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Similar to surfaces of three-dimensional (3D) bulk materials, edges are inevitable in 2D materials and have been studied a lot (e.g., for MoS2). In the current work, taking the ambient-stable MoSi2N4as an example, nonpolar and polar edges as well as polar-edge reconstructions are studied based on first-principles calculations. We demonstrate that a combination of the “local” electron counting model (ECM) at edges and “nonlocal” charge polarity analysis (CPA) across the ribbon is essential for a unified understanding of the “local” edge properties and edge reconstructions in the following aspects. For pristine edges, the semiconducting (metallic) property of nonpolar armchair (polar zigzag) edges is related to CPA, and the spin-paired (spin-polarized) electronic structure of nonpolar (polar) edges is related to the ECM. For polar-edge reconstructions: (1) the polar edges become semiconducting when the reversed dipole from edge-reconstruction partially cancels the accumulated electric dipole within the ribbon; (2) the polar edges can further be spin-paired when edge-reconstruction fulfills the ECM for both the double cation (Mo, Si)-edge and the anion N-edge; and (3) ECM and CPA give the same conclusion for edge-reconstruction. Our analysis of combining ECM and CPA not only gives the general guidance for obtaining spin-paired and semiconducting polar edges but also potentially helps deepen the understanding of edges of other 2D layered materials.

Cerebral stroke is the second leading cause of death and the third leading cause of death and disability in the world, and more than half of these patients have hand dysfunction, making hand rehabilitation an urgent challenge. In this study, a system for hand rehabilitation therapy for stroke patients was designed using novel human-computer interaction technology. The system combines a brain-computer interface, a deep learning algorithm and a rehabilitation glove, and designs an electroencephalogram (EEG) signal acquisition card and a rehabilitation glove to realise the application of motor imagery therapy to the active rehabilitation of patients' hands. On the brain-computer interface-based motor imagery experiments, the Long Short Term Memory (LSTM) recurrent neural network algorithm designed in this study achieves an average accuracy of 95.78% for the classification accuracy of mental tasks in seven motor imagery modes, which is important for the active rehabilitation of patients with hand function based on motor imagery-driven rehabilitation.

4-Hydroxyphenylpyruvate dioxygenase (HPPD, EC 1.13.11.27) is one of the most promising herbicide targets for the development of agricultural chemicals owing to its unique mechanism of action in plants. We previously reported on the co-crystal structure of Arabidopsis thaliana(At) HPPD complexed with methylbenquitrione (MBQ), an inhibitor of HPPD that we previously discovered. Based on this crystal structure, and in an attempt to discover even more effective HPPD-inhibiting herbicides, we designed a family of triketone-quinazoline-2,4-dione derivatives featuring a phenylalkyl group through increasing the interaction between the substituent at the R1position and the amino acid residues at the active site entrance of AtHPPD. Among the derivatives, 6-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethyl-3-(1-phenylethyl)quinazoline-2,4(1H,3H)-dione (23) was identified as a promising compound. The co-crystal structure of compound 23with AtHPPD revealed that hydrophobic interactions with Phe392 and Met335, and effective blocking of the conformational deflection of Gln293, as compared with that of the lead compound MBQ, afforded a molecular basis for structural modification. 3-(1-(3-Fluorophenyl)ethyl)-6-(2-hydroxy-6-oxocyclohex-1-ene-1-carbonyl)-1,5-dimethylquinazoline-2,4(1H,3H)-dione (31) was confirmed to be the best subnanomolar-range AtHPPD inhibitor (IC50= 39 nM), making it approximately seven times more potent than MBQ. In addition, the greenhouse experiment showed favorable herbicidal potency for compound 23with a broad spectrum and acceptable crop selectivity against cotton at the dosage of 30–120 g ai/ha. Thus, compound 23possessed a promising prospect as a novel HPPD-inhibiting herbicide candidate for cotton fields.

