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111.
To develop hydrogenated amorphous carbon (a-C:H) as a biocompatible coating, a-C:H was studied in terms of its protein adsorption during the initial process of cell adsorption. A multilayer surface plasmon resonance (SPR) device consisting of an a-C:H layer on Au was built in the Kretschmann configuration to detect protein adsorption on an a-C:H film surface. From the dependence of reflectivity on the laser incident angle, SPR angle was determined to the incident angle in which the light intensity was reduced drastically. The proteins considered were lysozyme (Lyz) and fibrinogen (Fib). The SPR angle increased from 58.09 to 58.69° upon the adsorption of Lyz when the nonadsorbed Lyz was removed after introduction of 20 μM Lyz-containing solution. Upon the adsorption of Fib, the SPR angle increased from 60.95 to 61.76° when the nonadsorbed Fib were removed after the introduction of 0.4 μM Fib-containing solution. The shift in the SPR angle was small for both cases. Obtained results suggested that the number of adsorbed Lyz was higher than that of adsorbed Fib.  相似文献   
112.
High yield of cell, lipid, and docosahexaenoic acid (DHA) from thraustochytrid strain 12B were achieved without the use of a complex medium and at low NaCl concentration which is detrimental to avoid unnecessary corrosion of steel tank equipment during cultivation. Culture medium that contained only 0.1% NaCl and 1% MgSO4 in an organic base solution containing 8% glucose, 1% yeast extract, and 1% peptone, referred here as NM medium, was found to be as good as or superior to the culture medium prepared from 50%(v/v) seawater with percentage lipid/dry cell weight (DCW) of 66.4%(w/w) and DHA yield up to 43.95 mg/g DCW for the thraustochytrid strain 12B. The NM medium was also applicable to the prominently high DHA-accumulating Schizochytrium limacinum SR21, and therefore this medium could probably be used for other thraustochytrid and other types of microbial strains as well.  相似文献   
113.
Double shielded gas tungsten arc welding (GTAW, also known as tungsten inert gas (TIG) welding) of an SUS304 stainless steel with pure inert argon as the inner layer shielding and the Ar-CO2 or CO2 active gas as the out layer shielding was proposed in this study to investigate its effect on the tungsten electrode protection and the weld shape variation. The experimental results showed that the inner inert argon gas can successfully prevent the outer layer active gas from contacting and oxidizing the tungsten electrode during the welding process. Active gas, carbon dioxide, in the outer layer shielding is decomposed in the arc and dissolves in the liquid pool, which effectively adjusts the active element, oxygen, content in the weld metal. When the weld metal oxygen content is over 70×10-6, the surface-tension induced Marangoni convection changes from outward into inward, and the weld shape varies from a wide shallow one to a narrow deep one. The effect of the inner layer gas flow rate on the weld bead morphology and the weld shape was investigated systematically. The results show that when the flow rate of the inner argon shielding gas is too low, the weld bead is easily oxidized and the weld shape is wide and shallow. A heavy continuous oxide layer on the liquid pool is a barrier to the liquid pool movement.  相似文献   
114.
Porous Titania Ceramic Prepared by Mimicking Silicified Wood   总被引:6,自引:0,他引:6  
A porous titania ceramic with a woodlike microstructure that was analogous to silicified wood was prepared. The production of "titanified wood" was performed using the following process: (i) introduction of titanium tetraisopropoxide into wood materials via vacuum infiltration, (ii) hydrolysis of the titanium tetraisopropoxide in the cell structure to form a titania gel, and (iii) firing at a temperature of 600°–1400°C in air. The resulting titania ceramic had the same external and internal forms of the original wood.  相似文献   
115.
Layout has strong influence on matching properties of a circuit. Current matching models, which characterize both local random non-uniformities and global systematic non-uniformities stochastically, are not adequate for the matching analysis taking the effect of layout realization into account. In order to consider topological information of layout into matching analysis, we propose a matching model which treats the random and systematic components separately. Also, we characterize the micro-loading effect, which modulates fabricated line-width according to the local density of layout patterns, into matching analysis. With these two techniques, we can perform matching analysis of CMOS circuits taking layout information into account.  相似文献   
116.
