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The level of microplastics (MPs) in wastewater treatment plants (WWTPs) has been well evaluated by the particle number, while the mass concentration of MPs and especially nanoplastics (NPs) remains unclear. In this study, pyrolysis gas chromatography-mass spectrometry was used to determine the mass concentrations of MPs and NPs with different size ranges (0.01-1, 1-50, and 50-1000 μm) across the whole treatment schemes in two WWTPs. The mass concentrations of total MPs and NPs decreased from 26.23 and 11.28 μg/L in the influent to 1.75 and 0.71 μg/L in the effluent, with removal rates of 93.3 and 93.7% in plants A and B, respectively. The proportions of NPs (0.01-1 μm) were 12.0-17.9 and 5.6-19.5% in plants A and B, respectively, and the removal efficiency of NPs was lower than that of MPs (>1 μm). Based on annual wastewater effluent discharge, it is estimated that about 0.321 and 0.052 tons of MPs and NPs were released into the river each year. Overall, this study investigated the mass concentration of MPs and NPs with a wide size range of 0.01-1000 μm in wastewater, which provided valuable information regarding the pollution level and distribution characteristics of MPs, especially NPs, in WWTPs.

Nanoplastics (NPs) are currently considered an environmental pollutant of concern, but the actual extent of NP pollution in environmental water bodies remains unclear and there is not enough quantitative data to conduct proper risk assessments. In this study, a pretreatment method combining ultrafiltration (UF, 100 kDa) with hydrogen peroxide digestion and subsequent detection with pyrolysis gas chromatography-mass spectrometry (Py-GC/MS) was developed and used to identify and quantify six selected NPs in surface water (SW) and groundwater (GW), including poly(vinylchloride) (PVC), poly(methyl methacrylate) (PMMA), polypropylene (PP), polystyrene (PS), polyethylene (PE), and poly(ethylene terephthalate) (PET). The results show that the proposed method could detect NPs in environmental water samples. Nearly all selected NPs could be detected in the surface water at all locations, while PVC, PMMA, PS, and PET NPs were frequently below the detection limit in the groundwater. PP (32.9-69.9%) and PE (21.3-44.3%) NPs were the dominant components in both surface water and groundwater, although there were significant differences in the pollution levels attributed to the filtration efficiency of riverbank, with total mass concentrations of 0.283-0.793 μg/L (SW) and 0.021-0.203 μg/L (GW). Overall, this study quantified the NPs in complex aquatic environments for the first time, filling in gaps in our knowledge about NP pollution levels and providing a useful methodology and important reference data for future research.

Aims This study aimed to develop a nomogram model for predicting prolonged mechanical ventilation (PMV) in patients undergoing cardiovascular surgery. Methods and results In total, 693 patients undergoing cardiovascular surgery at an Affiliated Hospital of Nantong University between January 2018 and June 2020 were studied. Postoperative PMV was required in 147 patients (21.2%). Logistic regression analysis showed that delirium [odds ratio (OR), 3.063; 95% confidence interval (CI), 1.991–4.713; P Conclusion We established a new nomogram model that may provide an individual prediction of PMV. This model may provide nurses, social workers, physicians, and administrators with an accurate and objective assessment tool to identify patients at high risk for PMV after cardiovascular surgery.

In order to obtain comprehensive fuel consumption of parts and systems in the energy transmitting process of plug-in hybrid electric vehicles, this work carried out an experimental study on...

The transport and fate of nanoplastics (NPs) in aquatic environments are closely associated with their colloidal stability, which is affected by aging and natural organic matter (NOM) adsorption. This study systematically investigated the combined effects of photoaging and NOM (e.g. humic acids, HA; and a model protein, bovine serum albumin, BSA) on the aggregation kinetics of NPs (polystyrene, PS) in NaCl and CaCl2 solutions. Our results showed that photoaged NPs adsorbed less HA than pristine NPs due to weaker hydrophobic and π-π interactions. In return, HA showed weaker impacts on NPs’ stability after photoaging. Differently, photoaged NPs absorbed more BSA than pristine NPs due to stronger hydrogen bonding and electrostatic attraction. Thus, the inhibitory effects of BSA on the aggregation kinetics of NPs were enhanced after photoaging. Regarding the effects of NOM on the aging of NPs, our results showed that HA competed with NPs for photons and underwent photo-degradation. Subsequently, the destruction/reconstruction of adsorbed HA increased (in NaCl) or decreased (in CaCl2) the stability of NPs. Notably, light radiation-induced flocculation of BSA molecules, which wrapped and integrated NPs and lead to their destabilization. Overall, this study provided new insights into the aggregation behavior of NPs in aquatic systems, which have significant implications for predicting the transport and fate of NPs in complex real-world environments.

