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In traditional wastewater treatment methods, the removal of emerging contaminants including perfluorooctanoic acid (PFOA) can be challenging. To address this, biochar is commonly utilized as an activator for peroxymonosulphate (PMS) to effectively eliminate organic pollutants. Sewage sludge has shown potential as a biochar precursor, but its complex composition and variable iron content, as well as the low specific surface area of the product limit the practical use of iron-dominated sludge-derived catalysts. To overcome this limitation, N-doped citrate-sludge-derived carbon (NCSC) was synthesized, possessing a low iron content (0.29 at%) and a large specific surface area (315.31 m2 g−1). As a comparison, Fe-/N-doped citrate-sludge-derived carbon (Fe-NCSC) was prepared by introducing exogenous iron, resulting in a higher iron content (2.12 at%) but a significantly reduced specific surface area (73.87 m2 g−1). In performance evaluation, the NCSC/PMS system achieved impressive removal efficiency, effectively eliminating 99.8% of PFOA (at an initial concentration of 2 mg L−1) within 60 min, while Fe-NCSC/PMS only achieved 84.6%. The slightly lower reaction rate per specific surface area of NCSC/PMS proved that large specific surface area was NCSC's key advantage. The lower sensitivity of NCSC to pH and water substrates than FeNCSC suggested different activation mechanisms. Further analysis of reactive sites and species showed that the main oxidation mechanism of NCSC/PMS was forming the surface-bound PMS-NCSC complexes at the N sites, followed by PFOA donating electrons to the complexes to be oxidized, which was different from the Fe/N-dominated singlet oxygen mechanism of Fe-NSC/PMS. Furthermore, the reusability of the NCSC was demonstrated, with the removal rate decreasing to only 90.1% after four cycles and recovering to 94.8% after heated regeneration. In conclusion, this study provides a viable method for the elimination of emerging contaminants such as PFOA in water remediation. [Display omitted] • NCSC was facilely synthesized from excess activated sludge with low iron content. • The NCSC/PMS system removed 99.8% of PFOA within 60 min. • The large specific surface area was the key advantage of NCSC. • The N-dominated SMET mechanism in NCSC/PMS led to PFOA degradation. • PMS systems with NCSC and Fe-NCSC might have similar PFOA degradation pathways. [ABSTRACT FROM AUTHOR]

Highlights • A P2 hybrid powertrain model is built to support developing control strategy. • A multiphase control strategy is developed for different engine-start situations. • A nonlinear feedforward-feedback controller is designed for trajectory tracking. • Simulations and experiments have verified the developed control strategy. Abstract Instead of using conventional starter, engine can be started through slipping of the disconnect clutch in P2 hybrid automatic transmission. However, both riding comfort and engine-start time are challenges for control of the starting process. In order to achieve smooth and quick engine start, this paper proposed an optimized control strategy with respect to different engine-start situations. Firstly, a model of P2 hybrid powertrain is developed to characterize the transient behavior during engine start and provide support for developing control strategies. A multiphase control strategy is then proposed to cope with the control objective of either good riding comfort or short starting time depending on different driving situations. A nonlinear feedforward-feedback controller based on differential flatness and proportional-integral-derivative (PID) algorithm is developed to regulate the current of direct operating solenoid valve. Thus the pressure of the disconnect clutch can be fine-tuned and good tracking capability for the reference trajectory of engine speed can be realized. Finally, simulation and test results demonstrate that the proposed control strategy and controller can satisfy different requirements for engine start. Both riding comfort and engine-start time of a P2 hybrid vehicle can be effectively improved in the engine starting process. [ABSTRACT FROM AUTHOR]

