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1.
The extraction equilibria of various di- and tripeptides with di-2-ethylhexylphosphoric acid (D2EHPA) were studied at low pH values. The complex extracted to organic phase consisted of one molecule of peptide and two molecules of D2EHPA dimer. The extraction constants of the peptides correlated well with the distribution coefficients of peptides between 1-octanol and water, which is a measure of hydrophobicity. The permeation rates of peptides through an emulsion liquid membrane were examined by using D2EHPA as a carrier, Span 80 as an emulsifier and kerosene as a diluent. The rates varied considerably with peptide type, depending upon the hydrophobicity.  相似文献   
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Directional couplers are successfully fabricated on acrylic substrates using polymers synthesised from deuterated methacrylate and deuterated fluoromethacrylate monomers. The excess loss of a 50 mm long coupler is about 0.7 dB including waveguide and fibre coupling losses. A novel method is proposed for tuning the coupling ratio. By bending the coupler, high precision control of within 1% is attained without optical polarisation dependence.<>  相似文献   
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Abstract— In order to improve the reflective contrast ratio of transflective IPS‐LCDs, a novel pixel design for a normally white reflective IPS has been proposed. In this design, the large‐inter‐electrode‐spacing layout using a novel driving method and a double‐layered electrode have effectively reduced the light leakage. By applying these two technologies, a transflective IPS‐LCD has been successfully demonstrated with a high contrast ratio (15:1) in the reflective mode and a wide‐viewing‐angle characteristic in the transmissive mode.  相似文献   
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Overdose of acetaminophen (APAP), an antipyretic drug, is an important cause of liver injury. However, the mechanism in the rat model remains undetermined. We analyzed APAP-induced hepatotoxicity using rats based on M1/M2-macrophage functions in relation to damage-associated molecular patterns (DAMPs) and autophagy. Liver samples from six-week-old rats injected with APAP (1000 mg/kg BW, ip, once) after 15 h fasting were collected at hour 10, and on days 1, 2, 3, and 5. Liver lesions consisting of coagulation necrosis and inflammation were seen in the affected centrilobular area on days 1 and 2, and then, recovered with reparative fibrosis by day 5. Liver exudative enzymes increased transiently on day 1. CD68+ M1-macrophages increased significantly on days 1 and 2 with increased mRNAs of M1-related cytokines such as IFN-γ and TNF-α, whereas CD163+ M2-macrophages appeared later on days 2 and 3. Macrophages reacting to MHC class II and Iba1 showed M1-type polarization, and CD204+ macrophages tended to be polarized toward M2-type. At hour 10, interestingly, HMGB1 (representative DAMPs) and its related signals, TLR-9 and MyD88, as well as LC3B+ autophagosomes began to increase. Collectively, the pathogenesis of rat APAP hepatotoxicity, which is the first, detailed report for a rat model, might be influenced by macrophage functions of M1 type for tissue injury/inflammation and M2-type for anti-inflammatory/fibrosis; particularly, M1-type may function in relation to DAMPs and autophagy. Understanding the interplayed mechanisms would provide new insight into hepato-pathogenesis and contribute to the possible development of therapeutic strategies.  相似文献   
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In this article, the isothermal flow stress in supercooled austenite was measured for a high hardenability steel. Supercooled austenite forms at the nonequilibrium phase and changes into other phases within a short time. It was confirmed that conventional tensile tests, which require maintaining a constant temperature before stretching, cannot accurately measure the flow stress in supercooled austenite. Therefore, a new tensile test named “the continuous cooling tensile test” was developed. In this test, stretching is conducted during continuous cooling. In the continuous cooling tensile test, the flow stress between 673 K and 973 K (400 °C and 700 °C) was measured. Microscopic observations of the continuous cooling test results verified that the microstructures were supercooled austenite.  相似文献   
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To increase the hyaluronic acid (HA) yield from Streptococcus thermophilus YIT 2084, fermentation conditions (pH, temperature, agitation, aeration) were optimized in milk-based medium, and the effects of supplemental soybean peptides, which have different molecular weight distributions, were determined. HA production was enhanced to approximately 100 mg/l at pH 6.8 and 33–40 °C. Agitation speed and aeration rate slightly affected HA production. Soybean peptides including those of high molecular weight (approximately 27 to 130 kDa) further increased HA production to 208 mg/l under the optimal condition (pH 6.8, 35 °C, 100 rpm), which was 20-fold greater than non-optimal condition. HA production was no longer related to the specific growth rate. The HA produced under the optimal condition included a large amount of high-molecular-weight fraction of 100 to 2000 kDa, compared with under the basal condition without optimization.  相似文献   
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Toluene-tolerant gram-positive bacteria were isolated and identified to belong to the genus Bacillus. They grew in a medium containing yeast extract and in the presence of a separate phase of toluene or other hydrocarbons, but not when aliphatic alcohols were present. The isolate Bacillus cereus R1 did not metabolise or transform toluene. Toluene accumulation in its cells was rapid, unless the organism was supplied with glucose as energy source. In bacteria adapted to toluene, the amount of toluene accumulating in cells was one-half that in nonadapted bacteria. Valinomycin (K+ ionophore) and o-vanadate (ATPase inhibitor) as inhibitors of energy metabolism partly counteracted the effect of glucose as energy source. These results suggest the presence of an efflux mechanism for toluene in strain R1. The nature of this mechanism and its function in a solvent-tolerant gram-positive strain are discussed.  相似文献   
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