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Seven undescribed polyoxygenated ursane-type triterpenoids (vitnegundins A−G), three undescribed triterpenoid saponins (vitnegundins H−J), and 17 known ones were isolated from an EtOH extract of the aerial parts of Vitex negundo L. The structures of the undescribed compounds were established by extensive spectroscopic analysis. The absolute configurations of vitnegundins A, B, and E were determined by single-crystal X-ray diffraction data. Vitnegundins B−D are pentacyclic triterpenoids possessing rare cis -fused C/D rings and vitnegundins C–H represent undescribed ursane-type triterpenoids with 12,19-epoxy moiety. In the biological activity assay, vitnegundin A, vitnegundin E, and swinhoeic acid displayed inhibitory effects against LPS-induced NO release in BV-2 microglial cells, with IC 50 values of 11.8, 44.2, and 19.6 μM, respectively. [Display omitted] • Ten undescribed triterpenoids or triterpenoid saponins were isolated from Vitex negundo. • The absolute configurations of some undescribed triterpenoids were determined by X-ray data. • Three compounds inhibited NO release in LPS-induced BV-2 microglial cells. [ABSTRACT FROM AUTHOR]

This paper studies the verification and enforcement of deadlock-freeness and liveness in partially controllable Petri nets. First, we introduce a particular type of basis reachability graphs called conflict-free-control-explicit basis reachability graphs (CFCE-BRGs), in which the firings of all structurally conflicting transitions and all controllable ones are explicitly encoded. We propose two sufficient and necessary conditions for verifying deadlock-freeness and liveness of a Petri net; both can be verified by inspecting a CFCE-BRG using graph theory. Moreover, we develop two maximally permissive deadlock-freeness and liveness enforcing supervisors based on the trimming of CFCE-BRGs. The developed approaches are applicable to arbitrary bounded Petri nets, without an exhaustive reachability space enumeration. [ABSTRACT FROM AUTHOR]

• Two slender CFST double-column piers are tested under cyclic loading. • The prefabricated connections guarantee the performance of the novel pier system. • FE modeling is carried out to assess seismic performance of pier systems. • The novel pier systems have application potential in bridges of mountain areas. This paper investigates the seismic behavior of a prefabricated thin-walled concrete-filled steel tubular (CFST) pier system composed of circular thin-walled CFST double-column, I-shaped steel beam, and precast reinforced concrete (RC) cap beam. Hysteretic tests were conducted on two slender double-column pier systems: one with prefabricated connections (prefabricated pier system), and the other one with traditional embedded connections (traditional pier system). The test results indicated that, compared with the traditional pier system, the pier system with prefabricated connections demonstrating an 18 % increase in lateral resistance and a 5 % higher ductility coefficient, despite the weld of the steel beam cracked prematurely. Finite-element numerical models were established based on the OpenSees platform and validated by the cyclic loading tests. A comprehensive investigation involving a total of 12 cases, encompassing both CFST piers and RC piers, was conducted to evaluate their seismic performance and economic efficiency. The analysis results revealed that the proposed prefabricated pier system offers notable advantages in seismic performance for both tall and low piers. [ABSTRACT FROM AUTHOR]

This study aims to profoundly investigate the seismic performance and application prospect of the typical continuous beam bridge with the novel prefabricated concrete-filled steel tubular (CFST) piers, with advantages in simple on-site assembly, convenient transportation of prefabricated components, good seismic performance, and low construction cost. According to two prototype continuous beam bridges respectively equipped with low and tall typical reinforced concrete (RC) piers, 7 bridge cases with prefabricated CFST piers featuring various configurations of the tie beams are designed. Three-dimensional numerical models of these bridge cases are established and verified with the previous experimental studies, and numerical simulations of all the bridge cases are conducted to assess and compare the seismic responses and fragility curves. The results show that the bridges with prefabricated CFST piers exhibit a reduction in top pier transversal displacement and maximum curvature along the pier height, which are 43 % and 138 % lower than those of the prototype RC piers, respectively. Besides, the bridges with prefabricated CFST piers generally present lower probabilities of being damaged compared to those of the prototype bridges with RC piers. • Assess the seismic behavior of the bridges with CFST piers by numerical method. • Design the bridges with CFST piers based on the prototype bridges. • The bridges with CFST piers exhibit a reduction in seismic responses. • Damage probabilities of CFST piers are lower than those of RC piers. [ABSTRACT FROM AUTHOR]

As inclusions are inevitable from the material-producing processes, an engineering concept regarding multiple features of them is needed for material design. In this study, a unique approach integrating physical-meaningful microstructure-sensitive models with the machine-learning-based data-driven model is proposed to reveal the complex relationship between the fatigue life of materials with intrinsic features of inclusions including size, stiffness, thermal properties, and extrinsic stress amplitudes. This high-fidelity presentation of the relation of these variables enables a detailed and systematic analysis of the effects of inclusions on fatigue life. The data-based phase map provides a designing envelope of inclusion features for fatigue-resistant steels. [Display omitted] • Machine-learning-based approach is integrated with microstructure-sensitive modeling for fatigue life prediction. • The integrated approach shows great predictive capability in the effect of multiple inclusions features on fatigue. • These features include size, Young's modulus, and thermal expansion coefficient of inclusions and applied stresses. • High-fidelity big data is generated by the machine-learning-based model within seconds. • The data-driven phase map provides an instant prediction of fatigue life and a guide for inclusion engineering. [ABSTRACT FROM AUTHOR]

