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The GaSiAlOxcomposite oxide and the VOx/GaSiAlOxseries catalysts have been prepared through the hydrothermal synthesis method. Meanwhile, the physicochemical properties of the catalysts were characterized by means of XRD, SEM, TEM, XPS and FT-IR, and tested in the hydroxylation reaction of phenol. The morphology of the synthesized gallium-doped GaSiAlOxcomposite oxide was 3D cross-linked and coral-like from the SEM characterization. Meanwhile, the XPS characterization results indicate that when Ga was added, the valence state of the active center of the catalyst could be precisely regulated. Based on the precise regulation of the vanadium valence state by Ga₂O₃, the VOx/GaSiAlOxcatalysts exhibited highly efficient catalytic activity. Under the optimal reaction conditions, the conversion rate of phenol was 71.4% and the selectivity for dihydroxybenzene was 92.3%.

Isoprene is a typical biomarker in human exhaled breath and can be used to diagnose chronic liver disease (CLD). However, its stable alkene structure hinders easy detection on metal–oxide–semiconductor (MOS) sensor because of the low sensitivity. Herein, we reported a surface modification strategy to boost the isoprene sensitivity of ZnCo2O4. To expound it, ZnCo2O4 hierarchal nanospheres (HNSs) were prepared by a solvothermal route and then decorated with Ag nanoparticles via a photoreduction method. Benefiting from the outstanding spillover effect of Ag as well as the increased oxygen vacancy, the obtained Ag/ZCo2O4 HNSs showed superior isoprene-sensing performance to the bare ZnCo2O4 HNSs, especially of higher sensitivity (5.9 versus 1.3 for 1000-ppb isoprene at 260 °C) and better selectivity (Sisoprene/ammonia: 3.3 versus 1.2). Besides, the Ag/ZnCo2O4 sensor also showed the low limit of detection (LOD) (5 ppb) and good stability. These features make the Ag/ZnCo2O4 sensor a promising candidate for human breath analysis. The results of first principal calculations reveal that the improved isoprene sensitivity and selectivity of Ag/ZnCo2O4 HNSs can be attributed to the enhanced isoprene absorption on ZnCo2O4 HNSs after Ag decoration.

Graphical Abstract:

Higher power, higher efficiency, and better stability are very urgent for the sub-millimeter wave and terahertz traveling-wave tube (TWT). A novel serpentine waveguide circuit structure with changeable narrow side and nonconcentric circular bends [novel serpentine waveguide circuit topology (NSWC)] is proposed to meet above demands in this article. Based on the simulation analysis results of electromagnetic analysis software High Frequency Structure Simulator(HFSS), the NSWC owns higher on-axis coupling impedance, which is crucial for high power and efficiency, and wider stopband gap near the ${2}\pi $ eigenmode that means improved stability than other three commonly used structures: traditional serpentine waveguide slow wave structure (TS-SWS), hybrid-serpentine slow wave structures (HS-SWSs), and folded waveguide slow wave structure with modified circular bends (MCB-SWS). In order to validate this novel topology, Microwave-Tube Simulator Suite (MTSS) software package and Computer Simulation Technology Particle Studio (CST-PS) are applied to design and analyze two types of ${E}$ -band TWTs: TWT-I with MCB-SWS and TWT-II with the NSWC. The simulated results show that the stable output powers and electronic efficiencies for TWT-II are more than 148.48 W and 10.01% in the frequency range of 81–86 GHz, respectively, which are more than 32.7% and 28.3% higher than those for TWT-I in the same frequency range, which confirm that the NSWC is a promising slow wave circuit with raised output power, increased electronic efficiency and improved stability in millimeter wave and terahertz frequency bands.

ABSTRACTIn this study, we are interested primarily in how a structural factor – social capital – relates to Chinese national government agencies’ partner selection in environmental protection. Our study finds that their partner selection is associated positively with activity closure and popularity closure while being negatively influenced by cyclicity closure. Moreover, their partner selection is characterized predominantly by a leading-agency coordinated collaboration model, which favors the engagement of a shared third agency and emphasizes the similarity of interests. This study expands the theoretical connotations of social capital and provides new insights into the mechanisms underlying actors’ partner selection in interagency collaboration.

Stereochemistry has an essential role in organic synthesis, biological catalysis and physical processes. In situ chirality identification and asymmetric synthesis are non-trivial tasks, especially for single-molecule systems. However, going beyond the chiral characterization of a large number of molecules (which inevitably leads to ensemble averaging) is crucial for elucidating the different properties induced by the chiral nature of the molecules. Here we report direct monitoring of chirality variations during a Michael addition followed by proton transfer and keto–enol tautomerism in a single molecule. Taking advantage of the chirality-induced spin selectivity effect, continuous current measurements through a single-molecule junction revealed in situ chirality variations during the reaction. Chirality identification at a high sensitivity level provides a promising tool for the study of symmetry-breaking reactions and sheds light on the origin of the chirality-induced spin selectivity effect itself.

ABSTRACT Tourmaline modified bitumen was prepared by blending base bitumen with tourmaline powder. Effect of temperature, frequency as well as the content of tourmaline powder on the complex modulus and [...]

ABSTRACT The flame-retarding effects, synergistic effect, and combustion properties of asphalt binder modified with organo montmorillonite (OMMT) and alumina trihydrate (ATH) were investigated on the basis of the limiting oxygen [...]

