Theoretical research and experimental study for a new measurement method of standing wave levitation force

Xinbo Li,Hai Jiang,Xiaoyang Jiao,Kai Zhang,Guojun Liu,Jian-Fang Liu 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.5

Based on the lever principle, a novel measurement method for the standing wave levitation force is investigated and the measurementdevice is developed. The relative levitation force was simulated by MATLAB software, from which the relative levitation force distributionand the curves of relative levitation force in vertical and horizontal directions were obtained. To verify the rationale of the measurementmethod, a series of experiments were carried out with the designed measurement device system. The levitation force distributionand the curves of levitation force in vertical and horizontal directions were also obtained from the experiment. Comparing the experimentalresults with the simulation, the levitation force distribution situation from the experimental results and the simulation is identical.

Dexamethasone enhances glucose uptake by SGLT1 and GLUT1 and boosts ATP generation through the PPP-TCA cycle in bovine neutrophils

Xinbo Wang,Mingyu Tang,Yuming Zhang,Yansong Li,Jingdong Mao,Qinghua Deng,Shusen Li,Zhenwei Jia,Liyin Du 대한수의학회 2022 Journal of Veterinary Science Vol.23 No.5

Background: Clinical dexamethasone (DEX) treatment or stress in bovines results in extensive physiological changes with prominent hyperglycemia and neutrophils dysfunction. Objectives: To elucidate the effects of DEX treatment in vivo on cellular energy status and the underlying mechanism in circulating neutrophils. Methods: We selected eight-month-old male bovines and injected DEX for 3 consecutive days (1 time/d). The levels of glucose, total protein (TP), total cholesterol (TC), and the proinflammatory cytokines interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α in blood were examined, and we then detected glycogen and adenosine triphosphate (ATP) content, phosphofructosekinase-1 (PFK1) and glucose-6-phosphate dehydrogenase (G6PDH) activity, glucose transporter (GLUT)1, GLUT4, sodium/glucose cotransporter (SGLT)1 and citrate synthase (CS) protein expression and autophagy levels in circulating neutrophils. Results: DEX injection markedly increased blood glucose, TP and TC levels, the Ca2+/P5+ ratio and the neutrophil/lymphocyte ratio and significantly decreased blood IL-1β, IL-6 and TNF-α levels. Particularly in neutrophils, DEX injection inhibited p65-NFκB activation and elevated glycogen and ATP contents and SGLT1, GLUT1 and GR expression while inhibiting PFK1 activity, enhancing G6PDH activity and CS expression and lowering cell autophagy levels. Conclusions: DEX induced neutrophils glucose uptake by enhancing SGLT1 and GLUT1 expression and the transformation of energy metabolism from glycolysis to pentose phosphate pathway (PPP)-tricarboxylic acid (TCA) cycle. This finding gives us a new perspective on deeper understanding of clinical anti-inflammatory effects of DEX on bovine.

The anti-tumor efficacy of 20(S)-protopanaxadiol, an active metabolite of ginseng, according to fasting on hepatocellular carcinoma

Wenzhen Li,YifanWang,Xinbo Zhou,Xiaohong Pan,Junhong Lu,Hongliu Sun,Zeping Xie,Shayan Chen,Xue Gao 고려인삼학회 2022 Journal of Ginseng Research Vol.46 No.1

Background: 20(S)-protopanaxadiol (20(S)-PPD), one of the main active metabolites of ginseng, performs a broad spectrum of anti-tumor effects. Our aims are to search out new strategies to enhance anti-tumor effects of natural products, including 20(S)-PPD. In recent years, fasting has been shown to be multifunctional on tumor progression. Here, the effects of fasting combined with 20(S)-PPD on hepatocellular carcinoma growth, apoptosis, migration, invasion and cell cycle were explored. Methods: CCK-8 assay, trypan blue dye exclusion test, imagings photographed by HoloMonitorTM M4, transwell assay and flow cytometry assay were performed for functional analyses on cell proliferation, morphology, migration, invasion, apoptosis, necrosis and cell cycle. The expressions of genes on protein levels were tested by western blot. Tumor-bearing mice were used to evaluate the effects of intermittent fasting combined with 20(S)-PPD. Results: We firstly confirmed that fasting-mimicking increased the anti-proliferation effect of 20(S)-PPD in human HepG2 cells in vitro. In fasting-mimicking culturing medium, the apoptosis and necrosis induced by 20(S)-PPD increased and more cells were arrested at G0-G1 phase. Meanwhile, invasion and migration of cells were decreased by down-regulating the expressions of matrix metalloproteinase (MMP)-2 and MMP-9 in fasting-mimicking medium. Furthermore, the in vivo study confirmed that intermittent fasting enhanced the tumor growth inhibition of 20(S)-PPD in H22 tumor-bearing mice without obvious side effects. Conclusion: Fasting significantly sensitized HCC cells to 20(S)-PPD in vivo and in vitro. These data indicated that dietary restriction can be one of the potential strategies of chinese medicine or its active metabolites against hepatocellular carcinoma.

