with a gas chromatography-nitrogen phosphorus detector was developed to detect cyprodinil and fludioxonil in grape and soil. The accuracy and precision of the method in detecting the two fungicides were evaluated by conducting intra- and inter-day recovery experiments. The limits of detection were 0.017 mg/kg for cyprodinil and 0.030 mg/kg for fludioxonil. The limits of quantitation were 0.05 mg/kg for cyprodinil and 0.10 mg/kg for fludioxonil in grape and soil. The recoveries of the fungicides in grape and soil were investigated at three spiked levels and were found to range from 85.81 to 102.94% for cyprodinil and from 92.00 to 106.86% for fludioxonil, with relative standard deviations below 7%. Field experiments were conducted in two experimental locations in China. The half-lives of cyprodinil were 9.6-20.8 days in grape and 5.8-15.6 day in soil, and the half-lives of fludioxonil were 6.2-7.2 days in grape and 6.0-12.1 days in soil. When the cyprodinil and fludioxonil 62% water-dispersible granule formulation was sprayed at a low dosage three times, terminal residues of cyprodinil and fludioxonil were below 1.0 mg/kg in grape 14 days after harvest. This work may serve as a reference to establish the maximum residue limits for cyprodinil and fludioxonil in grape and promote the proper and safe use of these two fungicides.

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A pentadentate Schiff base bis(N-salicylidene)-3-oxapentane-1,5-diamine (H 2 L) and its lanthanide (III) complexes, [GdL(NO 3 )(DMF)(H 2 O)] (1) and [Dy 2 L 2 (NO 3 ) 2 ]·2H 2 O (2), have been synthesized and characterized by physical, chemical, and spectroscopic methods. Single crystal X-ray structure reveals that 1 is a discrete mononuclear species with nine-coordinate Gd(III) in a distorted monocapped square antiprism geometry. Complex 2 is a centrosymmetric binuclear neutral entity, in which Dy(III) is eight-coordinate in a distorted square antiprism. Electronic absorption titration spectra, ethidium bromide competitive experiments, and viscosity measurements indicate that both the ligand and complexes bind calf thymus DNA, presumably via groove binding. Investigations of antioxidant activities show that both complexes have some scavenging effects for hydroxyl and superoxide radicals.

Identifying protein-protein interactions (PPIs) is crucial to comprehend various biological processes in cells. Although high-throughput techniques generate many PPI data for various species, they are only a petty minority of the entire PPI network. Furthermore, these approaches are costly and time-consuming and have a high error rate. Therefore, it is necessary to design computational methods for efficiently detecting PPIs. In this study, a random projection ensemble classifier (RPEC) was explored to identify novel PPIs using evolutionary information contained in protein amino acid sequences. The evolutionary information was obtained from a position-specific scoring matrix (PSSM) generated from PSI-BLAST. A novel feature fusion scheme was then developed by combining discrete cosine transform (DCT), fast Fourier transform (FFT), and singular value decomposition (SVD). Finally, via the random projection ensemble classifier, the performance of the presented approach was evaluated on Yeast, Human, and H. pylori PPI datasets using 5-fold cross-validation. Our approach achieved high prediction accuracies of 95.64%, 96.59%, and 87.62%, respectively, effectively outperforming other existing methods. Generally speaking, our approach is quite promising and supplies a practical and effective method for predicting novel PPIs.

A modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the simultaneous determination of spirotetramat and its four metabolite residues in citrus, peel, pulp and soil was developed and validated by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The samples were extracted with acetonitrile (1%, glacial acetic acid, v/v) and purified using primary secondary amine and octadecylsilane. The limit of detection was 0.01-0.13 mg/kg, whereas that of quantification was 0.02-0.40 mg/kg for spirotetramat and its metabolites. The average recoveries of spirotetramat, spirotetramat-enol, spirotetramat-mono-hydroxy, spirotetramat-enol-glucoside and spirotetramat-ketohydroxy in all matrices were 73.33-107.91%, 75.93-114.85%, 76.44-100.78%, 71.46-103.19% and 73.08-105.27%, respectively, with relative standard deviations < 12.32%. The dissipation dynamics of spirotetramat in citrus and soil followed first-order kinetics, with half-lives of 2.3-8.5 days in the three sampling locations. The terminal residues of spirotetramat in four matrices at the three locations were measured below the 1.0 mg/kg maximum residue limit set by China, and residues were found to be concentrated on the peel. The risk assessment of citrus was evaluated using risk quotients. The risk quotient values were found to be significantly <1, suggesting that the risk to human health was negligible when using the recommended doses of spirotetramat in citrus. These results could provide guidance for the safe and proper application of spirotetramat in citrus in China.