Although N4-acetylcytidine (ac4C) modification affects the stability and translation of mRNA, it is unknown whether it exists in noncoding RNAs, and its biological function is unclear. Here, nucleotide-resolution method for profiling CTC-490G23.2 ac4C sites and gain- and loss-of-function experiments revealed that N-acetyltransferase 10 (NAT10) is responsible for ac4C modification of long noncoding RNAs (lncRNAs). NAT10-mediated ac4C modification leads to the stabilization and overexpression of lncRNA CTC-490G23.2 in primary esophageal squamous cell carcinoma (ESCC) and its further upregulation in metastatic tissues. CTC-490G23.2 significantly promotes cancer invasion and metastasis in vitro and in vivo. Mechanistically, CTC-490G23.2 acts as a scaffold to increase the binding of CD44 pre-mRNA to polypyrimidine tract-binding protein 1 (PTBP1), resulting in a oncogenic splicing switch from the standard isoform CD44s to the variant isoform CD44v(8-10). CD44v(8-10), but not CD44s, binds to and increases the protein stability of vimentin. Expression levels of CTC-490G23.2 and CD44v(8-10) can predict poor prognosis in cancer patients. Furthermore, the antisense oligonucleotide (ASO)/SV40-LAH4-L1 peptide self-assembled nanocomplexes targeting CTC490G23.2 exerts a significantly suppressive effect on cancer metastasis. The outcome of this study will provide new mechanistic insight into the ac4C modification of lncRNAs and useful clues for the development of novel systemic therapies and prognostic biomarkers.

Five new furanobutenolide-derived C19-norcembranoid diterpenes, sinudenoids A–E (1–5, respectively), were isolated from the soft coral Sinularia densa. Sinudenoid A (1) possesses an uncommon 5/5/11-fused tricyclic ring system. Sinudenoids B–D (2–4, respectively) share the same tetracyclic 5/5/6/6 ring system but represent two kinds of new skeletons. Sinudenoid E (5) is the second compound with the rare 8/8 bicyclic carbon core. A plausible biosynthesis pathway for compounds 1–6is proposed. Compound 5exhibits strong anti-inflammatory activity in the zebrafish model.

Pylephlebitis, which is a type of septic thrombophlebitis of the portal vein, is a rare and life-threatening complication that commonly occurs following appendicitis. However, nonspecific abdominal complaints and fever can impede the diagnosis of pylephlebitis. Timely use of appropriate antibiotics and anticoagulants is paramount for treating this condition. We present a case of pylephlebitis and septic shock caused by acute nonperforated appendicitis. A 32-year-old man presented with migratory right lower abdominal pain. Blood cultures showed the presence of Escherichia coli. Blood test results showed increased bilirubin concentrations and coagulation factor abnormalities. A computed tomographic abdominal scan showed that the portal vein had a widened intrinsic diameter. After intensive care treatment with antibiotics, antishock therapy, anticoagulants, and other supportive treatments, the infection was monitored, the abdominal pain disappeared, and the jaundice subsided. Laparoscopic appendectomy was performed. Histopathology showed acute suppurative appendicitis, and no abnormalities were observed during the follow-up period after discharge. A multidisciplinary approach is mandatory for the decision-making process in the presence of pylephlebitis caused by appendicitis to obtain a correct diagnosis and prompt treatment. Similarly, the timing of appendectomy is important for minimizing intra- and postoperative complications.

In the pond culture of Chinese mitten crabs (Eriocheir sinensis), high stocking densities usually increase the frequency of agonistic behavior, which can directly impact crab integrity, survival, and growth and result in economic losses. We hoped to reduce agonistic behavior by adding additives to feed. In this study, we first observed the agonistic behavior of E. sinensisin 5 molting periods (from first molting to puberty molting) during the adult grow-out stage. Then, we assessed the effects of L-TRP as a feed additive on the agonistic behavior of juvenile, precocious, subadult, and adult crabs. Finally, we performed 106 days of cage culture to assess the effects of L-TRP on feeding behavior, animal vitality, growth performance, and nutritional composition. The results showed that the intensity of agonistic behavior was significantly higher after puberty molting than in other molting periods during the adult grow-out stage. Moreover, L-TRP supplementation inhibited the agonistic behavior of juvenile, subadult, and adult crabs, but it did not affect the precocious crabs. During cage culture, L-TRP significantly improved crab vitality after 3 weeks but not after 6 and 9 weeks, but it reduced the ingestion rate after 9 weeks. Moreover, the L-TRP group showed a significant increase in the weight gain rate and specific growth rate after the fourth molting. After 106 days of culture, the content of proline and fatty acids in the muscle decreased significantly after L-TRP diet supplementation. Some long-chain polyunsaturated fatty acids also decreased significantly in the hepatopancreas. However, we must focus on the adverse effects of L-TRP on Pro and fatty acid composition. Further research is required on the balance between inhibition of agonistic behavior and effects of L-TRP on the nutritional quality of E. sinensis.

