Abstract We study the radial evolution of the inertial-range solar wind plasma turbulence and its anisotropy in the outer heliosphere. We use magnetic field ( B ) measurements from the Voyager 2 ...spacecraft for heliocentric distances R from 1 to 33 au. We find that the perpendicular and trace power spectral densities (PSDs) of the magnetic field ( E B ⊥ and E B Tr ) still follow a Kolmogorov-like spectrum until 33 au. The parallel magnetic field PSD, E B ∥ , transits from a power-law index of −2 to −5/3 as the distance crosses R ∼ 10 au. The PSD at frequencies 0.01 Hz < f < 0.2 Hz flattens at R > 20 au, gradually approaching an f −1 spectrum, probably due to instrument noise. At 0.002 Hz < f < 0.1 Hz, quasi-parallel propagation dominates at 1 au < R < 7 au, with quasi-perpendicular propagation gradually emerging at R > 5 au. For R > 7 au, oblique propagation becomes the primary mode of propagation. At smaller frequencies of f < 0.01 Hz, E B ⊥ increases with propagation angle at 1 au < R < 5 au, and in contrast decreases with propagation angle at R > 5 au due to the enhanced power level at propagation angles smaller than 20°. Such enhancement may derive from the injection of wave energy from the pickup ion source into the background turbulent cascade, and the injected wave energy is transferred across scales without leaving local enhancements in E B ⊥ or E B Tr .
Hard carbon (HC) is recognized as a promising anode material with outstanding electrochemical performance for alkali metal‐ion batteries including lithium‐ion batteries (LIBs), as well as their ...analogs sodium‐ion batteries (SIBs) and potassium‐ion batteries (PIBs). Herein, a comprehensive review of the recent research is presented to interpret the challenges and opportunities for the applications of HC anodes. The ion storage mechanisms, materials design, and electrolyte optimizations for alkali metal‐ion batteries are illustrated in‐depth. HC is particularly promising as an anode material for SIBs. The solid‐electrolyte interphase, initial Coulombic efficiency, safety concerns, and all‐climate performances, which are vital for practical applications, are comprehensively discussed. Furthermore, commercial prototypes of SIBs based on HC anodes are extensively elaborated. The remaining challenges and research perspectives are provided, aiming to shed light on future research and early commercialization of HC‐based SIBs.
Hard carbon (HC) is recognized as a promising anode material for alkali‐metal ion batteries, especially for sodium‐ion batteries (SIBs) which are cost effective for grid‐scale energy storage. This review aims for a comprehensive understanding of alkali‐metal ion storage mechanisms in HC, and also rational approaches to enhance the performance of HC anodes for practical SIBs.
•A research model is proposed to examine the factors that influence participation behavior of a customer in social commerce.•Social commerce intention is determined by customers’ virtual experiences, ...namely, social support, social presence and flow.•Customers’ virtual experiences are influenced by perceived interactivity, personalization and sociability features of the social commerce environment.•The results of the model tests using Renren and SinaWeibo samples are significantly different.
Social commerce, as a relatively new phenomenon, has attracted little research attention. This study aims to provide initial insights into the dynamics of customer participation in social commerce. Based on the stimulus–organism–response paradigm, this study develops a model to investigate the effects of technological features (perceived interactivity, perceived personalization and perceived sociability) of social commerce on customers’ virtual experiences (social support, social presence and flow) and subsequently their participation intention. The results indicate that social commerce intention is determined by social support, social presence and flow experiences. These experiences, in turn, are influenced by perceived interactivity, personalization and sociability features.
Users' continuance intention is vital to the future of micro-blogging service with rapid development and intensive competitions among its providers. This study examines how network externalities, in ...terms of perceived network size and perceived complementarity, enhance micro-blogging service users' perceived interactivity, and how such perception of interactivity, in turn, influences their satisfaction and continuance intention. Perceived interactivity contains four dimensions: control, playfulness, connectedness, and responsiveness. The results indicate that the four dimensions of perceived interactivity are significantly affected by perceived network size and perceived complementarity. Among the four dimensions of perceived interactivity, control, playfulness, and connectedness are positively related to micro-blogging service users' satisfaction, which further significantly impacts their continuance intention.
► Micro-blogging service users' satisfaction predicts continuance intention. ► Users' satisfaction is greatly explained by perceived interactivity. ► Both of direct and indirect network externalities affect perceived interactivity. ► Perceived interactivity comprises machine and social interactivity.
