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Neonicotinoids have recently been banned in the European Union due to concerns about their environmental safety. Thiacloprid is a neonicotinoid, and is frequently used in agricultural pest control. However, the lack of quantitative methods for assessing its multiple metabolites has made it difficult to perform a comprehensive safety assessment. Therefore, we established an analytical method for effectively determining thiacloprid and its five metabolites in vegetables and flowers using QuEChERS-HPLC-MS/MS. The samples were extracted with acidified acetonitrile (containing 0.5% acetic acid) and were cleaned with graphitised carbon black (GCB) and octadecylsilane (C18) before the residue analysis. This method provided linearity ranging from 2–2000 μg kg−1, and its linear regression coefficients exceeded 0.995. Limits of Quantitation (LOQs) are achieved at 2 μg kg−1， and Limits of Detection (LODs) ranged from 0.09–0.80 μg kg−1. The method was validated on seven matrices spiked at 2, 200, and 2000 μg kg−1. Average recoveries ranged from 77–119%, with an intra-day Relative Standard Deviation (RSDr) of 1.5–13.4% and an inter-day Relative Standard Deviation (RSDR) of 0.9–14.4%. This method was used on cucumbers sprayed with thiacloprid and 19 types of flower samples collected from the field, after which thiacloprid and several of its metabolites were detected.

Apurinic/apyrimidinic (AP) sites are one of the most abundant DNA lesions and are mainly repaired by AP endonucleases (APEs). While most eukaryotic genomes encode two APEs, plants usually possess three APEs, namely APE1L, APE2, and ARP. To date, the biological relevance and functional divergence of plant APEs are unclear. Here, we show that the three plant APEs have ancient origins, with the APE1L clade being plant-specific. In Arabidopsis thaliana, simultaneously mutating APE1L and APE2, but not ARP alone or in combination with either APE1L or APE2, results in clear developmental defects linked to genotoxic stress. Genetic analyses indicated that the three plant APEs have different substrate preferences in vivo. ARP is mainly responsible for AP site repair, while APE1L and APE2 prefer to repair 3′-blocked single-stranded DNA breaks. We further determined that APEs play an important role in DNA repair and the maintenance of genomic integrity in meiotic cells. The ape1l ape2 double mutant exhibited a greatly enhanced frequency of sporulation 1 (SPO11-1)-dependent and SPO11-1-independent double-stranded DNA breaks. The DNA damage response (DDR) was activated in ape1l ape2 to trigger pollen abortion. Our findings suggest functional divergence of plant APEs and reveal important roles of plant APEs during vegetative and reproductive development.

As an important part of cultural heritage, paper cultural relics have important historical, scientific and humanistic values. However, a large number of paper cultural relics are suffering from aging, mildew, yellowing, cracks, embrittlement and other threats, or are even completely damaged. To enhance the strength of paper cultural relics and prolong the life of paper cultural relics, a novel CMC-acrylate-OVPOSS graft copolymer was synthesized with carboxymethyl cellulose (CMC), methyl methacrylate (MMA), butyl acrylate (BA), hydroxyethyl methacrylate (HEMA), glycidyl methacrylate (GMA), octavinyl polyhedral oligomeric silsesquioxane (OVPOSS). The synthesized materials were analyzed by infrared spectroscopy, X-ray diffractometer, thermal analyzer and X-ray photoelectron spectroscopy. In addition, the reinforcement solution was coated on the surface of the paper, and the protective effect of the reinforcement solution on the paper was evaluated by testing the mechanical and optical properties of the paper. When the reinforcement solution with a mass concentration of 10 % was coated on the paper, the mechanical properties of the paper were greatly improved, and the gloss and whiteness were basically unchanged.

Hydrogen energy has long been recognized as a clean alternative to conventional fossil fuels, which can be applied in a wide range of transportation and power generation applications. The rational design and engineering of high-performance and robust catalysts for hydrogen evolution reaction (HER) shows not a great significance but a challenge for efficient electrochemical water splitting. Herein, a new type of Ni-based Ni-ABDC precursor has been obtained, which leads to the formation of N-doped porous carbon nanomaterials uniformly coated with well-proportioned bimetallic AgNi alloys via a stepwise strategy. To their credit, all samples of AgNi/NC-X are structurally calcined from the pristine AgNi-ABDC-X by tuning the different concentration of AgNO3, which means all of them maintain the vermicelli-like morphology compared with Ni-ABDC. The series of AgNi/NC-X materials can be regarded as effective electrocatalysts for HER both in acidic and alkaline media, but an acid-leaching phenomenon is observed. Among them, the as-prepared AgNi/NC-2 exhibits a low overpotential of 103 mV at the current density of 10 mA cm−2 and decent durability with a high retention rate of 90.9% after 10 h in 1.0 M KOH electrolyte. The compelling HER properties of AgNi/NC-2 can be attributed to the synergistic effect between the hierarchical carbon materials, partial N-doping and abundant AgNi alloys. Meanwhile, this study provides a practicable method for the development of efficient HER electrocatalysts for energy applications, which can be conveniently prepared through the reasonable introduction of active components in the crystalline inorganic-organic precursors.

