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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]

To effectively eliminate the deposition effect of sediment on the reservoir and avoid its secondary pollution to the water body, this paper proposes a new philosophy of the integrated dredging of pulsed water jets and air lift pumps to boost the dredging performance of the air lift pump, which can be realized by innovating a new structure of a spiral air lift pump. The influence of the number of nozzles and their ways of distribution on the dredging characteristics of the air lift pump is studied, and the developed model is used in engineering practice. The results show that the introduction of the water jet nozzle exerts little effect on the water volume JL of the air lift pumping system but can greatly increase discharge amount of solid JS. The nozzle plays the role of relieving the static pressure on the bottom, so the bottom flow field pulsates, the apparent flow rate of the solid is greatly improved, and the particles are poised to move. However, the nozzle needs to be distributed disproportionately but not too "exaggeratedly", otherwise it will easily trigger dynamic pressure, resulting in reduced lifting performance. Meanwhile, the immersion rate γ can produce a strong influence on the lifting performance. With the increase in immersion rate γ, the amount of JL and JS are greatly improved, and especially the peak of JS is as much as 10 times that under the working condition without nozzle. Based on the laboratory experiments and field tests, it can be verified that the greater the immersion rate of the air lift pump, the higher the dredging efficiency, which is especially suitable for deep-water dredging and is also consistent with the theory. [ABSTRACT FROM AUTHOR]

The paper introduced background and development status of IPv6, expounded development tendency and research direction of application of IPv6 in industrial Ethernet, and indicated all hardware and software based on mine industrial Ethernet should have dual protocol stack, and with maturity and popularization of the IPv6 technology, coal mine network equipment that only supports IPv6 protocol will be developed, such as explosion-proof network equipments, configuration softwares, drivers of data acquisition and control hardware which support IPv6.

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]

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 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.

Objective: To prepare and evaluate a new formulation of thermosensitive and ion-sensitive in situ gel for nasal administration, using the volatile oil of Bupleuri radix and baicalin, the effective component extracted from Scutellariae radix ., Methods: Formulation of in situ nasal gel of Bupleuri radix volatile oil and baicalin was prepared by using poloxamer 407 and deacetylated gellan gum as the gel base, 10% pharmasolve and 2% polysorbate 80 as the solubilizer, and 0.8% triethanolamine as the pH regulator. The physical appearance, phase transition temperature, and baicalin release performance of the prepared gel were examined. The pharmacodynamic evaluation was done with the rat fever model developed with dry yeast and the mouse auricle swelling inflammation model., Results: The phase transition temperature of the gel was optimized to be 36 ℃. The release of baicalin from the gel showed obvious features of sustained release, which accorded well the zero-order kinetics equation. The results of experiments with the rat dry yeast fever model and the mouse xylene auricle swelling inflammation model showed that the gel had significant antipyretic and anti-inflammatory effects that were significantly better than those of the groups treated with the blank gel base and the Bupleuri radix and Scutellariae radix granule. Results from the cilia toxicity test showed that the gel did not have obvious toxic effect on toad palate mucosal cilia., Conclusion: The in situ nasal gel of Bupleuri radix volatile oil and baicalin prepared in the study had a rapid onset time, high efficiency, and prolonged release of active ingredients, thus showing promises for further applicational development., (Copyright© by Editorial Board of Journal of Sichuan University (Medical Sciences).)

Based on a few bands and unabundant spectral information of TM remote sensing image, two endmember extraction algorithms are put forward. First, spatial split endmember extraction algorithm, which firstly browses the image, based on the complexity of objects, divides the image into different blocks, then uses hourglass algorithm to extract endmembers. Second, region continuity algorithm, also based on dividing-into-blocks idea, which uses extraction and classification of homogenous object algorithm and spectral correlation energy level matching algorithm to extract endmembers. Finally, comparing the two algorithms, spatial split endmember extraction algorithm runs fast, with little prior knowledge, however, the probability of error extraction endmembers exists; and region continuity algorithm's precision is higher, needs for prior knowledge, and the segment process is slow. Experimental results show that both spatial-and-spectral combined endmember extraction algorithms can effectively solve the large regional scale, multispectral endmember extraction problem, and have broad application prospects.