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In solid propellants, combustion catalysts play a crucial role. Here, we introduce a convenient method for the self-assembly of UIO-66 (Mn) in the presence of water, leading to the preparation of Mn/C aerogels. The aerogels were successfully utilized in the thermocatalytic decomposition of ammonium perchlorate (AP). The results indicate that the incorporation of 2% mass fraction of Mn/C aerogels enhances the peak temperature of AP decomposition by approximately 87.5°C. Mn/C aerogels demonstrate excellent catalytic performance. In combination with kinetics, we propose a thermal catalytic mechanism., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhao, Liu, Wang, Fu and Deng.)

Timely flowering is a determinative trait for many economically valuable species in the Dendrobium genus of the Orchidaceae family, some of which are used for ornamental and medicinal purposes. D. nobile , a representative species of nobile-type Dendrobium , normally flowers in spring after exposure to sufficient low temperatures in winter. However, flowering can be stopped or disrupted by the untimely application of high temperatures. Little is known about the regulation and the mechanisms behind this switch. In this study, we report two isoforms from the KFK09_017173 locus of the D. nobile genome, named DnFCAγ and DnFCAβ , respectively, that cooperatively regulate flowering in D. nobile . These two isoforms are generated by alternative 3' polyadenylation of DnFCA (FLOWERING CONTROL LOCUS C in D. nobile) pre-mRNA and contain a distinct 3'-terminus. Both can partially rescue late flowering in the Arabidopsis fca - 1 mutant, while in wild-type Arabidopsis , they tend to delay the flowering time. When introduced into the detached axillary buds or young seedlings of D. nobile , both were able to induce the transcription of DnAGL19 ( AGAMOUS LIKE 19 in D. nobile) in seedlings, whereas only DnFCAγ was able to suppress the transcription of DnAPL1 (AP1-LIKE 1 in D. nobile) in axillary buds. Furthermore, the time-course change of DnFCAγ accumulation was opposite to that of DnAPL1 in axillary buds, which was remarkable under low temperatures and within a short time after the application of high temperatures, supporting the suggestion that the expression of DnAPL1 can be inhibited by a high accumulation of DnFCAγ in floral buds. In leaves, the accumulation of DnFCAβ was in accordance with that of DnAGL19 and DnFT ( FLOWERING LOCUS T in D. nobile) to a large extent, suggesting the activation of the DnAGL19-DnFT pathway by DnFCAβ . Taken together, these results suggest that the DnFCAγ-DnAPL1 pathway in axillary buds and the DnFCAβ-DnAGL19 pathway in the leaves cooperatively promote flowering under low temperatures. The long-term and constant, or untimely, application of high temperatures leads to the constitutive suppression of DnAPL1 by a high level of DnFCAγ in axillary buds, which consequently delays floral development.

Objective: Imipenem is a broad-spectrum carbapenem antibiotic with applications against severe bacterial infections. Here, we describe the identification of imipenem-resistant Serratia marcescens in our hospital and the role of plasmid-mediated KPC-2 expression in imipenem resistance., Materials and Methods: We used the modified Hodge test to detect carbapenemase produced in imipenem-resistant strains., Results: His resistance can be transferred to E. coli in co-culture tests, which implicates the plasmid in imipenem resistance. PCR amplification from the plasmid identified two products consistent with KPC-2 of 583 and 1050 bp that were also present in E. coli after co-culture. The restriction pattern for both plasmids was identical, supporting the transfer from the S. marcescens isolate to E. coli. Finally, gene sequencing confirmed KPC-2 in the plasmid., Conclusions: Due to the presence of KPC-2 in the imipenem-resistant S. marcescens, we propose that KPC-2 mediates antibiotic resistance in the S. marcescens isolate.

Aim: To detect the expression of Arpin, and determine its correlation with clinicopathological characteristics and the prognosis of gastric cancer (GC) patients., Methods: A total of 176 GC patients were enrolled as study subjects and classified into groups according to different clinicopathological variables. GC mucosal tissues were obtained via surgery. Another 43 paraffin-embedded tissue blocks of normal gastric epithelium (> 5 cm away from the edge of the tumor) were included in the control group. Immunohistochemistry (IHC) for the Arpin and Arp3 proteins was performed on the formalin-fixed, paraffin-embedded GC tissues. Additionally, expression of the Arpin protein in 43 normal gastric tissues was also determined using IHC., Results: Expression of the Arpin protein in GC was lower than that in normal gastric mucosa (30.68% vs 60.47%, P < 0.001). A χ 2 test of the 176 GC samples used for IHC showed that decreased Arpin expression was associated with advanced TNM stage ( P < 0.01) and the presence or absence of lymph node metastasis (80.92% vs 35.56%, P < 0.001). Additionally, a significant correlation was observed between the expression of Arpin and the presence of the Arp2/3 complex in GC tissues ( χ 2 = 30.535, P < 0.001). Moreover, a multivariate Cox regression analysis revealed that Arpin expression [hazard ratio (HR) = 0.551, P = 0.029] and TNM stage (HR = 5.344, P = 0.001) were independent prognostic markers for overall survival of GC patients. Regarding the 3-year disease-free survival (DFS), the recurrence rate of GC patients with low Arpin expression levels (median DFS 19 mo) was higher than that in the high-Arpin-expression group (median DFS 34 mo, P = 0.022)., Conclusion: Low Arpin levels are associated with clinicopathological variables and a poor prognosis in GC patients. Arpin may be regarded as a potential prognostic indicator in GC., Competing Interests: Conflict-of-interest statement: The authors declare no conflict of interest.