59 research outputs found

    Identifying and decoupling many-body interactions in spin ensembles in diamond

    Full text link
    We simulate the dynamics of varying density quasi-two-dimensional spin ensembles in solid-state systems, focusing on the nitrogen-vacancy centers in diamond. We consider the effects of various control sequences on the averaged dynamics of large ensembles of spins, under a realistic "spin-bath" environment. We reveal that spin locking is efficient for decoupling spins initialized along the driving axis, both from coherent dipolar interactions and from the external spin-bath environment, when the driving is two orders of magnitude stronger than the relevant coupling energies. Since the application of standard pulsed dynamical decoupling sequences leads to strong decoupling from the environment, while other specialized pulse sequences can decouple coherent dipolar interactions, such sequences can be used to identify the dominant interaction type. Moreover, a proper combination of pulsed decoupling sequences could lead to the suppression of both interaction types, allowing additional spin manipulations. Finally, we consider the effect of finite-width pulses on these control protocols and identify improved decoupling efficiency with increased pulse duration, resulting from the interplay of dephasing and coherent dynamics

    Hypericin Inhibit Alpha-Coronavirus Replication by Targeting 3CL Protease

    Get PDF
    The porcine epidemic diarrhea virus (PEDV) is an Alphacoronavirus (α-CoV) that causes high mortality in infected piglets, resulting in serious economic losses in the farming industry. Hypericin is a dianthrone compound that has been shown as an antiviral activity on several viruses. Here, we first evaluated the antiviral effect of hypericin in PEDV and found the viral replication and egression were significantly reduced with hypericin post-treatment. As hypericin has been shown in SARS-CoV-2 that it is bound to viral 3CLpro, we thus established a molecular docking between hypericin and PEDV 3CLpro using different software and found hypericin bound to 3CLpro through two pockets. These binding pockets were further verified by another docking between hypericin and PEDV 3CLpro pocket mutants, and the fluorescence resonance energy transfer (FRET) assay confirmed that hypericin inhibits the PEDV 3CLpro activity. Moreover, the alignments of α-CoV 3CLpro sequences or crystal structure revealed that the pockets mediating hypericin and PEDV 3CLpro binding were highly conserved, especially in transmissible gastroenteritis virus (TGEV). We then validated the anti-TGEV effect of hypericin through viral replication and egression. Overall, our results push forward that hypericin was for the first time shown to have an inhibitory effect on PEDV and TGEV by targeting 3CLpro, and it deserves further attention as not only a pan-anti-α-CoV compound but potentially also as a compound of other coronaviral infections

    Assessing efficiency in sustainable allocation of agricultural scientific and technological talent: a spatial-temporal analysis in China

    Get PDF
    Efficient allocation of agricultural scientific and technological talents (ASTTs) is crucial for agricultural innovation and economic development. This study aims to systematically evaluate ASTTs’ allocation efficiency in provincial agricultural research institutions in China, aiding decision-making for local governments and research bodies. Utilizing data from 2009 to 2019 across 31 provinces, an output-oriented data envelopment analysis model measures ASTTs’ allocation efficiency and analyzes its trends, regional differences, and spatial characteristics. Results show: (1) Provincial ASTTs’ mean comprehensive technical efficiency (CTE) in China was 0.786, with room for improvement. (2) Enhanced CTE was driven by scale efficiency improvements, while pure technical efficiency declined, indicating a need for better management systems and technology applications. (3) Disparities in ASTTs’ allocation efficiency among provinces decreased, with higher efficiencies in the East and Central-Southern China regions. At the provincial level, areas like Jiangsu, Shandong, Henan, and Sichuan demonstrated relatively high ASTTs allocation efficiencies. (4) Spatial agglomeration of ASTTs’ allocation efficiency was localized in a few major agricultural provinces without a significant overall effect. These findings advocate for further optimization of ASTTs’ regional layout and management mechanisms in China

    Research Progress of Tyramine Formation and Control Methods in Fermented Meat Products

