Nanoscale zero-valent iron (nZVI) shows an excellent degradation effect on chlorinated contaminants in soil, but poses a threat to plants in combination with phytoremediation. Arbuscular mycorrhizal ...(AM) fungus can reduce the phyototoxicity of nZVI, but their combined impacts on polychlorinated biphenyls (PCBs) degradation and plant growth remain unclear. Here, a greenhouse pot experiment was conducted to investigate the influences of nZVI and/or Funneliformis caledonium on soil PCB degradation and ryegrass (Lolium perenne L.) antioxidative responses. The amendment of nZVI significantly reduced not only the total and homolog concentrations of PCBs in the soil, but also the ryegrass biomass as well as soil available P and root P concentrations. Moreover, nZVI significantly decreased leaf superoxide disutase (SOD) activity, while tended to decrease the protein content. In contrast, the additional inoculation of F. caledonium significantly increased leaf SOD activity and protein content, while tended to increase the catalase activity and tended to decrease the malondialdehyde content. The additional inoculation of F. caledonium also significantly increased soil alkaline phosphatase activity, and tended to increase root P concentration, but had no significantly effects on soil available P concentration, the biomass and P acquisition of ryegrass, which could be attributed to the fixation of soil available nutrients by nZVI. Additionally, F. caledonium facilitated PCB degradation in the nZVI-applied soil. Thus, AM fungus can alleviate the nZVI-induced phytotoxicity, showing great application potentials in accompany with nZVI for soil remediation.
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•Nanoscale zero-valent iron (nZVI) accelerated the degradation of soil PCBs.•nZVI aggravated oxidative stress and inhibited ryegrass growth.•AM fungus alleviated the phytotoxicity rather than P-limitation induced by nZVI.•AM fungus further enhanced PCB degradation in the nZVI-applied soil.•nZVI and AM fungus jointly facilitated phytoremediation of PCB-contaminated soils.
Previous meta-analyses that compared the outcome of SILC and CLC have not presented consistent conclusions. This meta-analysis was performed after adding many recent RCTs, to clarify this issue.
...Relevant articles published in English were identified by searching PubMed, Embase, Web of Knowledge, and the Cochrane Controlled Trial Register from January 1997 to February 2013. Reference lists of the retrieved articles were reviewed to identify additional articles. Primary outcomes (postoperative pain scores, cosmetic score, and length of incision) and secondary outcomes (operating time, blood loss, conversion rates, postoperative complications, postoperative hospital stay, time to initial oral intake, and time to resume work) were pooled. Quantitative variables were calculated using the weighted mean difference (WMD), and qualitative variables were pooled using odds ratios (OR).
25 appropriate RCTs were identified from 2128 published articles. 1841 patients were treated, 944 with SILC and 897 with CLC. SILC was superior to CLC in cosmetic score (WMD = 1.155, P<0.001), shorter length of incision (WMD = -3.285, P = 0.029), and postoperative pain within 12 h (VAS in 3-4 h, WMD = -0.704, P = 0.026; VAS in 6-8 h, WMD = -0.613, P = 0.010). CLC was superior to SILC in operating time (OT) (WMD = 13.613, P<0.001) and need of additional instruments (OR = 7.448, P<0.001). Other secondary outcomes were similar.
SILC offered a better cosmetic result and less postoperative pain for patients with uncomplicated cholelithiasis or polypoid lesions of the gallbladder. However, SILC was associated with a longer OT and required additional instruments.
Polycyclic aromatic hydrocarbons (PAHs) are considered to be persistent organic pollutants, which pose a great threat to human health and the surrounding environment. In order to explore the ...influence of informal electronic waste (e-waste) dismantling activities on inhabitants who live nearby, soil samples were collected from informal e-waste dismantling areas in Xinqiao, China and analysed for 16 United States Environmental Protection Agency (USEPA) priority PAHs. Results indicated that the 16 USEPA priority PAHs were found at all seven sampling locations. Sampling location 3, which was only 10 m away from a residential area, had 1053.69 μg kg−1 of PAHs and seriously exceeded the standard value specified by the Netherlands. The total percents of 4-ring and 5-ring PAHs accounted for 61.74 and 71.70%, respectively, indicating that most of the detected PAHs belonged to high-ring PAHs. The informal e-waste dismantling activities are the major sources of soil PAHs in Xinqiao. Furthermore, the concentration of seven carcinogenic PAHs was 114.76 μg kg−1 and represented a potential health risk to humans. Thereinto, benzoapyrene contributed the most, accounting for more than 50% in these locations. Our results may provide a reference about the influence of informal e-waste dismantling activities on the surrounding inhabitants and suggest that e-waste dismantling activities must be conducted in a formal enterprise which is far away from residential areas.