Effect of teeth bending and mushrooming damages on leakage performance of a labyrinth seal

Xin Yan,Xinbo Dai,Kang Zhang,Jun Li,Kun He 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

To achieve higher aerodynamic performance, turbine usually works at tight clearance, which results in inevitable rub between the rotor and stator parts of labyrinth seal due to vibrations, misalignment, mechanical force, thermal stress, etc. In the rubbing events, contact between labyrinth fin and rotor part will commonly induce the teeth bending and mushrooming damages, which significantly affect the discharge performance of a labyrinth seal. To account for the influence of teeth bending and mushrooming on leakage performance of a straight-through labyrinth seal, the leakage rates and flow fields in the worn labyrinth seal are measured and also compared with the original design cases. With numerical methods, the discharge behaviors of the labyrinth seal with different degrees of bending and mushroom damages are analyzed. It shows that the predicted leakage performance and flow fields in the labyrinth seals match well with the experimental tests. For the bending cases, the leakage rates and flow patterns in labyrinth seals are dependent on the effective clearance and bending angle. The leakage ratio of forward bending case is smaller than that of backward bending case with the same geometrical dimensions. However, for the mushroomed labyrinth seals, the leakage rates and flow patterns are much dependent on the effective clearance but slightly dependent on the mushroom radius.

Effect of fermented blueberry on the oxidative stability and volatile molecule profiles of emulsion-type sausage during refrigerated storage

Zhou, Hengyue,Zhuang, Xinbo,Zhou, Changyu,Ding, Daming,Li, Chunbao,Bai, Yun,Zhou, Guanghong Asian Australasian Association of Animal Productio 2020 Animal Bioscience Vol.33 No.5

Objective: The aim of this work was to assess the effect of fermented blueberry (FB; 2%, 4%, and 6%) on the oxidative stability and volatile molecule profiles of emulsion-type sausage stored at 4℃ for 28 days. Methods: The antioxidant activity of FB was determined through radical-scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radicals. Four formulations of sausage treatments with different FB levels (0%, 2%, 4%, 6%) were prepared, then peroxide value (POVs), thiobarbituric acid-reactive substances (TBARS) values, protein carbonyls and thiol groups were measured. The aroma profiles of sausages for each treatment was also determined. Results: The half maximal inhibitory concentration indicated that FB had greater scavenging ability than ascorbic acid against DPPH and hydroxyl radicals. Sausages with FB significantly retarded increases in POVs and TBARS, as well as in the content of protein carbonyls during all storage days (p<0.05). Particularly, 4% and 6% FB-treated sausages had better oxidation inhibition effects. However, FB accelerated the reduction in thiol groups (p<0.05). Additionally, FB inhibits the excessive formation of aldehyde compounds; for example, hexanal, which may cause rancid flavors, decreased from 58.25% to 19.41%. FB also created 6 alcohols (i.e., 2-methyl-1-propanol, 3-methyl-1-butanol, and phenylethyl alcohol), 5 ester compounds (i.e., ethyl acetate, ethyl lactate, and ethyl hexanoate) and 3-hydroxy-2-butanone in the sausages that contribute to sausage flavors. The principal component analysis showed that the aroma profiles of sausages with and without FB are easily identified. Conclusion: The addition of FB could significantly reduce the lipid and protein oxidation and improve oxidative stability for storage. Also, adding FB could inhibit rancid flavors and contribute to sausage flavors.

Controllable Synthesis of Silver Nanoparticles Using Piezoelectric-Actuated High-Frequency Vibration Self-Circulating Microfluidic Reactor

Guojun Liu,Fang He,Yan Li,Xinbo Li,Hong Zhao,Conghui Wang,Conghong Zhan,Chunxiu Tang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.8

Based on the liquid-phase reduction mechanism, a controllable synthesis method, which uses piezoelectric-actuated high-frequency vibration self-circulating microfluidic reactor, to prepare silver nanoparticles is proposed. Firstly, the synthesis mechanism of silver nanoparticles and the working principle of the microfluidic reactor were analyzed. Then, in order to study and explore the influence of self-circulating and high frequency vibration on the synthesis of silver nanoparticles, a series of related synthesis experiments were carried out. The synthesized silver nanoparticles were characterized by UV-Visible spectroscopy and transmission electron microscopy. The effects of micropump driving voltage and high-frequency vibration on the synthesis of silver nanoparticles were analyzed. The experiment results show that when the silver nanoparticles were synthesized using piezoelectric-actuated high-frequency vibration self-circulating microfluidic reactor, the higher the driving voltage of the circulating reflux micropump, the faster the vortex rotation speed in the mixing pool and the more uniform the reagent reaction. Besides, high-frequency vibration can suppress the aggregation of silver nanoparticles, and balance the growth environment of particles, which is beneficial to the formation of silver nanoparticles with good monodispersity, high sphericity and small size deviation.