117.
Developing photoactivatable theranostic platforms with integrated functionalities of biocompatibility, targeting, imaging contrast, and therapy is a promising approach for cancer diagnosis and therapy. Here, we report a theranostic agent based on a hybrid nanoparticle comprising fullerene nanocrystals and gold nanoparticles (FGNPs) for photoacoustic imaging and photothermal therapy. Compared to gold nanoparticles and fullerene crystals, FGNPs exhibited stronger photoacoustic signals and photothermal heating characteristics by irradiating light with an optimal wavelength. Our studies demonstrated that FGNPs could kill cancer cells due to their photothermal heating characteristics in vitro. Moreover, FGNPs that are accumulated in tumor tissue via the enhanced permeation and retention effect can visualize tumor tissue due to their photoacoustic signal in tumor xenograft model mice. The theranostic agent with FGNPs shows promise for cancer therapy.  相似文献   
118.
Artificial supramolecular systems capable of self-assembly and that precisely function in biological media are in high demand. Herein, we demonstrate a highly specific host-guest-pair system that functions in living cells. A per-O-methyl-β-cyclodextrin derivative (R8-B-CDMe) bearing both an octaarginine peptide chain and a BODIPY dye was synthesized as a fluorescent intracellular delivery tool. R8-B-CDMe was efficiently taken up by HeLa cells through both endocytosis and direct transmembrane pathways. R8-B-CDMe formed a 2 : 1 inclusion complex with tetrakis(4-sulfonatophenyl)porphyrin (TPPS) as a guest molecule in water, from which fluorescence resonance energy transfer (FRET) from R8-B-CDMe to TPPS was observed. The FRET phenomenon was clearly detected in living cells using confocal microscopy techniques, which revealed that the formed supramolecular R8-B-CDMe/TPPS complex was maintained within the cells. The R8-B-CDMe cytotoxicity assay revealed that the addition of TPPS counteracts the strong cytotoxicity (IC50=16 μM) of the CD cavity due to complexation within the cells. A series of experiments demonstrated the bio-orthogonality of the supramolecular per-O-methyl-β-CD/tetraarylporphyrin host-guest pair in living cells.  相似文献   
119.
This paper has proposed a parallel-wire driven robot (PWDR) with an active balancer, which is notably useful for such applications as ceiling maintenance and object conveyance near a ceiling in a factory. Because this robot is an under-actuated system, the uncertainty of the inertial parameters of the load strongly affects the resultant motion and reduces the control accuracy because of the dynamics interference. However, to date, the dynamics of this robot has not been thoroughly elucidated. Thus, this study analyzes the dynamics of a PWDR that controls three degree-of-freedom using two wires and an active balancer. Moreover, based on the dynamic analysis, a model-based adaptive controller for the parameter uncertainty of a load is proposed, and its effectiveness is demonstrated through simulation.  相似文献   
120.
PURPOSE: To report a case of severe amebic keratitis in which both Hartmannella and Acanthamoeba were isolated simultaneously from the same lesion. METHOD: Case report. The deep corneal lesion was scraped for cytopathology and isolation of the pathogens. We tested the in vitro sensitivities of the pathogens to several drugs. RESULTS: Cultures of the corneal scrapings and of the solution in the patient's contact lens storage case were positive for Acanthamoeba E9 cysts and trophozoites. Hartmannella ameba coexisted with Acanthamoeba in the cornea. When tested in vitro, Acanthamoeba trophozoites were sensitive to both miconazole nitrate and natamycin, while cysts were sensitive only to natamycin. However, the patient did not respond to these antiamebic drugs. CONCLUSIONS: This case suggests that Acanthamoeba is not the only origin of amebic keratitis. Hartmannella may also cause severe drug-resistant keratitis.  相似文献   
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