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The intrinsic characteristics of multiphase flow inevitably result in vibrations within the pipe structure. The evolution of vibration characteristics is crucial for monitoring the stability of the multiphase flow pipelines. However, under high liquid velocity condition, the influence of flow pattern on the gas–liquid two-phase flow-induced vibration (GTFIV) of the pipe remains unclear. In this paper, the vibration signals in the horizontal pipe under different flow patterns at high liquid velocity are measured by a vibration test system. Synchronously, images inside the pipe are captured to illustrate the flow mechanism. The results show that the α stable distribution model holds higher fitting accuracy than the standard normal distribution for the GTFIV. The random behavior of small-scale bubbles determines the structural richness of the GTFIV. The multifractal characteristics of the GTFIV are strongly dependent on the flow pattern. The formation of the gas plug leads to significant unevenness in the fractal structure of the GTFIV. The multifractal strength of the GTFIV gradually increases as the flow pattern transforms from dispersed bubble flow to slug flow. Some multifractal spectrum parameters of the vibration signal can be applied for the identification of flow patterns in the pipe. [ABSTRACT FROM AUTHOR]

Hysteresis effect, which has a significant impact on transient characteristics of a pump-turbine, attracts more and more researchers' attention and shows great potential. Influences of hysteresis on dynamic characteristics of a pump-turbine are investigated during the transient process in this paper. Transient trajectories of pump-turbines actually do not match their static operation trajectories, especially in the condition of turbine braking. In order to establish a transient model of a pump-turbine in different moving directions of dynamic trajectories, time delays among the relative parameters are introduced in this paper. Furthermore, effects of hysteresis on the dynamic characteristics of the pump-turbine are analyzed in detail by using numerical simulation. Based on the established transient model, influences of unit head on the dynamic characteristics of the pump-turbine are studied during the bidirectional transient process. The simulation results show the transient characteristic of the pump-turbine can be improved with the enhancement of hysteresis effect. While it gradually loses stability with the increase of hysteresis. The conclusions provide us a new approach for regulating the transient performance and stability of pump-turbines by using hysteresis effect during transient process. [ABSTRACT FROM AUTHOR]

Abstract: An on‐line high‐performance liquid chromatography–biochemical detection (HPLC‐BCD) method, in which compounds separated by HPLC were on‐line reacted with enzyme and substrate solutions delivered by flow injection and the enzyme inhibition signal was collected by UV detection, was developed to rapidly screen α‐glucosidase inhibitors from green tea extracts in this study. The chromatographic fingerprints and enzyme inhibition profiles of the different brands of green tea could be simultaneously detected by the on‐line HPLC‐BCD method. Enzyme inhibition profiles were detected by the UV detector at 415 nm based on the reaction of α‐glucosidase and p‐nitrophenyl α‐ d‐glucopyranoside (PNPG). PNPG (1.25 m m), α‐glucosidase (0.4 U/mL) and the flow rate 0.07 mL/min were applied as optimized parameters to detect α‐glucosidase inhibitors in green tea. Four components in green tea showed α‐glucosidase inhibition action and three of them were identified as HHDP‐galloyl glucose, (−)‐epigallocatechin‐3‐gallate and (−)‐epicatechin‐3‐gallate by HPLC–fourier‐transform mass spectrometry (HPLC‐FTMS). Two brands of green tea derived from Mengding and Enshi mountainous areas might be superior to the other samples in the prevention and treatment of diabetes owing to their stronger activities of enzyme inhibitors. The proposed on‐line HPLC‐BCD method could be used to rapidly identify the potential enzyme inhibitors in complex matrixes. [ABSTRACT FROM AUTHOR]

Gd-doped BiWO nanoparticles were successfully prepared through microwave assisted synthesis. The incorporation of Gd ions into BiWO crystallite was analyzed by X-ray diffraction, energy dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy. The optical properties of the nanoparticles were characterized by UV-Vis absorption and photoluminescence spectroscopy. The photocatalytic activity of the nanoparticleswas investigated by degradation of Rhodamine B under visible-light irradiation. Our results showed that Gd-doping plays an important role for enhancing the visible light photocatalytic activity, and the enhanced photocatalytic activity of Gd-doped BiWO nanoparticles would be mainly correlated with the effective decrease of recombination rate of photogenerated electron-hole pairs. [ABSTRACT FROM AUTHOR]