0D SnSe quantum dots are uniformly distributed on 2D MXene nanosheets to enhance the cycling stability of sodium-ion batteries.

La2IrO6/IrO2 nanotubes with superior catalytic performance for acid oxygen evolution were prepared via an electrospinning approach. In situ Raman spectra and DFT calculations confirmed the synergistic cooperation between the two types of Ir active sites in La2IrO6/IrO2.

Metal–organic frameworks (MOFs) have become popular precursors for the construction of porous carbon nanomaterials (CNMs) with inherited characteristics and advantages, showing great potential in environment and energy applications.

Contains fulltext : 290804.pdf (Publisher’s version ) (Closed access) Attention-deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder with a major genetic component. Here, we present a genome-wide association study meta-analysis of ADHD comprising 38,691 individuals with ADHD and 186,843 controls. We identified 27 genome-wide significant loci, highlighting 76 potential risk genes enriched among genes expressed particularly in early brain development. Overall, ADHD genetic risk was associated with several brain-specific neuronal subtypes and midbrain dopaminergic neurons. In exome-sequencing data from 17,896 individuals, we identified an increased load of rare protein-truncating variants in ADHD for a set of risk genes enriched with probable causal common variants, potentially implicating SORCS3 in ADHD by both common and rare variants. Bivariate Gaussian mixture modeling estimated that 84-98% of ADHD-influencing variants are shared with other psychiatric disorders. In addition, common-variant ADHD risk was associated with impaired complex cognition such as verbal reasoning and a range of executive functions, including attention. 01 februari 2023

We conduct numerical simulations and develop a macrotransport theory to show a diffusiophoresis-based, order-of-magnitude enhancement in the thickness of the colloidal layer produced by unidirectional drying of an electrolyte-colloid suspension.

People with diabetes mellitus (DM) have increased risk of depressive symptoms (DS) or anxious symptoms (AS). This study explores whether awareness of DM will contribute to prevalence of DS or AS.The baseline data including 81,717 adults from Southwest China was analyzed. DS and AS were assessed using PHQ-2 and GAD-2. Exposures were defined as 1) having self-reported physician diagnosis of diabetes (self-reported DM), 2) no prior diagnosis of diabetes but meeting diagnostic criteria (newly diagnosed DM), 3) having self-reported physician diagnosis or meeting criteria of non-diabetic diseases (non-diabetic patients), 4) healthy participants. Generalized linear mixed models were used to assess impact of presence and awareness of DM on DS or AS, adjusting for regional and individual related factors.The prevalence of DS in self-reported DM, newly diagnosed DM, non-diabetic patient and healthy participants was 7.08 %, 4.30 %, 5.37 % and 3.17 %. The prevalence of AS was 7.80 %, 5.77 %, 6.37 % and 3.91 %. After adjusting for related factors, compared with healthy participants, self-reported DM and non-diabetic patients were associated with DS [AORDS and AS were assessed through self-report and may suffer recall or information bias.The association between awareness of diabetes and DS/AS suggests to pay attention to distinguish between self-reported and newly diagnosed DM and screening for DS and AS in diabetic population.

Acquiring metal-free horizontal single-walled carbon nanotube (SWNT) arrays is of paramount importance for the development of stable nanodevices. However, the majority of SWNTs are prepared with transition metal-based catalysts, which will inevitably leave metallic residuals and deteriorate the device performance. Here, green and low-cost NaCl is developed as a metal-free catalyst. By employing a strategy of rapid nucleation at a higher temperature followed by steady growth at a lower temperature, the production of a well-defined NaCl catalyst capable of growing metal-free horizontal SWNT arrays with an average density of ∼100 tubes per 100 μm is realized. Besides, we prove that the as-grown metal-free SWNT arrays have a unique advantage in preparing stable devices for eliminating the potential risk of local mass catalyst residuals. Hence, the current study can offer a feasible solution to promote practical applications of SWNT-based next-generation nanodevices.