Numerical simulations and surrogate-based optimization of cavitation performance for an aviation fuel pump

Xing’an Zhao,Biao Huang,Tairan Chen,Guoyu Wang,Deming Gao,Jing Zhao 대한기계학회 2017 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.31 No.2

We used computational modeling to investigate the cavitation performance of an aviation fuel pump, and optimize structural parameters using the surrogate-based method. In the numerical simulation, a rotation-curvature correction was adapted to the k-ε turbulence model, and a four-component surrogate fuel was selected to reproduce the physical properties of the China RP-3 kerosene. Then the performance of the aviation fuel pump was predicted. In the optimization, based on the series of the numerical results, Surrogate-based analysis and optimization (SBAO) was used to optimize the structural parameters of the fuel pump (the variation of the outlet blade angle for the inducer △β b1 and the variation of the inlet blade angle for the impeller △β b2 ). The results show that the prediction of cavitation performance agrees well with the experimental data. The results show that cavitation areas are mainly distributed in the inlet of the inducer. The volume of cavities grows with the decreasing NPSHa. The head of the fuel pump has a sudden head-drop when NPSHa ≤ 5.64 m. Furthermore, the surrogate-based approach is available in structural optimization of the fuel pump. The cavitation performance of the optimized pump improved about 22 % with a little drop of head coefficient when △β b1 = 4.33° and △β b2 = 3.24°. The numerical approach employed in this paper can accurately predict the cavitating flow of the high rotating speed fuel pump and the surrogate-based method is available in the structural optimization for a better cavitation performance.

LncRNA SNHG20 promotes cell proliferation and invasion by suppressing miR-217 in ovarian cancer

Xing Xuefeng,An Ming,Chen Tonghua 한국유전학회 2021 Genes & Genomics Vol.43 No.9

Background Ovarian cancer is the most common female gynecological malignancy. SNHG20, as a long non-coding RNA, has been proven to be an important regulator in the occurrence and development of various tumors. However, the potential mechanism of SNHG20 in ovarian cancer is unclear. Objective The present study was aimed to investigate the functions and mechanisms of SNHG20 in ovarian cancer. Methods The expression of SNHG20 and miR-217 in ovarian cancer tissues and cell lines was detected by qRT-PCR. CCK-8 assay was used to measure cell proliferation in transfected cells. The transwell assay was used to detect the relative invasion rate of transfected cells. The putative binding sites between SNHG20 and miR-217 were predicted by software LncBase v.2, and the interaction between SNHG20 and miR-217 was confrmed by dual-luciferase reporter assays and RIP assay. The rescue experiments were used to illustrate potential mechanisms. Results SNHG20 was upregulated in ovarian cancer tissues and cell lines. Overexpression of SNHG20 promoted ovarian cancer cell proliferation and invasion. MiR-217 was downregulated in ovarian cancer tissues and cells, and was negatively regulated by SNHG20. Moreover, miR-217 overexpression inhibited ovarian cancer cell proliferation and invasion. Furthermore, miR-217 mimic reversed the inhibitory efect of SNHG20 overexpression on the biological behavior of ovarian cancer cells. Conclusions SNHG20 promoted cell proliferation and invasion by sponging miR-217 in ovarian cancer. These results suggested that SNHG20 and miR-217 might provide new targets for therapeutic application in ovarian cancer.

Metabotyping of the <i>C. elegans sir-2.1</i> Mutant Using <i>in Vivo</i> Labeling and ¹³C-Heteronuclear Multidimensional NMR Metabolomics

An, Yong Jin,Xu, Wen Jun,Jin, Xing,Wen, He,Kim, Hyesook,Lee, Junho,Park, Sunghyouk American Chemical Society 2012 ACS chemical biology Vol.7 No.12