Data augmentation is a critical technique in object detection, especially the augmentations targeting at scale invariance training (scale-aware augmentation). However, there has been little systematic investigation of how to design scale-aware data augmentation for object detection. We propose Scale-aware AutoAug to learn data augmentation policies for object detection. We define a new scale-aware search space, where both image- and instance-level augmentations are designed for maintaining scale robust feature learning. Upon this search space, we propose a new search metric, termed Pareto Scale Balance, to facilitate efficient augmentation policy search. In experiments, Scale-aware AutoAug yields significant and consistent improvement on various object detectors (e.g., RetinaNet, Faster R-CNN, Mask R-CNN, and FCOS), even compared with strong multi-scale training baselines. Our searched augmentation policies are generalized well to other datasets and instance-level tasks beyond object detection, e.g., instance segmentation. The search cost is much less than previous automated augmentation approaches for object detection, i.e., 8 GPUs across 2.5 days versus. 800 TPU-days. In addition, meaningful patterns can be summarized from our searched policies, which intuitively provide valuable knowledge for hand-crafted data augmentation design. Based on the searched scale-aware augmentation policies, we further introduce a dynamic training paradigm to adaptively determine specific augmentation policy usage during training. The dynamic paradigm consists of an heuristic manner for image-level augmentations and a differentiable copy-paste-based method for instance-level augmentations. The dynamic paradigm achieves further performance improvements to Scale-aware AutoAug without any additional burden on the long tailed LVIS benchmarks. We also demonstrate its ability to prevent over-fitting for large models, e.g., the Swin Transformer large model. Code and models are available at https://github.com/dvlab-research/SA-AutoAug.

In this paper, we present a conceptually simple, strong, and efficient framework for fully- and weakly-supervised panoptic segmentation, called Panoptic FCN. Our approach aims to represent and predict foreground things and background stuff in a unified fully convolutional pipeline, which can be optimized with point-based fully or weak supervision. In particular, Panoptic FCN encodes each object instance or stuff category with the proposed kernel generator and produces the prediction by convolving the high-resolution feature directly. With this approach, instance-aware and semantically consistent properties for things and stuff can be respectively satisfied in a simple generate-kernel-then-segment workflow. Without extra boxes for localization or instance separation, the proposed approach outperforms the previous box-based and -free models with high efficiency. Furthermore, we propose a new form of point-based annotation for weakly-supervised panoptic segmentation. It only needs several random points for both things and stuff, which dramatically reduces the annotation cost of human. The proposed Panoptic FCN is also proved to have much superior performance in this weakly-supervised setting, which achieves 82% of the fully-supervised performance with only 20 randomly annotated points per instance. Extensive experiments demonstrate the effectiveness and efficiency of Panoptic FCN on COCO, VOC 2012, Cityscapes, and Mapillary Vistas datasets. And it sets up a new leading benchmark for both fully- and weakly-supervised panoptic segmentation.

Exploring novel and cost-effective anode materials is highly desired for the development of sodium-ion batteries (SIBs). Herein, an amorphous FePO4/reduced graphene oxide (FP-G) composite is prepared by a simple chemical precipitation method with leaching liquor of jarosite residue as Fe source. When used as a novel anode material for SIBs, this FP-G composite exhibits a high sodium storage activity (341.6 mAh g−1after 100 cycles at 0.2 A g−1), superior long-term cycling stability (215.8 mAh g−1after 1500 cycles at 0.5 A g−1), and outstanding high-rate capability (190.8 mAh g−1at 5.0 A g−1). The FP-G composite shows a significant pseudocapacitance behavior and good electrochemical reversibility during discharge and charge processes. This work proposes a simple, feasible, and cost-effective strategy for the high-valued utilization of jarosite residue, and deeply investigates the sodium storage mechanism and potential value of FP-G composite as a novel anode material for SIBs.

This study aimed to extract exosomes from the serum of rats with spinal cord injury and explore their potential as indicators for assessing the severity of spinal cord injury. Control rats were compared with rats in the mild and severe injury groups. Exosomes were isolated from rat serum using an optimized threshold condition with an ultra-high-speed flow cell sorter. Nanoparticle tracking analysis (NTA) was performed to determine the size distribution of exosomes, transmission electron microscopy (TEM) was used to observe the morphology of exosomes, and Western blot analysis was conducted to assess the expression of CD63(cluster of differentiation antigen 63) and CD9(cluster of differentiation antigen 9) proteins on the surface of exosomes. NanoFlow cytometry was utilized to evaluate the expression of CD63 and CD9. The optimal threshold condition for flow cytometry of exosomes was determined to be 0.002. Exosomes exhibited a cup-shaped morphology with a clean background. The percentages of exosomes in the control, mild injury, and severe injury groups were determined to be 6.4 × 1011particles/mL, 6.2 × 1011particles/mL, and 2.3 × 1011particles/mL, respectively. The mean sizes of exosomes were 129.25 nm ± 18.3, 117.93 nm ± 39.9, and 116.38 nm ± 36.5, respectively. The percentages of CD9 were 15.5% ± 0.037, 10.4% ± 0.082, and 7.4% ± 0.051, while the percentages of CD63 were 1.2% ± 0.025, 2.6% ± 0.067, and 1.5% ± 0.038 for the control, mild injury, and severe injury groups, respectively. Comparison analysis revealed that the diameter of exosomes in rat serum ranged from 80 nm to 150 nm. The percentage of exosomes decreased, and CD9 expression significantly decreased as the severity of spinal cord injury increased. Flow cytometry allows for the isolation of exosomes from serum with high purity and uniform particle size. The percentage of serum exosomes and the expression of CD9 may serve as potential diagnostic indicators for spinal cord injury models.

