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Abstract In aircraft design, structural optimization concerning transonic aeroelastic issues is computationally impractical, due to a great number of aeroelastic analyses are required in iterative process. Reduced-Order Model (ROM) method is convenient for transonic aeroelastic analyses; however, current ROMs are not reusable during iteration, hence the time consumption is still too high. To solve the problem, this study proposes an improved ROM suitable for Arbitrary Mode Shapes (ROM-AMS), which is reusable in iterative process. By adopting Principal Component Analysis, ROM-AMS method significantly reduces the number of basis mode shapes, while improves the accuracy of flutter analysis. In an optimization case, the weight of a cropped delta wing is reduced by 28.46%, and the efficiency is 900 times higher than that of traditional ROM approaches, which demonstrates the feasibility of this method in aeroelastic optimization. Highlights • A Reduced-Order Modeling method for transonic aeroelastic optimization is proposed. • Number of basis modes can be largely reduced by Principal Component Analysis. • Efficiency of optimization is two orders of magnitudes higher than previous ROMs. [ABSTRACT FROM AUTHOR]

Urban green spaces play a crucial role in cities by providing near-natural environments that greatly impacts the health of residents. However, these green spaces have recently been scrutinized as potential reservoirs of antibiotic resistance genes (ARGs), posing significant ecological risks. Despite this concern, our understanding of the distribution, sources, and ecological risks associated with ARGs remains limited. In this study, we investigated the spatial distribution of soil ARGs using spatial interpolation and auto-correlation analysis. To apportion the source of soil ARGs in urban green spaces of Tianjin, Geo-detector method (GDM) was employed. Furthermore, we evaluated the ecological risk posed by ARGs employing risk quotients (RQ). The results of our study showed a significantly higher abundance of Quinolone resistance genes in the soil of urban green spaces in Tianjin. These genes were mainly found in the northwest, central, and eastern regions of the city. Our investigation identified three main factors contributing to the presence of soil ARGs: antibiotic production, precipitation, livestock breeding, and hospital. The results of ecological risk in RQ value showed a high risk associated with Quinolone resistance genes, followed by Aminoglycoside, Tetracycline, Multidrug, MLSB, Beta Lactam, Sulfonamide, and Chloramphenicol. Mantel-test and correlation analysis revealed that the ecological risk of ARGs was greatly influenced by soil properties and heavy metals. This study provides a new perspective on source apportionment and the ecological risk assessment of soil ARGs in urban green spaces. • Explore the spatial distribution of soil antibiotic resistance genes. • Identify the sources of soil antibiotic resistance genes via multiple models. • Assess the ecological risk of soil antibiotic resistance genes in urban green space. [ABSTRACT FROM AUTHOR]

[Display omitted] • M2 (PD) is the main metabolite of dammarane ginsenoside AD-1 in vivo. • Compound M3 was isolated from metabolites in vivo for the first time. • PD could significantly inhibit the proliferation and migration of MDA-MB-231 cells and induce G1-phase arrest. • PD could significantly inhibit the proliferation and migration of breast cancer in nude mice. • PD inhibited proliferation and metastasis of breast cancer cells by inducing the p38 MAPK/MMP9 pathway. Previous studies have shown that 20 (R)-25-methoxyl-dammarane-3 β , 12 β , 20 triol (AD-1) can inhibit various cancer cell lines. This study aimed to explore the effect and mechanism of AD-1 metabolite M2 (Panaxadiol; PD) on breast cancer cells of nude mice. Five AD-1 metabolites were isolated and identified using various chromatographic techniques. PD was the main component. In vitro results showed that PD could inhibit the proliferation and migration of MDA-MB-231 cells by inducing G1-phase arrest. In addition, PD down-regulated the expression of Cyclin D1, cdk2, cdk4, cdk6, P-p38, and MMP9, and up-regulated p21 and p27. In vivo results showed that PD could effectively reduce the volume, weight, and migration of breast cancer Transcriptomics analyzed 491 differentially expressed genes by GO and KEGG enrichment. RT-PCR verification confirmed that the significant down-regulation of MMP9 was consistent with transcriptomics results. In further research showed that PD regulated the protein expression of P-p38 and MMP9 in MAPK pathway. In summary, in vivo and in vitro studies showed that PD significantly inhibit the occurrence and development of breast cancer, possibly through the MAPK pathway. [ABSTRACT FROM AUTHOR]

