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991.
Suzuki K Hiyoshi M Tada H Bando M Ichioka T Kamemura N Kido H 《Analytica chimica acta》2011,(2):321-327
The diagnosis of antibody-mediated allergic disorders is based on clinical findings, skin prick tests and detection of allergen-specific IgE in serum. Here, we present a new microarray technique of high-density antigen immobilization using carboxylated arms on the surface of a diamond-like carbon (DLC)-coated chip. High immobilization capacity of antigen on DLC chip at (0.94–7.82) × 109 molecules mm−2 allowed the analysis of allergen-specific immunoglobulins against not only purified proteins but also natural allergen extracts with wide assay dynamic range. The higher sensitivity of the allergen-specific IgE detection on DLC chip was observed for comparison with the UniCAP system: the DLC chip allowed lowering the limit of dilution rate in UniCAP system to further dilution at 4–8-fold. High correlations (ρ > 0.9–0.85) of allergen-specific IgE values determined by the DLC chip and UniCAP were found in most of 20 different allergens tested. The DLC chip was useful to determine allergen-induced antibodies of IgA, IgG, IgG1, and IgG4 in sera, apart from IgE, as well as secretory IgA in saliva against the same series of allergens on the chip in a minimal amount (1–2 μL) of sample. 相似文献
992.
Kuroyanagi J Kanai K Horiuchi T Takeshita H Kobayashi S Achiwa I Yoshida K Nakamura K Kawakami K 《Chemical & pharmaceutical bulletin》2011,59(3):341-352
A series of 1,3-benzoxazole-4-carbonitriles was synthesized and evaluated for its antifungal activity, solubility, and metabolic stability. Among those compounds, 4-cyano-N,N,5-trimethyl-7-[(3S)-3-methyl-3-(methylamino)pyrrolidin-1-yl]-6-phenyl-1,3-benzoxazole-2-carboxamide (16b) exhibited potent in vitro activity against Candida species, higher water solubility, and improved metabolic stability compared to lead compound 1. Compound 16b showed potent in vivo efficacy against mice Candida infection models and good bioavailability in rats. 相似文献
993.
Julie?LelouvetelEmail author Masashi?Nakagawa Yohei?Sato Koichi?Hishida 《Experiments in fluids》2011,50(4):813-823
A time-resolved particle tracking velocimetry (PTV) system and a shape projection imaging system were used to investigate
the turbulence modifications by bubbles in a downward bubbly flow. Two bubble sizes and three mean void fractions were tested
at a Reynolds number of about 20,000. The strong modifications in the mean velocity, turbulent kinetic energy (TKE) budget,
and velocity spectra are observed in the central region of the pipe that has a high local void fraction. In particular, kinetic
energy production decreased, whereas the TKE dissipation rate increased. This suggests that the transfer of energy due to
bubbles has a very large effect on the TKE budget. Moreover, velocity spectra reveal that the presence of bubbles modifies
the length scales of turbulent eddies, which contain, transfer, and dissipate energy. 相似文献
994.
The singlet gerade states of the hydrogen molecule are strongly affected by the breakdown of the Born-Oppenheimer approximation. This leads to strong non-adiabatic coupling resulting in large changes of the energies and lifetimes of the quantum levels compared to the values obtained in the Born-Oppenheimer or even the adiabatic levels of approximation. The non-adiabatic calculations of Quadrelli, Dressler, and Wolniewicz (1990) [7] (hereinafter QDW) for the three highest vibrational levels (υ = 44, 45, and 46) of the EF 1Σg+ state of D2 predicted an enormous increase of the lifetimes upon excitation of just one quantum of rotational motion. However, although our experimental results for these levels just below the n = 2 dissociation limit do show a strong increase in lifetime, the non-adiabatic lifetimes calculated by QDW are longer than experiment by as much as three orders of magnitude. In their work on isotopomers of hydrogen QDW and Yu and Dressler (1994) [5] published extensive summary tables of ab initio non-adiabatic coupling data. We present a technique which allows us to use their summary data to calculate approximate non-adiabatic ab initio lifetimes. The results reconcile our observed lifetimes with the non-adiabatic coupling from those previous ab initio calculations and also provide a detailed quantitative and qualitative understanding of the unusual rotational dependence of the lifetimes of these very highly excited levels. We also test the current technique by calculating the lifetimes of other levels involved in interactions with these EF levels and by calculating the lifetimes of the EF υ = 33 level of H2, for which no corresponding level exists in the Born-Oppenheimer or adiabatic approximations. 相似文献
995.
Let R k,s(n) denote the number of solutions of the equation \({n= x^2 + y_1^k + y_2^k + \cdots + y_s^k}\) in natural numbers x, y 1, . . . , y s . By a straightforward application of the circle method, an asymptotic formula for R k,s(n) is obtained when k ≥ 3 and s ≥ 2k–1 + 2. When k ≥ 6, work of Heath-Brown and Boklan is applied to establish the asymptotic formula under the milder constraint s ≥ 7 · 2k–4 + 3. Although the principal conclusions provided by Heath-Brown and Boklan are not available for smaller values of k, some of the underlying ideas are still applicable for k = 5, and the main objective of this article is to establish an asymptotic formula for R 5,17(n) by this strategy. 相似文献
996.