Although widely applied in treating hematopoietic malignancies, transplantation of hematopoietic stem/progenitor cells (HSPCs) is impeded by HSPC shortage. Whether circulating HSPCs (cHSPCs) in steady-state blood could be used as an alternative source remains largely elusive. Here we develop a three-dimensional culture system (3DCS) including arginine, glycine, aspartate, and a series of factors. Fourteen-day culture of peripheral blood mononuclear cells (PBMNCs) in 3DCS led to 125- and 70-fold increase of the frequency and number of CD34+cells. Further, 3DCS-expanded cHSPCs exhibited the similar reconstitution rate compared to CD34+HSPCs in bone marrow. Mechanistically, 3DCS fabricated an immunomodulatory niche, secreting cytokines as TNF to support cHSPC survival and proliferation. Finally, 3DCS could also promote the expansion of cHSPCs in patients who failed in HSPC mobilization. Our 3DCS successfully expands rare cHSPCs, providing an alternative source for the HSPC therapy, particularly for the patients/donors who have failed in HSPC mobilization.

Herein, a diatomite biomorphic Si-O doped carbon-based catalyst (DB-SiOC) was prepared using natural mineral diatomite as the silicon source and porous template. The results showed that the metal-free DB-SiOC catalyst exhibited ultrafast oxidation towards chlorophenol (CP) viaperoxymonosulfate (PMS) activation, which was almost one order of magnitudes than most of carbon-based catalysts. The DB-SiOC/PMS system also showed the high ability to resist the interference of environmental matrix. The radicals (•OH and SO4•‒) exhibited a very small contribution to the CP oxidation while the electron transfer processes (ETP) played the major role in the DB-SiOC/PMS system. The electron shuttles from the electron-donating CP molecules to the adjacent DB-SiOC/PMS* could be efficiently triggered viaSi-O bonds as bridges, making it possible for ultrafast oxidation of CP. In addition, the hollow-disc shaped DB-SiOC provided the biomorphic DE structures with abundant pores for enriching the PMS and pollutants, thus further accelerating the oxidation reaction. This work provided a new routine for the fabrication of Si-O doped carbon-based catalysts with excellent Fenton-like catalytic activity, which would greatly promote their application prospects in Fenton-like systems.

Na4MnAl(PO4)3(NMAP) with cheap price, high voltage plateaus and appreciable theoretical capacity has caused growing concern as cathode for sodium-ion batteries (SIBs). But it is still burdened with the inferior ion-diffusion kinetics and the Jahn-Teller distortions, which would result in unsatisfactory capacity and rapid capacity decay. Herein, we present an Mg2+doping strategy to conquer the above crucial obstacles and carry out a systematic investigation of how the Mg doping affect the sodium storage performance of NMAP. The findings indicate that this method endows the materials with boosted electrode reaction kinetics and structural stability. Consequently, the composites show visible enhancements in the electrochemical performance after the introduction of Mg. The optimal Mg doped sample (Mg0.10-NMAP/C) presents a high discharge capacity of 105.1 mAh g−1and an acceptable energy density of 360.5 Wh kg−1at 0.1 C, as compared with those (91.4 mAh g−1and 308 Wh kg−1) of undoped NMAP/C. Besides, the introduction of Mg contributes to higher capacity retention after 100 cycles at 0.2 C (57.7 % for NMAP/C, vs. 73.8 % for Mg0.10-NMAP/C). Our study offers a valuable strategy to modify NMAP with improved electrochemical performance, which would accelerate its course of commercial application.

In this paper, we propose a novel fuzzy matching data sharing scheme named FADS for cloud-edge communications. FADS allows users to specify their access policies, and enables receivers to obtain the data transmitted by the senders if and only if the two sides meet their defined certain policies simultaneously. Specifically, we first formalize the definition and security models of fuzzy matching data sharing in cloud-edge environments. Then, we construct a concrete instantiation by pairing-based cryptosystem and the privacy-preserving set intersection on attribute sets from both sides to construct a concurrent matching over the policies. If the matching succeeds, the data can be decrypted. Otherwise, nothing will be revealed. In addition, FADS allows users to dynamically specify the policy for each time, which is an urgent demand in practice. A thorough security analysis demonstrates that FADS is of provable security under indistinguishable chosen ciphertext attack (IND-CCA) in random oracle model against probabilistic polynomial-time (PPT) adversary, and the desirable security properties of privacy and authenticity are achieved. Extensive experiments provide evidence that FADS is with acceptable efficiency.

Conventional analytic techniques that measure ensemble averages and static disorder provide essential knowledge of the reaction mechanisms of organic and organometallic reactions. However, single-molecule junctions enable the in situ, label-free and non-destructive sensing of molecular reaction processes at the single-event level with an excellent temporal resolution. Here we deciphered the mechanism of Pd-catalysed Suzuki–Miyaura coupling by means of a high-resolution single-molecule platform. Through molecular engineering, we covalently integrated a single molecule Pd catalyst into nanogapped graphene point electrodes. We detected sequential electrical signals that originated from oxidative addition/ligand exchange, pretransmetallation, transmetallation and reductive elimination in a periodic pattern. Our analysis shows that the transmetallation is the rate-determining step of the catalytic cycle and clarifies the controversial transmetallation mechanism. Furthermore, we determined the kinetic and thermodynamic constants of each elementary step and the overall catalytic timescale of this Suzuki–Miyaura coupling. Our work establishes the single-molecule platform as a detection technology for catalytic organochemistry that can monitor transition-metal-catalysed reactions in real time.

