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51.
Photodriven DNA strand displacement by using a 2′,6′‐dimethylazobenzene‐tethered strand and poly(l ‐lysine)‐graft‐dextran (PLL‐g‐Dex) as a chaperone is reported. Rapid strand displacement was reversibly induced by UV and visible‐light irradiation without any toehold portion. To further improve the method, the concentration of PLL‐g‐Dex and the number of equivalents of the photoresponsive strand were optimised. Optimally, 64 % strand displacement was reversibly induced by alternating UV and visible‐light irradiation.  相似文献   
52.
The correlation between membrane surface morphology and fuel cell performance was investigated using a series of hydrophilic–hydrophobic multiblock copolymers based on poly(arylene ether sulfone) with different block lengths. The proton conductive regions on the membrane surface were successfully observed by using electrochemical atomic force microscopy (e-AFM). The results revealed a strong dependence of the hydrophilic/hydrophobic microphase-separated structure on the block length. The conductive area ratio (CAR) estimated from the proton conduction image decreased as the block length increased, and it was found to be closely connected with cell resistance that determines fuel cell performance. The well-defined phase-separated structure of multiblock copolymers can improve proton conductivity without any undesirable increments in water uptake or swelling, but in some instances, it affects the interfacial connection with the catalyst layer, resulting in lower fuel cell performance. The results of this study suggest the necessity for further improvement of the membrane morphology by optimizing both the casting conditions and the molecular design of the block sequences.  相似文献   
53.
Granulated metrial gland (GMG) cells are a major immune cell population in the murine pregnant uterus, and contribute to the maintenance of pregnancy by functioning as uterus-specific natural killer (NK) cells. In order to reveal their kinetics, activation, and functional roles in pregnancy, we conducted quantitative and immunohistochemical analyses in normal and immuno-modulator-treated mice. Under a light microscope, GMG cells were identified by red cytoplasmic granules in periodic-acid-Schiff (PAS)-stained sections. They progressively increased in number and size with the peak at day 12-14 of pregnancy in the decidua and metrial gland. New vessel formation was most prominent around day 8, and the total vascular area reached the peak at day 13. GMG cells were often located near the blood vessels, and expressed vascular endothelial growth factor (VEGF), suggesting their possible inducing role in angiogenesis during the development of decidua/metrial gland. While blood vessels in the non-pregnant uterus were negative for vascular cell adhesion molecule (VCAM)-1, those in the pregnant one were positive. Treatment with neutralizing antibody against VCAM-1, however, did not decrease the number of GMG cells. On the other hand, mitosis of GMG cells was frequently observed. These data suggest that the increment of GMG cells during pregnancy may largely result from local proliferation in the uterus rather than an increased influx of precursor cells. Although we attempted to induce in vivo activation of GMG cells by administration of interleukin-12 (IL-12) or alpha-galactosylceramide, a potent activator for natural killer-T (NK-T) cells, the number of GMG cells did not appreciably increase. The present study has demonstrated that GMG cells locally proliferate in the pregnant uterus, not being related to VCAM-1 expression by the uterine vasculature or systemic activation of NK cells and NK-T cells, and seem to be involved in angiogenesis in the pregnant uterus through VEGF production.  相似文献   
54.
The electronic structures of nanometre-sized nickel silicide systems, Ni(2)Si and NiSi, have been studied by energy-loss near-edge structure (ELNES) and first-principles band structure calculations. Experimental ELNES of Ni L(3)- and Si L(2,3)-edges could be explained well using theoretical spectra calculated for the ground state without the core hole, suggesting metallic properties for both silicides. It was shown that a slight difference in ELNES spectra of Ni(2)Si and NiSi comes from the coupling among the Ni d and Si p, d states in the unoccupied bands. The density of states and the contour plots of all the valence electron densities for Ni(2)Si, NiSi together with NiSi(2) show that Ni(2)Si has the bond with the strongest covalent character between Ni and Si atoms and the most transition metal-like character of the Ni 3d band among the three silicides.  相似文献   
55.