The aggregation and deposition behaviors of colloidal or dissolved black carbon (DBC) with coexisting heavy metals are important to understand the fate of DBC and the associated contaminants in environmental and engineering systems. Time-resolved dynamic light scattering (DLS) and quartz crystal microbalance with dissipation (QCM-D) techniques were employed to study the effect of cation concentration and properties on the aggregation and deposition behaviors of DBC with divalent heavy metals (Pb2+, Cu2+, Cd2+ and Zn2+). The aggregation experiments suggested that divalent heavy metals significantly destabilized DBC due to strong complexation and cation–π interaction, and the destabilization ability of these metal cations was related to their electronegativity (critical coagulation concentration (CCC): Pb2+ Cd2+ > Cu2+ > Zn2+). Overall, these results provide new insights into the aggregation and deposition behaviors of DBC with coexisting heavy metals in aquatic solution, which are helpful to understand the fate of DBC and the associated contaminants.

Dissolved black carbon (DBC), widely found in soil and water environments is likely to affect the transport of nanoplastics in aquatic environments. The aggregation and deposition behaviors of fresh and aged polystyrene nanoplastics (PSs) with and without DBC in NaCl solution were investigated by time-resolved dynamic light scattering (DLS) and quartz crystal microbalance with dissipation monitoring equipment (QCM-D) techniques. The results suggest that DBC can screen the surface charges of PSs by interacting with PSs through hydrogen bonding, hydrophobic interactions and π-π interactions, although they were negatively charged. DBC promoted the aggregation of PSs under relatively low ionic strengths, and it minimally affected the stability of PSs under high ionic strength. Deposition experiments showed that both DBC in salt solution and DBC adsorption on silica surface facilitated the deposition of fresh PSs while HA inhibited both deposition processes. After aging, PSs were more stable, and the effects of DBC and HA were weakened. This study investigated the influence mechanism of DBC on the aggregation and deposition behaviors, which provides new insights into the stability and transport of PSs in complex aquatic environments.

The oxidation of the toxic heavy metal thallium(I) (Tl(I)) is an efficient way to enhance Tl removal from water and wastewater. However, few studies have focused on the kinetics of Tl(I) oxidation in water, especially at environmentally relevant pH values. Therefore, the kinetics and mechanisms of Tl(I) oxidation by the common agents KMnO4 and HOCl under environmentally relevant pH condition were explored in the present study. The results indicated that the pH-dependent oxidation of Tl(I) by KMnO4 exhibited second-order kinetics under alkaline conditions (pH 8-10) with the main active species being TlOH, while the reaction could be characterized by autocatalysis at pH 4-6, and Mn(III) might also play an essential role in the MnO2 catalysis. Furthermore, a two-electron transfer mechanism under alkaline conditions was preliminarily proposed by using linear free energy relationships and X-ray photoelectron spectroscopy (XPS) analysis. Distinctively, the reaction rate of Tl(I) oxidation by HOCl decreased with increasing pH, and protonated chlorine might be the main active species. Moreover, the Tl(I)-HOCl reaction could be regarded as first order with respect to Tl(I), but the order with respect to HOCl was variable. Significant catalysis by MnO2 could also be observed in the oxidation of Tl(I) by HOCl, mainly due to the vacancies on MnO2 as active sites for sorbing Tl. This study elucidates the oxidation characteristics of thallium and establishes a theoretical foundation for the oxidation processes in thallium removal.