LiMn2O4is a very important cathode material in the field of plug-in hybrids. However, it has limited large-scale practical application because of its severe electrode polarization and rapid capacity decay. By means of synergistic enhancement of double-cation (Na+, Mg2+) doping and three-dimensional graphene (3DG) coating, the Li0.94Na0.06Mg0.08Mn1.92O4/3DG composite cathode material was successfully synthesized via hydrothermal synthesis, high-temperature solid-phase sintering, and freeze-drying. Electrochemical test results display that the initial discharge specific capacity of the Li0.94Na0.06Mg0.08Mn1.92O4/3DG material reaches 146 mAh/g (137 mAh/g for LiMn2O4) at 0.5C, and the specific capacity remains at 130 mAh/g after 100 cycles (99 mAh/g for LiMn2O4). At 10C, the initial discharge specific capacity of the Li0.94Na0.06Mg0.08Mn1.92O4/3DG material is 90 mAh/g (69 mAh/g for Li0.94Na0.06Mg0.08Mn1.92O4and 38 mAh/g for LiMn2O4), which should be resulted from the synergistic enhancement of double-cation (Na+, Mg2+) doping and 3DG coating. Na+, Mg2+codoping effectively expands the Li+diffusion path and the diffusion coefficient of Li0.94Na0.06Mg0.08Mn1.92O4/3DG, and inhibits the dissolution of Mn3+. 3DG coating effectively improves the conductivity and reduces electrode polarization during the charge and discharge course. In addition, 3DG coating also plays an important role in inhibiting the dissolution of Mn3+.

Background: Parkinson’s disease (PD) is a progressive neurodegenerative disease for which there is no cure. In a clinical trial, the glucagon-like peptide-1 (GLP-1) receptor agonist exendin-4 has shown good protective effects in PD patients. The hormone glucose-dependent insulinotropic polypeptide (GIP) has also shown protective effects in animal models of PD.Objective: We tested DA-CH5, a novel dual GLP-1/GIP receptor agonist.Methods: DA-CH5 activity was tested on cells expressing GLP-1, GLP-2, GIP or glucagon receptors. The ability to cross the blood-brain barrier (BBB) of DA-CH5, exendin-4, liraglutide or other dual receptor agonists was tested with fluorescein-labelled peptides. DA-CH5, exendin-4 and liraglutide were tested in the MPTP mouse model of PD.Results: Analysing the receptor activating properties showed a balanced activation of GLP-1 and GIP receptors while not activating GLP-2 or glucagon receptors. DA-CH5 crossed the BBB better than other single or other dual receptor agonists. In a dose-response comparison, DA-CH5 was more effective than the GLP-1 receptor agonist exendin-4. When comparing the neuroprotective effect of DA-CH5 with Liraglutide, a GLP-1 analogue, both DA-CH5 and Liraglutide improved MPTP-induced motor impairments. In addition, the drugs reversed the decrease of the number of neurons expressing tyrosine hydroxylase (TH) in the SN, alleviated chronic inflammation, reduced lipid peroxidation, inhibited the apoptosis pathway (TUNEL assay) and increased autophagy -related proteins expression in the substantia nigra (SN) and striatum. Importantly, we found DA-CH5 was superior to Liraglutide in reducing microglia and astrocyte activation, improving mitochondrial activity by reducing the Bax/Bcl-2 ratio and normalising autophagy as found in abnormal expression of LC3 and p62.Conclusion: The results demonstrate that the DA-CH5 is superior to liraglutide and could be a therapeutic treatment for PD.

LigY belongs to the amidohydrolase superfamily responsible for the C–C bond fission of meta-cleavage products (MCPs). LigY employs similar nucleophile-activation strategies like previously reported serine-dependent MCP hydrolases; however, the mechanisms of the tautomerization and hydrolysis are different. In this study, the quantum mechanics/molecular mechanics (QM/MM) approach was performed to elucidate the mechanism of MCP C–C bond fission by LigY. The binding (monodentate or bidentate) of the substrate to a zinc ion plays a significant role in the tautomerization. Both binding modes could complete the tautomerization and hydrolysis; however, the monodentate mode and five-coordination might be the most likely binding mode. For the bidentate binding mode, unlike the mechanism proposed based on experiments, Tyr190 acts as a “proton transfer” bridge to complete the tautomerization and indirectly activates the catalytic water. For the monodentate binding mode, interestingly, Tyr190/Arg234* (from the neighboring protomer B) act as a proton donor for the activated deprotonated water required to complete the tautomerization. A strong hydrogen bond is formed in this step to stabilize the water and prevent it from moving away from the substrate (C6-carbonyl), leading to the subsequent C–C bond fragmentation. Furthermore, Arg72 plays a crucial role in the monodentate binding of the substrate to Zn(ii). Our work expanded the understanding of the mechanism of MCP C–C bond fragmentation by LigY, especially details of the tautomerization and substrate-assisted activation prior to C–C bond fission.