    Get PDF
    Fermented meat products is the meat products with special flavor, color, texture and longer shelf life formed by a series of changes under natural or artificially controlled conditions by the action of microorganisms or enzymes. Fermented meat products is popular with consumers, but they are rich in protein and have a great potential for high levels of biogenic amines. Among them, histamine and tyramine are the most toxic. Consumption of tyramine-rich foods might cause headache, hypertension and other adverse reactions. Therefore, it is extremely necessary to control the tyramine content in fermented meat products. In this paper, the formation pathways, control methods and effects of tyramine in fermented meat products are reviewed. Among them, the main formation pathway is the decarboxylation of tyrosine by the action of decarboxylase, in addition to the existence of chemical pathways related to lipid oxidation products, while the more effective control methods are the addition of auxiliaries and the inoculation of fermentation agents. This paper aims to provid a theoretical support for reducing the tyramine content in fermented meat products and improving the safety of fermented meat products

    Ethyl methanesulfonate mutant library construction in Neopyropia yezoensis to provide germplasm resources for next-generation genome-selection breeding

    Get PDF
    With the development of the laver industry, germplasm depression has become a serious issue, and current cultivars cannot adapt to different aquaculture regions. In order to increasing the genetic diversity and developing more germplasm sources, it is urgent and reasonable to construct a mutant library with more new germplasms. In this research, a mutant library was constructed by ethyl methanesulfonate (EMS)-mutagenized archeospores, and the most optimal treatment procedure was determined by performing different mutagen concentrations (2.25%) and treatment times (30 min). A total of 1860 haploid thalli were produced as the M1 mutant population and further cultured into conchocelis clones for the reservation of germplasm resources. Among these, 667 individual thalli were evaluated for their phenotypic traits, including thallus length, thallus width, length/width, thallus shape, photosynthesis ability, thallus color, thallus margin, and specific growth speed. The mutation frequency of the length/width ratio was 17.39%, Fv/Fm and NPQ were 21.84% and 29.35%, respectively, and SGR was 13.59%. The mutation frequency of thallus color was 0.91%. This work may not only provide a basic practical reference guide for EMS-based mutant library construction for other seaweeds but, more importantly, also serve as a valuable resource for functional genomics research and laver breeding

    The histone H3K9M mutation synergizes with H3K14 ubiquitylation to selectively sequester histone H3K9 methyltransferase Clr4 at heterochromatin

    Get PDF
    International audienceOncogenic histone lysine-to-methionine mutations block the methylation of their corresponding lysine residues on wild-type histones. One attractive model is that these mutations sequester histone methyltransferases, but genome-wide studies show that mutant histones and histone methyltransferases often do not colocalize. Using chromatin immunoprecipitation sequencing (ChIP-seq), here, we show that, in fission yeast, even though H3K9M-containing nucleosomes are broadly distributed across the genome, the histone H3K9 methyltransferase Clr4 is mainly sequestered at pericentric repeats. This selective sequestration of Clr4 depends not only on H3K9M but also on H3K14 ubiquitylation (H3K14ub), a modification deposited by a Clr4-associated E3 ubiquitin ligase complex. In vitro, H3K14ub synergizes with H3K9M to interact with Clr4 and potentiates the inhibitory effects of H3K9M on Clr4 enzymatic activity. Moreover, binding kinetics show that H3K14ub overcomes the Clr4 aversion to H3K9M and reduces its dissociation. The selective sequestration model reconciles previous discrepancies and demonstrates the importance of protein-interaction kinetics in regulating biological processes

    Rabies virus pseudotyped with CVS-N2C glycoprotein as a powerful tool for retrograde neuronal network tracing