Abstract Amorphous SiOC films were synthesized by magnetron sputtering at room temperature with/without radio frequency (RF) bias and further improved in terms of mechanical properties by ion irradiation. As-deposited SiOC films without RF bias exhibit catastrophic failure at a low stress and strain, which is ascribed to microstructural heterogeneities associated with the formation of voids during deposition, as evidenced by transmission electron microscopy. Ion irradiation unifies microstructure accompanied with eliminating the voids, resulting in a simultaneously increase in strength and plasticity (ultimate strength of 5–7 GPa and the strain to shear instability of over 20%). Homogeneous microstructures are demonstrated to ensure high strength and plasticity of amorphous SiOC, as observed in SiOC that are deposited with RF-bias. Thus, microstructural homogeneous amorphous SiOC exhibits intrinsically high strength and plasticity, making them promising as structural engineering materials. Graphical abstract Image 1 Highlights • Mechanical properties of amorphous SiOC were investigated by in-situ SEM compression. • Irradiation increases both strength and plasticity by improving film quality. • Microstructural homogeneous amorphous SiOC are intrinsically strong and deformable. [ABSTRACT FROM AUTHOR]

Highlights • GELP genes were associated with fruit ripening. • Genes related to auxin-responsive protein were identified involved in fruit ripening. • The SAUR genes may regulated fruit ripening by integrating auxin signal into ethylene signal. • Ripening is a kind of stress to fruit in a sense and evokes several genes belonging to stress/defense up-regulated. • Photosynthesis should be diminished during fruit ripening in peach. Abstract Fruit ripening is determined by the coordinated action of multi-faceted biological processes. However, little is known about the molecular mechanism of fruit ripening in peach. To explore the genes involved into fruit ripening, in this study, transcriptome sequencing was conducted in the peach fruits at the stone hardening, the second rapid growth, and ripening stages. By comparing the expression levels of whole genes between the ripening (LYE) and developing fruits (LYD and LYC), 1 615 and 1 938 genes were up- and down-regulated in the ripening fruits. In these differential expressed genes, the PG , PL8 , and XTH33 genes related to cell wall degradation were up-regulated in ripening fruits, in contrast, two GDSL genes against the xyloglucan oligosaccharides were down regulated. The CABs, photosystem I/II , and OEE genes involved in photosynthesis were detected having the lowest expression levels in the ripening fruits. The genes associated with ethylene response, biosynthesis, and auxin-responsive were remarkably increased in expression levels in ripening fruits. The stress related genes UP3 , EDR2L , PR1 , PR4 and programmed cell death gene ACD11 also displayed an up-regulation trends during fruit ripening. Few ripening-related transcription factors, such as NAC , MADS-box , and MYB , were also detected from the differential expressed genes. Moreover, expression patterns of the selected genes were tested by real-time quantitative PCR (qRT-PCR), and the qRT-PCR results were consistent with transcriptome data. This study provides important candidate genes for exploring the complex metabolic process involved in ripening. [ABSTRACT FROM AUTHOR]

Highlights • Phylogenetic and expression analyses of all the 70 homeobox genes in peach fruits. • A homeobox gene, PpHB.G7, mediates ethylene biosynthesis during fruit ripening. • The PpHB.G7 could interact with the promoters of ethylene biosynthesis genes. • Seven HD-ZIP homeobox genes are differentially expressed in the developmental fruits. Abstract Homeobox transcription factors belong to a superfamily that has been widely studied in plant growth and development, but little is known regarding their role in fruit development and ripening. Using a genome-wide expression analysis of homeobox (HB) genes and quantitative real-time PCR, a HD-ZIP II member, PpHB.G7 , which presented higher levels of expression in ripening fruits than in developing fruits in all of the tested cultivars, was isolated from peach. Transient transformations showed that PpHB.G7 affects ethylene production and the expression of ethylene biosynthesis genes (PpACS1 and PpACO1). Both dual-luciferase and yeast one-hybrid assays confirmed that PpHB.G7 interacts with the promoters of PpACS1 and PpACO1. Thus, PpHB.G7 mediates ethylene biosynthesis by stimulating PpACS1 and PpACO1 activities. Furthermore, we also found that the other eight HB genes were differentially expressed in the developing fruits, with seven of these genes belonging to the HD-ZIP family. These results suggest that the HB genes in the HD-ZIP family play important roles in fruit development and ripening. [ABSTRACT FROM AUTHOR]

Abstract Reliability evaluation was important for safe operation of the power system. In order to evaluate the reliability of power system quickly, this paper provided to use a dynamic fault set recording method combined with isodisperse important sampling method to improve the evaluation efficiency. At the same time, dynamic parallel strategy was used to improve the calculating speed. The simulation example verified the effectiveness and practicality of the method. [ABSTRACT FROM AUTHOR]