Three new binuclear silver(I) complexes, namely, [Ag 2 (Meobb) 2 ](pic) 2 Á2H 2 O (1), [Ag 2 (Etobb) 2 (pic)](pic)Á(CH 3 CN)(2) and [Ag 2 (Bobb) 2 (pic) 2 ] (3) (Meobb = 1,3-bis(1-methylbenzimidazol-2-yl)-2-oxapropane, Etobb = 1,3-bis(1-ethylbenzimidazol-2-yl)-2-oxapropane, Bobb = 1,3-bis(1-benzylbenzimidazol-2-yl)-2-oxapropane, pic = picrate), have been synthesized and characterized by elemental analyses, IR spectroscopy and X-ray single crystal diffraction. Complex 1 displays an Ag 2 (Etobb) 2 dimeric structure. Each silver(I) ion is coordinated to two nitrogen atoms that adopt a distorted linear configuration. In complex 2, the coordination environment of silver(I) atoms is different. The Ag1 ion is coordinated in a T-shaped tri-coordinated geometry and the Ag2 is best described to be in a distorted tetrahedron. Complex 3 exhibits a discrete di-silver metallacyclic framework. One silver atom (Ag1) is present in a distorted tetrahedral geometry, whereas the other silver atom (Ag2) is five-coordinated with two nitrogen atoms, oxygen atoms and the Ag1 to form a distorted square-based pyramidal configuration. The interactions of the three complexes with calf thymus DNA (CT-DNA) has been investigated by electronic absorption titration, fluorescence spectroscopy and viscosity measurements, and the modes of CT-DNA binding to the complexes have been proposed.Experimental results suggest that the silver(I) complexes bind to DNA in an intercalation mode, and their binding affinity for DNA follows the order 1 4 2 4 3. The DNA-binding studies demonstrate that steric hindrance has a large influence on the binding ability to DNA. The complex that has smaller steric hindrance binds more strongly to DNA.

The paper proposes an adoption of slope, elevation, speed and route distance preview to achieve optimal energy management of plug-in hybrid electric vehicles (PHEV). The approach is to identify route features from historical and realtime traffic data, in which information fusion model and traffic prediction model are used to improve the information accuracy. Then, dynamic programming combined with equivalent consumption minimization strategy is used to compute an optimal solution for real-time energy management. The solution is the reference for PHEV energy management control along the route. To improve the system's ability of handling changing situation, the study further explores predictive control model in the realtime control of the energy. A simulation is performed to model PHEV under above energy control strategy with route preview. The results show that the average fuel consumption of PHEV along the previewed route with MPC strategy can be reduced compared with optimal strategy and base control strategy. Index Terms-Energy management, model predictive control (MPC), optimal control, plug-in hybrid electric vehicle (PHEV) This article has been accepted for publication in a future issue of this journal, but has not been fully edited. Content may change prior to final publication. Recommended by Associate Editor Xiangyang Zhao.

Aims. A stellar flare is a strong energy burst event. Understanding stellar flares is important for determining the properties of stellar magnetic activities. We aim to perform detailed statistical analyses on stellar flare characteristics in terms of the different stellar parameters using the light curves of the Transiting Exoplanet Survey Satellite (TESS) survey from July 2018 to October 2020. Methods. By using repeated fitting to differentiate stellar background light curves from flare events, we precisely detected 60 810 flare events on 13 478 stars from sectors 1–30 of the TESS data and determined the flare parameters. After cross-matching our samples with the Gaia survey, we obtained more stellar parameters to determine the relationship between flare parameters and stellar parameters. Results. The fraction of flaring stars decreases as stellar temperatures increase in the region of 2500–6500 K and stellar mass increases from 0.08 to 1.4 M⊙. The flare energies increase as the stellar temperature and the stellar mass decrease. There is a weak relationship between flare amplitude and Ro. We also confirm that M-type stars produce flares more frequently than F-, G-, and K-type stars. We find that the proportion of flaring stars increases from M0 to M5, and decreases from M5 to M7. We obtain a power-law index of 1.83 ± 0.15 for the cumulative flare frequency distribution. The index shows a decreasing trend from F- to K-type stars, and M-type stars rise for dwarf samples. The fraction of flaring stars decreases as the vertical absolute height increases in the range 0–200 pc but this fraction is stable in the range 200–800 pc. We find that eclipsing binary stars show more frequent flares than single stars.