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61.
Naruse M Miyazaki T Kubota F Kawazoe T Kobayashi K Sangu S Ohtsu M 《Optics letters》2005,30(2):201-203
A nanoscale data summation architecture is proposed and experimentally demonstrated based on the optical near-field interaction between quantum dots. Based on local electromagnetic interactions between a few nanometric elements via optical near fields, we can combine multiple excitations at a certain quantum dot, which allows construction of a summation architecture. Summation plays a key role for content-addressable memory, which is one of the most important functions in optical networks. 相似文献
62.
Suzuki Masayasu Watamabe Nobuyuki Tamiya Eiichi Kataoka Tetsuro Tokunaga Tohru Karube Isao 《Applied biochemistry and biotechnology》1987,15(3):191-200
A novel tumor-detection system consisting of complementmediated cytolytic reaction and an image processing system was developed
for the simple and rapid determination of tumor cells.
The present system consists of a CCD image sensor, image memory board, personal computer, and microscope.
When monoclonal antibody 3C4, which is specific to the guinea pig hepatoma L-10, was added to cell suspension, only L-10 cytolysis
occurred. Cytolysis caused a decrease in brightness of the cells observed by phase-contrast microscopy. The phase contrast
image of the cells before cytolysis was converted to a digitalized signal and stored in computer memory. After cytolysis,
a brightness threshold above that of lysed cells was subtracted from the digitalized signal and compared to the signal stored
before reaction.
L-10 cells in mixed cell suspension were determined specifically by the system. Measurement time was only 2 sec and overall
time, including reaction time, was approximately 30 min. Since this method does not require a cell washing process, automation
of the whole system is possible. 相似文献
63.
Direct Observation of Ordered High‐Spin–Low‐Spin Intermediate States of an Iron(III) Three‐Step Spin‐Crossover Complex 下载免费PDF全文
Dr. Zhao‐Yang Li Dr. Hiroyoshi Ohtsu Dr. Tatsuhiro Kojima Dr. Jing‐Wei Dai Takefumi Yoshida Dr. Brian K. Breedlove Dr. Wei‐Xiong Zhang Dr. Hiroaki Iguchi Prof. Osamu Sato Prof. Masaki Kawano Prof. Masahiro Yamashita 《Angewandte Chemie (International ed. in English)》2016,55(17):5184-5189
A neutral mononuclear FeIII complex [FeIII(H‐5‐Br‐thsa‐Me)(5‐Br‐thsa‐Me)]?H2O ( 1 ; H2‐5‐Br‐thsa‐Me=5‐bromosalicylaldehyde methylthiosemicarbazone) was prepared that exhibited a three‐step spin‐crossover (SCO) with symmetry breaking and a 14 K hysteresis loop owing to strong cooperativity. Two ordered intermediate states of 1 were observed, 4HS–2LS and 2HS–4LS, which exhibited reentrant phase‐transition behavior. This study provides a new platform for examining multistability in SCO complexes. 相似文献
64.
A population model including diffusion, chemotaxis and growth is studied. Assuming that the diffusion rate and the chemotactic rate are both very small compared with the growth rate, we derive a new equation to describe the time-evolution of the aggregating region of biological individuals and show the conditions for the existence and stability of radially symmetric equilibrium solutions of the equation, which indicate the aggregation of individuals. 相似文献
65.
Thermoosmosis through anion-exchange membranes was measured for 10-3 to 2 mol/kg of aqueous KCl, LiCl, and NH4Cl and for 10-3 to 3 x 10-1 mol/kg of aqueous KIO3 and K2SO4. For all electrolytes used the direction of thermoosmosis was from the cold side to the hot side over the whole range of concentrations. For KCl and LiCl the experimental results were analyzed with an extension of a previously published theory, using additional data for transport numbers of ions in membranes and for electroosmosis. The agreement between theory and experiment is satisfactory. The absolute value of thermoosmosis for KIO3 is larger than that for other electrolytes because the pore volume fraction of the membrane for KIO3 is larger than that for the other electrolytes. 相似文献
66.
Y. Ohtsu H. Fukui T. Kanda K. Nakamura M. Nakano O. Nakata Y. Fujiyama 《Chromatographia》1987,24(1):380-384
Summary Silicone polymer-coated silica gels modified with octadecyl and octyl groups (S/S-C18, S/S-C8), or “capsule-type silica gels” were developed as packing materials for reversed-phase liquid chromatography. They were obtained
by coating the surface of totally porous silica gel with a homogeneous silicone polymer film, and thereafter modifying the
coating polymer with octadecyl or octyl groups. Retaining the advantages of silica-based packings, they show strong resistance
of alkali-like organic porous polymeric materials. 相似文献
67.