The cutting temperature of a cutting tool are required to be low during bone machining for preventing damage to bone cells. However, conventional tools are practically the same as those used for metal cutting, and many operational limitations have been reported. In this study, a dedicated cutting tool was designed for reducing cutting force and temperature. A short contact between the workpiece and the cutting edge leads to a reduction in the cutting force. Furthermore, a straight-line edge improves surface roughness. The effectiveness was evaluated using bovine bone, and the cutting force was found to be decreased by about 40%.  相似文献   
56.
The restoration of innate immune responses has potential as a novel therapeutic strategy for chronic hepatitis C (CHC). We compared the efficacy and safety of induction therapy (IT) with natural interferon-β (n-IFN-β) followed by pegylated-IFN-α/ribavirin (PR) alone (group A, n = 30) and IT with a protease inhibitor (PI) (simeprevir or vaniprevir)/PR (group B, n = 13) in CHC patients with genotype 1b and high viral loads. During IT with nIFN-β, virologic response rates in group A and group B were 10% and 8% (p = 0.6792) at week 4, 30% and 16% (p = 0.6989) at week 12 and 47% and 20% (p = 0.0887) at week 24 respectively. During and after the treatment with PR alone or PI/PR, virologic response rates in groups A and B were 50% and 82% (p = 0.01535) at week 4, 53% and 91% (p = 0.006745) at week 8, 57% and 91% (p = 0.001126) at week 12, 57% and 100% (p < 0.001845) at the end of the treatment and 57% and 80% (p < 0.005166) after treatment cessation. IT with PI/PR linked to the restoration of innate immune response was tolerated well, overcame virological breakthrough, enhanced early virologic responses, and resulted in a sustained virologic response in difficult-to-treat CHC patients. IT with PI/PR is beneficial for treating difficult-to-treat CHC patients.  相似文献   
57.
2‐Arylpyridines, 2‐alkenylpyridine, and aromatic imines can be coupled with aryl bromides in the presence of an iron catalyst, metallic magnesium, a diamine ligand and an organic dihalide oxidant at 0 °C. The use of a 1:1 mixture of tetrahydrofuran and 1,4‐dioxane is essential for this C H bond activation reaction. The reaction has wider scope of the substrate compared with the reaction using a separately prepared Grignard reagent, and proceeds with lower catalyst loading (2.5 mol%).  相似文献   
58.
An analytical study using the nonlinear finite-element method was conducted for reinforced concrete shear wall tests under cyclic loading to estimate the damage from the aspect of energy consumption. First, the validity of the analytical method was confirmed by studying the load–displacement relationship, the condition of the cracking, and a comparison between the total strain energy of the analysis and the loaded energy of the test. Next, the distribution of the energy consumption was investigated, and the division between rebars and concrete was studied. It was determined that energy consumption is an effective method for estimating damage of shear walls.  相似文献   
59.
The redox reaction and the oxidation state of silver in a glass melt were studied by cyclic voltammetry and chronopotentiometry between 800° and 1200°C. Silver ions in glass were reduced at a less noble potential than the rest potential of a platinum electrode. A reversible redox reaction of silver in glass was indicated from the analysis of the cyclic voltammogram. An analysis based on the electron transference number revealed that the solubility of reduced silver increased with increasing temperature. Ag+/Ag0 equilibrium in glass was suggested because the rest potential of the platinum electrode in glass was a mixed potential. No relation was observed between the redox behavior of silver in glass and optical basicity. O-type redox behavior of silver in glass was shown.  相似文献   
60.
Polyimide resists developable with basic aqueous solutions were realized by polyamic acid esters with phenol moieties (PPh's) and naphthoquinone diazides. The polyimide precursors (PPh's) were synthesized from diamines and dicarboxylic acids that have phenol moieties through ester linkage. A selective reaction of alcohol groups with acid dianhydride groups made the synthesis of the PPh's possible, even if the phenol groups were in the reaction mixtures. The PPh's were soluble in basic aqueous developer, but their dissolution rates were too low for use as resists. To increase the resist dissolution rate, polyamic acids were added to the PPh's. By adjusting the dissolution rates in basic aqueous developers, fine patterns could be realized. The polyimide resists had high thermal stability and reliable adhesive property to silicon substrate. © 1994 John Wiley & Sons, Inc.  相似文献   
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