Dahlrosario6427

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Many studies have examined changes in soil microbial community structure and composition by carbon nanomaterials (CNMs). Few, however, have investigated their impact on microbial community functions. This study explored how fullerene (C60) and multi-walled carbon nanotubes (M50) altered functionality of an agricultural soil microbial community (Archaea, Bacteria and Eukarya), using microcosm experiments combined with GeoChip microarray. M50 had a stronger effect than C60 on alpha diversity of microbial functional genes; both CNMs increased beta diversity, resulting in functional profiles distinct from the control. M50 exerted a broader, severer impact on microbially mediated nutrient cycles. Together, these two CNMs affected CO2 fixation pathways, microbial degradation of diverse carbohydrates, secondary plant metabolites, lipids and phospholipids, proteins, as well as methanogenesis and methane oxidation. They also suppressed nitrogen fixation, nitrification, dissimilatory nitrogen reduction, eukaryotic assimilatory nitrogen reduction, and anaerobic ammonium oxidation (anammox). Phosphorus and sulfur cycles were less vulnerable; only phytic acid hydrolysis and sulfite reduction were inhibited by M50 but not C60. Network analysis suggested decoupling of nutrient cycles by CNMs, manifesting closer and more hierarchical gene networks. This work reinforces profound impact of CNMs on soil microbial community functions and ecosystem services, laying a path for future investigation in this direction. Silver-based semiconductor photocatalysts are promising materials for solving environmental and energy issues due to their strong optical absorption, excellent quantum efficiency and photoelectrochemical properties. However, the uncontrollable photocorrosion and high use cost of single silver-based semiconductor photocatalysts limit its practical application. selleckchem The construction of Z-scheme photocatalytic systems that mimic natural photosynthesis can not only enhance the photocatalytic activity of silver-based semiconductor photocatalysts, but also improve their stability and reduce the use costs. This critical review concisely highlights the basic principles of Z-scheme photocatalytic systems, and discusses the construction of silver-based semiconductor Z-scheme photocatalytic systems and the roles of metallic Ag in there and summarizes the synthesis methods of silver-based semiconductor Z-scheme photocatalytic systems. Then, a series of the solar-driven applications are elaborated, including organic pollutants degradation, hydrogen production, and carbon dioxide reduction. Meanwhile, the mechanism and difficult level of these photocatalytic reactions are also described. Besides, metal organic frameworks (MOFs) as a novel type of photocatalysts have attracted growing attention. The novel combination of silver-based semiconductors with typical photoactive MOFs is highlighted based on the Z-scheme photocatalytic systems. Eventually, the future challenges and prospects in the development of silver-based semiconductor Z-scheme photocatalytic systems are presented. Electrolytic manganese residue (EMR) is a potentially harmful industrial solid waste that should be addressed. In the study, the red mud, carbide slag and blast furnace slag were used as stabilization/solidification (S/S) agents to S/S Mn2+, and simultaneous reused it as raw material to prepare road base material. The S/S behavior of manganese, unconfined compressive strength (UCS) of road base material with different Al/Si ratios, leaching test and the S/S mechanisms were investigated. The results showed that the Mn2+ can be well solidified when the S/S agents reach up to 20 %. The 7-day UCS of the road base material was 6.1 MPa with the Al/Si ratio of 0.48, which meets the highway standards. When Al/Si = 0.48, the formation amount of CaAl2Si2O8·4H2O and ettringite increased, which promoted the adsorption and wrap of Mn2+. The content of active AlⅣ and AlⅥ increased after S/S. Mn2SiO4 and Ca4Mn4Si8O24 were produced by the charge balance effect, and the new chemical bond was formed. Meanwhile, the Mn2+ is oxidized to more stable MnO2 to achieve the S/S of Mn2+. This research provides an effective way to solidify Mn2+ and solves the problem of large-scale utilization of EMR and other solid waste. Arsenic (As), a chronic poison and non-threshold carcinogen, is a food chain contaminant in rice, posing yield losses as well as serious health risks. Selenium (Se), a trace element, is a known antagonist of As toxicity. In present study, RNA seq. and proteome profiling, along with morphological analyses were performed to explore molecular cross-talk involved in Se mediated As stress amelioration. The repair of As induced structural deformities involving disintegration of cell wall and membranes were observed upon Se supplementation. The expression of As transporter genes viz., NIP1;1, NIP2;1, ABCG5, NRAMP1, NRAMP5, TIP2;2 as well as sulfate transporters, SULTR3;1 and SULTR3;6, were higher in As + Se compared to As alone exposure, which resulted in reduced As accumulation and toxicity. The higher expression of regulatory elements like AUX/IAA, WRKY and MYB TFs during As + Se exposure was also observed. The up-regulation of GST, PRX and GRX during As + Se exposure confirmed the amelioration of As induced oxidative stress. The abundance of proteins involved in photosynthesis, energy metabolism, transport, signaling and ROS homeostasis were found higher in As + Se than in As alone exposure. Overall, present study identified Se responsive pathways, genes and proteins involved to cope-up with As toxicity in rice. In this paper, the binding characteristics of aflatoxin B1 (AFB1) with the herring sperm deoxyribonucleic acid (DNA) in vitro were investigated through different analytical methods. The ultraviolet-visible spectroscopy (UV-vis), fluorescence, and circular dichroism (CD) spectra results showed that a new AFB1-DNA complex was formed. All the results suggested that AFB1 interacted with free DNA in vitro in an intercalating binding mode. The results of the DNA melting experiments also showed that the melting temperature of DNA increased by about 12.1 °C due to the addition of AFB1, which was supposed to be closely related to the intercalation of AFB1 into DNA. The agar gel electrophoresis experiments further confirmed that the binding mode of AFB1 and free DNA in vitro was indeed intercalation. In addition, the fluorescence quenching induced by adding AFB1 to the ethidium bromide-DNA (EB-DNA) mixture indicated the presence of competitive non-covalent intercalating binding interaction with a competitive binding constant of 5.