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Heterostructure or doping engineering on Mo2C by coupling with transition metal nanoparticles/atoms can optimize catalytic activities for oxygen evolution reaction (OER). However, the intrinsic catalytic activity of Mo2C is not fully stimulated at the atomic level, which is challenging. Herein, an adjacent‐confined pyrolysis strategy to manipulate the intrinsic electronic structure of Mo2C directly is reported. During the nucleation and growth of Mo2C, the replacement of Mo atoms by adjacent Ni atoms induces the generation of high‐density phase boundaries (PBs) with alternating face‐centered cubic (fcc) and hexagonal close‐packed (hcp) hetero‐phase. The lattice deformity in PBs affords an ultrahigh density of active sites, endowing Mo2C nanosheets with excellent OER activity and superior stability. Theoretical calculations reveal that introduced Ni atoms activate the adjacent Mo sites and optimize the thermodynamic reaction energetics for enhanced OER activity. The work offers a general adjacent‐confined pyrolysis strategy to achieve PBs‐controlling in Mo2C nanosheets for catalytic application and beyond. [ABSTRACT FROM AUTHOR]

Introduction: Prior studies suggested that neuromuscular factors might be involved in the pathogenesis of adolescent idiopathic scoliosis (AIS). The neuromuscular junction (NMJ) is the important pivot where the nervous system interacts with muscle fibers, but it has not been well characterized in the paraspinal muscles of AIS. This study aims to perform the quantitative morphological analysis of NMJs from paraspinal muscles of AIS. Methods: AIS patients who received surgery in our center were prospectively enrolled. Meanwhile, age‐matched congenital scoliosis (CS) and non‐scoliosis patients were also included as controls. Fresh samples of paraspinal muscles were harvested intraoperatively. NMJs were immunolabeled using different antibodies to reveal pre‐synaptic neuronal architecture and post‐synaptic motor endplates. A confocal microscope was used to acquire z‐stack projections of NMJs images. Then, NMJs images were analyzed on maximum intensity projections using ImageJ software. The morphology of NMJs was quantitatively measured by a standardized 'NMJ‐morph' workflow. A total of 21 variables were measured and compared between different groups. Results: A total of 15 AIS patients, 10 CS patients and 5 normal controls were enrolled initially. For AIS group, NMJs in the convex side of paraspinal muscles demonstrated obviously decreased overlap when compared with the concave side (34.27% ± 8.09% vs. 48.11% ± 10.31%, p = 0.0036). However, no variables showed statistical difference between both sides of paraspinal muscles in CS patients. In contrast with non‐scoliosis controls, both sides of paraspinal muscles in AIS patients demonstrated significantly smaller muscle bundle diameters. Conclusions: This study first elucidated the morphological features of NMJs from paraspinal muscles of AIS patients. The NMJs in the convex side showed smaller overlap for AIS patients, but no difference was found in CS. This proved further evidence that neuromuscular factors might contribute to the mechanisms of AIS and could be considered as a novel potential therapeutic target for the treatment of progressive AIS. [ABSTRACT FROM AUTHOR]

Dynamic fault tree (DFT) is designed to conduct risk assessment studies of complex systems. With the development of intelligent and network technology, risk assessment technology faces a leap forward development. The requirements for improving system safety are being recognized. On the one hand, research on DFT is exploring the integration with different methods. On the other hand, DFT method becomes more intelligent. The purpose of this paper is to identify the feasibility and effectiveness of different integration frameworks. To achieve this goal, a suitable review process is proposed. This paper comprehensively reviews and proposes future perspective the research status of intellectualization in DFT, and focuses on the different types of integration framework of DFT, modeling technology and algorithm optimization, and the support of computer‐aided analysis. Theoretical contributions, frameworks features, and the development process of computer intelligent analysis in the scientific and technical literature are carefully reviewed. Finally, the challenges in future research are summarized to promote the development of intelligent evaluation. [ABSTRACT FROM AUTHOR]

A series of saccharin derivatives containing 2‐ aminothiazole scaffold were designed, synthesized, and characterized by 1H NMR, 13C NMR, and HRMS. The fungicidal activities of these novel compounds against Botrytis cinerea, Curvularia lunata, and Rhizoctonia solani were evaluated. The results indicated that N‐(4‐((1,1‐dioxido‐3‐oxobenzo[d]isothiazol‐2(3H)‐yl) methyl) thiazol‐2‐yl) acrylamide (HST3) displayed potential fungicidal activities against C. lunata, and R. solani with IC50 values of 15.0 mg/L and 12.9 mg/L respectively, which possessed higher fungicidal activity than commercial products hymexazol and amicarthiazol. Moreover, N‐(4‐((1,1‐dioxido‐3‐oxobenzo[d]isothiazol‐2(3H)‐yl) methyl) thiazol‐2‐yl)‐4‐methoxybenzamide (HST9) possessed an IC50 value of 1.1 mg/L against B. cinerea, superior to hymexazol, amicarthiazol, and carboxin. Besides, the superficial structure‐activity relationship was discussed. Furthermore, molecular docking result suggest that SDH enzyme might be one of the action targets of title compounds. [ABSTRACT FROM AUTHOR]