Emission ratiometric imaging of intracellular zinc: design of a benzoxazole fluorescent sensor and its application in two-photon microscopy 总被引:7,自引:0,他引:7
Zinc and calcium are ubiquitous intracellular metals, and while a variety of quantitative probes have been developed for measuring intracellular changes in calcium concentration, the same is not true of zinc. We describe here the design, synthesis, and properties of the benzoxazole-based, ratiometric zinc probe, Zinbo-5. This bright fluorescent reporter has a quantum yield of 0.1 in the zinc-form, exhibits a Kd for Zn2+ in the nanomolar range, and shows significant changes in both excitation and emission maxima upon zinc binding. The utility of this cell permeable probe is demonstrated in fluorescence microscopy emission ratio imaging experiments on mammalian cells. We further show that Zinbo-5 is well suited for two-photon excitation microscopy ratio imaging and can readily reveal changes in intracellular zinc concentration within optical planes of single cells. To the best of our knowledge, this is the first example of two-photon excitation microscopy applied to ratio imaging of zinc. These methods can be applied to real-time emission or excitation ratio imaging studies of zinc physiology in living cells. 相似文献
68.
Naomichi Furukawa Toshiaki Yoshimura Masami Ohtsu Takeshi Akasaka Shigeru Oae 《Tetrahedron》1980,36(1):73-80
The Michael type additions of diphenyl N-unsubstituted sulfimide (free sulfimide) to various electrophilic olefins were carried out. The reaction with cis- and trans-dibenzoylethylene, dimethyl-fumarate, dimethylmaleate, benzalacetophenone and benzalacetone gave mainly the corresponding trans-2-acylaziridines and trans-enaminoketones. However, phenyl vinyl sulfone or acrylonitrile afforded not the corresponding aziridine but diphenyl-N-2-cyano or N-2-phenylsulfonylethylsulfimide, a simple Michael adduct When optically active (+)-(R)-o-methoxyphenyiphenyl free sulfimide was treated with such an α,β-unsaturated carbonyl compound as benzalacetopbenone, an optically active 2-acylazindine, i.e., (-)-trans-2-benzoyl-3-phenylaziridine was obtained in ca 30% optical purity and its absolute configuration was assigned as (2R,3S) upon chemical transformation to the configuration-ally known 2-phenyl-2-benzoylamino-1-ethanol or by comparing its CD spectrum with that of (1R,2R)-1-phenyl-2-benzoyl-cyclopropane. Meanwhile, (-)-(S)-o-methoxyphenylphenyl free sulfimide was found to react with benzalacetophenone to afford (+)-trans-2-benzoyl-3-phenylaziridine of 25% optical purity. Effects of solvent and temperature on both die distribution of the products ratio and the optical yield were examined. 相似文献
69.
Dr. Qian Wu Prof. Dr. Masayasu Taki Yoshiki Tanaka Dr. Manish Kesherwani Prof. Dr. Quan Manh Phung Dr. Sawako Enoki Prof. Dr. Yasushi Okada Prof. Dr. Florence Tama Prof. Dr. Shigehiro Yamaguchi 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2024,136(15):e202400711
The development of near-infrared (NIR) fluorophores that have both excellent chemical stability and photostability, as well as efficient cell permeability, is highly demanded. In this study, we present phospha-rhodamine (POR) dyes which display significantly improved performance for protein labeling. This is achieved by incorporating a 2-carboxy-3-benzothiophenyl group at the 9-position of the xanthene scaffold. The resulting cis and trans isomers were successfully isolated and structurally characterized using X-ray diffraction. The HaloTag ligand conjugates of the two isomers exhibited different staining abilities in live cells. While the cis isomer showed non-specific accumulation on the organelle membranes, the trans isomer selectively labeled the HaloTag-fused proteins, enabling the long-term imaging of cell division and the 5-color imaging of cell organelles. Molecular dynamics simulations of the HaloTag ligand conjugates within the lipid membrane suggested that the cis isomer is more prone to forming oligomers in the membrane. In contrast, the oligomerization of the trans isomer is effectively suppressed by its interaction with the lipid molecules. By taking advantage of the superior labeling performance of the trans isomer and its NIR-emissive properties, multi-color time-lapse super-resolution 3D imaging, namely super-resolution 5D-imaging, of the interconnected network between the endoplasmic reticulum and microtubules was achieved in living cells. 相似文献
70.