Abstract: In order to improve the dispersion of detonation nanodiamonds (ND) in aqueous and non-aqueous media, a series of thermal treatments have been conducted in air ambient to modify ND surface. Small angle X-ray scattering (SAXS) technique and high resolution transmission electron microscopy (HRTEM) were introduced to observe the primary size of ND. Differential thermal analysis (DTA), X-ray diffraction (XRD) methodology, X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) spectroscopy were adopted to analyze the structure, bonds at surfaces of the treated ND. Malvern instrument Zetasizer3000HS was used for measuring the surface electric potential and the size distribution of ND. As thermal treatments can cause graphitization and oxidization of functional groups at the surface, ND treated at high temperature is correspondingly more negatively charged in an aqueous medium, and the increased absolute value of zeta potential ensures the electrostatic stability of ND particles. Specially, after being treated at a temperature more than 850K, ND can be well dispersed in various media. [Copyright &y& Elsevier]

• LPS-induced depression associates with increased CD38 levels in selected brain regions. • Inhibiting CD38 relieves depression-like behaviors via regulating neuroinflammation and synaptic function. • Inhibiting CD38 decreases excessive microglia activation via Sirt1-STAT3-NF-кB signaling pathway. • Neuronal activation in CA3 of hippocampus produces antidepressant effects. • The antidepressant effects of (R)-ketamine are related to decreased CD38 levels. CD38 is involved in immune responses, cell proliferation, and has been identified in the brain, where it is implicated in inflammation processes and psychiatric disorders. We hypothesized that dysfunctional CD38 activity in the brain may contribute to the pathogenesis of depression. To investigate the underlying mechanisms, we used a lipopolysaccharide (LPS)-induced depression-like model and conducted behavioral tests, molecular and morphological methods, along with optogenetic techniques. We microinjected adeno-associated virus into the hippocampal CA3 region with stereotaxic instrumentation. Our results showed a marked increase in CD38 expression in both the hippocampus and cortex of LPS-treated mice. Additionally, pharmacological inhibition and genetic knockout of CD38 effectively alleviated neuroinflammation, microglia activation, synaptic defects, and Sirt1/STAT3 signaling, subsequently improving depression-like behaviors. Moreover, optogenetic activation of glutamatergic neurons of hippocampal CA3 reduced the susceptibility of mice to depression-like behaviors, accompanied by reduced CD38 expression. We also found that (R)-ketamine, which displayed antidepressant effects, was linked to its anti-inflammatory properties by suppressing increased CD38 expression and reversing synaptic defects. In conclusion, hippocampal CD38 is closely linked to depression-like behaviors in an inflammation model, highlighting its potential as a therapeutic target for antidepressant development. [ABSTRACT FROM AUTHOR]

The multiframe super-resolution (SR) technique aims to obtain a high-resolution (HR) image by using a set of observed low-resolution (LR) images. In the reconstruction process, artifacts may be possibly produced due to the noise, especially in presence of stronger noise. In order to suppress artifacts while preserving discontinuities of images, in this paper a multiframe SR method is proposed by involving the reconstruction properties of the half-quadratic prior model together with the quadratic prior model using a convex combination. Moreover, by analyzing local features of the underlined HR image, these two prior models are combined by using an automatically calculated weight function, making both smooth and discontinuous pixels handled properly. A variational Bayesian inference (VBF) based algorithm is designed to efficiently and effectively seek the solution of the proposed method. With the VBF framework, motion parameters and hyper-parameters are all determined automatically, leading to an unsupervised SR method. The efficiency of the hybrid prior model is demonstrated theoretically and practically, which shows that our SR method can obtain better results from LR images even with stronger noise. Extensive experiments on several visual data have demonstrated the efficacy and superior performance of the proposed algorithm, which can not only preserve image details but also suppress artifacts. [ABSTRACT FROM AUTHOR]