Hiroyuki Takano Koichi IzumiyaNaokazu Kumagai Koji Hashimoto 《Applied Surface Science》2011,257(19):8171-8176
The active catalysts for methane formation from the gas mixture of CO2 + 4H2 with almost 100% methane selectivity were prepared by reduction of the oxide mixture of NiO and ZrO2 prepared by calcination of aqueous ZrO2 sol with Sm(NO3)3 and Ni(NO3)2. The 50 at%Ni-50 at%(Zr-Sm oxide) catalyst consisting of 50 at%Ni-50 at%(Zr + Sm) with Zr/Sm = 5 calcined at 650 or 800 °C showed the highest activity for methanation. The active catalysts were Ni supported on tetragonal ZrO2, and the activity for methanation increased by an increase in inclusion of Sm3+ ions substituting Zr4+ ions in the tetragonal ZrO2 lattice as a result of an increase in calcination temperature. However, the increase in calcination temperature decreased BET surface area, metal dispersion and hydrogen uptake due to grain growth. Thus, the optimum calcination temperature existed. 相似文献
997.
998.
Saito N Aoki K Usui Y Shimizu M Hara K Narita N Ogihara N Nakamura K Ishigaki N Kato H Haniu H Taruta S Kim YA Endo M 《Chemical Society reviews》2011,40(7):3824-3834
Carbon fibers are state-of-the-art materials with properties that include being light weight, high strength, and chemically stable, and are applied in various fields including aeronautical science and space science. Investigation of applications of carbon fibers to biomaterials was started 30 or more years ago, and various products have been developed. Because the latest technological progress has realized nano-level control of carbon fibers, applications to biomaterials have also progressed to the age of nano-size. Carbon fibers with diameters in the nano-scale (carbon nanofibers) dramatically improve the functions of conventional biomaterials and make the development of new composite materials possible. Carbon nanofibers also open possibilities for new applications in regenerative medicine and cancer treatment. The first three-dimensional constructions with carbon nanofibers have been realized, and it has been found that the materials could be used as excellent scaffolding for bone tissue regeneration. In this critical review, we summarize the history of carbon fiber application to the biomaterials and describe future perspectives in the new age of nano-level control of carbon fibers (122 references). 相似文献
999.
Gärtner F Boddien A Barsch E Fumino K Losse S Junge H Hollmann D Brückner A Ludwig R Beller M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(23):6425-6436
An extended study of a novel visible-light-driven water reduction system containing an iridium photosensitizer, an in situ iron(0) phosphine water reduction catalyst (WRC), and triethylamine as sacrificial reductant is described. The influences of solvent composition, ligand, ligand-to-metal ratio, and pH were studied. The use of monodentate phosphine ligands led to improved activity of the WRC. By applying a WRC generated in situ from Fe(3) (CO)(12) and tris[3,5-bis(trifluoromethyl)phenyl]phosphine (P[C(6)H(3)(CF(3))(2)](3), Fe(3)(CO)(12)/PR(3)=1:1.5), a catalyst turnover number of more than 1500 was obtained, which constitutes the highest activity reported for any Fe WRC. The maximum incident photon to hydrogen efficiency obtained was 13.4% (440 nm). It is demonstrated that the evolved H(2) flow (0.23 mmol H(2) h(-1) mg(-1) Fe(3)(CO)(12)) is sufficient to be used in polymer electrolyte membrane fuel cells, which generate electricity directly from water with visible light. Mechanistic studies by NMR spectroscopy, in situ IR spectroscopy, and DFT calculations allow for an improved understanding of the mechanism. With respect to the Fe WRC, the complex [HNEt(3)](+)[HFe(3)(CO)(11)](-) was identified as the key intermediate during the catalytic cycle, which led to light-driven hydrogen generation from water. 相似文献
1000.
Shimada T Toyama A Aoki C Aoki Y Tanaka K Sato TA 《Rapid communications in mass spectrometry : RCM》2011,25(23):3521-3526
One-step detection of biological molecules is one of the principal techniques for clinical diagnosis, and the potential of mass spectrometry for biomarker detection has been a promising new approach in the field of medical sciences. We demonstrate here a new and high-sensitivity method that we termed immunobeads-mass spectrometry (iMS), which combines conventional immunoprecipitation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The key feature of iMS is the MS-compatible condition of immunoprecipitation using detergents with a monosaccaride-C8 alkyl chain or a disaccharide-C10 alkyl chain, and the minimized number of steps required for high-sensitivity detection of target peptides in serum or biological fluid. This was achieved by optimizing the wash buffer and subjecting the immunobeads directly to MALDI-TOF MS analysis. Using this method, we showed that 1 fmol of amyloid beta peptide spiked in serum was readily detectable, demonstrating the powerful tool of iMS as a biomarker detection method. 相似文献