To investigate the effect of properties of carriers, environmental conditions and extracellular polymeric substances (EPS) on the initial adhesion of biofilm formation in biofilm-based reactors, a quartz crystal microbalance with dissipation (QCM-D) was applied to monitor the deposition rates and viscoelastic properties of sieved sludge particles on model biocarriers. The results suggested that surface charge, hydrophobicity and surface coating of five representative carriers influenced deposition rates and viscoelastic properties of biofilm, whose variation with NaCl concentrations was controlled by not only the Derjaguin-Landau-Verwey-Overbeek (DLVO) interaction but also non-DLVO forces. On hydrophobic surface, the addition of cationic substances enhanced the deposition rates and the compaction of deposited layer due to strong “hydrophobizing effect”. For examples, 10 mM Ca2+, 10 mM Mg2+ and 10 mg/L poly- l -lysine enhanced the deposition rates to nearly 3, 2 and 4 times, as well as reduced the softness of deposited layer to almost 35%, 60% and 35%. Conversely, 10 mg/L negatively charged alginate might cause water retainment and steric shielding, thereby reducing the deposition rates to 40% and increasing the softness of deposited film to 120%. The presence of EPS sub-fractions can modify surface properties of sludge particles, to distinct degrees, contributing to biofilm formation. Notably, compared to tightly bound EPS (TB-EPS), loosely bound EPS (LB-EPS) was more conducive to microbial attachment, but the presence of LB-EPS promoted the formation of a soft layer on a hydrophobic surface. Overall, these results provide insights into intrinsic mechanisms of the variation of deposition rates and viscoelastic properties responding to critical factors, which are meaningful to predict and regulate the initial adhesion process in biofilm-based reactors.

To understand the fate of colloidal or dissolved black carbon (DBC) in aquatic systems, a quartz crystal microbalance with dissipation (QCM-D) was applied to investigate deposition and release behaviors of DBC. The results suggested that DBC molecular composition and conformation were critical to the deposition processes on model surfaces, which were controlled by not only the classic Derjaguine-Landaue-Verweye-Overbeek (DLVO) interactions but also non-DLVO forces. The deposition rates of alumina, iron oxide and polyamide surfaces first increased due to the change of conformation and then decreased as the salt concentration increased. Correspondingly, the deposition layers first became more rigid and then got softer with the increase in the ionic strength. Both the pH values and calcium ion had distinctive effects on the deposition behaviors and viscoelastic properties due to their particular roles in DBC surface characteristic and molecular conformation. Overall, these results are meaningful to understand the environmental behaviors of DBC in aquatic systems.

The fuel consumption and efficiency properties of plug-in hybrid electric vehicles (PHEVs), which are becoming the most important means of transportation instead of fuel vehicles, are affected by component energy consumption in the power transmission process, causing global resources to be gradually wasted. To understand the influence of environmental temperature on steady-state and transient vehicle energy transmissions at different states of charge (SOCs), a complete energy flow test platform is designed, constructed and thoroughly explored to analyze the energy flow at different temperatures. These tests are carried out in a climate chamber to simulate real vehicle behavior with air conditioning on. The experimental results show that the engine efficiency is not relevant to the SOC. Moreover, it is found that the proportion of the total engine heat loss to the fuel energy is basically the same for all working conditions. However, the coolant loss ratio decreased with increasing SOCs. In addition, at a low SOC, the ratio of controller heat loss is not related to the increase in temperature. However, at a high SOC, this controller heat loss increases by 30 times. Therefore, the SOC is the major factor that affects generator loss.

The early stage of aggregation of cerium oxide nanoparticles (CeO

The early stage of aggregation of cerium oxide nanoparticles (CeO2 NPs) in anion solutions was inspected in the absence and presence of extracellular polymeric substance (EPS) with a help of time-resolved dynamic light scattering (DLS). The aggregation kinetics and attachment efficiencies were calculated according to measured hydrodynamic diameter across a range of 1–500 mM NaNO3 and 0.01–100. mM Na2SO4. The aggregation of CeO2 NPs in both NaNO3 and Na2SO4 solution conformed with the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory. In NaNO3 solution, the critical coagulation concentrations (CCC) of CeO2 NPs was calculated to be about 47 mM; in Na2SO4 solution, CeO2 NPs showed a re-stabilization process and thus there was no CCC value. SO42− had intenser effects on CeO2 NPs aggregation than NO3− might because of the distinction between their polarization, consisting in Hofmeister series. The presence of bound EPS (B-EPS), tightly bound EPS (TB-EPS) and loosely bound EPS (LB-EPS) in NaNO3 solutions all lead to significant decrease in CeO2 NPs aggregation. Steric repulsive force produced by absorbed EPS on CeO2 NPs might take main responsibility in stabilizing CeO2 NPs. Besides, Extended Derjaguin-Landau-Verwey-Overbeek (EDLVO) model successfully predicted the energy barrier between CeO2 NPs with B-EPS, TB-EPS and LB-EPS as a function of NaNO3 concentration. Furthermore, the difference in impeding the CeO2 NPs aggregation with B-EPS, TB-EPS and LB-EPS may be caused by the divergence in molecular weight and component mass fraction especially protein content. These results might subserve the assessment on the fate and transport behaviors of CeO2 NPs released in wastewater treatment plants.