The accurate effluent prediction plays a crucial role in providing early warning for abnormal effluent and achieving the adjustment of feedforward control parameters during wastewater treatment. This study applied a dual-staged attention mechanism based on long short-term memory network (DA-LSTM) to improve the accuracy of effluent quality prediction. The results showed that input attention (IA) and temporal attention (TA) significantly enhanced the prediction performance of LSTM. Specially, IA could adaptively adjust feature weights to enhance the robustness against input noise, with R2 increased by 13.18%. To promote its long-term memory ability, TA was used to increase the memory span from 96 h to 168 h. Compared to a single LSTM model, the DA-LSTM model showed an improvement in prediction accuracy by 5.10%, 2.11%, 14.47% for COD, TP, and TN. Additionally, DA-LSTM demonstrated excellent generalization performance in new scenarios, with the R2 values for COD, TP, and TN increasing by 22.67%, 20.06%, and 17.14% respectively, while the MAPE values decreased by 56.46%, 63.08%, and 42.79%. In conclusion, the DA-LSTM model demonstrated excellent prediction performance and generalization ability due to its advantages of feature-adaptive weighting and long-term memory focusing. This has forward-looking significance for achieving efficient early warning of abnormal operating conditions and timely management of control parameters. [Display omitted] • Improving prediction accuracy of effluent quality in multivariate time series. • Dynamically adjusting feature weights and selecting critical features. • Adaptively focusing on historical information and enhancing long-term memory. • Outstanding generalization performance in novel scenarios. [ABSTRACT FROM AUTHOR]

• A comprehensive dynamic model of PGS is established for planet bearing dynamics. • Planet bearing dynamics are studied under RRC, especially for roller-cage impact. • A trap of the roller into the cage pocket under RRC is observed and clarified. • Influences of clearances and revolution speed on bearing dynamics are analyzed. The planet bearing has become the component most likely to fail in the planetary gear set (PGS), especially for the revolution-rotation coupled (RRC) condition. However, the dynamics of the planet bearing in the PGS are still not revealed yet. To address it, this paper proposes a comprehensive dynamic model of the PGS, in which the gear mesh and roller contact excitations, as well as the centrifugal and Coriolis effect, are considered. On this basis, the dynamics of the planet bearing are investigated, particularly for the roller-cage contact. The results show that significant impacts between the roller and the cage would occur under RRC conditions and increase with the revolution speed. The most critical factor determining the roller-cage impact force is the revolution centrifugal force of the roller. The radial and cage pocket clearances show less effect but can still influence the roller-cage impact force. [ABSTRACT FROM AUTHOR]

This study proposes an efficient method for the evaluation of vibrations and buckling in thin-walled beams with complex geometries subjected to progressive compressive loads. A comprehensive study is conducted in order to investigate the effects of compressive loads on the natural frequencies of the thin-walled beams. Namely, a numerical simulation of the Vibration Correlation Technique is provided in this study. Finite Elements (FEs) are built in the framework of the Carrera Unified Formulation (CUF), and the displacements of complex geometric shapes of the thin-walled beams are evaluated using low- to higher-order Taylor and Lagrange polynomials. The results are compared with the experimental results of the available literature and the numerical results by the shell models. The cross-sectional deformations of the beam due to the vibration modes are also compared, and the importance of structural theories capable of accurate detection of complex cross-sectional deformations is highlighted. The obtained results are demonstrated to be promising and accurate and match reasonably well with the experiments and shell models, which are more expensive in terms of computational costs compared to the efficient CUF ones proposed here. [ABSTRACT FROM AUTHOR]

• The dynamic characteristic of wet clutch actuating system is analyzed. • Three types of speed deviations occurring in clutch filling process are analyzed. • An adaptive iterative control strategy for the wet-clutch filling process is proposed. • A double-input-and-double-output fuzzy logic controller (DIDO-FLC) is designed. • The vehicle test is performed to validate the proposed control strategy. In the gear shifting processes of an automatic transmission (AT), fast and smooth transitions between different gears without drivetrain jerking are always expected, which leads to a desire for high-quality clutch-to-clutch shifts. The accurate and effective filling control of clutches is the base for achieving desirable clutch-to-clutch shifts. This study focuses on developing an adaptive fuzzy iterative control strategy for the filling process of wet clutches in ATs. Firstly, a specific structure and dynamic characteristics of the wet clutch actuating system is analyzed to assist in the designing of control strategies. Afterwards, three types of deviations that usually occur in the filling process, named as speed drop, clutch tie-up and engine flare respectively, are defined and analyzed according to their different characteristics. The adaptive control strategy is then developed to realize the reduction of the deviations. The concrete adjustment performed by the control strategy is based on the features of the previous deviations during the adaptive iteration. Moreover, a double-input-and-double-output fuzzy logic controller (DIDO-FLC) is designed and introduced in the control strategy, which can adjust the fast filling time and the maximum fast filling pressure of the clutch simultaneously. In order to validate the proposed strategy, the results of vehicle test are presented, which demonstrate that the deviations are effectively diminished and the shifting quality is obviously improved. [ABSTRACT FROM AUTHOR]