<P>The roles of <I>sir-2.1</I> in <I>C. elegans</I> lifespan extension have been subjects of recent public and academic debates. We applied an efficient workflow for <I>in vivo</I><SUP>13</SUP>C-labeling of <I>C. elegans</I> and <SUP>13</SUP>C-heteronuclear NMR metabolomics to characterizing the metabolic phenotypes of the <I>sir-2.1</I> mutant. Our method delivered sensitivity 2 orders of magnitude higher than that of the unlabeled approach, enabling 2D and 3D NMR experiments. Multivariate analysis of the NMR data showed distinct metabolic profiles of the mutant, represented by increases in glycolysis, nitrogen catabolism, and initial lipolysis. The metabolomic analysis defined the <I>sir-2.1</I> mutant metabotype as the decoupling between enhanced catabolic pathways and ATP generation. We also suggest the relationship between the metabotypes, especially the branched chain amino acids, and the roles of <I>sir-2.1</I> in the worm lifespan. Our results should contribute to solidifying the roles of <I>sir-2.1</I>, and the described workflow can be applied to studying many other proteins in metabolic perspectives.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/acbcct/2012/acbcct.2012.7.issue-12/cb3004226/production/images/medium/cb-2012-004226_0006.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/cb3004226'>ACS Electronic Supporting Info</A></P>

Preparation of activated carbon spheres and their electrochemical properties as supercapacitor electrode

An Xin,Xing Guannan,Wang Jing,Tian Yanhong,Liu Yunfang,Wan Qiong 한국탄소학회 2021 Carbon Letters Vol.31 No.4

The carbon spheres (CSs) synthesized by an ultrasonic-spray pyrolysis method were activated for supercapacitor electrode. There are plenty of cracks on the surface of the activated carbon spheres (ACSs), which expend with increasing the activation temperature and activator dosage. The specifc capacitance of ACSs increases with the activation temperature and activator dosage and reach to maximal value at certain conditions. Importantly, the ACS sample activated at relatively low activation temperature (600 °C) and 7 of mass ratio of KOH to CSs has the highest specifc capacitance (about 209 F g−1 at 50 mA g−1 of current density) and indicates the excellent cycling stability after 1000 consecutive charge–discharge cycles. Furthermore, the graphene sheets could be found in the samples that were activated at 1000 °C. And the electrode prepared by the sample has the very low series resistance because of the excellent conductivity of the formed graphene sheets.

Contribution of Lipids in Honeybee (Apis mellifera) Royal Jelly to Health

Xing-An Li,Chaoqun Huang,Yun-Bo Xue 한국식품영양과학회 2013 Journal of medicinal food Vol.16 No.2

Honeybee (Apis mellifera) royal jelly (RJ) has a long history in human medicine because of its health-protecting properties. To develop a fundamental and comprehensive understanding of lipids in RJ, this article reviews the available literature on lipid compounds identified from RJ extracts and in vitro pharmacological effects of 10-hydroxy-2-decenoic acid in RJ and other closely related compounds, some of which are also identified as lipid compounds in RJ. Overall, the lipids in RJ are composed of mostly (aliphatic) fatty acids, almost all of which are present as free fatty acids and scarcely any as esters. Most fatty acids in RJ are medium-chain fatty acids, whether hydroxylated in terminal and/or internal positions, terminated with mono- or dicarboxylic acid groups, and saturated or monounsaturated at the 2-position. Besides these fatty acids, lipids in RJ contain sterols in minor amounts. Lipids in RJ are useful as preventive and supportive medicines with functionalities that include potential inhibitors of cancer growth, immune system modulators, alternative therapies for menopause, skin-aging protectors, neurogenesis inducers, and more. Taken together, the evidence suggests that health-protecting properties of RJ can be, in part, ascribed to actions of lipids in RJ.

