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排序方式: 共有419条查询结果,搜索用时 171 毫秒
61.
Matsumoto N Ando T Inoue T Ohtake Y Fukuchi N Hara T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2008,25(7):1642-1651
We report on the high-quality holographic generation of higher-order Laguerre-Gaussian (LG) beams using a liquid-crystal-on-silicon spatial light modulator. The effects of the input beam pattern on the output LG beam quality are investigated in detail through theoretical discussions and experiments. Correlation analyses between observed beam patterns and theoretical mode profiles reveal that higher beam quality is achieved for output LG beams generated from a top-hat input beam than from a Gaussian input beam. 相似文献
62.
Henares TG Takaishi M Yoshida N Terabe S Mizutani F Sekizawa R Hisamoto H 《Analytical chemistry》2007,79(3):908-915
A general and simple implementation of simultaneous multiparametric sensing in a single microchip is presented by using a capillary-assembled microchip (CAs-CHIP) integrated with the plural different reagent-release capillaries (RRCs), acting as various biochemical sensors. A novel "drop-and-sip" technique of fluid handling is performed with a microliter droplet of a model sample solution containing proteases (trypsin, chymotrypsin, thrombin, elastase) and divalent cations (Ca2+, Zn2+, Mg2+) that passes through the microchannel with the aid of a micropipette as a vacuum pump, concurrently filling each RRC via capillary force. To avert the evaporation of the nanoliter sample volume in each capillary, PDMS oil is dropped on the outlet hole of the CAs-CHIP exploiting the capillary force that results in spontaneous sealing of all the RRCs. In addition, this high-speed sample introduction alleviates the possibility of protein adsorption and capillary cross-contamination, allowing a reliable and multianalyte determination of a sample containing many different proteases and divalent cations by using the fluorescence image analysis. Presented results suggested the possible application of this microchip in the field of drug discovery and systems biology. 相似文献
63.
The least detectable concentration (LDC) and dynamic range (DR) of three immunoassay systems are compared using four distinct antibodies (all specific for estradiol but with different affinities) on each system. The systems evaluated include the industry standard, ELISA, and two biosensors, surface plasmon resonance and kinetic exclusion. In all cases, the measurements of inhibition curves (response vs estradiol concentration) were contracted to outside experts (the biosensor manufacturers themselves in the case of the biosensors), each of whom was supplied with the same blind samples. Each biosensor manufacturer also reported an estimate of the equilibrium dissociation constant (Kd) for each of the antibodies. The LDC and DR observed for the kinetic exclusion biosensor are consistent with an interpretation of Kd limited detection while that from the other biosensor and ELISA show limits of detection somewhat above those expected for Kd limited performance. The determined LDC and DR of each biosensor is self-consistent in the sense that none of the inhibition data contradicts theoretical limits associated with the Kd as measured on that system; however, some contradictions are apparent across platforms. The use of multiple antibodies of differing Kd improves confidence that the observed differences in performance are associated with the immunoassay system rather than the particular analyte. 相似文献
64.
Abe Yasunori Semboshi Satoshi Masahashi Naoya Lim Sung Hwan Choi Eun-Ae Han Seung Zeon 《Metallurgical and Materials Transactions A》2023,54(3):928-938
Metallurgical and Materials Transactions A - Conductive spring wires for application in electrical components require high strength, high electrical conductivity, and convenient manufacturability.... 相似文献
65.
Kazuhiro Hirano Hideki Yamauchi Naoya Nakahara Kazuo Kinoshita Maki Yamaguchi Shigeru Takemori 《International journal of molecular sciences》2021,22(23)
We performed X-ray diffraction analyses on rat plantaris muscle to determine if there are strain-specific structural changes at the molecular level after eccentric contraction (ECC). ECC was elicited in situ by supramaximal electrical stimulation through the tibial nerve. One hour after a series of ECC sessions, the structural changes that remained in the sarcomere were evaluated using X-ray diffraction. Proteins involved in cell signaling pathways in the muscle were also examined. ECC elicited by 100, 75, and 50 Hz stimulation respectively developed peak tension of 1.34, 1.12 and 0.79 times the isometric maximal tetanus tension. The series of ECC sessions phosphorylated the forkhead box O proteins (FoxO) in a tension-time integral-dependent manner, as well as phosphorylated the mitogen-activated protein kinases (MAPK) and a protein in the mammalian target of rapamycin (mTOR) pathway in a maximal tension dependent manner. Compared to isometric contractions, ECC was more efficient in phosphorylating the signaling proteins. X-ray diffraction revealed that the myofilament lattice was preserved even after intense ECC stimulation at 100 Hz. Additionally, ECC < 75 Hz preserved the molecular alignment of myoproteins along the myofilaments, while 75-Hz stimulation induced a slight but significant decrease in the intensity of meridional troponin reflection at 1/38 nm−1, and of myosin reflection at 1/14.4 nm−1. These two reflections demonstrated no appreciable decrease with triple repetitions of the standard series of ECC sessions at 50 Hz, suggesting that the intensity decrease depended on the instantaneous maximal tension development rather than the total load of contraction, and was more likely linked with the phosphorylation of MAPK and mTOR signaling proteins. 相似文献
66.
