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121.
Myeong Seong Sim Hye Jeong Kim Sang Hee Jo Chun Kim Il Yup Chung 《International journal of molecular sciences》2022,23(7)
Lysophosphatidylserine (LysoPS) is an amphipathic lysophospholipid that mediates a broad spectrum of inflammatory responses through a poorly characterized mechanism. Because LysoPS levels can rise in a variety of pathological conditions, we sought to investigate LysoPS’s potential role in airway epithelial cells that actively participate in lung homeostasis. Here, we report a previously unappreciated function of LysoPS in production of a mucin component, MUC5AC, in the airway epithelial cells. LysoPS stimulated lung epithelial cells to produce MUC5AC via signaling pathways involving TACE, EGFR, and ERK. Specifically, LysoPS- dependent biphasic activation of ERK resulted in TGF-α secretion and strong EGFR phosphorylation leading to MUC5AC production. Collectively, LysoPS induces the expression of MUC5AC via a feedback loop composed of proligand synthesis and its proteolysis by TACE and following autocrine EGFR activation. To our surprise, we were not able to find a role of GPCRs and TLR2, known LyoPS receptors in LysoPS-induced MUC5AC production in airway epithelial cells, suggesting a potential receptor-independent action of LysoPS during inflammation. This study provides new insight into the potential function and mechanism of LysoPS as an emerging lipid mediator in airway inflammation. 相似文献
122.
Seong Jin Park Kristina Cowan John L. Johnson Randall M. German 《International Journal of Refractory Metals and Hard Materials》2008,26(3):152-163
Development of nanograined WC–Co presents challenges for grain size measurement. In this study, standard and nanocrystalline WC–Co powders are processed by conventional and spark sintering. The resulting microstructures are characterized by image analysis of scanning electron microscopy micrographs, X-ray line broadening, and magnetic coercivity. The results are analyzed and a property map relating coercivity to WC grain size is developed. Equations for interface-controlled grain growth are transformed into the master sintering curve form and are used to analyze the grain size data from the three measurement techniques. 相似文献
123.
Next‐Generation Sequencing Analyses of Bacterial Community Structures in Soybean Pastes Produced in Northeast China
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Mi‐Hwa Lee Fan‐Zhu Li Jiyeon Lee Jisu Kang Seong‐Il Lim Young‐Do Nam 《Journal of food science》2017,82(4):960-968
Fermented soybean foods contain nutritional components including easily digestible peptides, cholesterol‐free oils, minerals, and vitamins. Various fermented soybean foods have been developed and are consumed as flavoring condiments in Asian regions. While the quality of fermented soybean foods is largely affected by microorganisms that participate in the fermentation process, our knowledge about the microorganisms in soybean pastes manufactured in Northeast China is limited. The current study used a culture‐independent barcoded pyrosequencing method targeting hypervariable V1/V2 regions of the 16S rRNA gene to evaluate Korean doenjang and soybean pastes prepared by the Hun Chinese (SPHC) and Korean minority (SPKM) populations in Northeast China. In total, 63399 high‐quality sequences were derived from 16 soybean paste samples collected in Northeast China. Each bacterial species‐level taxon of SPHC, SPKM, and Korean doenjang was clustered separately. Each paste contained representative bacterial species that could be distinguished from each other: Bacillus subtilis in SPKM, Tetragenococcus halophilus in SPHC, and Enterococcus durans in Korean doenjang. This is the 1st massive sequencing‐based study analyzing microbial communities in soybean pastes manufactured in Northeast China, compared to Korean doenjang. Our results clearly showed that each soybean paste contained unique microbial communities that varied depending on the manufacturing process and location. 相似文献
124.
Effect of Amine Additive for the Synthesis of Cadmium Selenide Quantum Dots in a Microreactor
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![点击此处可从《International Journal of Applied Ceramic Technology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Da‐Woon Jeong Basudev Swain Tae‐Yeon Seong Kyoung‐Tae Park Chan Gi Lee Bum Sung Kim 《International Journal of Applied Ceramic Technology》2016,13(2):223-227
The effect of octylamine flow rate on the structure and morphology of CdSe quantum dots synthesized in a microreactor was studied. The flow rate of octylamine was varied from 0.005 ml/min to 0.030 ml/min, and the optical properties of the synthesized particles were analyzed by UV–vis and photoluminescence spectroscopy. The particle size of the quantum dots was found to increase with an increasing octylamine flow rate. Further, UV–vis and photoluminescence bands were found to be red‐shifted with an increasing flow rate. We determined that, by controlling octylamine flow rate, the particle size of the quantum dots could be controlled. This method will help to determine the optimal octylamine flow conditions for synthesizing nanoparticles for use in a diverse range of applications. 相似文献
125.
The effect of coal size (0.73–1.03 mm), excess air ratio (1.0–1.4), operating bed temperature (750–900‡C), coal feeding rate
(1–3 kg/h), and coal recycle rate (20–40 kg/h) on combustion efficiency, temperature profiles along the bed height and flue
gas composition have been determined in a bubbling and circulating fluidized bed combustor (7.8 cm-ID x 2.6 m-high).
Combustion efficiency increases with increasing excess air ratio and operating bed temperature and it decreases with increasing
particle size in the bubbling and circulating fluidzing beds. In general, temperature profiles and combustion efficiency are
more uniform and higher in a circulating bed than those in bubbling bed. Combustion efficiency also increases with increasing
recycle rate of unburned coal in the circulating bed.