Cold cathode fluorescent lamps (CCFLs), with mercury as their essential component, were widely used as backlight in liquid crystal display (LCD) appliances before 2008. Since 2008, the mercury-free ...light emitting diode started to be used as a substitute for CCFLs and the replacement finished in about 2014. Nowadays, CCFLs are obsolete products from the viewpoint of manufacture but they are important as waste. In recent years, large amounts of CCFLs are flowing to waste phase for treatment and this has become a major issue in most countries. To better understand and control the risk of CCFLs, the stock of mercury in CCFLs, its flow to waste phase and mercury emission with the life cycle of CCFLs in mainland China were estimated in this study. Results showed that there was 15.2 tons of mercury stocked in CCFLs in main LCD appliances (i.e., LCD televisions, LCD monitors, and laptop monitors) from 2003–2015. CCFLs and mercury started to flow to waste phase around the year 2007 and will likely peak in 2018 with an annual flow of 324.8 million units and 1.5 tons respectively, then will likely decline dramatically till 2030. Dismantling and production were the two main life stages of CCFLs with mercury vapor release, during which approximately 2.1 tons and 1.2 tons of mercury were released to the atmosphere respectively. The research also indicates that mercury recycling in specialized facilities was another life stage with high mercury emission risk in which the processes of shredding, separation, and residue disposal are inevitably accompanied by mercury release.
A high concentration of potentially toxic elements (PTEs) can be frequently observed in the plastic processing sludge (PPS), thereby restricting its environmental applications. The main objective of ...this study was to investigate the effects of the co-pyrolysis of PPS and KH2PO4 (0, 5, 10 and 20 wt%) on the characteristics and environmental risks associated with the PTEs in PPS and derived chars. General characteristic analysis revealed that the char yield, ash content, pH, and particle size of the chars prepared with KH2PO4 were greater than those of the char prepared without KH2PO4 by 3.13–4.89 wt%, 2.95–4.4 wt%, 0.77–0.93, and 9.64–30.07 µm, respectively. The results of sequential extraction indicated that co-pyrolysis with KH2PO4 could considerably increase the distribution of PTEs in the F4 fraction (non-bioavailable) in PPS by 1.30–65.90% when compared with that obtained via co-pyrolysis with 5 wt% of KH2PO4. The toxic leaching tests indicated that the leaching concentrations of Cr, Ni, Cu, Zn, Cd, and Pb in the char prepared without KH2PO4 decreased to different extents when PPS was subjected to co-pyrolysis with KH2PO4, especially in case of co-pyrolysis with 5 wt% of KH2PO4. The range of decrease was 26.40–88.34%. However, in case of Cu, Zn, and Pb, the leaching concentration of the chars prepared with more than 10 wt% of KH2PO4 increased owing to the decomposition of (Cu Zn)PbVO4(OH) in an acidic environment. The results obtained using Hakanson’s equations revealed that the potential ecological risk associated with the PTEs in chars obtained by co-pyrolysis with KH2PO4 decreased, with a minimum decrease of 38.17%. In addition, the risk level associated with PPS reduced from considerable to low after co-pyrolysis with KH2PO4. The observations of this study imply that the co-pyrolysis of PPS with KH2PO4 can be a promising treatment for PTE immobilization.
•Co-pyrolysis of plastic processing sludge and different amount of KH2PO4 was studied.•Co-pyrolysis with KH2PO4 greatly increased stability of potentially toxic elements.•Cd contributed most to an ecological risk of plastic processing sludge and its chars.•Risk of plastic processing sludge decreased a lot after co-pyrolysis with KH2PO4.
As green solvents, ionic liquids (ILs) are quite suitable for the absorption of volatile organic compounds (VOCs) such as benzene and its homologues. However, solvent selection is the key to the VOC ...absorption process. In the present study, a rapid solvent screening tool, Conductor-like Screening Model for Real Solvents (COSMO-RS), was used to predict the solubility of toluene in 816 ILs. The effects of four structure characters, namely, the type and alkyl chain length of the cations and anions on the solubility of toluene were discussed. The following conclusions were drawn from the results: (1) ILs with pyrrolidinium-based cations showed better solubility than pyridinium- and imidazolium-based ones. (2) The solubility of toluene in PF6-based ILs increased with the increasing alkyl chain length, while its solubility in Ac-based ILs exhibited the opposite trend. (3) Toluene showed greater solubility in Cl-based ILs than those based on other anions. (4) The solubility of toluene increased with the anion alkyl chain length. Ac-based ILs were chosen as the most promising potential solvents, and further studied to determine the relationship between various interaction energy parameters and toluene solubility. The results showed that the misfit energy played a dominant role during the absorption process. Furthermore, several ILs were selected for experimental verification of the predicted solubility behavior using liquid and gaseous toluene. The results demonstrated that COSMO-RS could be used to semi-quantitatively and qualitatively predict the solubility of toluene, and this model had promising prospects in screening ILs for VOCs absorption. In summary, this study provided a fundamental basis and practical data for the control and treatment of VOCs.