In a previous study, when resistant tomato plants (cv. Motelle) carrying the Sm gene were challenged with S. lycopersici , the SLNLC1 gene was significantly upregulated. In this study, to verify the function of the SLNLC1 gene response to disease resistance against S. lycopersici , virus-induced gene silencing (VIGS) was used to downregulate the expression level of the SLNLC1 gene in resistant tomato plants inoculated with S. lycopersici . After inoculation with S. lycopersici , a susceptible phenotype was observed in the silenced SLNLC1 -resistant plants. Through microscopy, impaired hypersensitive response (HR) and decreased ROS accumulation were also observed in the silenced SLNLC1 plants. In addition, the production of lignin and callose were decreased in the silenced SLNLC1 plants. Taken together, these results indicated that silencing the SLNLC1 gene attenuated the resistance of tomato plants resistant to S. lycopersici. [ABSTRACT FROM AUTHOR]

S-adenosylmethionine decarboxylase (SAMDC) is a key enzyme in polyamine (PA) biosynthesis, and overexpression of SAMDC in plants can increase the PA level and enhance tolerance to multiple abiotic and biotic stresses. In our previous study, this gene was significantly up-regulated during Cladosporium fulvum resistance gene ( Cf )/ Avirulence ( Avr ) interaction in tomato. In this study, to further understand the role that the SAMDC gene plays in Cf / Avr interaction, the virus-induced gene silencing (VIGS) method was applied to down-regulate SAMDC expression in CGN18423, a line carrying the Cf-19 gene for resistance to C. fulvum . Then, these plants were infected with C. fulvum to analyze changes in resistance. The silencing of SAMDC was confirmed by quantitative real-time PCR (qRT-PCR) analysis and PA quantification. The resistance levels of SAMDC -silenced plants were lower than those of untreated CGN18423 plants. No visible signs of infection were observed on the leaves of untreated CGN18423 plants, while some small chlorotic spots were observed on parts of the leaf margins of SAMDC -silenced plants, and hyphae inside the chlorotic spots were observed late in the hypersensitive response (HR) process. These changes suggested that silencing of the SAMDC gene affected the process of Cf/Avr interaction and decreased the resistance of CGN18423 to C. fulvum . [ABSTRACT FROM AUTHOR]

Aerobic granular sludge (AGS) technology has been widely studied as "The Next Generation Wastewater Treatment technology". The effect of hydraulic conditions on the structural stability of AGS has been widely studied. However, the function of flow regime on the AGS stability, especially dissolved oxygen (DO) mass transfer, is still unknown. In this study, we used the Reynolds number (Re) to quantify the flow regime and selected different stages of AGS as experimental subjects. Results showed that the relatively suitable Re (Re = 150) could create lower DO mass transfer limitation (Lc = 27.4 μm) and increase protein (PN) contents and the abundance of hydrophobic functional groups in AGS. At this condition (Re = 150), the interfacial Gibbs free energy of sludge-water (Δ G L S a) was at a lower state (−129.75 ± 2.15 mJ·m−2), which favored the stability of AGS. Principal component analysis (PCA) and correlation analysis indicated that the response of Δ G L S a was affected by Lc, PN, and hydrophobic groups. In addition, results obtained for unstable AGS further verified that suitable Re regulates the structural stability of AGS. This study deepens the understanding of Re as an important hydraulic parameter for structural stability of AGS, which is also of great significance for energy saving of sequential batch reactors (SBRs) with agitation in practical engineering. [Display omitted] • The stability of AGS was studied by combining Re and thermodynamics (Δ G L S a). • PN had a strong correlation with Lc and Δ G L S a in stable AGS. • Lower Re provided a theoretical foundation for energy saving. [ABSTRACT FROM AUTHOR]