The ratio of CO/CO2 of flue gas decreases with increasing bed temperature and excess air ratio, whereas the ratio of O2(CO + CO2) decreases with bed temperature in both bubbling and circulating fluidized beds. 相似文献
126.
Su-Gwang Jeong Seong Jin Chang Seunghwan Wi Yujin Kang Hwayoung Lee 《Journal of Adhesion Science and Technology》2013,27(3):297-309
Latent heat thermal energy storage using phase change materials (PCMs) is considered to be the method with the most potential to solve the energy shortage problem. In this study, paraffin-based mixed shape-stabilized PCM (SSPCM) (PBMS) was made by vacuum impregnation method. The prepared PBMS was added to gypsum powder as a fine aggregate. In the experiment, the n-hexadecane and n-octadecane was used as the PCM and the materials have latent heat capacities of 254.7 and 247.6 J/g, and melting points of 20.84 and 30.4 °C, respectively. The PBMS was prepared by an impregnation method in a vacuum, following the manufacturing process. The physical and thermal properties of the PBMS gypsum board were analyzed by Fourier transform infrared spectrometry (FTIS), differential scanning calorimetry, enthalpy analysis, and thermogravimetric analysis. From the Fourier transform infrared analysis, PBMS could be maintained in the structure of the gypsum board due to its physical rather than chemical bonding. From the specific heat and enthalpy analysis, the PBMS has high enthalpy and thermal inertia property. In addition, the gypsum board with PBMS has high latent heat capacity and high thermal efficiency. 相似文献
127.
Polyvinylidene fluoride (PVDF)‐based nanofiber was successfully produced for a high performance and stable humidity sensor via a solution‐blowing spinning method. The performances of the manufactured sensors, including the impedance change with relative humidity (RH), moisture stability, and response and recovery times, were investigated. To improve charge carrier transfer, which is the main mechanism of humidity sensing, especially under low RH conditions, lithium chloride was used and displayed the best linearity in the impedance change with RH. Fast response and recovery times of 1.7 and 16.1 s were, respectively, achieved with zinc oxide nanoparticles. Furthermore, the sensors showed excellent moisture stability, owing to the hydrophobicity of PVDF, and this was demonstrated via repeatability testing and scanning electron microscopy. The humidity sensing mechanism was discussed using complex impedance spectra. POLYM. ENG. SCI., 59:304–310, 2019. © 2018 Society of Plastics Engineers 相似文献
128.
Donghyun Kang Joobeom Seo So Young Lee Jai Young Lee Kyu Seong Choi Shim Sung Lee 《Inorganic chemistry communications》2007,10(12):1425-1428
A new dicadmium(II) complex [Cd2(L)2(H2O)2](NO3)4 · 8H2O (1) with the tripodal amide ligand L (tris[3-aza-2-oxo-4-(2-pyridyl)butyl]amine) was synthesized and structurally characterized. Complex 1 is revealed as a dinuclear 2:2 (Cd:L) complex, in which each cadmium(II) ion is hepta-coordinated with the coordination surrounding of distorted monocapped octahedral geometry. Two cadmium(II) ions are dibridged by two carbonyl μ-O atoms forming a Cd2(μ-O)2 parallelogram-type moiety. Interestingly, the dinuclear coordination sphere can be seen as resulting from the fusion of two distorted monocapped octahedral [Cd(L)(H2O)]2+ units through sharing one edge originated from the two carbonyl μ-O atoms as a first example. Comparative NMR, IR and FAB-mass data of 1 are also discussed. 相似文献
129.
Polymer electrolytes based on a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresins with lithium salt and plasticizer were prepared with an in situ blending process to improve both the mechanical properties and the ionic conductivity (σ). The PEG/lithium perchlorate (LiClO4) complexes, including blends of cyanoethyl pullulan (CRS) and cyanoethyl poly(vinyl alcohol) (CRV), exhibited higher σ's than a simple PEG/LiClO4 complex when the blend compositions of CRS/CRV were 5 : 5 or 3 : 7 or than CRV alone. When the CRS/CRV blend was compared with a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) (CRM) in the same molar ratio, the σ values of the polymer electrolytes containing the CRM copolymer series were slightly higher than those of the CRS/CRV blends containing PEG/LiClO4 complexes. Moreover, the addition of cyanoresin to PEG/LiClO4/(ethylene carbonate–propylene carbonate) polymer electrolytes provided better thermal stability and dynamic mechanical properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2402–2408, 2007 相似文献
130.
Ln2B2O7 (Ln=Sm, Eu, Gd and Tb; B=Zr or Ti) with pyrochlore structure was prepared by sol–gel method for the high-temperature catalytic combustion. The crystal structure of Ln2B2O7 was identified by XRD and their surface area was about 4 m2/g after calcinations at 1200 °C. Catalytic activity of methane combustion was observed for Ln2Zr2O7 series and the best catalyst was Sm2Zr2O7. Its relative reaction rate per unit surface area at 600 °C was 2 cm3/m2 min, which was twice higher than that of Mn-substituted Sr hexaaluminate. From surface analysis by XPS, the low binding energy of each Ln element of Ln2Zr2O7 compared to that of Ln2Ti2O7, gave the catalytic activity of methane combustion. 相似文献