Combining substructure theory, an efficient method for frequency response is formulated. The substructure method is confirmed feasible in a simple vehicle model by comparing with the road noise characteristics of substructure and standard method. And then, substructure models for body and chassis system are established respectively for a kind of actual vehicle with the problem of road noise. Subsequently, substructure method is employed to study road noise characteristics for the full vehicle model. In addition, the noise peaks of common characteristics are determined by comparing with simulation and test results, and the peaks are used as optimization objectives; the optimal Latin hypercube method is used to optimize the peaks until all the noise amplitudes of 40–200 Hz frequency band satisfy the target. Significantly, substructure method dramatically increases the optimization efficiency especially to bushing stiffness optimization schemes, the efficiency increases by 98%.

Engineered nanoparticles (ENPs) will inevitably enter wastewater treatment plants (WWTPs) due to their widespread application; thus, it is necessary to study the migration and transformation of nanoparticles in sewage treatment systems. Extracellular polymeric substances (EPSs) such as polysaccharides, proteins, nucleic acids, humic acids and other polymers are polymers released by microorganisms under certain conditions. Intracellular polymeric substances (IPSs) are microbial substances contained in the body with compositions similar to those of extracellular polymers. In this review, we summarize the characteristics of EPSs and IPSs from sewage-collecting microbial aggregates containing pure bacteria, activated sludge, granular sludge and biofilms. We also further investigate the dissolution, adsorption, aggregation, deposition, oxidation and other chemical transformation processes of nanoparticles, such as metals, metal oxides, and nonmetallic oxides. In particular, the review deeply analyzes the migration and transformation mechanisms of nanoparticles in EPS and IPS matrices, including physical, chemical, biological interactions mechanisms. Moreover, various factors, such as ionic strength, ionic valence, pH, light, oxidation-reduction potential and dissolved oxygen, influencing the interaction mechanisms are discussed. In recent years, studies on the interactions between EPSs/IPSs and nanoparticles have gradually increased, but the mechanisms of these interactions are seldom explored. Therefore, developing a systematic understanding of the migration and transformation mechanisms of ENPs is significant.

The aim of this study was to examine the effect of extracellular polysaccharide (PEP) from Antarctic bacterium Pseudoaltermonas sp. S-5 on RAW 264.7 cells together with the underlying signaling pathways. Our results illustrated that PEP induced dendritic-like morphological change in RAW 264.7 cells, and increased the productions of nitric oxide (NO) and tumor necrosis factor-α (TNF-α). PEP could also enhance phagocytic activity of RAW 264.7 cells. Results of immunofluorescence staining and immunoblotting indicated that PEP caused the nuclear translocation of nuclear factor (NF)-κB subunit p65, the degradation of IκB-α and up-expression of phosphorylated p38 mitogen-activated protein kinase (MAPK) in RAW 264.7 cells. According to pharmacological evaluation with specific enzyme inhibitors, both NF-κB and p38 MAPK signaling pathways were involved in the generation of NO and TNF-α induced by PEP. All these results indicated that PEP from Antarctic bacterium Pseudoaltermonas sp. S-5 activated RAW 264.7 cells through NF-κB and p38 MAPK signaling pathways.

