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The lack of genome editing platforms has hampered efforts to study and improve forage crops that can be grown on lands not suited to other crops. Here, we established efficient Agrobacterium‐mediated clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR‐associated nuclease 9 (Cas9) genome editing in a perennial, stress‐tolerant forage grass, sheepgrass (Leymus chinensis). By screening for active single‐guide RNAs (sgRNAs), accessions that regenerate well, suitable Agrobacterium strains, and optimal culture media, and co‐expressing the morphogenic factor TaWOX5, we achieved 11% transformation and 5.83% editing efficiency in sheepgrass. Knocking out Teosinte Branched1 (TB1) significantly increased tiller number and biomass. This study opens avenues for studying gene function and breeding in sheepgrass. [ABSTRACT FROM AUTHOR]

A copper ion imprinted chitosan flocculant (Cu2+@CTS) was synthesized by the molecular imprinting technique to improve the flocculation selectivity of chitosan to heavy metal ions. The effects of the amount of crosslinking agent, crosslinking time, temperature on the properties of the material were systematically investigated. Under the optimum preparation conditions, the flocculation rate and removal rate of Cu2+@CTS were 98.26% and 88.4%, respectively, 2.85 and 3.86 times higher than that of the unprinted chitosan flocculant. On this basis, the flocculation selectivity of Cu2+@CTS to Cu2+ in the presence of Zn2+, Ni2+ and other competitive ions was further explored. The experimental results indicated the removal rate of Cu2+ by Cu2+@CTS was as high as 70%–85%, which was 2.2–2.7 times that of other ions, while the removal rate of three metal ions by non‐imprinted chitosan flocculants was less than 35%. This study provided a reference for improving the selectivity of chitosan‐based flocculant to Cu2+. [ABSTRACT FROM AUTHOR]

BACKGROUND: Plant secondary metabolites and their modified derivatives play an important role in the discovery and development of novel insecticides. The natural plant product (3E)‐4,8‐dimethyl‐1,3,7‐nontriene (DMNT) has been proven to be able to effectively repel and kill the lepidopteran insect pest Plutella xylostella. RESULTS: In this study, four oxygenated derivatives of DMNT were synthesized by allylic hydroxylation and subsequent etherification or esterification. Bioassays on P. xylostella larvae showed that the compounds DMNT‐OCH3 (2), DMNT‐OCy (3) and DMNT‐OAc (4) were more toxic to the larvae than DMNT alone. The most pronounced effect was observed for compound 2, which showed a 22.23% increase in lethality at a concentration of 0.25 μm. Moreover, the peritrophic matrix (PM) barrier in the insect midgut was more severely damaged by compounds 2, 3 and 4 than by DMNT. The median lethal concentration (LC50, 48 h) of compounds 2, 3 and 4 on P. xylostella was determined to be 0.98, 1.13 and 1.11 mg mL−1, respectively, which is much lower than the commercial insecticides eucalyptol (2.89 mg mL−1) and thymol (2.45 mg mL−1). CONCLUSION: These results suggested that oxygenated DMNT derivatives offer a significantly improved killing effect over DMNT on P. xylostella. This work has provided a basis for further design, structural modification and development of DMNT as botanical insecticides. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The lepidopteran crop pest Plutella xylostella causes severe constraints on Brassica cultivation. Here, we report a novel role for RPX1 (resistance to P. xylostella) in resistance to this pest in Arabidopsis thaliana. The rpx1‐1 mutant repels P. xylostella larvae, and feeding on the rpx1‐1 mutant severely damages the peritrophic matrix structure in the midgut of the larvae, thereby negatively affecting larval growth and pupation. This resistance results from the accumulation of defence compounds, including the homoterpene (3E)−4,8‐dimethyl‐1,3,7‐nonatriene (DMNT), due to the upregulation of PENTACYCLIC TRITERPENE SYNTHASE 1 (PEN1), which encodes a key DMNT biosynthetic enzyme. P. xylostella infestation and wounding induce RPX1 protein degradation, which may confer a rapid response to insect infestation. RPX1 inactivation and PEN1 overexpression are not associated with negative trade‐offs for plant growth but have much higher seed production than the wild‐type in the presence of P. xylostella infestation. This study offers a new strategy for plant molecular breeding against P. xylostella. Summary statement: Plutella xylostella pests show severely negative influence on plant growth and reproduction, and the identification of resistant genes is essential. This study reveals that inactivation of RPX1 confers significant resistance to the pest by enhancing PEN1 expression and accumulating the homoterpene DMNT in Arabidopsis thaliana. [ABSTRACT FROM AUTHOR]