The insecticide exposure has been linked to Parkinson's disease (PD). In the present study, we used a most widely used cell line in study of PD, the SH-SY5Y cells, to investigate mechanisms of ...chlorpyrifos (CPF) induced cell toxicity and the possible roles of cell pyroptosis and oxidative stress in SH-SY5Y cells, as well as role of miR-181/SIRT1/PGC-1α/Nrf2 signaling pathway in this process.
SH-SY5Y cells were treated with different concentrations of CPF. Cell viability was measured using CCK-8 assay. Cell pyroptosis was determined by immunofluorescence of caspase-1 and TUNEL assay. The miR-181 (has-miR-181-5p) level was determined by qRT-PCR. Expression of SIRT1, PGC-1α, Nrf2, and pyroptosis related proteins NLRP3, caspase-1, IL-1β, and IL-18 was determined by both qRT-PCR and Western blotting.
Cell viability was found to be decreased with the increased CPF concentrations. The pyroptosis related proteins, ROS levels, as well as level of caspase-1 and the TUNEL positive cells were all significantly up-regulated by CPF. Meanwhile, expression of miR-181 and pyroptosis proteins was also enhanced, while the SIRT1/PGC-1α/Nrf2 signaling was inhibited by CPF. Knockdown of Nrf2 significantly up-regulated the expression of pyroptosis related proteins, ROS level, caspase-1, and the TUNEL positive cells, while over-expression of Nrf2 resulted in opposite results. The expression of PGC-1α and Nrf2 was significantly down-regulated when SIRT1 was inhibited, while over-expressed SIRT1 led to increased PGC-1α and Nrf2 levels. Besides, miR-181 promoted the CPF induced activation of pyroptosis and oxidative stress, as well as down-regulated SIRT1/PGC-1α/Nrf2 signaling, while inhibition of miR-181 led to opposite results.
Chlorpyrifos could inhibit cell proliferation, activate cell pyroptosis and increase susceptibility on oxidative stress-induced toxicity by elevating miR-181 through down-regulation of the SIRT1/PGC-1α/Nrf2 pathway in human neuroblastoma SH-SY5Y cells. This study might give deeper insights for mechanisms of CPF induced toxicity and might give some novel research targets for PD treatment.
Microplastic contamination in soil has received increasing attention since excessive plastic debris has been emitted directly into the terrestrial environment. Once released into the terrestrial ...environment, microplastics can be aged via photo- and thermally-initiated oxidative degradation, hetero-aggregation, and bioturbation. Aging affects the physiochemical properties of microplastics with the increase of surface roughness and oxygen-containing groups, which could enhance the sorption and mobility of microplastics in the soil and groundwater environment. However, the interactions among aging, sorption, and transport of microplastics in the terrestrial system have not been unveiled. This review clarifies the key processes of microplastics transport pathways in soil and groundwater ecosystems influenced by aging and sorption under various scenarios. Co-transport of microplastics and sorbed contaminants are also addressed to help understand the risks associated with heavy metals, organic contaminants, and engineered nanoparticles in the soil environment. Overall, this review elaborates the most pressing research limitations on the present literature and highlights the future perspectives to investigate the possible broad transport pathways of microplastics in soil.
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•Aging significantly changes physiochemical properties of microplastics.•The transport of aged microplastics was enhanced in the soil-groundwater environment.•Microplastics can co-transport with soil contaminants by serving as vectors.•Microplastics may transport into groundwater and thus increase the potential risk.
•Dairy manure biochar was more effective than rice husk biochar in removing Pb, Cu, Zn, and Cd.•Dairy manure biochar showed less competitive sorption of metals than rice husk biochar.•Precipitation ...with CO32- or PO43- was mainly responsible for the metal removal by the manure biochar.•Removal of metals by rice husk biochar was mainly due to their complexation with phenonic OH.
Rice husk biochar (RHBC) and dairy manure biochar (DMBC) were prepared as sorbents for simultaneously removing Pb, Cu, Zn, and Cd from aqueous solutions. DMBC was more effective in removing all the four heavy metals than RHBC, with the removal capacities of above 486mmolkg−1 for each metal, much higher than those of RHBC (65.5–140mmolkg−1). RHBC showed stronger competition for metal removal than DMBC when the four metals coexisted, with Pb the least affected and Cd the most inhibited. When each metal was 1mM in the multi-metal system, the metal removal by RHBC was reduced by 38.4–100%, much higher than that reduced by 2–40.9% for DMBC. The stronger competition for metals removal by RHBC was due to the fact that all metals competed only for the ionized phenolic-O− groups, while the removal of metals by DMBC resulted not only from the complexation with ionized hydroxyl-O− groups but also from the precipitation of metals with CO32- and/or PO43- that were rich in DMBC, resulting in less competition. The different mechanisms for the removal of metals by the two biochars were evidenced by the instrumental analysis of XRD, FTIR, and SEM as well as chemical modeling of Visual MINTEQ. Results indicated the waste biomass can be converted into value-added biochar as sorbents for removal of heavy metals and the removal ability varies with different biochar feedstock sources where the mineral components such as CO32-, PO43- originated from the feedstock play an important role in the sorption nature of biochar.