To date, only few a types of nanomedicines have been made available for clinical use even in the most common liposomal delivery systems, due to significant constraints, including poor targeting of specific cells, hindered penetration, and accelerated clearance. Various intricate designs have been generated and show improvements, while also bringing new problems. Biological cells, possessing advantages like low immunogenicity, long circulation time, receptors integration, and innate targeting capability. Herein, liposomes are innovatively functionalized with a stem cell membrane through a facile approach. The biomimetic vesicles achieve controlled release, exhibit better stability, longer circulation time, and targeted delivery. Loading with curcumin leads to enhanced survival rate of ischemic stroke mice with a single injection (from ≈30% to over 90%). The versatility of the method is verified by differently charged liposomes modification and erythrocyte membrane derived vesicles preparation. Overall, the cell membrane derived biomimetic vesicles achieve targeted delivery and versatility prepared by a facile approach, as well as effortless preparation. [ABSTRACT FROM AUTHOR]

Coronavirus disease 2019 (COVID‐19) has spread around the world and requires effective control measures. Like the human‐to‐human transmission of the severe acute respiratory syndrome‐coronavirus 2 (SARS‐CoV‐2), the distribution of COVID‐19 was driven by population flow and required emergency response measures to slow down its spread and degrade the epidemic risk. The local epidemic risk of COVID‐19 is a combination of emergency response measures and population flow. Because of the spatial heterogeneity, the different impacts of coupled emergency responses and population flow on the COVID‐19 epidemic during the outbreak period and a control period are unclear. We examined and compared the impact of emergency response measures and population flow on China's epidemic risk after the Wuhan lockdown during the outbreak period and a control period. We found that the population flow out of Wuhan had a long‐term impact on the epidemic's spread. In the outbreak period, a large population flow out of Wuhan led to nationwide migration mobility, which directly increased the epidemic in each province. Meanwhile, quick emergency responses mitigated the spread. Although low population flow to provinces far from Hubei delayed the outbreak in those provinces, relatively delayed emergency response increased the epidemic in the control period. Consequently, due to the strong transmission ability of the SARS‐CoV‐2 virus, no region correctly estimated the epidemic, and the relaxed emergency response raised the epidemic risks in the context of the outbreak. Key Points: Population outflow from Wuhan had a long‐term impact on the spread of COVID‐19Areas with low population inflow lacked awareness of prevention, started emergency response later, and failed to prevent the COVID‐19 caused by population mobilityThe degree to which population mobility and emergency measures affected the development of the epidemic exists spatial heterogeneity in China [ABSTRACT FROM AUTHOR]

A series of novel 2‐aryl‐thiazole derivatives containing saccharin were designed and synthesized by a facile method, and their structures were characterized by 1H NMR, 13C NMR and HMRS. Biological tests indicated that the parts of 2‐aryl‐thiazole derivatives possess potent fungicidal activities against Sclerotinia sclerotiorum, Botrytis cinerea, and Alternaria altanata. Especially, N‐((2‐(4‐chlorophenyl)thiazol‐4‐yl)methyl)‐4‐(1,1‐dioxido‐3‐oxobenzo[d]isothia‐zol‐2(3H)‐yl)butanamide (7 p) displays inhibition rates of 49.2 % and 41.9 % at a concentration of 10 mg/L against S. sclerotiorum and B. cinerea respectively, while 2‐(1,1‐dioxido‐3‐oxobenzo[d]isothiazol‐2(3H)‐yl)‐N‐((2‐(4‐methoxyphenyl)thiazol‐4‐yl)methyl)acetamide (7 f) shows an inhibition rate of 53.3 % at a concentration of 10 mg/L against A. altanata. Furthermore, the structure‐activity relationship was discussed. It suggested that the 2‐aryl‐thiazole group can be considered as a precursor structure for further design of fungicides. [ABSTRACT FROM AUTHOR]

By developing a diastereoselective reaction of cyclopropene carboxylic acids with α,β‐unsaturated 2‐acyl imidazoles, we reported here a Michael‐type trapping of transient carboxylic oxonium ylides. This transformation provides a direct approach for the construction of valuable γ‐butenolide derivatives in good yields (60–99%) with high diastereoselectivities (up to >95:5 dr) under mild reaction conditions. [ABSTRACT FROM AUTHOR]