Direct laser deposition (DLD), as a popular metal additive manufacturing process, shows advantages of technical flexibility and high efficiency to gain a high-performance alloy steel component. However, during the processing of DLD, the deposited steel layer is affected by the subsequent layer depositing. The DLD block shows different microstructure and mechanical properties at the bottom, middle and top of the deposited parts. To date, there are few research works about the effects of inter-layer interval time and laser power on the microstructure evolution and mechanical properties of the deposited layers. In this study, the idle time and laser power layer by layer during DLD of 12CrNi2 steel were controlled to cause the deposited layers to maintain a high cooling rate, while the bottom deposited layer was subjected to a weak tempering effect. Results show that a high proportion of martensite is produced, which improves the strength of the deposited layer. Under the laser scanning strategy of laser power 2,500 W, scanning velocity 5 mm·s−1, powder feeding rate 11 g·min−1, overlap rate 50%, and a laser power difference of 50 W and a 2 min interval, the tensile strength of the deposited layer of 12CrNi2 steel is in the range of 873–1,022 MPa, and the elongation is in the range of 16.2%–18.9%. This study provides a method to reduce the tempering effect of the subsequent deposition layers on the bottom layers, which can increase the proportion of martensite in the low-alloy high-strength steel, so as to improve the yield strength of the alloy steel.

Abnormal expression of miR‐409‐3p has been found in several neurodevelopmental disorders, but whether it is dysregulated in the patients with acute cerebral infarction (ACI) has not been evaluated. The current study mainly focused on the clinical significance and the underlying mechanism of plasma miR‐409‐3p in the progression of ACI. The level of plasma miR‐409‐3p was determined in ACI patients (n = 80) and healthy controls (n = 30). Pearson correlation assay was performed to evaluate the association and cardiovascular risk factors. A receiver operating characteristic curve (ROC) was used to evaluate the diagnostic value of plasma miR‐409‐3p levels in patients with ACI. Dual luciferase reporter assay and western blot were performed to determine the possible target gene of miR‐409‐3p. Our data showed that the expression of plasma miR‐409‐3p in the ACI group was higher than that in the healthy controls. Furthermore, Pearson correlation analysis indicated a positive correlation between plasma miR‐409‐3p and the NIHSS score. ROC analysis indicated that plasma miR‐409‐3p could differentiate plasma miR‐409‐3p in ACI patients from healthy controls. Then, we explored the possible target genes of miR‐409‐3p. Interestingly, C1q and TNF‐related 3 (CTRP3), a novel adipose tissue‐derived secreted factor, was found to be a target gene of miR‐409‐3p. We found that knockdown of CTRP3 significantly induced PC12 cell apoptosis, even in PC12 cells transfected with miR‐409‐3p inhibitor. These data suggested that miR‐409‐3p induced PC12 cell apoptosis by targeting CTRP3. Altogether, elevated plasma miR‐409‐3p is correlated with disease severity and may be efficient for the early diagnosis of ACI.

Designing safer chemicals is an integral part of green chemistry that supports good health and well-being. The teaching of molecule design through relevant courses has important implications for the education of sustainable chemists. In these courses, training in toxicology and hazard assessment is essential for students to study benign chemical design that promotes social and environmental justices. However, toxicology training has been rarely included in the course of molecular design, and education of green molecular design at the postgraduate level has been less involved. In this study, we developed an online classroom for toxicology training as a new component of our chemical molecular design course. This class was designed to provide students with a toxicity perspective for viewing chemicals by integrating our three web-based tools. The average score of students’ attitude evaluation toward the web-based class was 4.0/5.0, indicating that the toxicology class achieved the expected effects and provided a good experience for students to learn about designing safer chemicals. This work may facilitate the education of green molecular design and inspire students to seriously consider chemically toxic side effects.

