69 research outputs found
A Two Step Synthesis Route of WC Nanopowders
Here, a novel molten salt route to synthesize ceramic WC nanopowders was presented. Compared to the traditional synthesis procedures, this method is relatively low cost involving two-step synthesis route. In the argon atmosphere at 650 oC, the powders were the mixed WC and W2C phases. These synthesized powders were transferred to a small crucible (30 mL) containing molten salt, which were put into a 500 mL crucible with some carbon powder in it as reducing atmosphere, followed by maintaining the reaction temperature at 1100 °C for 1 h. The phase purity and composition were characterized by the powder X-ray diffractometer (XRD). It was found that W2C was transformed thoroughly into WC, which indicated the successful synthesis of WC powders using this method. The mechanism of the reaction process in molten salt has been discussed finally. The thermogravimetric analysis indicated that the as-prepared samples showed good thermal stability and oxidation resistance in high temperature. The methodology reported in this work was fundamentally important, which may find potential industrial applications
Lipopolysaccharide-induced depression-like model in mice: meta-analysis and systematic evaluation
Depression is a complex and biologically heterogeneous disorder. Recent studies have shown that central nervous system (CNS) inflammation plays a key role in the development of depression. Lipopolysaccharide (LPS)-induced depression-like model in mice is commonly used to studying the mechanisms of inflammation-associated depression and the therapeutic effects of drugs. Numerous LPS-induced depression-like models in mice exist and differ widely in animal characteristics and methodological parameters. Here, we systematically reviewed studies on PubMed from January 2017 to July 2022 and performed cardinal of 170 studies and meta-analyses of 61 studies to support finding suitable animal models for future experimental studies on inflammation-associated depression. Mouse strains, LPS administration, and behavioral outcomes of these models have been assessed. In the meta-analysis, forced swimming test (FST) was used to evaluate the effect size of different mouse strains and LPS doses. The results revealed large effect sizes in ICR and Swiss mice, but less heterogeneity in C57BL/6 mice. For LPS intraperitoneal dose, the difference did not affect behavioral outcomes in C57BL/6 mice. However, in ICR mice, the most significant effect on behavioral outcomes was observed after the injection of 0.5 mg/kg LPS. Our results suggests that mice strains and LPS administration play a key role in the evaluation of behavioral outcomes in such models
Global urban environmental change drives adaptation in white clover.
Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale
Global urban environmental change drives adaptation in white clover
Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale
Optimal investment-reinsurance problems with common shock dependent risks under two kinds of premium principles
This paper considers the optimal investment-reinsurance strategy in a risk model with two dependent classes of insurance business under two kinds of premium principles, where the two claim number processes are correlated through a common shock component. Under the criterion of maximizing the expected exponential utility with the expected value premium principle and the variance premium principle, we use the stochastic optimal control theory to derive the optimal strategy and the value function for the compound Poisson risk model as well as for the Brownian motion diffusion risk model. In particular, we find that the optimal investment strategy on the risky asset is independent to the reinsurance strategy and the reinsurance strategy for the compound Poisson risk model are very different from those for the diffusion model under both two kinds of premium principles, but the investment strategies are the same in this two risk models. Finally, numerical examples are presented to show the impact of model parameters in the optimal strategies
MIR plasmonic liquid sensing in nano-metric space driven by capillary force
10.1088/1361-6463/ab2ea1JOURNAL OF PHYSICS D-APPLIED PHYSICS5239complete
capTEs enables locus-specific dissection of transcriptional outputs from reference and nonreference transposable elements
Abstract Transposable elements (TEs) serve as both insertional mutagens and regulatory elements in cells, and their aberrant activity is increasingly being revealed to contribute to diseases and cancers. However, measuring the transcriptional consequences of nonreference and young TEs at individual loci remains challenging with current methods, primarily due to technical limitations, including short read lengths generated and insufficient coverage in target regions. Here, we introduce a long-read targeted RNA sequencing method, Cas9-assisted profiling TE expression sequencing (capTEs), for quantitative analysis of transcriptional outputs for individual TEs, including transcribed nonreference insertions, noncanonical transcripts from various transcription patterns and their correlations with expression changes in related genes. This method selectively identified TE-containing transcripts and outputted data with up to 90% TE reads, maintaining a comparable data yield to whole-transcriptome sequencing. We applied capTEs to human cancer cells and found that internal and inserted Alu elements may employ distinct regulatory mechanisms to upregulate gene expression. We expect that capTEs will be a critical tool for advancing our understanding of the biological functions of individual TEs at the locus level, revealing their roles as both mutagens and regulators in biological and pathogenic processes
Relationship Management Capability and Service Innovation Performance: The Joint-Effect of Relationship Learning and Competitive Intensity
Relationship management capability is a significant factor in promoting a firm’s service innovation performance. Although there is a rich body of study on the role of relationship management capability in performance of firms, scant attention has been paid to the joint effect of relationship learning and competitive intensity. Drawing on the service innovation, network capability and relationship learning theories, this paper establishes a relevant conceptual model, and adopts a hierarchical regression analysis to examine the model with a data set of 298 firms from China. Results show that relationship management capability positively affects the service innovation performance of firms; however, relationship learning partially negatively moderates the relationship between relationship management capability and service innovation performance. The three-way interaction effects of relationship management capability, relationship learning and competitive intensity are partially significant. This paper extends the existing literature on service innovation, network capabilities and relational learning in a service-centered economy. The findings further clarify the process mechanism of the impact of relational management capabilities on enterprise service innovation performance, and should help enterprises utilize relational learning and competitive intensity to break through resource limitations rapidly. The paper offers some enlightenment on promoting service innovation
Relationship Management Capability and Service Innovation Performance: The Joint-Effect of Relationship Learning and Competitive Intensity
Relationship management capability is a significant factor in promoting a firm’s service innovation performance. Although there is a rich body of study on the role of relationship management capability in performance of firms, scant attention has been paid to the joint effect of relationship learning and competitive intensity. Drawing on the service innovation, network capability and relationship learning theories, this paper establishes a relevant conceptual model, and adopts a hierarchical regression analysis to examine the model with a data set of 298 firms from China. Results show that relationship management capability positively affects the service innovation performance of firms; however, relationship learning partially negatively moderates the relationship between relationship management capability and service innovation performance. The three-way interaction effects of relationship management capability, relationship learning and competitive intensity are partially significant. This paper extends the existing literature on service innovation, network capabilities and relational learning in a service-centered economy. The findings further clarify the process mechanism of the impact of relational management capabilities on enterprise service innovation performance, and should help enterprises utilize relational learning and competitive intensity to break through resource limitations rapidly. The paper offers some enlightenment on promoting service innovation
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