Biochar has been proven to possess the electron transfer property that can participate in the biogeochemical redox reaction in the environment. In this study, the electron accepting capacities (EACs) ...of the barley grass biochars produced at the various temperatures from 350 °C to 800 °C were investigated. The EAC values were in the range of 0.27–0.72 mmol e− (g biochar)−1 and showed increase as the pyrolysis temperature increased from 350 °C to 450 °C, slight decrease with temperature increasing from 450 °C to 500 °C, and then increase again from 650 °C to 800 °C. The O-containing groups were the EAC moieties identified by temperature programmed desorption coupled with mass spectroscopy (TPD-MS) and fourier transform infrared spectroscopy (FTIR) and carbonyl and quinone were the main EAC moieties, accounting for 75.4%–95.7% as the pyrolysis temperature increased from 350 °C to 800 °C. Overall, carbonyl and quinone determined the EACs properties of biochar which were affected by the pyrolysis temperature. The results will help us to develop biochar with controlled electron accepting property for specific environmental applications.
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•EAC of barley grass biochar was highly dependent on the pyrolysis temperature.•Carbonyl and quinone dominated the EAC of biochar at low and intermediate temperatures.•Quinone dominated the EAC of biochar at high temperatures.
•Feedstock and temperature influence specific biochar properties to a different extent.•Heterogeneity depended on feedstock and temperature were compared quantitatively.•Carbon sequestration, fixed C ...and minerals were determined by feedstock.•Biochar pH, specific surface area and recalcitrance were dominated by temperature.•Alkyl-C, aliphatic-C and aromatic-C were more highly related to temperature.
The aim of this study was to quantify the influence of the two main categories of factors determining the yield and properties of biochar, i.e., feedstock properties and production conditions, here represented by the highest treatment temperature (HTT). To achieve this, a wide range of production temperatures (200–650°C) and an extensive set of diverse feedstock (n=12) were used to calculate the sensitivity. The quantitative evaluation was based on statistical analysis of coefficients of variation, and thus derived indices representing the extent of influence of the two factors, i.e., a feedstock-depended heterogeneity (HF) and a temperature-depended heterogeneity (HT). The results showed that both feedstock properties and production conditions are important for determining the yield and properties of biochar, but their respective influence changes with the property or set of properties of interest. The biochar parameters most affected by feedstock properties were e.g., total organic carbon, fixed carbon, and mineral elements of biochar. On the other hand, biochar surface area and pH was mainly influenced by highest treatment temperature. Biochar recalcitrance was mainly determined by production temperature, while the potential total C sequestration (product of recalcitrance and pyrolysis carbon yield) depended more on feedstock. Overall, the work sheds some light on the relative importance of different biochar production process parameters on the final biochar product, which is an important step towards “designed” biochar.
Non-small cell lung cancer (NSCLC) is a common type of lung cancer, characterized by a poor prognosis. In the last several years, more and more studies have demonstrated the significant roles played ...by circular RNAs (circRNAs) in different human tumors progression including NSCLC. The present study was to explore the mechanism of hsa_circ_101237 in regulating non-small cell lung cancer (NSCLC). Totally 303 NSCLC cases were enrolled. A549 and H1299 cells were transfected. Cells viability, migration and invasion were determined by CCK-8 assay and transwell experiment, respectively. Luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay were performed. hsa_circ_101237, miR-490-3p and MAPK1 expression in tissues/cells were detected by qRT-PCR. The study found an elevation in the expression of Hsa_circRNA_101237 in both NSCLC tissues and cell line. High Hsa_circRNA_101237 expression predicted poor survival in NSCLC. Meanwhile, we found that hsa_circRNA_101237 expression sponged miR-490-3p to enhance MAPK1 expression, thus significantly promoting NSCLC cell lines proliferation, migration, and invasion. MAPK1 restoration prevented NSCLC cells proliferation, migration, and invasion to be repressed due to hsa_circRNA_101237 knockdown. To sum up, as revealed by the study, hsa_circRNA_101237 promoted the expression of MAPK1 via miRNA-490-3p sponge, thus affecting the NSCLC as an important onco-circRNA.
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