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Intrahepatic cholangiocarcinoma (ICC) is an aggressive malignancy of the bile duct, representing the second most common primary liver cancer. Wntless (Wls) is a highly conserved transmembrane protein ...that shuttles palmitoylated Wnt proteins from the endoplasmic reticulum to the plasma membrane. Wls is highly expressed in various types of cancers and is essential for cell proliferation, anti-apoptotic activity, and survival. The profile of Wls expression and its clinical significance has not been well clarified in ICC. In the present study, we analyzed Wls expression in a set of ICC tissues (n = 44) by immunohistochemistry and the relationship between Wls expression and clinicopathological parameters. Immunoreactive Wls was detected in normal cholangiocytes, but was undetectable in normal hepatocytes. The intensity for immunoreactive Wls was varied, depending on ICC specimens. The degree of Wls expression was scored as 0 or 1+ in 8 specimens (18.2%), 2+ in 24 (54.5%), and 3+ in 12 (27.3%) out of the 44 ICC specimens, based on the staining intensity and percentage of Wls-positive cells. In normal cholangiocytes, the scores were varied from 0 to 2+. The intensity of Wls expression was positively associated with tumor stage (T stage, P = 0.005, r = 0.413), tumor-node-metastasis stage (TNM stage, P = 0.000, r = 0.548), and lymphatic invasion (P = 0.000, r = 0.548). Our results show that Wls is differentially expressed in ICC tissues and positively related to tumor stage and lymphatic invasion. Wls is a potential marker for advanced tumor stage and metastasis in ICC.
This study evaluates the efficiency of lead (Pb) extraction from lead bearing waste glass in strongly alkaline solution after mechanochemical reduction with iron. Less than 5% of the Pb can be ...leached directly by alkaline solution from the leaded glass. Compared with the non-activated leaded glass, the Pb extraction of leaded glass mechanically activated increased significantly. Around 67% of Pb was released after mechanical activation without iron, while more than 90% of Pb in the glass can be extracted after mechanochemical reduction with iron. The Pb-depleted solution can be recycled into the leaching step after Pb powder was obtained by electrowinning from the leaching solution. Thus, a novel hydrometallurgical process for recovering Pb from lead bearing waste glass in alkaline solution is proposed.
•It is very difficult to extract Pb from lead bearing waste glass as Pb atoms are fixed firmly in the glass network.•The Pb in leaded glass can be extracted in NaOH solution after mechanochemical reduction with metallic iron as additive.•The mechanochemical reduction process with iron follows the scheme: PbO3+Fe→Pbmod−O+FeO.•A novel hydrometallurgical process for recovering Pb from lead bearing waste glass in alkaline solution is proposed.
•AM fungi increases the number of Aphelenchoides sp. in soils with a range of As.•Aphelenchoides sp. promotes the development of mycorrhiza at the lowest As level.•Co-inoculation improves the growth ...and As uptake of plant at the lowest As level.•The grazing activity of fungivorous nematodes on AM fungi explains the results.
The effects of inoculation with two AM fungi (M1, Glomus caledonium; M2, Glomus spp. and Acaulospora spp.) and a fungivorous nematode Aphelenchoides sp. on growth and arsenic (As) uptake of Nicotiana tabacum L. were investigated in soils contaminated with a range of As. The reproduction of Aphelenchoides sp. was triggered by the co-inoculation of AM fungi regardless of AM fungal isolates and As levels. Stimulative effects of Aphelenchoides sp. on the development of mycorrhiza, slightly different between two AM fungi, were found particularly at the lowest As level. Irrespective of mycorrhizal inoculi, increasing soil As level decreased plant growth, but increased plant As uptake. Co-inoculation of AM fungi and Aphelenchoides sp. led plants to achieving further growth and greater As accumulation at the lowest As level. Results showed that the interactions between AM fungi and fungivorous nematodes were important in plant As tolerance and phytoextraction at low level As-polluted soil.
The developmental neurotoxicity caused by environmental pollutants has received great concern; however, there were still barely known about the underlying toxic mechanisms, especially the influence ...of varieties of regulatory factors such as microRNA (miRNA). A representative flame retardant, 2,2',4,4'-tetrabromodiphenyl ether (BDE47), was found to disrupt zebrafish development in visual perception and bone formation in previous study, thus here we investigated its effects on miRNA expression profiling of 6 days post fertilization (dpf) zebrafish larvae by deep sequencing. To overcome the shortage of zebrafish miRNA annotation, multiple data processing approaches, especially constructed network based on the interactions between miRNAs and enrichment terms, were adopted and helped us acquire several validated zebrafish miRNAs and two novel miRNAs in BDE47-induced effects, and identify corresponding biological processes of the miRNAs. Among them, miR-735 was supposed to play essential roles in larval sensory development according to analysis results. Our study also provided an effective strategy for analyzing biological effects on non-mammalian miRNAs with limited basic information.
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