Abstract: An integrative non-conjugative extrachromosomal genetic element, denoted as pSSVi, has been isolated from a Sulfolobus solfataricus P2 strain and was characterized. This genetic element is a double-stranded DNA of 5740 bp in size and contains eight open reading frames (ORFs). It resembles members of the pRN plasmid family in genome organization but shows only weak similarity to the latter in conserved regions. pSSVi has a copG gene similar to that of a pRN plasmid, encodes a large replication protein which, unlike a typical pRN RepA, contains no polymerase/primase domain, and lacks the plrA gene. Interestingly, pSSVi encodes an SSV-type integrase which probably catalyzes the integration of its genome into a specific site (a tRNAArg gene) in the S. solfataricus P2 genome. Like pSSVx, pSSVi can be packaged into a spindle-like viral particle and spread with the help of SSV1 or SSV2. In addition, both SSV1 and SSV2 appeared to replicate more efficiently in the presence of pSSVi. Given the versatile genetic abilities, pSSVi appears to be well suited for a role in horizontal gene transfer. [Copyright &y& Elsevier]

• For the first time, 16 metabolites of 20(R)-25-OCH 3 -PPD were isolated and identified, of which 10 were new compounds. • We first discovered the biotransformation of dammarane-type sapogenins into oleanane-type sapogenins in rats, found a series of metabolites that changed mainly at C-29. • We studied the anticancer mechanisms of active oleanane-type sapogenin (M6). All the results suggested that M6 manifested higher efficacy on inhibiting cancer cells proliferation by inducing cell apoptosis. 20(R)-25-methoxyl-dammarane-3 β ,12 β ,20-triol (AD-1, CN Patent: 201010107476.7) is a novel derivative of dammarane-type ginsenoside. AD-1 has been shown to inhibit cancer cell proliferation without significant host toxicity in vivo , and has excellent development potential as a new anti-cancer agent. This study was designed systematically to explore the metabolic pathway of ginseng sapogenins. The metabolism of drugs in the body is a complex biotransformation process where drugs are structurally modified to different molecules (metabolites) through various metabolizing enzymes. The compounds responsible for the effects of orally administered ginseng are believed to be metabolites produced in the gastrointestinal tract, so understanding the metabolism of the drug candidate can help to optimize its pharmacokinetics. In this study, faeces samples were collected and extracted after oral administration of AD-1. The 16 metabolites of AD-1 were isolated and identified for the first time with various chromatographic techniques, including semi-preparative high performance liquid chromatography, nuclear magnetic resonance spectroscopy, and mass spectrometry; of these 16 metabolites, 10 were novel compounds. We first discovered the biotransformation of dammarane-type sapogenins into oleanane-type sapogenins in rats and found a series of metabolites that changed, mainly at C-25 and C-29. This study provides new ideas for the metabolic pathway of ginseng sapogenins. The isolated compounds were screened for their effect on the viability and proliferation against cancer cell lines (Human A549, MCF-7, HELA, HO-8901 and U87). The discovery of novel active metabolites 3 β ,12 β ,21 α ,22 β -Hydroxy-24-norolean-12-ene (M6) may lead to a new or improved drug candidate. For one, M6 could inhibit the growth of all the tested cancer cells. Among the tested cell lines, M6 exhibited the most remarkable inhibitory effect on ovarian cancer HO-8901 cells, with IC 50 value of 2.086 μM. On this basis, we studied the anticancer mechanisms of M6. The results indicated that the pro-apoptotic feature of M6 acts via a mitochondrial pathway. Our results indicated that M6 exhibited a higher inhibitory effect on cancer-cell proliferation than AD-1 by inducing cell apoptosis. Our work provides data for future investigations on the metabolic mechanism of AD-1 in vivo and the potential for future research on developing a new drug. [ABSTRACT FROM AUTHOR]