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61.
How strong adjuvants such as complete Freund's adjuvant (CFA) promote T cell priming to protein antigens in vivo is still unclear. Since the unmethylated CpG motifs in DNA of bacteria and other nonvertebrates are stimulatory for B cells and antigen-presenting cells, the strong adjuvanticity of CFA could be attributed, at least in part, to the presence of dead bacteria, i.e., a source of stimulatory DNA. In support of this possibility, evidence is presented that insect DNA in mineral oil has even stronger adjuvant activity than CFA by a number of parameters. Synthetic oligodeoxynucleotides (ODNs) containing unmethylated CpG motifs mimic the effects of insect DNA and, even in soluble form, ODNs markedly potentiate clonal expansion of T cell receptor transgenic T cells responding to specific peptide. 相似文献
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64.
The "Sketchphone" is an audiographic communication terminal which makes it possible to transmit handwriting and speech signals simultaneously over a telephone channel. Computer simulation of a voice interleaving technique which causes little degradation in telephone conversation quality was carried out to achieve simultaneous transmission of two signals. A complete "Sketchphone" set has not yet been built, however. A graphic tablet, using a new pressure-conductive rubber sheet, has been developed for this Sketchphone system. Since the rubber sheet is truly pressure sensitive, false signals from the hand or fingers resting on the tablet do not occur. 相似文献
65.
H. Kinoshita T. Yoshizumi M. Osugi J. Kishimoto T. Sugiyama T. Uno T. Watanabe 《Microelectronic Engineering》2009,86(4-6):505-508
We constructed an extreme ultraviolet microscopy (EUVM) system for actinic mask inspection that consists of Schwarzschild optics and an X-ray zooming tube. This system was used to inspect finished extreme ultraviolet lithography (EUVL) masks and Mo/Si glass substrates. A clear EUVM image of a 300-nm-wide pattern on a 6025 glass mask was obtained. The resolution was estimated to be 50 nm or less from this pattern. Programmed phase defects on the glass substrate were also used for inspection. The EUV microscope was able to resolve a programmed pit defect with a width of 40 nm and a depth of 10 nm and also one with a width of 70 nm and a depth of 2 nm. However, a 75-nm-wide 1.5-nm-deep pit defect was not resolved. Thus, in this study, one critical dimension of a pit defect was estimated to be a depth of 2 nm. 相似文献
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67.
Ju-Hyeon Yu Hirotatsu Kishimoto Naofumi Nakazato Joon-Soo Park Akira Kohyama 《Advanced Composite Materials》2018,27(5):531-539
SiC fiber-reinforced SiC matrix (SiC/SiC) composites are expected as a high-temperature structural material for the application of aerospace and nuclear energy system due to their high-temperature stability, reduced-activation property, and excellent irradiation resistance. It was investigated the size effects of test specimen on the fracture behaviour and apparent strength of SiC/SiC tubes in order to minimize the size of test specimen, as well as to develop circumferential tensile test method for SiC/SiC fuel cladding of nuclear reactor. The tube specimens with a narrow width (less than 5 mm) represented the stable value of apparent strength. In case of wide width (>5 mm), the apparent strength of test specimen decreased with the increase in specimen width. It was observed that the fracture of the test specimen with wide width was initiated from the sides of test specimen due to the local contact between loading pin and the test specimen. It is required to use the material with high modulus as a loading pin material in order to avoid the stress concentration caused by local contact. 相似文献
68.
Light reflection at polymer-coated electrodes is studied for polyaniline, poly(o-methylaniline), and poly(o-methoxyaniline). Reflected light intensity is found to be affected greatly by the applied potential for the two reasons: one is absorption of light due to coloring of the oxidized polymer film and the other is light scattering which is concerned with a polymer chain conformation upon oxidation. A new method based on the potential dependence of light reflection is proposed for studying kinetics of conformational changes of polymer chains. The rate constants evaluated are in the range of 0.05-8 s−1 at room temperature, depending on the sort of polymers, the film thickness, and pH of the solution. Irrespective of the sort of polymers, the increase in film thickness or solution pH leads to the decrease of the rate constant. It is found that a film morphology has a significant effect on the rate constant, as confirmed by a comparison of rate constants observed with polyaniline films grown at different rates. 相似文献
69.
Results of bulk viscosity (η) and local viscosity (ξ) of various molecular weights of polystyrene (PS) have been reported. In this paper the relationship between η and bulk diffusion coefficient (DB), and that between ξ and local diffusion coeffizient (DL) are presented. Data obtained lead to several conclusions. From the results of unperturbed dimensions and a universal constant (Φ), it was found that F. Bueche's equation DB · η = const. is valid for polystyrenes with molecular weights over 600. Temperature and component concentration dependence of bulk diffusion coefficient for the two-component blend system may be interpreted in terms of the free volume theory. At an iso-free volume state, molecular weight dependences of bulk diffusion coefficients for both PS of narrow distribution of molecular weight and blend PS can be composed to a single curve, which is composed of two straight lines in a double logarithmic presentation with intersection at Mw = 1.78 × 104 g/mol. The slopes of these two lines were ? 1.0 and ? 3.3, respectively. The product DL · ξ was determined to be 1.10 × 10?7 (c.g.s) for n-paraffines from the data of self-diffusion coefficient and ξ. This made it possible to determine DL from ξ. For higher molecular weights of PS, log DB is a linear function of log Mw while log DL stays almost constant. 相似文献
70.
K Eto Y Tsubamoto Y Terauchi T Sugiyama T Kishimoto N Takahashi N Yamauchi N Kubota S Murayama T Aizawa Y Akanuma S Aizawa H Kasai Y Yazaki T Kadowaki 《Canadian Metallurgical Quarterly》1999,283(5404):981-985
Glucose metabolism in glycolysis and in mitochondria is pivotal to glucose-induced insulin secretion from pancreatic beta cells. One or more factors derived from glycolysis other than pyruvate appear to be required for the generation of mitochondrial signals that lead to insulin secretion. The electrons of the glycolysis-derived reduced form of nicotinamide adenine dinucleotide (NADH) are transferred to mitochondria through the NADH shuttle system. By abolishing the NADH shuttle function, glucose-induced increases in NADH autofluorescence, mitochondrial membrane potential, and adenosine triphosphate content were reduced and glucose-induced insulin secretion was abrogated. The NADH shuttle evidently couples glycolysis with activation of mitochondrial energy metabolism to trigger insulin secretion. 相似文献