Behavior of headed shear stud connectors subjected to cyclic loading

Fa-xing Ding,Guo-an Yin,Hai-bo Wang,Liping Wang,Qiang Guo 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.25 No.6

The objective of this study is to investigate the actual behavior of studs in structures under earthquake load through laboratory tests and numerical simulation. A test program including eighteen specimens was devised with consideration of different concrete strengths and stud diameters. Six of specimens were subjected to monotonically increasing loading while the others were subjected to cyclic loading. Mechanical behavior including the failure mechanism, load-slip relationship, stiffness degradation, energy dissipation and the damage accumulation was obtained from the test results. An accurate numerical model based on the ABAQUS software was developed and validated against the test results. The results obtained from the finite element (FE) model matched well with the experimental results. Furthermore, based on the experimental and numerical data, the design formulas for expressing the skeleton curve were proposed and the simplified hysteretic model of load versus displacement was then established. It is demonstrated that the proposed formulas and simplified hysteretic model have a good match with the test results.

Enhancement of phagocytosis and cytotoxicity in macrophages by tumor-derived IL-18 stimulation?

( Hen An Xu ),( Naoka Toyota ),( Xing Yan Jiang ),( Yuuki Fujita ),( Zhi Jun Huang ),( Maki Touma ),( Qiong Wu ),( Kenkichi Sugimoto ) 생화학분자생물학회 2014 BMB Reports Vol.47 No.5

Inoculation of mice with the murine NFSA cell line caused theformation of large tumors with necrotic tumor cores. FACSanalysis revealed accumulations of CD11b+ cells in the tumors. Microarray analysis indicated that the NFSA cells expressed ahigh level of the pro-inflammatory factor interleukin-18 (il-18),which is known to play a critical role in macrophages. However, little is known about the physiological function ofIL-18-stimulated macrophages. Here, we provide directevidence that IL-18 enhances the phagocytosis of RAW264 cellsand peritoneal macrophages, accompanied by the increasedexpression of tumor necrosis factor (tnf-α), interleukin-6 (il-6)and inducible nitric oxide synthase (Nos2). IL-18-stimulatedRAW264 cells showed an enhanced cytotoxicity to endothelialF-2 cells via direct cell-to-cell interaction and the secretion ofsoluble mediators. Taken together, our results demonstrate thattumor-derived IL-18 plays an important role in the phagocytosisof macrophages and that IL-18-stimulated macrophages maydamage tumor endothelial cells.[BMB Reports 2014; 47(5): 286-291]

Expression and Characterization of Protein Latcripin-3, an Antioxidant and Antitumor Molecule from Lentinula edodes C91-3

Ann, Xiao-Hua,Lun, Yong-Zhi,Zhang, Wei,Liu, Ben,Li, Xing-Yun,Zhong, Min-Tao,Wang, Xiao-Li,Cao, Jing,Ning, An-Hong,Huang, Min Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

In this study, an anti-oxidant and anti-tumor protein Latcripin-3 of Lentinula edodes C91-3 was expressed in Escherichia coli. for the first time. According to the cDNA library, the full-length gene of Latcripin-3 was cloned by the methods of 3'-full rapid amplification of cDNA Ends (RACE) and 5'-full RACE. The structural domain gene of Latcripin-3 was inserted into the pET32 a(+). The functional protein of Latcripin-3 was expressed in Rosetta-gami (DE3) E. coli, evaluated by Western blotting and mass spectrometry. DPPH testing showed that the protein Latcripin-3 can scavenge free radicals remarkably well. The activity of functional protein Latcripin-3 on A549 cells was studied with flow cytometry and the MTT method. The MTT assay results showed that there was a decreases in cell viability in a dose-dependent and time-dependent manner in protein Latcripin-3 treated groups. Flow cytometry demonstrated that Latcripin-3 can induce apoptosis and block S phase dramatically in human A549 lung cancer cells as compared to the control group. At the same time, the cell ultrastructure observed by transmission electron microscopy supported the results of flow cytometry. This research offers new insights and advantages for identifying anti-oxidant and anti-tumor proteins.