Four new diterpenoid alkaloids, nagaconitines A-D (1–4), were isolated from the roots of Aconitum nagarumvar. heterotrichum, one tranditional Chinese medicinal plan.

A new method was developed to optimize the microwave heating thickness of the spent automobile catalyst in order to improve the uniform distribution of the temperature field. The average penetration depth and the microwave heating thickness of the spent automobile catalyst were calculated by Gauss model and numerical calculation based on dielectric loss tangent and reflection loss. The results showed that the spent automobile catalyst was a medium loss material. The average penetration depth was 1.11 m from room temperature to 800 °C. The optimum microwave heating thickness of the spent automobile catalyst was about 0.83 m or 0.75 times of the average penetration depth. Industrial application analysis indicated that the optimization of heating thickness could improve the uniform distribution of the temperature field and reduce energy consumption.

Fragment-based drug design (FBDD) is a promising methodology to find quality drug leads. It is important in the curriculum of a drug design course due to its impact on drug discovery. However, teaching FBDD and its use by students remain challenging in most cases. A web-based laboratory class to teach FBDD in the form of our copyrighted workshops is described. The students’ feedback and a quantitative evaluation of the results show that the web-based laboratory class is popular with students and facilitates students’ learning of FBDD for design of possible drug-like molecules.

RtcB, a highly conserved RNA ligase, is found in all three domains of life, and demonstrated to be an essential tRNA splicing component in archaea and metazoans. However, the biological functions of RtcB in bacteria, where there is no splicing, remains to be clarified. We first performed bioinformatics analysis which revealed highly conserved structures and presumably conserved functions of RtcB in bacteria. However, its orthologs only occur in ∼ 0.5% of bacterial species across diverse phyla with significant signals of frequent horizontal transfer, highlighting its non-essential role in bacteria. Next, by constructing an rtcB-knockout strain, we find that the removal of antibiotic stress induces a significant impact on rtcBexpression in wild-type strain, and furthermore the depletion of RtcB (ARtcB strain) delays the recovery process. Our transcriptomic analysis, comprising the 3′-end labeling of RNAs, highlights a significant increase in unmapped reads and cleaved rRNAs in the Δ RtcB strain, particularly during recovery. Our observations suggest that the conserved RNA ligase RtcB, repairs damaged rRNAs following stress, which potentially saves energy and accelerates recovery of its host. We propose that acquisition of RtcB by diverse bacterial taxa provides a competitive advantage under stressful conditions.

The lethal chronic airway infection of the cystic fibrosis(CF) patients is predisposed by colonization of specific CF-philic pathogens or the CF microbiomes, but key processes and reasons of the microbiome settlement in the patients are yet to be fully understood, especially their survival and metabolic dynamics from normal to diseased status under treatment. Here, we report our meta-analysisresults on CF airway microbiomesbased on metabolic networks reconstructed from genome information at species level. The microbiomes of CF patients appear to engage much more redox-related activities than those of controls, and by constructing a large dataset of anti-oxidative stress (anti-OS) genes, our quantitative evaluation of the anti-OS capacity of each bacterial species in the CF microbiomes confirms strong conservation of the anti-OS responses within genera and also shows that the CF pathogens have significantly higher anti-OS capacity than commensals and other typical respiratory pathogens. In addition, the anti-OS capacity of a relevant species correlates with its relative fitness for the airways of CF patients over that for the airways of controls. Moreover, the total anti-OS capacity of the respiratory microbiome of CF patients is collectively higher than that of controls, which increases with disease progression, especially after episodes of acute exacerbation and antibiotic treatment. According to these results, we propose that the increased OS in the airways of CF patients may play an important role in reshaping airway microbiomes to a more resistant status that favors the pre-infection colonization of the CF pathogens for a higher anti-OS capacity.

Charge transfer is of particular importance in manipulating the interface physics in transition-metal oxide heterostructures. In this work, we have fabricated epitaxial bilayers composed of polar 3d LaMnO3and nonpolar 5d SrIrO3. Systematic magnetic measurements reveal an unexpectedly large exchange bias effect in the bilayer, together with a dramatic enhancement of the coercivity of LaMnO3. Based on first-principle calculations and X-ray absorption spectroscopy measurements, such a strong interfacial magnetic coupling is found closely associated with the polar nature of LaMnO3and the strong spin–orbit interaction in SrIrO3, which collectively drive an asymmetric interfacial charge transfer and lead to the emergence of an interfacial reentrant spin/superspin glass state. Our study provides a new insight into the charge transfer in transition-metal oxide heterostructures and offers a novel means to tune the interfacial exchange coupling for a variety of device applications.