In the present study, the complete mitochondrial genome sequence of Arctic fox (Alopex lagopus) was determined for the first time. It has a total length of 16,656 bp, and contains 13 protein-coding genes, 22 tRNA genes, 2 ribosome RNA genes and 1 control region. The nucleotide composition is 31.3% for A, 26.2% for C, 14.8% for G and 27.7% for T, respectively. The D-loop region located betweentRNAProandtRNAPhecontains a (ACACGTACACGCAT)18tandem repeat array. The data will be useful for the investigation of the genetic structure and diversity in the natural and farmed population of Arctic foxes. [ABSTRACT FROM AUTHOR]

The plant-specific Teosinte-branched 1/Cycloidea/Proliferating (TCP) transcription factor genes are involved in plants' development, hormonal pathways, and stress response but their evolutionary history is uncertain. The genome-wide analysis performed here for 47 plant species revealed 535 TCP candidates in terrestrial plants and none in aquatic plants, and that TCP family genes originated early in the history of land plants. Phylogenetic analysis divided the candidate genes into Classes I and II, and Class II was further divided into CYCLOIDEA (CYC) and CINCINNATA (CIN) clades; CYC is more recent and originated from CIN in angiosperms. Protein architecture, intron pattern, and sequence characteristics were conserved in each class or clade supporting this classification. The two classes significantly expanded through whole-genome duplication during evolution. Expression analysis revealed the conserved expression of TCP genes from lower to higher plants. The expression patterns of Class I and CIN genes in different stages of the same tissue revealed their function in plant development and their opposite effects in the same biological process. Interaction network analysis showed that TCP proteins tend to form protein complexes, and their interaction networks were conserved during evolution. These results contribute to further functional studies on TCP family genes. [ABSTRACT FROM AUTHOR]

The plant-specific WUSCHEL-related homeobox (WOX) transcription factor gene family is important for plant growth and development but little studied in oil crops. We identified and characterized 58 putative WOX genes in Brassica napus (BnWOXs), which were divided into three major clades and nine subclades based on the gene structure and conserved motifs. Collinearity analysis revealed that most BnWOXs were the products of allopolyploidization and segmental duplication events. Gene structure analysis indicated that introns/exons and protein motifs were conserved in each subclade and RNA sequencing revealed that BnWOXs had narrow expression profiles in major tissues and/or organs across different developmental stages. The expression pattern of each clade was highly conserved and similar to that of the sister and orthologous pairs from Brassica rapa and Brassica oleracea. Quantitative real-time polymerase chain reaction showed that members of the WOX4 subclade were induced in seedling roots by abiotic and hormone stresses, indicating their contribution to root development and abiotic stress responses. 463 proteins were predicted to interact with BnWOXs, including peptides regulating stem cell homeostasis in meristems. This study provides insights into the evolution and expression of the WOX gene family in B. napus and will be useful in future gene function research. [ABSTRACT FROM AUTHOR]

The Spotted dove (Streptopelia chinensis) is a member of the bird family Columbidae. In this study, we report the complete mitochondrial genome of this species. The mitochondrial genome of Spotted dove is a circular molecule of 16,966 bp in size and contains 13 protein-coding genes, two rRNA genes, 22 tRNA genes, and one control region. The total base composition is 30.1% for A, 32.1% for C, 13.9% for G, and 23.9% for T. These data will be useful for the phylogenetic and population diversity analyses of birds, especially Columbidae species. [ABSTRACT FROM AUTHOR]

Chronic liver injury leads to progressive liver fibrosis and ultimately cirrhosis, a major cause of morbidity and mortality worldwide. However, there are currently no effective anti-fibrotic therapies available, especially for late-stage patients, which is partly attributed to the major knowledge gap regarding liver cell heterogeneity and cell-specific responses in different fibrosis stages. To reveal the multicellular networks regulating mammalian liver fibrosis from mild to severe phenotypes, we generated a single-nucleus transcriptomic atlas encompassing 49 919 nuclei corresponding to all main liver cell types at different stages of murine carbon tetrachloride (CCl 4 )-induced progressive liver fibrosis. Integrative analysis distinguished the sequential responses to injury of hepatocytes, hepatic stellate cells and endothelial cells. Moreover, we reconstructed cell-cell interactions and gene regulatory networks implicated in these processes. These integrative analyses uncovered previously overlooked aspects of hepatocyte proliferation exhaustion and disrupted pericentral metabolic functions, dysfunction for clearance by apoptosis of activated hepatic stellate cells, accumulation of pro-fibrotic signals, and the switch from an anti-angiogenic to a pro-angiogenic program during CCl 4 -induced progressive liver fibrosis. Our dataset thus constitutes a useful resource for understanding the molecular basis of progressive liver fibrosis using a relevant animal model.