Interfacial Gibbs free energy (IGFE) as a thermodynamic indicator characterize the stability of the natural system. For aerobic granular sludge (AGS), how IGFE determines the stability of sludge remains to be determined. The Gibbs free energy change at the AGS-water interface (Δ G s w a) and AGS interfaces (Δ G s c) were selected as the main interfacial thermodynamic factors. Results indicated that the stable AGS was guaranteed with Δ G s c at the range of −31 to - 46 J m−2. Pearson correlation coefficients between Δ G s w a / Δ G s c and relative hydrophobicity, water content, SVI 30 , integrity coefficient were −0.9, 0.8, 0.85, and 0.84, which illustrated that the IGFE could be a more comprehensive thermodynamic indicator. Microbial community and EPS analysis verified the importance of denitrifiers, Amide III, protein-like substances for AGS stability. This work offers a new insight into the development of AGS stability based on IGFE. [Display omitted] • The interfacial Gibbs free energy of stable AGS maintained at a certain range. •ΔGswa / Δ G s c had a strong correlation with stability characteristics of sludge. • Surface properties played an important role in interfacial thermodynamic state. [ABSTRACT FROM AUTHOR]

Tomato leaf mold is an important disease caused by Cladosporium fulvum . The Cf -19 gene, which has been shown to confer resistance to this disease in the field, can serve as a new candidate gene in breeding, but the lack of understanding about this gene restricts its application. In this study, we utilized the cDNA-AFLP technique combined with bulk segregant analysis (BSA) to isolate tomato genes related to the Cf -19-mediated resistance response. Twenty-six differentially expressed transcript-derived fragments (TDFs) were successfully isolated based on four expression patterns. Expression patterns of six TDFs were further investigated by qRT-PCR, and the results were consistent with the results of the cDNA-AFLP analysis. Most of the genes detected by transcript profiling of the Cf -19-mediated defense response showed similar expression patterns in the Cf -4 and Cf -9-mediated defense responses. Two genes, SAMDC (TDF35) and Eli3 (TDF49), were first detected in the Cf / Avr interaction. TDF16 showed similarity with a receptor-like protein and the gene cluster Hcr 9 where Cf -4 and Cf -9 were located. The genes detected in this study may play important roles in Cf -19-mediated resistance response. [ABSTRACT FROM AUTHOR]

Aerobic granular sludge (AGS) has excellent performance in wastewater treatment. However, the formation and mechanism of AGS by effluent reflux are not fully understood in sequential batch reactors (SBRs). In this study, two reactors were constructed, among which R1 was the control group, and the R2 reactor refluxed one-fourth of the supernatant of the effluent to the influent water. In the reactor of R2, the granules had better COD and TN removal efficiencies and resistance to external shocks, and AGS produced more extracellular polymeric substances (EPS). Analysis of microbial community indicated that AHLs-mediated microbes, denitrifying microbes, and EPS producers were enriched. At the same time, the correlation between 3OC6-HSL, C8-HSL, C12-HSL and PN was 0.89*, 0.94** and 0.92* respectively, the possible mechanism of enhanced granulation was mainly the promotion of AHLs by effluent reflux. Therefore, the effluent reflux strategy could be an innovative and sustainable strategy that validates the function of AHLs-mediated QS to accelerate aerobic sludge granulation and maintain its structural stability. [Display omitted] • The effluent reflux enhancing the aerobic granulation was first investigated. • AHLs-mediated microbes, denitrifying microbes and EPS producers were enriched. • 3OC6-HSL, C8-HSL and C12-HSL had a strong correlation with PN. [ABSTRACT FROM AUTHOR]