    Get PDF
    Abstract Background: Efficient viral vectors for mapping and manipulating long projection neuronal circuits are crucial in brain structural and functional studies. The glycoprotein gene-deleted SAD strain rabies virus pseudotyped with the N2C glycoprotein (SAD-RV(ΔG)-N2C(G)) shows high neuro-tropism in cell culture, but its in vivo retrograde infection efficiency and neuro-tropism have not been systematically characterized. Methods: SAD-RV(ΔG)-N2C(G) and two other broadly used retrograde tracers, SAD-RV(ΔG)-B19(G) and rAAV2-retro were respectively injected into the VTA or DG in C57BL/6 mice. The neuron numbers labeled across the whole brain regions were counted and analyzed by measuring the retrograde infection efficiencies and tropisms of these viral tools. The labeled neural types were analyzed using fluorescence immunohistochemistry or GAD67-GFP mice. Result: We found that SAD-RV (ΔG)-N2C (G) enhanced the infection efficiency of long-projecting neurons by ~ 10 times but with very similar neuro-tropism, compared with SAD-RV (ΔG)-B19(G). On the other hand, SAD-RV(ΔG)-N2C(G) showed comparable infection efficiency with rAAV2-retro, but had a more restricted diffusion range, and broader tropism to different types and regions of long-projecting neuronal populations. Conclusions: These results demonstrate that SAD-RV(ΔG)-N2C(G) can serve as an effective retrograde vector for studying neuronal circuits. Key words:Viral vector, N2C Glycoprotein, Neuronal circuits, Retrograde tracin

    Research on the Upgrading Path of Emerging Industry Innovation Service Network

    No full text
    Innovation service network is the inevitable result of the collaborative cooperation of innovation service subjects, and also an important strategic resource for innovation activities in emerging industries. The research of innovation service network has important decision reference value for the promotion of collaborative service capability for the innovation demand of emerging industries. By analyzing the evolution process and law of innovation service network in emerging industries, improving the main line around the ability of collaborative service, combining the evolution stage of innovation service network, the complexity of innovation demand and the integration of service resources, this paper focuses on designing the upgrade path of innovation service network based on key nodes, the path of innovation service network upgrade based on service chain integration, and the upgrade path of innovation service network based on core network coordination, in order to optimize the structure of innovation service network of emerging industries and improve its ability of collaborative service provides theoretical guidance, which is of great practical significance to support the innovation and development of emerging industries

    The Evolution of E-Commerce Service Ecosystem

    Get PDF
    On the basis of defining e-commerce service ecosystem (ECSEM), we elaborated its population constitution and structure, drew on the theory of industrial ecosystem and the development course of e-commerce in China to discuss the evolutionary path and process, and concretely analyze the evolutionary process and characteristics of crucial components included in this ecosystem, such as all kinds of service providers, competitors, industrial rule and standard systems, etc. In the end, a case of Alibaba’s ECSEM and its evolution was analyzed to testify our study. This paper aimed to build the basic theory of ECSEM and reveal its evolutionary process and laws, so as to provide reference for the construction and development of ECSEM

    Pharmaceutical Dispersion Techniques for Dissolution and Bioavailability Enhancement of Poorly Water-Soluble Drugs

    No full text
    Over the past decades, a large number of drugs as well as drug candidates with poor dissolution characteristics have been witnessed, which invokes great interest in enabling formulation of these active ingredients. Poorly water-soluble drugs, especially biopharmaceutical classification system (BCS) II ones, are preferably designed as oral dosage forms if the dissolution limit can be broken through. Minimizing a drug’s size is an effective means to increase its dissolution and hence the bioavailability, which can be achieved by specialized dispersion techniques. This article reviews the most commonly used dispersion techniques for pharmaceutical processing that can practically enhance the dissolution and bioavailability of poorly water-soluble drugs. Major interests focus on solid dispersion, lipid-based dispersion (nanoencapsulation), and liquisolid dispersion (drug solubilized in a non-volatile solvent and dispersed in suitable solid excipients for tableting or capsulizing), covering the formulation development, preparative technique and potential applications for oral drug delivery. Otherwise, some other techniques that can increase the dispersibility of a drug such as co-precipitation, concomitant crystallization and inclusion complexation are also discussed. Various dispersion techniques provide a productive platform for addressing the formulation challenge of poorly water-soluble drugs. Solid dispersion and liquisolid dispersion are most likely to be successful in developing oral dosage forms. Lipid-based dispersion represents a promising approach to surmounting the bioavailability of low-permeable drugs, though the technique needs to traverse the obstacle from liquid to solid transformation. Novel dispersion techniques are highly encouraged to develop for formulation of poorly water-soluble drugs
    • …
    corecore