Background: Hovenia dulcis Thunb. is considered as a traditional herbal medicine that has been used in the treatment for ethanol-induced liver disease for centuries. Recently, substantial studies demonstrated that Semen hoveniae extract (SHE) not only suppressed the hepatic steatosis caused by chronic ethanol exposure, but also inhibited lipopolysaccharide-stimulated inflammatory responses. Nevertheless, the underlying molecular mechanisms largely remained elusive.Aim: To determine the hepatoprotective effects of SHE on ethanol-triggered liver damage and further elucidate its potential mechanisms.Methods: In the present study, the Sprague-Dawley rats were fed with the Lieber-DeCarli diet containing alcohol or isocaloric maltose dextrin as control diet with or without SHE (300 and 600 mg/kg/d bw) for 8 weeks. The levels of serum biomarkers (ALT, AST and LDH) and LPS were detected by biochemical assay kits and endotoxin detection LAL kit, respectively. The histopathological changes of liver and intestinal tissues were observed by hematoxylin and eosin (H&E) staining and Transmission electron microscope (TEM). The expressions of CD14, TLR4, MyD88, NF-κB, Iκ-B, P-Iκ-B and TNF-α in liver, and ZO-1 and occludin in intestine were determined by western blot. The faecal microbial composition was determined by16S rRNA Gene Sequencing Analysis.Results: Biochemical and histopathological analysis revealed that SHE significantly alleviated the lipid deposition and inflammation response in liver induced by ethanol. SHE remarkably inhibited the TLR4 pathway and its downstream inflammatory mediators, and up-regulated the expressions of ZO-1 and occludin in the intestine. The further investigations suggested SHE dramatically reversed ethanol-induced alterations in the intestinal microbial flora and decreased the generation of gut-derived endotoxin.Conclusion: In summary, SHE probably modulated abnormalities of gut-liver axis and inhibited TLR4-associated inflammatory mediators activation to exert its hepatoprotective properties. These findings suggested that SHE as a traditional therapeutic options which may play an essential role in protecting against the chronic ethanol-triggered liver injury. [ABSTRACT FROM AUTHOR]

Drying and rewetting events of soil represents a common physiological stress for soil microbial communities. We investigated the effect of alternate drying-rewetting cycles on N 2 O emissions and soil microbial communities in jar experiments with soil samples. The results showed that instant flooding and air-drying moments are two important steps of soil drying and rewetting periods influencing soil microbial communities and N 2 O emissions. N 2 O fluxes in the air dry (AD) steps were always higher than those in the instant flooding (IF) steps, especially in the early stages of AD and IF. The soil treated with long-term organic matter and chemical fertilizer promoted N 2 O emissions but inhibited the N 2 O release from newly applied urea when soil went through drying and rewetting events. Soil moisture content(s) also significantly affected the growth of ammonia oxidiser and denitrifier communities, with the functional gene abundance increasing with increasing soil moisture content. While comparing first and second cycles, N 2 O fluxes were six times higher in the first cycle than in the second cycle. It is concluded that sudden changes in moisture condition influenced the N 2 O flux, and nitrifier and denitrifier functional genes by affecting the growth of ammonia oxidiser and denitrifier communities. [ABSTRACT FROM AUTHOR]

Anaerobic ammonium oxidation (anammox) is an important process in many marine and paddy ecosystems. However, few studies have reported on the contribution to the nitrogen cycle of anammox and its dynamics in rice–wheat cropping systems with different fertilization regimes. Here, isotope tracing and molecular techniques were used to determine the potential rates of anammox and their association with bacterial abundance, diversity, and activity. Rice–wheat cropping systems at two sites in Jiangsu Province, China were selected and the treatments at each site were: 1) no fertilization (CK), 2) 100% chemical fertilization (CF), 3) pig manure compost plus 50% chemical fertilization (PMCF), and 4) straw plus 100% chemical fertilization (SRCF). The results revealed that anammox bacteria with high abundance were detected in both the wheat and rice seasons. The abundance of anammox in PMCF treatment was higher than that in SRCF treatment in both Changshu and Jintan. Moreover, the abundance of anammox bacteria in CF treatment was significantly higher than that in CK in Changshu. Analysis of anammox hydrazine synthase β subunit ( hzs-β ) gene sequences showed that in the rice season, the anammox bacteria Ca. Brocadia, Ca. Scalindua, and Ca. Jettenia were present. In contrast, all of the anammox hydrazine oxidase ( hzo ) genes were affiliated with Ca. Brocadia, suggesting that hzs genes are more representative of anammox biological diversity compared to hzo . Sequences from the PMCF treatment where affiliated with both Ca. Jettenia and Ca. Brocadia, and showed the highest diversity. Anammox activity was detected in both the wheat and rice seasons, but there were significant differences between seasons. The anammox rates were in the range 0.34 to 1.04 nmol dinitrogen gas ∙ g − 1 dry soil ∙ h − 1 , and 3.15 to 9.62% of dinitrogen gas emissions were attributed to anammox. However, no significant difference among the fertilizer treatments for anammox activity was found in the study. [ABSTRACT FROM AUTHOR]