Perfluoroalkyl and polyfluoroalkyl substances (PFASs) have gained increasingly global attention in recent years. Due to their unique amphiphilic properties and stability, PFASs are recognized as ...highly persistent, toxic, and environmentally bioaccumulative. Among several physicochemical technologies, adsorption has been extensively used and proved to be an effective method for removing PFASs from aqueous environment. In this review article, the technical feasibility of the use of different adsorbents, such as activated carbon, ion exchange resins, minerals, molecularly imprinted polymer (MIP), carbon nanotubes (CNTs), and a wide range of potentially low-cost biosorbents, for PFASs removal from water or wastewater is critically reviewed. The evaluation and comparison of their PFASs sorption behavior in terms of kinetics and isotherms is presented. The mechanisms involved in PFASs adsorption processes, such as diffusion, electrostatic interaction, hydrophobic interaction, ion exchange and hydrogen bond, are discussed. The effects of the parameters variability on sorption process are highlighted. Based on the literature reviewed, a few recommendations for future research on PFASs adsorption are also elaborated.
Capsule: The adsorption behavior and mechanisms of perfluoroalkyl and polyfluoroalkyl substances (PFASs) on various adsorbents are reviewed.
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•Resins and CNTs exhibit higher adsorption capacity than other adsorbents.•Biosorbents have great potential for efficient PFAS removal with cost-effectiveness.•Adsorption mechanisms involve electrostatic interaction, hydrophobic interaction and ion exchange.•The environmental parameters can influence PFASs adoption performance.
Abstract
Topological superconductors (TSCs) are unconventional superconductors with bulk superconducting gap and in-gap Majorana states on the boundary that may be used as topological qubits for ...quantum computation. Despite their importance in both fundamental research and applications, natural TSCs are very rare. Here, combining state of the art synchrotron and laser-based angle-resolved photoemission spectroscopy, we investigated a stoichiometric transition metal dichalcogenide (TMD), 2M-WS
2
with a superconducting transition temperature of 8.8 K (the highest among all TMDs in the natural form up to date) and observed distinctive topological surface states (TSSs). Furthermore, in the superconducting state, we found that the TSSs acquired a nodeless superconducting gap with similar magnitude as that of the bulk states. These discoveries not only evidence 2M-WS
2
as an intrinsic TSC without the need of sensitive composition tuning or sophisticated heterostructures fabrication, but also provide an ideal platform for device applications thanks to its van der Waals layered structure.
Summary
Background
Helicobacter pylori infection is a worldwide threat to human health with recurrence rates that vary widely. The precise correlation between H. pylori recurrence and socioeconomic ...development has not been determined.
Aim
To determine H. pylori recurrence rates after successful eradication and their association with socioeconomic development metrics.
Methods
Bibliographical searches were performed in the MEDLINE database. We reviewed all results, filtered by inclusion criteria, extracted primary results to calculate H. pylori recurrence rates and calculated national Human Development Index (HDI) values for the periods during which the studies were conducted.
Results
One thousand two hundred and twenty six cases of H. pylori recurrence in 77 eligible studies were observed in 43 525.1 follow‐up patient‐years after successful eradication therapy, giving a recurrence rate of 2.82 ± 1.16% per patient‐year (weighted mean ± 95% confidence interval). H. pylori recurrence rate was inversely correlated with national HDI on linear (r = −0.633) and weighted least square (r = −0.546) regression analysis. Countries with very high HDI had a mean recurrence rate significantly lower than that of high, medium and low HDI countries (P < 0.01, 0.001, and 0.001, respectively).
Conclusions
Less‐developed areas, as measured by HDI, are more likely to have high H. pylori recurrence rates. A different approach to follow‐up after H. pylori eradication is needed in developing countries where reinfection is highly prevalent, paying special attention to sources of reinfection and high‐risk groups.