In this work, the carbon nanotubes (CNTs) encapsulating Zn and Fe bimetallic nanoparticles (FeZn@NC) were synthesized through a one-pot pyrolytic strategy. The persulfate (PS) activation ability of FeZn@NC with various ratios of Fe and Zn was determined by sulfamethoxazole (SMX) degradation. The results indicated that the iron played a key role in forming external CNTs and the catalytic activity of FeZn@NC was mainly based on the encapsulated FeZn nanoparticles. In addition, PS activation was greatly strengthened by the heterostructure of FeZn@NC. Free radical quenching experiments and electron paramagnetic resonance (EPR) spectra suggested that the singlet oxygen was the key reactive oxygen species for SMX degradation. The activity of pyridinic-N, pyrrolic-N and graphitic-N on external CNTs was analyzed by theoretical calculations, which showed the pyridinic-N possessed strong adsorptive ability to activate PS to degenerate sulfate radicals.

Ultra-high nickel ternary cathode material with high energy density is a very important material to meet the long driving range of new energy vehicles. However, cobalt has high toxicity, high price and supply chain risks, so the material is being developed in the direction of low cobalt or no cobalt. For ultra-high nickel cobalt free cathode material with high theoretical capacity (LiNi0.9Mn0.1O2, NM90), the lattice collapse and particle fragmentation caused by microcracks during long cycle will lead to inferior rate performance and cycle life. At present, the effect of different cobalt content on structure and electrochemical properties of cobalt-free cathode material is rarely reported. Therefore, based on cobalt-free precursors, the effects of proper Co doping on structure and electrochemical properties of NM90 material are studied in depth. It showed that proper Co doping can effectively reduce cationic mixing and improve Li+diffusion rate of NM90 material. The NM90–1.5%Co material exhibits discharge specific capacity of 167.1 mA h g−1after 100 cycles at 1C and 121.2 mA h g−1after 200 cycles at 5C, respectively. Furthermore, NM90–1.5%Co material shows an initial discharge specific capacity of 144.1 mA h g−1at 10C. Therefore, Co doping provides a feasible way to improve the structural stability and electrochemical performances of ultra-high nickel cobalt free cathode material.

An in-depth understanding of the links between the phase structure and electrochemical property is crucial for the advancement of high-performance anode materials. Herein, the sodium storage performance and mechanisms of MnO2with four distinct phase structures (α, β, γ, and δ) as anodes are systematically investigated. Among the four materials, the layered δ-MnO2nanoflowers exhibit the best sodium storage performances, characterized by a specific capacity of 303.6 mA h g–1after 100 cycles at 200 mA g–1, cyclability of 247.3 mA h g–1after 500 cycles at 1000 mA g–1, and high-rate performance of 184.5 mA h g–1at 3000 mA g–1. Furthermore, δ-MnO2shows the most pronounced pseudocapacitance behavior during discharge/charge processes among the four materials. Ex situXRD and TEM analyses reveal that the sodium storage reactions of α-, β-, and γ-MnO2proceed via a conversion reaction mechanism, while the sodium storage reaction of δ-MnO2is controlled by an insertion/deinsertion mechanism. The findings presented in this study may offer insights into the structure regulation and performance promotion of MnO2-based anode materials for SIBs.

Commercial herbicides, particularly sulfonylureas, are used worldwide and pose a significant challenge to environmental sustainability. The efficient degradation of sulfonylurea herbicides is critical. SulE, an esterase isolated from the bacterial strain Hansschlegelia zhihuaiaeS113, shows degradation activity toward sulfonylurea herbicides. However, the detailed catalytic mechanism remains vague to a large extent. Herein, we decipher the SulEP44R-catalyzed degradation mechanism of sulfonylurea herbicides using hybrid quantum mechanics and molecular mechanics approaches. Our results show that the degradation of sulfonylureas catalyzed by SulEP44Rinvolves four concerted elementary steps. The rate-determining step has an energy barrier range of 19.7–21.4 kcal·mol–1, consistent with the experimentally determined range of 16.0–18.0 kcal·mol–1. Distortion/interaction analysis demonstrates that active-site amino acids play a vital role in the enzymatic catalytic efficacy. The unique architecture of SulEP44R’s active site can serve as an excellent template for designing artificial catalysts. Key structural and charge parameters affecting catalytic activity were systematically screened and identified. Based on the elucidated degradation mechanism, several new herbicides with both high herbicidal activity and biodegradability were developed with the aid of a high-throughput strategy. Our findings may advance the application of sulfonylurea herbicides within the framework of environmental sustainability.

It is well known that cationic polymers have excellent antimicrobial capacity accompanied with high biotoxicity, to reduce biotoxicity needs to decrease the number of cationic groups on polymers, which will influence antimicrobial activity. It is necessary to design a cationic polymer mimic natural antimicrobial peptide with excellent antibacterial activity and low toxicity to solve the above dilemma. Here, we designed and prepared a series of cationic poly(β-amino ester)s (PBAEs) with different cationic contents, and introducing hydrophobic alkyl chain to adjust the balance between antimicrobial activity and biotoxicity to obtain an ideal antimicrobial polymer. The optimum one of synthesized PBAE (hydrophilic cationic monomer (HCM):hydrophobic monomer (HBM) = 5:5) was screened by testing cytotoxicity and minimum inhibitory concentration (MIC), which can effectively kill S. aureus and E. coli with PBAE concentration of 15 μg/mL by a spread plate bacteriostatic method and dead and alive staining test. The way of PBAE killing bacterial was destroying the membrane like natural antimicrobial peptide observed by scanning electron microscopy (SEM). In addition, PBAE did not exhibit hemolysis and cytotoxicity. In particular, from the result of animal tests, the PBAE was able to promote healing of infected wounds from removing mature S. aureus and E. coli on the surface of infected wound. As a result, our work offers a viable approach for designing antimicrobial materials, highlighting the significant potential of PBAE polymers in the field of biomedical materials.

