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Ammonia, being a carbon-free fuel, is garnering increasing attention in the combustion community. However, its application is still impeded by its limited stability range and significantly NOx emissions. This study delves into the impact of primary and overall equivalence ratios (ϕ pri and ϕ ovr) on emissions production in ammonia–hydrogen co-firing flames, utilizing a two-stage swirling model gas turbine combustor. The emissions concentration is measured using Fourier Transform Infrared Spectroscopy (FTIR). The physical and chemical processes influencing emissions production are comprehensively analyzed through a combination of Large Eddy Simulation (LES) and Flamelet-Generated Manifold (FGM) method. The reliability of the simulation is validated by the experimental data, showing a good capability in predicting the combustion. Results indicate that the two-stage combustion strategy exhibits significantly controlling effects on NOx and unburned NH 3 emission. The NO emission exhibits a non-monotonic variation with ϕ pri , reaching its lowest value at ϕ pri ≈ 1.2. Further analysis shows that ϕ pri plays a crucial role in determining the temperature and OH concentration in the primary combustion zone, thereby influencing NOx production in this area. When the primary zone is operated at lean condition, the reduction on NO in secondary zone is primarily attributed to dilution effect by the secondary air. In contrast, when ϕ pri > 1, the concentrations of the main emissions in secondary zone are dominated by chemical effects. In this scenario, unburned NH 3 and H 2 from the primary zone are consumed, resulting in a substantial production of NO in the secondary combustion zone. Additionally, with an increase in ϕ pri , the secondary NO production also increases. The ϕ ovr exhibits two considerable effects. On one hand, an increase in ϕ ovr results in a higher local equivalence ratio in the secondary zone, thereby promoting local NOx production. Simultaneously, the elevated flame temperature enhances the consumption of N 2 O. On the other hand, the rise in ϕ ovr results in a reduction in vortex scale and residence time in the secondary combustion zone, leading to a decrease in local NO production. • The NOx mitigation of NH 3 /H 2 /air co-firing flames have been achieved through the secondary staged air. • The proposed LES-FGM method was validated adequate predicting the flow field and emission characters. • The impact of primary and overall equivalence ratio on emissions have been revealed in-depth. • The optimal operating condition for emission control in the current combustor has been proposed. [ABSTRACT FROM AUTHOR]

To explore the methylation status, function, and underlying mechanism of the imprinted gene Neuronatin (NNAT) in hepatocellular carcinoma (HCC) progression. Immunohistochemistry (IHC) was performed to evaluate the expression of NNAT in HCC samples. Bisulfite genomic sequencing PCR (BSP) was applied to examine the methylation status of the NNAT promoter. In addition, colony formation, 5-Ethynyl-20-deoxyuridine (EdU) assays and subcutaneous xenograft nude models were used to explore the roles of NNAT in HCC cell proliferation. Furthermore, RNA-seq and phospho-specific protein microarray assays were conducted to illustrate the underlying mechanism by which NNAT regulates HCC progression. NNAT was obviously downregulated in HCC tissues, and its expression level was closely associated with tumor growth and patient prognosis. The downregulation of NNAT in HCC was induced by hypermethylation of CpG islands in the promoter region, and hypermethylation was correlated with overall survival of HCC. Moreover, the enforced expression of NNAT significantly inhibited HCC cell proliferation in vitro and in vivo. Transcriptome analysis showed that the alteration of NNAT expression was mainly related to dysregulation of the PI3K-Akt signaling pathway. Finally, phospho-specific antibody microarray detection further revealed that overexpressed NNAT can increase the phosphorylation levels of LKB1, Met, and elF4E and decrease the phosphorylation levels of PTEN, which are all involved in the PI3K-Akt signaling pathway. Our research provides new insights into the epigenetic regulation of imprinted genes in tumorigenesis and implies that the imprinted gene NNAT may act as a prognostic biomarker and tumor suppressor in HCC. [ABSTRACT FROM AUTHOR]

Cancer immunotherapy is a powerful weapon in the fight against cancers. Cyclic dinucleotides (CDNs) have demonstrated the great potential by evoking the immune system to fight cancers. There are still a lot of unmet needs for highly active CDNs in clinical applications due to low cell permeation and serum stability. Here we reported S -acylthioalkyl ester (SATE)-based prodrugs of deoxyribose cyclic dinucleotides (dCDNs) with three different types of internucleotide linkages (3′,3′: 11a ; 2′,3′: 11b ; 2′,2′: 11c). The parent dCDNs could be efficiently released from SATE-dCDNs by cellular esterases. Compared to 2′,3′-cGAMP and ADU-S100, 11a exhibited much higher potency of activating STING pathway and higher serum stability. In a CT26-Luc tumor-bearing animal model, 11a showed the efficient antitumor activity in eliminating the established tumor and induced significant increase of mRNA expression of IFN-β and other related inflammatory cytokines. Hence, SATE-dCDN prodrugs demonstrated their benefits in promoting cell penetration, improving serum stability, and thus enhancing bioactivity, suggesting their potential application as immunotherapy in a variety of malignancies. [Display omitted] • Three SATE-dCDN prodrugs (11a , 11b , and 11c) were designed as STING agonists. • 11a was identified as a highly potent STING agonist with an EC 50 value of 5.2 nM. • 11a could suppress tumor growth in the CT26-Luc tumor-bearing mouse model. • 11a and 11b led to significant cytokine induction. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study a nonlinear wave equation with anisotropy and a source term. Under some appropriate assumptions on the parameters, and with certain initial data, we obtain several results on the existence of local solutions and the blow up of solutions in finite time. [Copyright &y& Elsevier]

Abstract: In this paper, we consider a strongly damped wave equation with fractional damping on part of its boundary and also with an internal source. Under some appropriate assumptions on the parameters, and with certain initial data, a blow-up result with positive initial energy is established. [Copyright &y& Elsevier]

Abstract: In this paper, we consider a Cauchy problem for a nonlinear viscoelastic equation with nonlinear damping and source terms. Under suitable assumptions on the initial data and the relaxation function, we establish a finite-time blow-up result and a global existence result. [Copyright &y& Elsevier]

Abstract: In this paper, we consider a nonlinear viscoelastic wave equation with nonlinear boundary damping and source terms. Under some appropriate assumptions on the relaxation function and with certain initial data, the global existence of solutions and a general decay for the energy have been established. [Copyright &y& Elsevier]