Hepatocellular carcinoma (HCC) is one of the leading malignancies worldwide. Myocyte enhancer factor 2C (MEF2C) was traditionally regarded as a development-associated factor and was recently reported ...to be an oncogene candidate. We have previously reported overexpression of MEF2C in HCC; however, the roles of MEF2C in HCC remain to be clarified. In this study, HCC cell lines and a xenograft mouse model were used to determine the functions of MEF2C in vitro and in vivo, respectively. Specific plasmids and small interfering RNA were used to upregulate and downregulate MEF2C expression, respectively. Functional assays were performed to assess the influence of MEF2C on cell proliferation, and VEGF-induced vasculogenic mimicry, migration/invasion as well as angiogenesis. Co-immunoprecipitation was conducted to identify the interaction of MEF2C and β-catenin. Human HCC tissue microarrays were used to investigate correlations among MEF2C, β-catenin and involved biomarkers. MEF2C was found to mediate VEGF-induced vasculogenic mimicry, angiogenesis and migration/invasion, with involvement of the p38 MAPK and PKC signaling pathways. However, MEF2C itself inhibited tumor growth in vitro and in vivo. MEF2C was upregulated by and directly interacted with β-catenin. The nuclear translocation of β-catenin blocked by MEF2C was responsible for MEF2C-mediated growth inhibition. The nuclear translocation of MEF2C was associated with intracellular calcium signaling induced by β-catenin. HCC microarrays showed correlations of nuclear MEF2C with the angiogenesis-associated biomarker, CD31, and cytosolic MEF2C with the proliferation-associated biomarker, Ki-67. MEF2C showed double-edged activities in HCC, namely mediating VEGF-induced malignancy enhancement while inhibiting cancer proliferation via blockade of Wnt/β-catenin signaling. The overall effect of MEF2C in HCC progression regulation was dictated by its subcellular distribution. This should be determined prior to any MEF2C-associated intervention in HCC.
An anaerobic kraft lignin (KL)‐degrading bacterial strain was isolated from sludge of a pulp and paper mill. It was characterized as Acetoanaerobium sp. WJDL‐Y2 by 16S rRNA gene sequencing. The ...maximum KL degradation capability of strain Y2 was determined to be 24·9% on a COD basis under an optimal condition with temperature of 31·5°C, initial pH of 6·8 and KL to nitrogen (as NH₄Cl) ratio of 6·5 by mass. Growth kinetic studies showed that the KL tolerance of strain Y2 was relatively high (Kᵢ = 8120·45 mg l⁻¹). Analysing KL degradation products by GC‐MS revealed the formation of low‐molecular‐weight aromatic compounds (LMWACs), including benzene‐propanoic acid, syringic acid and ferulic acid. This indicates that strain Y2 can oxidize lignin structure's p‐hydroxyphenyl (H) units, guaiacyl (G) units and syringyl (S). In addition, the inoculated sample also contained low‐molecular acid compounds, such as hexanoic acid, adipic acid and 2‐hydroxybutyric acid, further validating strain Y2's ability to degrade KL. SIGNIFICANCE AND IMPACT OF THE STUDY: Kraft lignin containing effluents discharged from pulp and paper industries causes serious environmental pollution in developing countries. Due to the immense environmental adaptability and biochemical versatility, bacterial ligninolytic potential deserve to be studied for application in effluent treatment of pulp and paper industry. In this study, an anaerobic lignin‐degrading bacterium, Acetoanaerobium sp. WJDL‐Y2 (accession no. KF176997),was isolated from the sludge of a pulp and paper mill. Strain Y2 can play an important role in treating pulp and paper wastewater, as well as breaking down materials for biofuel and chemical production.
Novel tough bio-based polyesters poly(ethylene 1,5-thiophenedicarboxylate-co- 1,4-cyclohexanedimethylene 1,5thiophenedicarboxylate)s (PECTFs) were synthesized from 1,5-thiophenedicarboxylic acid ...(TDCA), 1,4-cyclohexanedimethanol (CHDM) and ethylene glycol (EG). The microstructure, thermal and mechanical properties were investigated. Poly(ethylene 1,5-thiophenedicarboxylate) (PETF) displayed the glass transition temperature (~64°C) and tensile strength (~71 MPa) similar to poly(ethylene terephthalate) (PET). However, the nonlinear structure of TDCA resulted in an angle of 148° between carboxylic acid carbons and the S atom resulted in a permanent dipole, so the thiophene ring-flipping was hindered and the low elongation at break (~14%) was observed for PETF. The peak corresponding to the secondary relaxation shifted to lower temperature due to the incorporation of CHDM, which yielded ductile copolyesters with high elongation at break. When the CHDM content was equal to or higher than 19%, a high elongation at break (>160%) was observed.