Dendritic cells (DCs) are the key regulators of immune responses. In this study, the effect of an exopolysaccharide (EPS) from the culture broth of Trichoderma pseudokoningii on the phenotypic and functional maturation of murine DCs and its underlying molecular mechanisms were investigated. It showed that EPS induced the morphological changes of DCs and the enhanced expression of DCs featured surface molecules CD11c, CD86, CD80 and major histocompatibility complex II (MHC-II). Flow cytometry analysis showed that the treatment with EPS could reduce FITC-dextran uptake by DCs. Sequentially, the results of ELISA indicated that EPS could increase the production of interleukin-12p70 (IL-12p70) in culture supernatant of DCs. Immunofluorescence staining and western blot analysis further revealed that EPS significantly prompted nuclear factor (NF)-κB subunit p65 translocation, IκB-α protein degradation, and p38 mitogen-activated protein kinase (MAPK) phosphorylation. And the production of IL-12p70 was significantly decreased in condition of the inhibition of p38 or NF-κB signaling pathway. These findings suggested that EPS could induce DCs maturation through both p38 MAPK and NF-κB signaling pathways.

In this study, we reported the anticancer efficacy of exopolysaccharide (EPS) derived from Trichoderma pseudokoningii, on human breast cancer MCF-7 cells. Our results showed that EPS inhibited the proliferation of MCF-7 cells and induced lactic dehydrogenase release by inducing apoptosis and cell arrest at S phase. Further study revealed that EPS-induced apoptosis of MCF-7 cells was associated with alteration of nuclear morphology, disruption of mitochondrial membrane potential and accumulation of intracellular reactive oxygen species. Sequentially, EPS increased the activation of caspase-9 and caspase-3 in a dose-dependent manner; however, caspase-8 remained intact. Western blot analysis revealed that EPS increased the ratio of Bax/Bcl-2 and promoted the release of cytochrome c into the cytoplasm. Taken together, these findings provided evidence that EPS induced the apoptosis of MCF-7 cells through an intrinsic mitochondrial apoptotic pathway and that EPS may therefore be considered as an effective adjuvant agent against human breast cancer.

Exhaust model prediction based on local modeling method usually produces great error. To better predict hook model of vehicle condition, basic hook model of vehicle condition is established, and important corrections of hemming and baffle finite element (FE) models are carried out, as the real hook stiffness is the combination of hook body stiffness and its boundary stiffness. Model frequency response analysis is done on three hook examples which are directly connected to an exhaust muffler. Prediction results are in good agreement with the experiment results, and error is less than 0.6 %. The improved method is much more efficient in predicting the hook model of vehicle condition.

The aim of this study was to investigate the anticancer activity of exopolysaccharide (PEP) of Antarctic bacterium Pseudoaltermonas sp. S-5 and elucidate the underlying molecular mechanisms. PEP significantly inhibited the growth of human leukemia K562 cells. Results of morphological characterization showed that PEP-treated cells displayed typical morphological characteristics of apoptosis such as condensation of chromatin and formation of apoptotic bodies. Flow cytometry analyses and colorimetric assay demonstrated that PEP induced collapse of mitochondrial membrane potential and activation of caspase-9, which indicated that intrinsic apoptotic signaling pathway was involved in apoptosis induced by PEP in K562 cells. Western blot analysis showed that PEP increased the ratio of Bax/Bcl-2. In addition, calcium signal might contribute to the cytotoxicity of PEP against K562 cells. These findings suggest that PEP may be potentially effective drug against human leukemia.

Kinematic and Compliance (K&C) characteristics are the critical attribution to evaluate suspension performance. ADAMS-Car is a popular tool to simulate for suspension K&C characteristics simulation. Engineering experience has proved that even with all the component ratings as input, it is not guaranteed that the simulation could accord with physical testing, a lot of idealized simplification has their effects, e.g.: Difference on ride height, Friction, Hysteresis, Simplification of tyre mechanism, Assembly tolerance, Problem with small magnitude parameters. This paper will exemplify all this.

Experiments of laser transformation hardening were performed with various process parameters on the surface of ductile cast iron block, which is often used for vehicle body. The distribution of microhardness along the case depth direction and the variation of microstructure of hardened track were investigated. Wear test was carried out using a ball-on-flat-type wear-test machine. The results indicate that the hardened layers after the laser surface hardening treatment have excellence wear resistance. It is seen that the surface hardness of ductile cast iron blocks increases greatly at suitable values of process parameters in laser transformation hardening, which satisfies the vehicle dies.