A simple two‐step access to 1,1,1‐trifluoro‐2,5‐diketones and 2‐(trifluoromethyl)furans was developed through magnesium‐promoted reductive trifluoroacetylation of benzalacetones and acid‐facilitated deacetalization. Two types of trifluoromethylated compounds were selectively synthesized from easily prepared aromatic conjugated enones and ethyl trifluoroacetate by control of reaction conditions in moderate to high yields with wide substrate tolerance. [ABSTRACT FROM AUTHOR]

Tartary buckwheat (Fagopyrum tataricum) not only provides a supplement to primary grain crops in China but also has high medicinal value, by virtue of its rich content of flavonoids possessing antioxidant, anti‐inflammatory, and anticancer properties. Light is an important environmental factor that can regulate the synthesis of plant secondary metabolites. In this study, we treated tartary buckwheat seedlings with different wavelengths of light and found that red and blue light could increase the content of flavonoids and the expression of genes involved in flavonoid synthesis pathways. Through coexpression analysis, we identified a new MYB transcription factor (FtMYB116) that can be induced by red and blue light. Yeast one‐hybrid assays and an electrophoretic mobility shift assay showed that FtMYB116 binds directly to the promoter region of flavonoid‐3′‐hydroxylase (F3'H), and a transient luciferase activity assay indicated that FtMYB116 can induce F3'H expression. After transforming FtMYB116 into the hairy roots of tartary buckwheat, we observed significant increases in the content of rutin and quercetin. Collectively, our results indicate that red and blue light promote an increase in flavonoid content in tartary buckwheat seedlings; we also identified a new MYB transcription factor, FtMYB116, that promotes the accumulation of rutin via direct activation of F3′H expression. We revealed that red and blue light promote flavonoid production and the expression of genes involved in flavonoid synthesis pathways in tartary buckwheat. We also identified a new MYB transcription factor, FtMYB116, that promotes rutin accumulation via direct activation of the expression of F3′H. [ABSTRACT FROM AUTHOR]

Thermally stimulated depolarization current (TSDC) experiments were carried out to investigate the effect of polarization temperature on different relaxation processes in barium strontium titanate glass‐ceramics. It was found that all the TSDC curves are composed of four relaxation peaks. From the characteristics of peak temperature and peak current intensity with various polarization temperatures, the origin of these four peaks are identified as from defect dipole orientation, charge carrier detrapping, in‐crystal oxygen vacancy migration, and trans‐interface oxygen vacancy migration respectively. In addition, both the dipole concentration and trap density for the glass‐ceramic samples were estimated. [ABSTRACT FROM AUTHOR]

An approach to trifluoroacetylation of aromatic conjugated esters successfully led to the efficient and selective introduction of trifluoroacetyl group to the electron‐deficient β‐ or δ‐carbon atom of ester under mild reaction conditions by magnesium‐promoted reduction, followed by deacetalization with trifluoroacetic acid in moderate to good yields. A variety of fluorinated keto esters derived from ethyl cinnamates and β, γ‐ or γ‐, δ‐unsaturated fluorinated keto esters from aromatic dienoesters with a longer conjugation system were synthesized through this simple methodology utilizing ethyl trifluoroacetate as a fluorine‐containing carbon source. Simple and selective introduction of a trifluoroacetyl group into the electron‐deficient β‐ or δ‐carbon atom of aromatic conjugated esters was achieved by use of ethyl trifluoroacetate in good yields through magnesium‐promoted trifluoroacetylation, followed by deacetalization with trifluoroacetic acid. [ABSTRACT FROM AUTHOR]

Previously, we found a 199 bp element which inserted into the promoter of PdCYP51B gene in Penicillium digitatum, was associated with the overexpression of this gene and DMI fungicides resistance. However, the mechanism how this 199 bp element upregulate the expression of downstream gene was completely unknown. In the current study, we confirmed that this 199 bp element was a MITE-like element, designated as PdMLE1. blast searching and Southern blot showed that this 199 bp element was unique to P. digitatum. Genome-wide localization of PdMLE1 showed that it preferentially inserted into A + T rich regions, and several copies localized at the coding or regulation regions of genes were found. Penicillium digitatum mutant harbouring the PdMLE1 fused GFP gene showed the strong green fluorescence, indicating the powerful promoter activity of PdMLE1. By promoter deletion method, we identified a 20 bp core sequence in PdMLE1 which was associated with its promoter activity. In addition, we also limited the core element of PdCYP51B promoter to a 368 bp region. Collectively, we proposed a model that PdMLE1 acted as a powerful promoter and most likely recruited the transcription factor(s), therefore led to the overexpression of PdCYP51B gene and conferred P. digitatum with DMI resistance. This is the first regulation model of transposon resulted fungicide resistance proved in plant pathogens. [ABSTRACT FROM AUTHOR]