The ultra-high nickel cathode material has important application prospect in power lithium-ion batteries. However, the poor structural stability and serious surface/interfacial side reactions during long cycles severely hinder the material's practical application. In this paper, Cs+doping and polymethyl methacrylate (PMMA) coating are used to synergistically modify the NCM955 material. The results show that the corresponding discharge specific capacity of NCMCs-2@P-2 material reaches 152.02 mAh/g at 1 C (1 C = 200 mA/g) and 125.66 mAh/g at 5 C after 300 cycles, and the capacity retention is 78.11% and 72.21%, respectively. In addition, it still maintains 156.36 mAh/g discharge specific capacity at 10 C, and these rate and cycle properties exceed those reported on ultra-high nickel cathode material. Moreover, NCMCs-2@P-2 material has higher migration energy barrier of Ni2+and lower migration energy barrier of Li+than that of NCM955 material. Therefore, NCMCs-2@P-2 material has excellent electrochemical properties, which has been proved by a series of structural characterization, theoretical calculation and performance test. The synergistic enhancement of Cs+doping and PMMA coating accelerates lithium ion diffusion kinetics, stabilizes crystal structure, and inhabits surface/interface side reaction.

Enzymes containing heme, nonheme iron, or copper active sites play an essential role in the dioxygen binding and activation for substrate oxidation. The conceptual challenges to the quantitative modeling of this primary catalytic step arise from (1) instrinsic electronic nonadiabaticity of the spin flip events of the triplet dioxygen molecule (3O2), mediated by spin–orbit coupling and (2) possible heat dissipation channels, due to the high exothermicity of dioxygen binding processes. Herein, the spin-forbidden dioxygen binding dynamics of a reduced heme model was directly investigated in terms of the nonadiabatic trajectory surface-hopping dynamics, involving the coupled singlet, triplet and quintet states. This work reveals the complexity of this elemental reaction, and the binding/dissociation dynamics of iron peroxo species is important to interpret the subsequent H atom abstraction reaction step. Furthermore, we identify nonadiabatic dynamical effects that could not be observed through traditional calculations of static geometries.

A simple, rapid and sensitive immunogold chromatographic strip test based on a monoclonal antibody was developed for the detection of melamine (MEL) residues in raw milk, milk products and animal feed. The limit of detection was estimated to be 0.05 μg/mL in raw milk, since the detection test line on the strip test completely disappeared at this concentration. The limit of detection was 2 μg/mL (or 2 μg/g) for milk drinks, yogurt, condensed milk, cheese, and animal feed and 1 μg/g for milk powder. Sample pretreatment was simple and rapid, and the results can be obtained within 3–10 min. A parallel analysis of MEL in 52 blind raw milk samples conducted by gas chromatography–mass spectrometry showed comparable results to those obtained from the strip test. The results demonstrate that the developed method is suitable for the onsite determination of MEL residues in a large number of samples.

In this work, sea urchin-like micro/nano anatase titanium dioxide (TiO2) spheres are fabricated by a facile hydrothermal method and subsequent heat treatment in N2atmosphere. Benefiting from the unique micro/nano-spheres structure, large specific surface area, and rich oxygen vacancies, this sea urchin-like micro/nano TiO2spheres exhibit excellent long-cycle stability (204.5 mAh g−1after 1000 cycles at 1.0 A g−1, with a capacity retention rate of 93.3 %) and superior high-rate performance (137.2 mAh g−1at 10.0 A g−1). Even at 10.0 A g−1for 20,000 cycles, it still maintains a reversible specific capacity of 120.5 mAh g−1. CV, EIS and GITT analysis demonstrate that the TiO2nanospheres exhibit obvious pseudocapacitive behavior, stable reaction kinetics and large Na+diffusion coefficient during the discharge/charge process. More importantly, the Na-ion full cell assembled with NaVPO4F as a cathode material and TiO2nanospheres as an anode material also exhibit good cycling stability (142.7 mAh g−1after 100 cycles at 0.5 A g−1).

Deoxynivalenol (DON) is a common mycotoxin that induces intestinal inflammation and oxidative damage in humans and animals. Given that lithocholic acid (LCA) has been suggested to inhibit intestinal inflammation, we aimed to investigate the protective effects of LCA on DON-exposed porcine intestinal epithelial IPI-2I cells and the underlying mechanisms. Indeed, LCA rescued DON-induced cell death in IPI-2I cells and reduced DON-stimulated inflammatory cytokine levels and oxidative stress. Importantly, the nuclear receptor PPARγ was identified as a key transcriptional factor involved in the DON-induced inflammation and oxidative stress processes in IPI-2I cells. The PPARγ function was found compromised, likely due to the hyperphosphorylation of the p38 and ERK signaling pathways. In contrast, the DON-induced inflammatory responses and oxidative stress were restrained by LCA via PPARγ-mediated reprogramming of the core inflammatory and antioxidant genes. Notably, the PPARγ-modulated transcriptional regulations could be attributed to the altered recruitments of coactivator SRC-1/3 and corepressor NCOR1/2, along with the modified histone marks H3K27ac and H3K18la. This study emphasizes the protective actions of LCA on DON-induced inflammatory damage and oxidative stress in intestinal epithelial cells via PPARγ-mediated epigenetically transcriptional reprogramming, including histone acetylation and lactylation.

This study aimed to investigate the potential of fibroblast activation protein (FAP) as a biomarker in the progression of oral leukoplakia (OLK) carcinogenesis. This was achieved by evaluating FAP expression at different levels of the organisation, namely oral normal mucosa (NM), OLK, and oral squamous cell carcinoma (OSCC).

