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981.
Enzymatic transamidation of gliadins by microbial transglutaminase (mTG) inhibits interferon-γ (IFN-γ) secretion by intestinal T cell lines in patients with celiac disease (CD). To gain insight into the cellular mechanisms underlying the down-regulatory effects of transamidation, we tested a single recombinant α-gliadin (r-gliadin) harbouring two immunodominant peptides, p13 (aa. 120–139) and p23 (aa. 220–239), in HLA-DQ8 transgenic mice, a model of gluten sensitivity. Mice were intranasally immunised with r-gliadin or r-gliadin transamidated by mTG (K-r-gliadin) along with cholera toxin, and the response of mesenteric lymph node cells was analysed by cytokine multiplex assay. An in vitro challenge with r-gliadin was characterised by secretion of specific cytokines featuring both innate immunity and the Th1/Th2/Th17 pattern of the adaptive response. Notably, transamidation specifically down-regulated the Th1 response. Structural studies performed on K-r-gliadin confirmed that specific glutamine residues in p13 and p23, previously found to be deamidated by tissue transglutaminase, were also transamidated by mTG. In silico analysis, simulating p13 and p23 peptide binding to HLA-DQ8 showed that these glutamines, in the form of glutamate, could interact by means of salt bridges with peculiar amino acids of the alpha chain of HLA-DQ8, suggesting that their transamidation may influence the HLA-restricted recognition of these peptides. Thus, the structural findings provided a rationale to explain the down-regulation of the r-gliadin-specific Th1 response following transamidation.  相似文献   
982.
Why should computation be leading to a bifurcation in architectural detailing, resulting in a simultaneous, and opposing, tendency towards either greater precision in fabrication or increasing plasticity? Architectural designer and theorist Peter Macapia asks what is driving these propensities in computation, and what in turn historically might be the relation between the detail and force. What comes into play now, though, when architectural style is no longer identified by a taxonomy of parts, or a vocabulary of orders, but rather by a network of forces and functions correlating actions? How might economic and political power be interacting with force, the diagram and function in contemporary design?  相似文献   
983.
984.
Dense 8YSZ was subjected to pulsed current activated sintering (PCAS) within 1 min of 8YSZ nanopowder preparation using a co-precipitation method. Sintering was accomplished by combining a pulsed current and mechanical pressure. Highly dense 8YSZ with a relative density of up to 99% was produced under simultaneous application of a pressure of 80 MPa and the pulsed current. The effects of the addition of Al2O3 on the sintering behavior, mechanical properties, and ionic conductivities of 8YSZ were investigated.  相似文献   
985.
以氧化锗、次亚磷酸钠、浓盐酸为原料经氧化还原反应合成三氯锗仿,三氯锗仿再与阿魏酸经麦克尔加成反应得到3-三氯锗基-3-(4-羟基-3-甲氧基苯基)丙酸,然后与甲醇钠反应生成3-三甲氧锗基-3-(4-羟基-3-甲氧基苯基)丙酸,再与三乙醇胺发生烷基转移反应生成标题化合物.  相似文献   
986.
A methodology is proposed in this study to investigate the creep properties of porous Ni-8YSZ cermet. Creep experiments have been conducted under reducing atmosphere at the typical SOFC operating temperatures. Specimens have been loaded in a four-point bending test bench. A special attention has been paid in this work to the analytical and numerical modelling of the mechanical test. It has been highlighted that Ni-8YSZ exhibits substantial creep strain rates even at relative low temperatures (700 °C < T < 850 °C). The creep exponent has been found to be just slightly higher than unity (1 < n < 2) while the activation energy has been determined equal to Q = 115 kJ mol−1.High-temperature plastic strains of both Ni and 8YSZ phases have been estimated through the local stress acting on the cermet particles. This analysis indicates that creep behaviour of the Ni-8YSZ composite is not influenced by the metallic phase, but is controlled by the deformation of the 8YSZ matrix. It is also proposed that cermet creep mechanism involves Zr4+cations diffusion at the surface rather than in the bulk of the 8YSZ material.Impact of the Ni-8YSZ cermet creep on the internal stresses distribution in SOFC is discussed considering the anode supported cell (ASC) design. It is shown that cermet creep strain can induce a substantial stress decrease in the thin electrolyte.  相似文献   
987.
基于NCP1014的离线隔离8W反激式恒流LED驱动器,支持DOE能源之星固态照明标准(版面1.1—12/19/08)住宅应用功率因数要求。此类典型的一些产品包括便携式台灯、橱柜等和走廊灯。  相似文献   
988.
[目的]以廉价、易得的原料合成梨小食心虫性信息素(Z/E)-12-十四碳烯醇乙酸酯.[结果]以35.9%的总收率合成了梨小食心虫性信息索(Z/E)-12-十四碳烯醇乙酸酯,GC分析结果表明顺反异构体比例为87/13.将所得的顺反异构体混合物在亚硝酸钠和硝酸体系中经构型转化得到顺反比例为23/77的(Z/E)-12-十四碳烯醇乙酸酯,产物结构经IR、1H NMR等方法确证.[结论]该路线简洁且比大多数文献报道的方法产率略高,值得借鉴.  相似文献   
989.
Microorganisms contaminating aircraft fuel tanks containing jet propellant-8 (JP-8) were isolated and identified by 16S rRNA gene sequencing. Thirty-three samples from six geographically separated airport bases were collected. Two bacterial genera were identified by DNA sequencing including the following isolates: Agrobacterium tumefaciens and Staphylococcus epidermidis. Populations of the above species recovered on culture media ranged from 10 to 103 CFU/ml with Staphylococcus and Agrobacterium being identified in samples taken from more than one airport base. From the bacterial communities isolated and identified in this study, only Staphylococcus was previously reported to thrive in aviation fuel tanks. Changes in aviation fuel composition and/or the ability of certain microbes to grow under certain environmental conditions may account for the isolation of previously undocumented bacterial species in aviation fuel tanks. Restriction fragment length analysis of the PCR-product proved a more reliable, simpler and quicker method to distinguish S. epidermidis and A. tumefaciens than conventional DNA sequencing.  相似文献   
990.
Jinwoo Lee 《Fuel》2011,90(5):1762-1770
An experimental study was carried out to investigate the combustion and emission of JP-8 and diesel fuel in an optically-accessible single-cylinder heavy duty diesel engine equipped with a high pressure common-rail injection system in order to evaluate the feasibility of JP-8 application in diesel engine. The basic spray characteristics, including spray tip penetration and spray angle, were investigated with macroscopic spray images obtained by the Mie-scattering method. The combustion and emission characteristics were analyzed on the basis of the results obtained from the spray experiments. Visualization by direct imaging was used to characterize the combustion process.It was found that JP-8 had a shorter spray tip penetration and wider spray angle than diesel fuel mainly due to the faster vaporization characteristic of JP-8. The peak heat release rate was higher and the premixed burn portion was larger with JP-8 due to its superior mixing rate through faster vaporization characteristics. Furthermore, ignition delay with JP-8 was longer than that with diesel fuel due to the lower cetane number of JP-8. In terms of emission, JP-8 showed a benefit in smoke reduction while it produced larger amounts of HC and NOx. Longer ignition delay and accelerated oxidation in the late stage of JP-8 combustion were verified by direct imaging.  相似文献   
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