Real‐time effective traffic flow big data prediction network has important application significance. Over the past few years, traffic flow data have been exploding and we have entered the big data era. The key challenge of traffic flow prediction network is how to construct an adaptive model relying on historical data. Existing big data‐driven traffic flow prediction networking approaches mainly use shallow learning, and there are unsatisfying for many realistic applications, which inspire us to rethink the traffic flow big data prediction problem with deep learning. In this paper, we propose a novel prediction approach based on machine learning. In addition to the minimum prediction error as the goal, we present the long short‐term memory model, which is a typical machine learning algorithm with deep learning network. This method is applied into the real‐world traffic big data from performance measurement system. Experimental results show that the proposed machine learning algorithm has more applicability and higher performance, compared with shallow machine learning prediction network. [ABSTRACT FROM AUTHOR]

Unsatisfactory post‐stroke recovery has long been a negative factor in the prognosis of ischemic stroke due to the lack of pharmacological treatments. Mesenchymal stem cells (MSCs)‐based therapy has recently emerged as a promising strategy redefining stroke treatment; however, its effectiveness has been largely restricted by insufficient therapeutic gene expression and inadequate cell numbers in the ischemic cerebrum. Herein, a non‐viral and magnetic field‐independent gene transfection approach is reported, using magnetosome‐like ferrimagnetic iron oxide nanochains (MFIONs), to genetically engineer MSCs for highly efficient post‐stroke recovery. The 1D MFIONs show efficient cellular uptake by MSCs, which results in highly efficient genetic engineering of MSCs to overexpress brain‐derived neurotrophic factor for treating ischemic cerebrum. Moreover, the internalized MFIONs promote the homing of MSCs to the ischemic cerebrum by upregulating CXCR4. Consequently, a pronounced recovery from ischemic stroke is achieved using MFION‐engineered MSCs in a mouse model. [ABSTRACT FROM AUTHOR]

The synthesis of partially fluorinated organic compounds is one of the most attractive topics in synthetic organic chemistry, and especially in medicinal chemistry, in recent years. A regioselective and direct introduction of a trifluoroacetyl group into electron‐deficient carbon atoms of aromatic conjugated esters is described herein. The reaction proceeds in good yields through a magnesium‐promoted reduction in the presence of ethyl trifluoroacetate as a fluorine‐containing carbon source. More information can be found in the Communication by Hirofumi Maekawa et al. on page 344 in Issue 3, 2019 (DOI: 10.1002/ajoc.201800741). [ABSTRACT FROM AUTHOR]

The Mg-promoted reductive silylation of 2- and 4-vinylpyridines gives rise to the formation of the corresponding β-mono-silylated compounds. [ABSTRACT FROM AUTHOR]

Byproducts of type (IV) are obtained in most cases in less than 20% yield. [ABSTRACT FROM AUTHOR]

As part of a fully integrated and comprehensive strategy to discover novel antibacterial agents, NMR- and mass spectrometry-based affinity selection screens were performed to identify compounds that bind to protein targets uniquely found in bacteria and encoded by genes essential for microbial viability. A biphenyl acid lead series emerged from an NMR-based screen with the Haemophilus influenzae protein HI0065, a member of a family of probable ATP-binding proteins found exclusively in eubacteria. The structure-activity relationships developed around the NMR-derived biphenyl acid lead were consistent with on-target antibacterial activity as the Staphylococcus aureus antibacterial activity of the series correlated extremely well with binding affinity to HI0065, while the correlation of binding affinity with B-cell cytotoxicity was relatively poor. Although further studies are needed to conclusively establish the mode of action of the biphenyl series, these compounds represent novel leads that can serve as the basis for the development of novel antibacterial agents that appear to work via an unprecedented mechanism of action. Overall, these results support the genomics-driven hypothesis that targeting bacterial essential gene products that are not present in eukaryotic cells can identify novel antibacterial agents.

The D-Ala-D-Ala adding enzyme (MurF) from Streptococcus pneumoniae catalyzes the ATP-dependent formation of the UDP-MurNAc-pentapeptide, a critical component of the bacterial cell wall. MurF is a potential target for antibacterial design because it is unique to bacteria and performs an essential non-redundant function in the bacterial cell. The recent discovery and subsequent cocrystal structure determination of MurF in complex with a new class of inhibitors served as a catalyst to begin a medicinal chemistry program aimed at improving their potency. We report here a multidisciplinary approach to this effort that allowed for rapid generation of cocrystal structures, thereby providing the crystallographic information critical for driving the inhibitor optimization process. This effort resulted in the discovery of low-nanomolar inhibitors of this bacterial enzyme.