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61.
Yoshiki K Kanamaru R Ryosuke K Hashimoto M Hashimoto N Araki T 《Optics letters》2007,32(12):1680-1682
We developed a compact polarization-mode converter for microscopy to control three-dimensional polarization at the focus. The converter consisted of two homogeneously aligned liquid-crystal spatial light modulators with eight independently controllable electrodes (segments), and a quarter-waveplate. The converter converted a linearly polarized beam to three polarization modes: two orthogonal linear polarizations and a pseudo-radial polarization. We applied the converter to second-harmonic-generation microscopy and demonstrated the detection of three-dimensional molecular orientation. 相似文献
62.
Overview of software options for processing,analysis and interpretation of mass spectrometric proteomic data
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Recently, the interests in proteomics have been intensively increased, and the proteomic methods have been widely applied to many problems in cell biology. If the age of 1990s is considered to be a decade of genomics, we can claim that the following years of the new century is a decade of proteomics. The rapid evolution of proteomics has continued through these years, with a series of innovations in separation techniques and the core technologies of two‐dimensional gel electrophoresis and MS. Both technologies are fueled by automation and high throughput computation for profiling of proteins from biological systems. As Patterson ever mentioned, ‘data analysis is the Achilles heel of proteomics and our ability to generate data now outstrips our ability to analyze it’. The development of automatic and high throughput technologies for rapid identification of proteins is essential for large‐scale proteome projects and automatic protein identification and characterization is essential for high throughput proteomics. This review provides a snap shot of the tools and applications that are available for mass spectrometric high throughput biocomputation. The review starts with a brief introduction of proteomics and MS. Computational tools that can be employed at various stages of analysis are presented, including that for data processing, identification, quantification, and the understanding of the biological functions of individual proteins and their dynamic interactions. The challenges of computation software development and its future trends in MS‐based proteomics have also been speculated. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
63.
Kei Fujise Eiji Tsurumaki Gaku Fukuhara Nobuyuki Hara Yoshitane Imai Shinji Toyota 《化学:亚洲杂志》2020,15(16):2456-2461
Polycyclic aromatic hydrocarbons consisting of three fused anthracene units were designed as new π‐conjugated compounds having helical structures. These expanded helicenes were synthesized by Pt‐catalyzed cycloisomerization of the corresponding ethynyl‐substituted precursors. The nonplanar and helical structure was confirmed by X‐ray analysis and DFT calculations, and the barrier to helical inversion was estimated to be 34 kJ mol?1. The enantiomers of the diphenyl derivative were successfully resolved by chiral HPLC. Enantiopure samples showed good chiroptical performance in the CD (|Δ?| 1380 L mol?1 cm?1) and CPL (|glum| 0.013) spectra, and these values were considerably large for simple organic molecules. The unique chiroptical properties are discussed on the basis of the molecular structure and the electronic state with the aid of time‐dependent DFT calculations. 相似文献
64.
Nobuyuki Tanaka 《Macromolecular Symposia》1996,102(1):429-431
The possibility of porosity control in N6/N66 membranes prepared from N6/N66 blend solutions of calcium chloride – methanol mixture was investigated. For N6/N66 blend solutions at 10 °C and 20 °C, the four-phase structure of solid, gel 1, gel 2 and solution was observed clearly in the pore formation process after adding water on a solution surface. In the boundary part between gel 1 and gel 2, the phase separation of N6 and N66 was predicted. The macroscopic pores of blend membranes prepared at 10°C and 20 °C were almost spherical. 相似文献
65.
Jun Koyanagi Keita Takeguchi Kazuki Murai Hirokazu Furue Nobuyuki Masuda 《Molecular Crystals and Liquid Crystals》2017,656(1):54-65
Blue-phase liquid crystals form three-dimensional structures in a self-organizing manner and are similar to living tissue structures such as the teeth of mice and collagen tissues. This study presents numerical results regarding the conditions under which blue-phase liquid crystals occur. The Monte Carlo simulations are performed by employing an improved Lennard–Jones potential that considers anisotropy and chirality. The conditions for the formation of the blue phase, which vary with respect to the chirality, are examined first. The relationship between the anisotropic parameters and the chiral parameter for the formation of the blue phase is discussed. Identical blue-phase structures are obtained, even when the cell size and molecular number are varied drastically. This discussion is useful for considering the scale-up problem, which is almost always a difficult issue for molecular-scale simulations. 相似文献
66.
67.
Kota Tanaka Saki Okamura Ken Shibata Naoki Ikenaga Nobuyuki Tanaka Kazumi Hakamada Jun Miyake 《Research on Chemical Intermediates》2016,42(11):7723-7730
Renewable energy is regarded as a clean energy source but has some problems, one of which is intermittency. To reduce this, the time-delay of hydrogen production by photosynthetic bacteria can be effective. In this study, we qualitatively evaluated the time-delay of hydrogen production by photosynthetic bacteria under various irradiation conditions, and we also quantitatively evaluated it by fitting the experimental data and the hydrogen production model with a genetic algorithm. As a result of model fitting, we found that the relationship between the lengths of the optimized time-delay of hydrogen production by photosynthetic bacteria and the amount of light irradiation is linear. And we also found that the time-delay of hydrogen production by photosynthetic bacteria had an upper limit under low light intensity. We have suggested the existence of an energy store mechanism in photosynthetic bacteria. 相似文献
68.
Tetsuya Ezawa Seunghee Jung Yuya Kawashima Takuya Noguchi Nobuyuki Imai 《Tetrahedron: Asymmetry》2017,28(1):75-83
Dipeptides and amides were obtained in high yields from N-carbobenzyloxy α-amino acids and 3-phenylpropanoic acid with unprotected α-amino acids via the corresponding mixed carbonic carboxylic anhydrides using ethyl chloroformate and triethylamine by an ecological and convenient method in which the protection of C-terminals is not needed. 相似文献
69.
The first syntheses of mono- and dianions of stannole were accomplished by transmetallation or reduction of the novel bi(1,1-stannole). 相似文献
70.
Koike Y Metoki N Haga Y McEwen KA Kohgi M Yamamoto R Aso N Tateiwa N Komatsubara T Kimura N Aoki H 《Physical review letters》2002,89(7):077202
The magnetic structure of the localized-5f uranium intermetallic compound U3Pd20Si6 has been determined by means of a neutron diffraction experiment. Our data demonstrate that this compound has a collinear coupling of the sublattice ordering of the uranium spins on the 4a and 8c sites. We conclude that higher-order exchange and/or quadrupole interactions are necessary to stabilize this unique collinear structure. We discovered a new type of spin-flop transition against the uniaxial anisotropy induced by this collinear coupling. 相似文献