Glass TR Ohmura N Morita K Sasaki K Saiki H Takagi Y Kataoka C Ando A 《Analytical chemistry》2006,78(20):7240-7247
Immunoassays for detection of a class of closely related antigens, e.g., PCBs, have often been too specific (responding strongly to some members of the class and missing others) and no general method for adjusting the response has been described. In this paper, the difference in the response of a model immunoassay to different Kanechlors (Japanese commercial mixtures of PCBs, analogous to Aroclors in the United States) is reduced from 20- or 50-fold (depending on which antibody is used) to 3-fold when the antibodies are mixed at the proper ratio. A mathematical model based on competitive binding of two antibodies for up to four antigens has been developed and used to describe the assay performance and to predict optimum mix ratios for the antibodies used. The model (based on separate measurement of each antibody's effective Kd for each Kanechlor) provides an excellent fit to the measured mixed antibody assay response. The model is also successful in identifying cases where mixing monoclonal antibodies will not improve the response. It is thought the method described will have applicability in a variety of cases where the analytical goal is semiquantitative screening based on the total quantity of an unknown mixture of related compounds. 相似文献
67.
Yamamoto A Kakutani N Yamamoto K Kamiura T Miyakoda H 《Environmental science & technology》2006,40(13):4132-4137
A highly sensitive and uncomplicated method of analyzing steroidal hormones in river and estuarine water samples was developed using a liquid chromatography tandem mass spectrometer equipped with an electrospray ionization (ESI) source and atmospheric pressure photoionization (APPI) source. Steroidal hormones included not only estrogen but also androgen and conjugates of these two. APPI displayed greater sensitivity than ESI for most of the unconjugated steroids examined, with very high sensitivity for testosterone and 4-androstene-3,17-dione in particular. For conjugated hormones, in contrast, ESI was more effective. The method developed was applied to the determination of hormones in the rivers of Osaka City and their estuaries, where the hormones detected were affected by the effluent from municipal wastewater treatment plants (WWTPs), and hormone concentration values were comparable to those reported in previous studies of such effluent. Because of the two-way flow and stagnancy of streams and watercourses, continuous input of steroidal hormones from WWTPs seems to bring about local accumulation. Levels of androgen were 1 order of magnitude lower than those of estrogen. Estrone, estrone 3-sulfate, and 4-androstene-3,17-dione were detected in almost all water samples, with maxima of 51, 5.1, and 6.4 ng L(-1), respectively. 相似文献
68.
Mitamura K Imae T Mouri E Torikai N Matsuoka H Nakamura T 《Journal of nanoscience and nanotechnology》2006,6(1):36-42
Hybrid Langmuir and Langmuir-Blodgett monolayers of a perfluorooctadecanoic acid mixed with a rigid block copolymer, poly(3,5-bis(3,5-bis(benzyloxy)benzyloxy)benzyl methacrylate-randommethacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), which is composed of benzyloxy dendron side chains and perfluorinated side chains, were prepared and characterized by surface pressure-surface area isotherms, atomic force microscopic images and neutron and X-ray reflectometries. The two-dimensionally phase-separated structures of monolayer films and their morphologies with plateau and terrace were confirmed. The monolayers were separated into a dendron layer, a perfluorinated layer, and a carboxyl layer. The layer formation is originated not only in the intermolecular interaction between a perfluorooctadecanoic acid and a block copolymer but also in the geometry of the molecules. Especially, the amphiphilicity of perfluorinated surfactant plays a role to the ordered array of the block copolymers. 相似文献
69.
We examined muscle spindles in the posterior cricoarytenoid (PCA) muscle of the marmoset. The spindle capsule contained only one intrafusal muscle fiber which did not form a typical aggregation of equatorial nuclei such as bags and chains. The intrafusal fiber was innervated by sensory endings which branched and arranged irregularly. These sensory endings lay on the surface of the fiber in shallow grooves or deeply penetrated into it. These findings suggest that the muscle spindles in the marmoset PCA muscle are strikingly different in the structure of intrafusal fibers in the arrangement of sensory endings from those in common mammalian skeletal muscles. 相似文献
70.
Finite-difference time-domain (FDTD) analysis has been used to predict the time-resolved reflectance from multilayered slabs with a nonscattering layer. Light propagation across the nonscattering layer was calculated based on the light intensity characteristics along a ray in free space. Additional equivalent source functions due to light from scattering regions across the nonscattering region were introduced into the diffusion equation and an additional set of the diffusion equation was solved by FDTD analysis by employing new boundary conditions. The formulation was used to calculate time-resolved reflectances of three- and four-layered slabs containing a nonscattering layer. The received light intensity and the mean time of flight estimated from the time-resolved reflectance are in reasonable agreement with previously reported experimental data and Monte Carlo simulations. 相似文献