The phenomenon of knowledge modularity exists in the executing process of enterprise business, and the performance of business execution depends on the ability of knowledge modules. Therefore, it is of great theoretical value to study the evolution of knowledge modules and their integrated contexts. In order to help enterprises to optimize their configuration of knowledge contexts, a method of dynamic knowledge context modeling was proposed in the article. The dynamic evolution process of the knowledge modules context from the perspective of context was discussed, and the dynamic evolution characteristics of the context based on business problems was studied. Also the contextual evolution model was established, which could effectively improve the cooperative efficiency of knowledge resources and enhance the performance of enterprise business process execution.

The conventional layered-growth modes of atom/small molecule self-assembly on solid surfaces are usually obtained from the “mean field approximation” description of adsorbate–substrate interactions, which neglected the differences in kinetic parameters between different adsorption configurations. Here, through a multiscale computational method, we showed a novel mixed layered self-assembly growth of C60molecules on an oxygen-passivated Fe(001)-p(1 × 1)O substrate through considering differences in kinetic parameters between adsorption configurations in detail. The simulated mixed growth is consistent with the experimental observation (Picone, et al. Appl. Mater. Interfaces2016, 8, 26418) in which regions of large C60islands that have been nucleated coexist with areas of well-separated C60molecules. With a simple general model, the mixed layered-growth mode can be applied for other large molecules’ self-assembly, provided that the multidegrees of freedom in adsorption configurations give distinct growth parameters and the molecule is weakly chemisorbed on the substrate. Our study demonstrates the existence of a novel layered-growth mode, the mixed layered-growth mode, in addition to the conventional layered-growth modes.

Cancer cells associated with radioresistance are likely to give rise to local recurrence and distant metastatic relapse. However, it remains unclear whether specific miRNAs have direct roles in radioresistance and/or prognosis. In this study, we find that miR-339-5p promotes radiosensitivity, and is downregulated in radioresistant subpopulations of esophageal cancer cells. Notably, miR-339-5p was selectively secreted into blood via exosomes, and that higher serum miR-339-5p levels were positively associated with radiotherapy sensitivity and good survival. Moreover, miR-339-5p expression was downregulated in the T3/T4 stage compared with T1/T2 stage in esophageal squamous cell carcinoma (ESCC) patients (P= 0.04), and low miR-339-5p expression in tissue was significantly associated with poor overall survival (P= 0.036) and disease-free survival (P= 0.037). Overexpression of miR-339-5p enhanced radiosensitivity in vitro and in vivo. Mechanistically, miR-339-5p enhances radiosensitivity by targeting Cdc25A, and is transcriptionally regulated by Runx3. Correlations were observed between miR-339-5p levels and Cdc25A/Runx3 levels in tissue samples. Intriguingly, combined analysis of miR-339-5p expression with Runx3 increased the separation of the survival curves obtained for either gene alone in the TCGA datasets (P= 0.009). Overall, exosome-derived miR-339-5p mediates radiosensitivity through downregulation of Cdc25A, and predicts pathological response to preoperative radiotherapy in locally advanced ESCC, suggesting it could be a promising non-invasive biomarker for facilitating personalized treatments.

Over the past two decades, intramuscular lipids have been viewed as a cause of insulin resistance due to their ability to suppress insulin-stimulated glucose uptake in skeletal muscle. Zinc-α2-glycoprotein (ZAG) is an adipokine involved in lipolysis of white adipose tissue (WAT). To investigate the action of ZAG on insulin resistance induced by a high-fat diet (HFD), which affects the intramuscular fat, mice were divided into three groups, normal diet, HFD, and ZAG treatment under HFD (HFZ). The results showed that the insulin sensitivity of ZAG-treated mice was significantly improved. The body weight, WAT weight, and intramuscular fat were significantly decreased in the HFZ group compared with the HFD group. The lipolytic enzymes, including phosphorylation of hormone-sensitive lipase and adipose triglyceride lipase, were significantly upregulated in the skeletal muscle of mice that received the ZAG treatment compared with the HFD group. Insulin signaling proteins, such as phosphorylation of insulin receptor substrate 1 and cell membrane glucose transporter type 4, were also significantly increased in the skeletal muscle of the ZAG-treated group. Furthermore, a metabolic rate study showed that ZAG overexpression increases the respiratory exchange ratio and heat production. In vitro, ZAG treatment promotes glucose uptake and decreases intracellular lipids in C2C12 myotubes. Taken together, these data showed that overexpression of ZAG alleviates HFD-induced insulin resistance in mice, along with decreasing the lipid content of skeletal muscle.

Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that can cause severe diseases in pigs and result in enormous economic losses in the worldwide swine industry. Previous studies revealed that PEDV exhibits an obvious capacity for modulating interferon (IFN) signaling or expression. The newly discovered type III IFN, which plays a crucial role in antiviral immunity, has strong antiviral activity against PEDV proliferation in IPEC-J2 cells. In this study, we aimed to investigate the effect of PEDV nucleocapsid (N) protein on type III IFN-λ. We found that the N proteins of ten PEDV strains isolated between 2013 and 2017 from different local farms shared high nucleotide identities, while the N protein of the CV777 vaccine strain formed a monophyletic branch in the phylogenetic tree. The N protein of the epidemic strain could antagonize type III IFN, but not type I or type II IFN expression induced by polyinosinic-polycytidylic acid (poly(I:C)) in IPEC-J2 cells. Subsequently, we demonstrated that the inhibition of poly(I:C)- induced IFN-λ3 production by PEDV N protein was dependent on the blocking of nuclear factor-κB (NF-κB) nuclear translocation. These findings might help increase understanding of the pathogenesis of PEDV and its mechanisms for evading the host immune response.

Monoclinic wolframite Ni1-xCoxWO4(x = 0 and 0.15) nanosheets are synthesized successfully through chemical co-precipitation. The specific surface area increases appreciably with reduced pore radius when Co2+ions are incorporated into the NiWO4lattice. In comparison with NiWO4, the band gap of Ni0.85Co0.15WO4reduces with the electrical conductivity increased threefold. The electrochemical properties and the device performance of supercapacitors with Ni1-xCoxWO4as electrodes are characterized via the potentiostatic and galvanostatic cycle measurements, and electrochemical impedance spectroscopy (EIS). The Ni0.85Co0.15WO4electrode exhibits an obvious increase in specific capacitance, six-fold higher than that of NiWO4electrode at a current density of 0.5 A g−1. Ni0.85Co0.15WO4electrode also shows excellent rate performance with ~78% capacitive retention while the current density is enhanced fivefold. The possible mechanism for the improved electrical conductivity and capacitive performance due to the incorporation of Co2+to NiWO4lattice has been discussed.

Difficulties in emotion regulation are commonly reported among individuals with alcohol and drug addictions and contribute to the acquisition and maintenance of addictive behaviors. Alterations in neural processing of negative affective stimuli have further been demonstrated among individuals with addictions. However, it is unclear whether these alterations are a general feature of addictions or are a result of prolonged exposure to drugs of abuse. To test the hypothesis of altered negative affect processing independent of drug effects, this study assessed neural function among drug-naïve youth with a behavioral addiction—Internet gaming disorder (IGD). Fifty-six young adults (28 with IGD, 28 matched controls) participated in fMRI scanning during performance of a well-validated emotion regulation task. Between-group differences in neural activity during task performance were assessed using a whole-brain, mixed-effects ANOVA with correction for multiple comparisons at currently recommended thresholds (voxel-level p<0.001, pFWE<0.05). Compared to controls, youth with IGD exhibited significantly blunted neural responses within distributed subcortical and cortical regions including the striatum, insula, lateral prefrontal cortex and anterior cingulate in response to negative affective cues, as well as during emotion regulation. Independent component analysis (ICA) further identified between-group differences in engagement of a fronto-cingulo-parietal network, involving decreased engagement in IGD youth relative to controls. Study findings are largely consistent with those from prior neuroimaging studies in substance-use disorders, thus raising the possibility that neural processing of negative affect may be blunted across drug and behavioral addictions independent of acute or chronic drug effects.