Blood-circulating microRNAs (miRNAs) have been reported to be used as potential biomarkers in various cancers. MiR-101 has been found to act as a tumor suppressor in many tumor types, but little is ...known for osteosarcoma. The purpose of this study was to investigate miR-101 expression in osteosarcoma patients and assess its correlation with clinical features and prognosis. Serum samples from 152 osteosarcoma patients and 70 healthy controls were detected using quantitative reverse-transcription polymerase chain reaction (qRT-PCR). The data showed that miR-101 expression levels were remarkably underexpressed in serum samples from osteosarcoma patients compared to controls, and the post-treatment serum miR-101 expression was significantly higher than that in the pre-treatment expression. Low serum miR-101 expression was positively associated with advanced clinical stage and distant metastasis. Receiver operating characteristic (ROC) curve analysis showed that serum miR-101 could serve as a useful marker for osteosarcoma diagnosis, with a high sensitivity and specificity. Moreover, patients with high miR-101 expression had longer overall survival and recurrence free survival than those with low miR-101 expression. In addition, both univariate and multivariate analyses showed that serum miR-101 downregulation was associated with shorter overall survival and recurrence free survival. Our present results implicated serum miR-101 might be a useful biomarker for the clinical diagnosis and prognosis of osteosarcoma.
This experiment studied the influence law of the strength of CPB affected by tailings content, Gobi aggregate content, cement content, and slurry concentration. The results show, for the CPB with ...concentration of 77%, when the addition amount of cement reaches 20%, the addition amounts of tailings and Gobi aggregate change within the ranges of 12∼24% and 56∼68%, respectively. The strength of CPB has been gradually improved when the addition amount of Gobi aggregates decreases and the addition amount of tailings increases. In this case, the slump of CPB changes within the range of 26.5 cm∼26.9 cm while the strength of CPB changes within the range of 4.021∼6.845 MPa. Considering future utilization value of tailings, the addition amount is finally set at 16% in production, and the addition amount of Gobi aggregate is set at 64%; namely, tailings: Gobi aggregate = 20 : 80. When the addition amount of cement is 20% (cement/(tailings + Gobi aggregates) = 1 : 4), the strength of CPB reaches 5.62 MPa which meets the production requirement. When the heading machine is used for tunnelling mine roadway in bottom backfill of VCR stope, no collapse or delamination occurs without support, showing good stability and integrity of backfill. When the adjacent stope ore is mined, the backfill with cement content of 11.1%, 14.3%, 20%, and 25% is exposed. In the process of mining, no collapse or delamination occurs. Therefore, the proportion of various backfill materials applied in production is reasonable, being verified by the experiment and field test.
•Large-deformation formulation of 3D A-FEM for multiple crack evolution in composites.•Nonlinear element augmentation procedure for element stiffness and residual.•Seamless coupling of intra- and ...inter-laminar cracks with geometric nonlinearity.•Demonstrated analysis capability for coupled damage evolution in composite.
This paper, for the first time in literature, formulated and validated a three-dimensional, nonlinear augmented finite element method (3D A-FEM) that can account for multiple crack evolution in laminated composites under large deformation. The 3D A-FEM accounts for all major cracking events (intra-ply matrix cracking, fiber rupture/kinking, and inter-ply delamination) with explicit cohesive cracks. The computational scheme is achieved by coupling the 3D A-FEs for intra-ply cracks with 3D cohesive interface elements for inter-ply delamination. The strong discontinuities of both intra- and inter-ply cracks are explicitly represented by the geometrically nonlinear cohesive zone models (CZMs). The numerical capability is demonstrated by several benchmark tests with both in-plane and out-of-plane loadings. Results show that the A-FEM predicted progressive damage processes, including the arbitrary initiation of multiple cracks and their nonlinearly coupled progression with delamination all the way up to the final catastrophic failure, are all in good agreement with experimental results.
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