Ammonium Acetate Supplement Strategy for Enhancement of Chaetominine Production in Liquid Culture of Marine-Derived Aspergillus fumigatus CY018

( Chang-qing Liu ),( Xing-chen Wei ),( Fa-liang An ),( Yan-hua Lu ) 한국미생물생명공학회(구 한국산업미생물학회) 2019 Journal of microbiology and biotechnology Vol.29 No.4

Pharmacological research on (CHA), a marine-derived quinazolinone alkaloid with significant cytotoxic activity, is restricted by low yields and is a problem that needs to be settled urgently. In this work, the selection of additional nitrogen sources and the optimization of additional concentrations and longer fermentation times using ammonium acetate, were investigated. CHA production was optimized to 62.1 mg/l with the addition of 50 mM ammonium acetate at 120 h of the fermentation in the shaker flask. This feeding strategy significantly increased 3- deoxy-arabino-heptulosonate-7-phosphate synthase activity and transcript levels of critical genes (laeA, dahp, and trpC) in the shikimate pathway compared with the non-treatment group. In addition, the selection of the feeding rate (0.01 and 0.03 g/l·h) was investigated in a 5-L bioreactor. As a result, CHA production was increased by 57.9 mg/l with a 0.01 g/l·h ammonium acetate feeding rate. This work shows that the strategy of ammonium acetate supplementation had an effective role in improving CHA production by Aspergillus fumigatus CY018. It also shows that this strategy could serve as an important example of large-scale fermentation of a marine fungus in submerged culture.

Relationship between the methylenetetrahydrofolate reductase (MTHFR) rs1801133 SNP and serum homocysteine levels of Zhuang hypertensive patients in the central region of Guangxi

Hu Xi-Jiang,Su Mei-Ru,Cao Bao-Wei,Ou Fa-Bang,Yin Rui-Xing,Luo An-De 대한고혈압학회 2023 Clinical Hypertension Vol.29 No.-

Background The relationship between the methylenetetrahydrofolate reductase (MTHFR) single nucleotide polymorphism (SNP) and serum homocysteine (Hcy) levels or H-type hypertension in different populations is inconsistent. This study aimed to explore the association between the MTHFR rs1801133 SNP and serum Hcy levels of Zhuang hypertensive patients in the central region of Guangxi. Methods A total of 606 Zhuang inpatients with essential hypertension were recruited in our hospital from August 2016 to December 2018. The patients were divided into H-type hypertension (Hcy > 10 μmol/L, n = 528) and non–Htype hypertension (Hcy ≤ 10 μmol/L, n = 78) groups. At the same time, an age- and sex-matched group of 379 subjects with normal physical examination in our hospital were selected as the control group. Blood biochemical measurements and genotyping of the MTHFR rs1801133 SNP were performed. Results The prevalence of H-type hypertension was 87.13%. The levels of serum Hcy in patients with hypertension were higher than those in control group (14.20 ± 5.78 μmol/L vs. 11.97 ± 5.39 μmol/L, P < 0.001), especially in patients with H-type hypertension (15.08 ± 5.65 μmol/L, P < 0.001). The frequencies of TT genotype (22.73%) and T allele (46.21%) in patients with H-type hypertension were significantly higher than those in control group (11.35% and 30.47%, respectively) and non–H-type hypertension group (10.26% and 28.85%, respectively; P < 0.001 for all). Multivariate linear regression analysis showed that serum Hcy levels were significantly correlated with creatinine, lowdensity lipoprotein cholesterol, endogenous creatinine clearance rate, and the MTHFR rs1801133 genotypes in control group, while serum Hcy levels were significantly correlated with creatinine, triglyceride, low-density lipoprotein cholesterol, endogenous creatinine clearance rate, glycosylated hemoglobin, and the MTHFR rs1801133 genotypes in H-type hypertension group (P < 0.05–0.001). Serum Hcy levels in the T allele carriers were higher than those in the T allele noncarriers in both H-type hypertension and control groups. Conclusions There was closely related between the MTHFR rs1801133 SNP and serum Hcy levels in Zhuang patients with H-type hypertension in the central region of Guangxi. The MTHFR SNP may be an important reason for the increase of serum Hcy levels in Zhuang patients with H-type hypertension in this region.