This work derives an incompressible variational multiscales time‐averaged Navier–Stokes (NS) formulation that aims at obtaining accurate steady state solutions. Rather than using the standard time instantaneous velocity and pressure, the new formulation devises a time averaging procedure based on rewriting and solving the NS equations in terms of the newly defined time‐averaged velocity and pressure. Hence, the method could be understood as a convenient change of variable so that the problem is rewritten directly in terms of the steady state quantities. The important advantage of such a point of view is that it can in principle be applied to any other formulation. Such time averaging procedure is complemented by two time step modification strategies in order to accelerate the convergence to the steady state. The guidelines of an integrated framework are presented in the article, starting with the description of the proposed numerical technique applied to general incompressible flows. The explanation is enhanced with a one‐dimensional (1D) nonlinear oscillator example. Several results are presented concerning analytical benchmarks, simulation of flows in laminar, transitional and turbulent regimes with and without an inherently steady solution. [ABSTRACT FROM AUTHOR]

The prevalence of cardiovascular disease (CVD) is higher in patients with schizophrenia than in the general population. We aimed to investigate whether atypical antipsychotics (AAP) increase the levels of lipoprotein‐associated phospholipase A2 (Lp‐PLA2), thereby increasing the risk of CVD. The data were from inpatients aged 18–60 years with a diagnosis of schizophrenia according to ICD‐10 at the Affiliated Brain Hospital of Nanjing Medical University who underwent physical examination between 1 October 2014 and 30 September 2016. A retrospective cohort study was used to analyse the correlation between AAP, Lp‐PLA2 levels and the CVD risk (it was determined that Lp‐PLA2 values >200 ng/mL were defined as high CVD risk) in patients treated with monotherapy, olanzapine, clozapine or quetiapine. Data were collected for 452 patients with eligible schizophrenia: 163 treated with clozapine, 186 treated with olanzapine, 47 treated with quetiapine and 56 receiving no medication. Compared with the no‐medication patients, AAP administration in patients with olanzapine, clozapine or quetiapine had higher serum Lp‐PLA2 levels when age, sex, BMI and fasting glucose level were matched. AAP were significantly associated with serum Lp‐PLA2 level by Spearman's correlation coefficients. The results of logistic regression analysis showed that AAP administration was an independent factor of CVD risk when adjusted by potential confounding factors. This study is the first to confirm that AAP administration, especially clozapine and olanzapine, could increase Lp‐PLA2 levels and CVD risk, independent of drug‐induced weight gain in schizophrenia. The extent and the factors of increasing Lp‐PLA2 level and CVD risk in olanzapine, clozapine and quetiapine are discrepant. The possible effects of AAP on Lp‐PLA2 in schizophrenia patients are involved in pro‐inflammatory cytokines and hormones. [ABSTRACT FROM AUTHOR]

Background Papular acantholytic dyskeratosis ( PAD) of the anogenital/genitocrural area is described as a rare distinct clinicopathological entity known to dermatopathologists, although its characteristic histopathologic pattern resembles both Hailey-Hailey disease and Darier disease. The objective of this study is to describe the clinical characteristics, histopathologic features and response to treatment of PAD. Methods We report in detail six cases of PAD. A literature search of the keyword 'papular acantholytic dyskeratosis' was performed on Google scholar and PubMed, 21 cases of this entity were found. A total of 27 patients including our six cases are reviewed in this study. Results The mean age at diagnosis was 38.8 years with a male to female ratio of 0.8 : 1. Clinically, papular lesions (55.6%) are the typical manifestation of PAD, and the anogenital area (63%) is the most commonly involved site. Lesions were resistant to topical steroids, subcutaneous interferon and antibiotics while one case showed complete resolution of the lesions after retinoid therapy. Laser therapy showed good results in one case. None of the patients had spontaneous remission. Conclusion Awareness of the clinicopathological hallmarks herein may be important to avoid underdiagnosis of PAD and may contribute to understanding the pathogenesis of this rare disease. [ABSTRACT FROM AUTHOR]