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Metronidazole(MNZ), prone to accumulate in the environment, is a nitroimidazole antibiotic and its metabolites have potential carcinogenicity and mutagenicity. In this paper, the degradation characteristics of MNZ by coupled ferrate/peroxyacetic acid〔Fe(Ⅵ)/PAA〕technology, as well as the simulation of MNZ degradation and reaction mechanism, were investigated. When the dosages of Fe(Ⅵ) as 500 μmol/L and PAA as 100 μmol/L, the degradation of MNZ reached 94.85% at pH of 8 in 60 min, and the degradation process followed pseudo-first-order kinetics. Variable experiments showed that the degradation of MNZ was positively correlated with the dosage of Fe(Ⅵ) and PAA, and the best effect was achieved at pH=8. Chloride (Cl-) and nitrate (NO3-) in the water matrix had little effect on the degradation of MNZ. Ammonium salt (NH4+) could promote the degradation of MNZ,while bicarbonate (HCO3-) and humic acid (HA) inhibited the degradation. The removal of MNZ in simulated medical wastewater by Fe(Ⅳ)/PAA was similar to that in ultra-pure water, which could achieve better removal effect. Probe experiments and quenching experiments showed that PAA accelerated the removal of MNZ from active species. H2O2 coexisting with PAA was the main activator of Fe(Ⅵ) while the main active species of Fe(Ⅵ)/PAA system were Fe(V) and Fe(Ⅳ). The results were expected to provide theoretical reference and data support for the application of Fe(Ⅵ)/PAA system in the deep treatment of MNZ in medical wastewater.

The continuously increasing bank sizes have received much attention from both policymakers and researchers. We present new estimates of returns to scale in cost, revenue, and profit for European banks over 2000–2020 based on nonparametric, local‐linear methods. We find that most banks faced increasing returns to scale in cost and decreasing returns to scale in revenue and profit across years, across European countries, and across bank size quartiles. Our results suggest that restricting the size of banks may not bring too much loss of revenue and profit, but could prevent European banks from exploiting increasing returns to scale in cost. [ABSTRACT FROM AUTHOR]

Summary: Hexaploid wheat (Triticum aestivum), a major staple crop, has a remarkably large genome of ~14.4 Gb (containing 106 913 high‐confidence [HC] and 159 840 low‐confidence [LC] genes in the Chinese Spring v2.1 reference genome), which poses a major challenge for functional genomics studies. To overcome this hurdle, we performed whole‐exome sequencing to generate a nearly saturated wheat mutant database containing 18 025 209 mutations induced by ethyl methanesulfonate (EMS), carbon (C)‐ion beams, or γ‐ray mutagenesis. This database contains an average of 47.1 mutations per kb in each gene‐coding sequence: the potential functional mutations were predicted to cover 96.7% of HC genes and 70.5% of LC genes. Comparative analysis of mutations induced by EMS, γ‐rays, or C‐ion beam irradiation revealed that γ‐ray and C‐ion beam mutagenesis induced a more diverse array of variations than EMS, including large‐fragment deletions, small insertions/deletions, and various non‐synonymous single nucleotide polymorphisms. As a test case, we combined mutation analysis with phenotypic screening and rapidly mapped the candidate gene responsible for the phenotype of a yellow‐green leaf mutant to a 2.8‐Mb chromosomal region. Furthermore, a proof‐of‐concept reverse genetics study revealed that mutations in gibberellic acid biosynthesis and signalling genes could be associated with negative impacts on plant height. Finally, we built a publically available database of these mutations with the corresponding germplasm (seed stock) repository to facilitate advanced functional genomics studies in wheat for the broad plant research community. [ABSTRACT FROM AUTHOR]

Key message: A minor-effect QTL, Qhd.2AS, that affects heading date in wheat was mapped to a genomic interval of 1.70-Mb on 2AS, and gene analysis indicated thatthe C2H2-type zinc finger proteingene TraesCS2A02G181200is the best candidate for Qhd.2AS. Heading date (HD) is a complex quantitative trait that determines the regional adaptability of cereal crops, and identifying the underlying genetic elements with minor effects on HD is important for improving wheat production in diverse environments. In this study, a minor QTL for HD that we named Qhd.2AS was detected on the short arm of chromosome 2A by Bulked Segregant Analysis and validated in a recombinant inbred population. Using a segregating population of 4894 individuals, Qhd.2AS was further delimited to an interval of 0.41 cM, corresponding to a genomic region spanning 1.70 Mb (from 138.87 to 140.57 Mb) that contains 16 high-confidence genes based on IWGSC RefSeq v1.0. Analyses of sequence variations and gene transcription indicated that TraesCS2A02G181200, which encodes a C2H2-type zinc finger protein, is the best candidate gene for Qhd.2AS that influences HD. Screening a TILLING mutant library identified two mutants with premature stop codons in TraesCS2A02G181200, both of which exhibited a delay in HD of 2–4 days. Additionally, variations in its putative regulatory sites were widely present in natural accession, and we also identified the allele which was positively selected during wheat breeding. Epistatic analyses indicated that Qhd.2AS-mediated HD variation is independent of VRN-B1 and environmental factors. Phenotypic investigation of homozygous recombinant inbred lines (RILs) and F2:3 families showed that Qhd.2AS has no negative effect on yield-related traits. These results provide important cues for refining HD and therefore improving yield in wheat breeding programs and will deepen our understanding of the genetic regulation of HD in cereal plants. [ABSTRACT FROM AUTHOR]

Si-based optical position-sensitive detectors (PSDs) have stimulated the interest of researchers due to their wide range of practical applications. However, due to the rigidity and fragility of Si crystals, the applications of flexible PSDs have been limited. Therefore, we presented a flexible broadband PSD based on a WS2/Si heterostructure for the first time. A scalable sputtering method was used to deposit WS2 thin films onto the etched ultrathin crystalline Si surface. The fabricated flexible PSD device has a broad spectral response in the wavelength range of 450–1350 nm, with a high position sensitivity of ∼539.8 mV·mm−1 and a fast response of 2.3 µs, thanks to the strong light absorption, the built-in electrical field at the WS2/Si interface, and facilitated transport. Furthermore, mechanical-bending tests revealed that after 200 mechanical-bending cycles, the WS2/Si PSDs have excellent mechanical flexibility, stability, and durability, demonstrating the great potential in wearable PSDs with competitive performance. [ABSTRACT FROM AUTHOR]