LiNi0.95Co0.04Mn0.01O2cathode material is modified by bulk W-doping and surface Co-doping through a scalable co-precipitation-calcination process. A small amount of the dopants has no negative impact on specific capacity of the ultrahigh-Ni cathode, but significantly improves the structural stability and electrochemical performance. The modified sample delivers an initial discharge capacity of 228.3 mAh g−1at 0.1 C (1 C = 220 mA g−1) and exhibits a capacity retention of 84.7 % after 300 cycles at a current density of 2 C and excellent rate capability (188.6 mAh g−1at 5 C), demonstrating its practicability in high-energy-density lithium-ion batteries. X-ray photoelectron spectroscopy result shows that the collaborative modification can maintain a high Ni3+content on the surface of the material. Furthermore, differential capacity analysis and electrode kinetic study suggest that the increase of polarization during cycling is suppressed and the structural stability is improved.

Aim:HLA-A*24:02is significantly associated with cutaneous adverse drug reactions caused by aromatic antiepileptic drugs. Here, we aimed to establish a fast and reliable detection method for HLA-A*24:02genotyping. Methods:A single-tube multiplex quantitative real-time polymerase chain reaction (qPCR) assay for HLA-A*24:02genotyping was established by combining allele-specific primers with TaqMan probes. Results:A 100% concordance was observed between qPCR and SBT result in 106 Han subjects. The detection limit of the new method was 0.05 ng DNA. The positive rate of HLA-A*24:02in Tibetans (55.6%, n = 81) was significantly higher than those in Han (34%, n = 106), Uighur (27.5%, n = 102), Bouyei (25.9%, n = 116) and Miao populations (26.5%, n = 113). Conclusion:The newly established qPCR assay was reliable for HLA-A*24:02screening in clinical applications.

Fe-based oxides have been recognized as one of the most promising anode materials for lithium-ion batteries (LIBs) due to their theoretical capacities, low cost, eco-friendliness, and natural abundance. However, poor cycling stability and low rate capability severely hindered their practical applications. Compared to single-component materials, multicomponent composites are more capable of achieving optimal electrochemical performance for electrode materials due to their synergetic effect. In this work, a novel ternary Fe2O3/Fe3O4/FeCO3composite is fabricated by a facile hydrothermal method with FeCl2·4H2O and urea as raw materials. When evaluated as an anode material for LIBs, this ternary Fe2O3/Fe3O4/FeCO3composite exhibits excellent rate capability (with reversible capacities of 624, 488, and 270 mAh g–1at 1.0, 3.0, and 10.0 A g–1, respectively) and remarkable cycling stability (with a reversible capacity of 779 mAh g–1after 300 cycles at 0.5 A g–1and 410 mAh g–1after 800 cycles at 3.0 A g–1), which are much superior to those of the single-component Fe2O3material. It is found that the ternary Fe2O3/Fe3O4/FeCO3composite possesses good structural integrity during cycling and fast electrochemical reaction kinetics, which result in excellent long-term cycling stability and enhanced high-rate capability. The results may provide clues for the rational structural design of high-performance Fe-oxide anode materials for next-generation LIBs.

The metabolic activation and transformation of naphthalene by the cytochrome P450 enzyme (CYP 1B1) plays an important role in its potential carcinogenicity. The process has been explored by a quantum mechanics/molecular mechanics (QM/MM) computational method. Molecular dynamic simulations were performed to explore the interaction between naphthalene and CYP 1B1. Naphthalene involves α- and β-carbon, the electrophilic addition of which would result in different reaction pathways. Our computational results show that both additions on α- and β-carbon can generate naphthalene 1,2-oxide. The activation barrier for the addition on β-carbon is higher than that for the α-carbon by 2.6 kcal·mol–1, which is possibly caused by the proximity between β-carbon and the iron-oxo group of Cpd I in the system. We also found that naphthalene 1,2-oxide is unstable and the O–C bond cleavage easily occurs via cellular hydronium ion, hydroxyl radical/anion; then it will convert to the potential ultimate carcinogen 1,2-naphthoquinone. The results demonstrate and inform a detailed process of generating naphthalene 1,2-oxide and new predictions for its conversion.

Hydrated V2O5has attracted considerable attention for sodium ion batteries (SIBs) due to its high theoretical capacity. However, the poor cycling performance caused by structural instability during sodiaton/desodiation greatly hampers its application. Herein, Y3+pre-intercalated hydrated V2O5samples (YxV2O5, x = 0.0, 0.02 and 0.06) are synthesized by a facile sol-gel and freeze-drying routes followed by heat treatment in air at 200 °C. It is found that the morphology, oxidation state of vanadium, and sodium storage performance of hydrated V2O5could be largely modulated by Y3+pre-intercalation. As cathode material for SIBs, the Y0·02V2O5sample exhibits much enhanced cycling stability, higher Na+diffusion coefficient, lower electrochemical reaction resistance, and improved rate capability compared to the pure V2O5counterpart. First-principle calculations reveals that the pre-intercalated Y3+forms [YO6] pillar with two oxygen atoms from the VO5pyramids and four oxygen atoms from the intercalated water molecules, which firmly binds the V2O5double layers together. Ex-situ XRD, SEM, and TEM analysis demonstrate that Y3+pre-intercalation effectively strengthens the structural integrity, stabilizes the layered structure, and suppress the irreversible phase transition of hydrated V2O5during repeated discharge/charge cycling, and therefore leading to enhanced cycling stability and improved rate capability.

An extradiol-cleaving catecholic dioxygenase, 2,3-dihydroxybiphenyl dioxygenase, plays important roles in the catabolism of biphenyl/polychlorinated biphenyl aromatic contaminants in the environment. To better elucidate the biodegradable pathway, a theoretical investigation of the ring-opening degradation of 2,3-dihydroxybiphenyl (DHBP) was performed with the aid of quantum mechanical/molecular mechanical calculations. A quintet state of the DHBP–iron–dioxygen group adducts was found to be the reactive state with a substrate radical–FeII–superoxo (DHBP•↑–FeII–O2•–↓) character. The HOO•species was the reactive oxygen species responsible for the subsequent attack of DHBP. Among the whole reaction energy profile, the first step in proton-coupled electron transfer was determined to be the rate-determining step with a potential energy barrier of 17.2 kcal/mol, which is close to the experimental value (14.7 kcal/mol). Importantly, the residue His194 shows distinct roles in the catalytic cycle, where it acts as an acid–base catalyst to deprotonate the hydroxyl group of DHBP at an early stage, then stabilizes the negative charge on the dioxygen group, and, at the final stage, promotes the semialdehyde product formation as a proton donor.

In the automatic detection for surface defects of optical components, the digs and dust particles exhibit similar features: point-like shape and variable intensity reflectivity. On this condition, these two types with entirely different damages are easily confused so that misjudgments will be induced. To solve this problem, a polarization-characteristics-based classification method of digs and dust particles (PCCDD) is proposed based on the polarimetric imaging technique and dark-field imaging technique. First, a dark-field imaging system equipped with a polarization state generator (PSG) and a polarization state analyzer (PSA) is employed to measure and establish normalized Mueller matrices’ datasets of digs and dust particles. And by a nonlinear global search combined with a separability evaluation method, the optimal number of acquisitions and corresponding polarization measurement states of the PSG and the PSA are obtained, as well as the parameters of classification function. Then, multiple polarization images are acquired under the optimal states to extract a multidimensional feature description that relates only to the polarization characteristics of the defect; this subsequently acts as the input vector of the classifier to finally achieve the classification. This method takes full advantage of both the difference in polarization properties between digs and dust particles and the characteristic that the polarization properties of digs are relatively invariant while those of dust particles have a large variability. The classification process involves only simple matrix operations. Compared to the traditional discrimination method based on intensity images, the features obtained by this method have a higher separability. Experiments show that the classification accuracy reaches over 90%. This method can be further applied to the recognition and discrimination of other defects in the field of surface defects’ detection.

N-Doped carbon nanotubes encapsulating bimetallic Fe/Mn nanoparticles (FeMn@NCNTs) were fabricated after a one-step pyrolysis and were used as the catalyst for peroxymonosulfate activation to degrade acetamiprid. The FeMn@NCNTs showed uniform nanotubes with rich N doping and the encapsulated FeMn nanoparticles were doubly protected by both NCNTs and a clingy graphitic structure. The results indicated that the confined FeMn nanoparticles were designated as Fe2.7Mn0.3C according to the XRD pattern and elemental composition. Radical quenching indicated that SO4−and OH were the dominant radicals in the FeMn@NCNTs/PMS system. The indispensable roles of both radical pathways of O2−and non-radical 1O2in the superior catalytic performance were also confirmed. As a result, both the embedded FeMn nanoparticles and NCNTs in FeMn@NCNTs contributed to the acetamiprid degradation with multiple degradation mechanisms. XPS results confirmed the formation of redox cycles between the multiple valence states of Mn and Fe, which ensured the superior catalytic activity of FeMn@NCNTs for PMS activation. In addition, only a small decrease in the catalytic performance from 99.5% to 90% was observed after four cycles. The catalytic activity of used FeMn@NCNTs was mostly recovered after heat regeneration (350 °C), which exhibited the excellent stability and reusability of the FeMn@NCNTs.

Cytoplasmic male sterility (CMS) plays an important role in the production of soybean hybrid seeds. MicroRNAs (miRNAs) are a class of non-coding endogenous ~ 21 nt small RNAs that play crucial roles in flower and pollen development by targeting genes in plants. To dissect the function of miRNAs in soybean CMS, a total of 558 known miRNAs, 10 novel miRNAs, and 466 target genes were identified in flower buds of the soybean CMS line NJCMS1A and its restorer line NJCMS1C through small RNA sequencing and degradome analysis. In addition, miRNA-mediated editing events were also observed, and the two most frequently observed editing types (A → G and C → U) were validated by cloning and sequencing. And as the base editing occurred, some targets were filtered, such as gma-miR2118b-P6GT with Glyma.08G122000.2. Further integrated analysis of transcriptome and small RNA found some miRNAs and their targets’ expression patterns showing a negative correlation, such as gma-miR156b/GmSPL9aand gma-miR4413b/GmPPR. Furthermore, opposite expression pattern was observed between gma-miR156b and GmSPL9during early stage of flower bud development. Taken together, the regulatory network of gma-miR156b/GmSPL9and gma-miR4413b/GmPPRwith flower bud development in soybean CMS was developed. Most importantly, previous reports showed that these targets might be related to pollen development and male sterility, suggesting that both conserved and species-specific miRNAs might act as regulators of flower bud development in soybean CMS. These findings may provide a better understanding of the miRNA-mediated regulatory networks of CMS mechanisms in soybean.