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121.
It is important to understand the mechanism to integrate visual and other information for the perception of gravitational
vertical under different conditions of gravity, although most of the experiments to investigate the topic reported so far
has been carried out under normal-gravity (1 G) and under micro-gravity produced in short duration of parabolic flight. The
purpose of this research is to investigate human perception of gravitational vertical under hyper-gravity (1.5G and 2G) to
compare that under normal-gravity (1 G). We measured perceived gravitational vertical using a visual probe presented at the
center while manipulating the orientation of visual stimuli (scenery picture) presented in the surround and the magnitude
of gravitational acceleration. The environment of hyper-gravity was produced by centrifugal force of a rotating flight simulator.
The results show that the accuracy of perceived gravitational vertical increased and the precision of it decreased under hyper-gravity
condition relative to those under the normal-gravity condition when no visual stimulus was presented. However, the effect
of the tilt of visual stimuli did not change under different gravity conditions. 相似文献
122.
Tomoya Iwazaki Ryoujin Obinata Wataru Sugimoto Yoshio Takasu 《Electrochemistry communications》2009,11(2):376-378
Activated carbon prepared from silk fibroin, which is free of metal elements, showed a high catalytic activity for the oxygen-reduction reaction (ORR). The activated carbon had a very high onset potential of Eonset = 0.83 V (vs. RHE) in oxygen-saturated 0.5 M H2SO4 at 60 °C. The ORR on the activated carbon proceeded by a four-electron process in the high-electrode-potential region; this gradually decreased to a 3.5-electron reaction below about 0.6 V (vs. RHE). Only about 1% of nitrogen atoms (mostly quaternary) remained in the activated carbon by heat-treatment at up to 1200 °C are responsible for the high catalytic activity. The open circuit voltage of a polymer electrolyte fuel cell using the activated carbon as the cathode and a platinum/carbon black anode under pure oxygen and hydrogen gases, respectively, both at one atmosphere, was 0.96 V at 27 °C. 相似文献
123.
Subash C. B. Gopinath Koichi Awazu Makoto Fujimaki Katsuaki Sugimoto Yoshimichi Ohki Tetsuro Komatsubara Junji Tominaga Penmetcha K. R. Kumar 《Analytical and bioanalytical chemistry》2009,394(2):481-488
Biological self-assembly is a natural process that involves various biomolecules, and finding the missing partner in these
interactions is crucial for a specific biological function. Previously, we showed that evanescent-field-coupled waveguide-mode
sensor in conjunction with a SiO2 waveguide, the surfaces which contain cylindrical nanometric holes produced by atomic bombardment, allowed us to detect efficiently
the biomolecular interactions. In the present studies, we showed that the assembly of biomolecules can be monitored using
the evanescent-field-coupled waveguide-mode biosensor and thus provide a methodology in monitoring assembly process in macromolecular
machines while they are assembling.
Evanescent-field-coupled waveguide-mode sensor
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
124.
Sahnoun R Nakai K Sato Y Kono H Fujimura Y Tanaka M 《The Journal of chemical physics》2006,125(18):184306
We theoretically investigated the stability of highly charged C(60) (z+) cations produced from C(60) with an ultrashort intense laser pulse of lambda approximately 1800 nm. We first calculated the equilibrium structures and vibrational frequencies of C(60) (z+) as well as C(60). We then calculated key energies relevant to dissociation of C(60) (z+), such as the excess vibrational energy acquired upon sudden tunnel ionization from C(60). By comparing the magnitudes of the calculated energies, we found that C(60) (z+) cations up to z approximately 12 can be produced as a stable or quasistable (microsecond-order lifetime) intact parent cation, in agreement with the recent experimental report by V. R. Bhardwaj et al. [Phys. Rev. Lett. 93, 043001 (2004)] that almost only intact parent C(60) (z+) cations up to z=12 are detected by a mass spectrometer. The results of Rice-Ramsperger-Kassel-Marcus calculation suggest that the lifetime of C(60) (z+) drastically decreases by ten orders of magnitude as z increases from z=11 to z=13. Using the time-dependent adiabatic state approach, we also investigated the vibrational excitation of C(60) and C(60) (z+) by an intense near-infrared pulse. The results indicate that large-amplitude vibration with energy of >10 eV is induced in the delocalized h(g)(1)-like mode of C(60) (z+). 相似文献
125.
The first series of triangular cluster complexes of [MCo(2)] (M = Rh, Ir, Ru) with a planar metalladithiolene ring coordinating in the eta(3)-bonding mode were synthesized, and the crystal structures, spectral and electrochemical properties, and thermochromism of these complexes were revealed. 相似文献
126.
127.
Efficient monocyclic 1,2-diazepine formation via a tandem electrocyclization reaction of cyclobutenones with lithiodiazoacetate is demonstrated. The reaction proceeds through an oxy anion-accelerated 4π-ring opening of cyclobutene followed by an 8π-ring closure of the resultant oxy anion-substituted diazo-diene under mild conditions to furnish a 1,2-diazepine via formal diazomethylene insertion into the C-C bond of cyclobutenone. 相似文献
128.
Chiral‐Substrate‐Assisted Stereoselective Epoxidation Catalyzed by H2O2‐Dependent Cytochrome P450SPα
Dr. Takashi Fujishiro Dr. Osami Shoji Dr. Norifumi Kawakami Takahiro Watanabe Dr. Hiroshi Sugimoto Dr. Yoshitsugu Shiro Prof. Dr. Yoshihito Watanabe 《化学:亚洲杂志》2012,7(10):2286-2293
The stereoselective epoxidation of styrene was catalyzed by H2O2‐dependent cytochrome P450SPα in the presence of carboxylic acids as decoy molecules. The stereoselectivity of styrene oxide could be altered by the nature of the decoy molecules. In particular, the chirality at the α‐positions of the decoy molecules induced a clear difference in the chirality of the product: (R)‐ibuprofen enhanced the formation of (S)‐styrene oxide, whereas (S)‐ibuprofen preferentially afforded (R)‐styrene oxide. The crystal structure of an (R)‐ibuprofen‐bound cytochrome P450SPα (resolution 1.9 Å) revealed that the carboxylate group of (R)‐ibuprofen served as an acid–base catalyst to initiate the epoxidation. A docking simulation of the binding of styrene in the active site of the (R)‐ibuprofen‐bound form suggested that the orientation of the vinyl group of styrene in the active site agreed with the formation of (S)‐styrene oxide. 相似文献
129.
B Busch N Ueberschaar Y Sugimoto C Hertweck 《Journal of the American Chemical Society》2012,134(30):12382-12385
The course of the enigmatic iterative use of a polyketide synthase module was deduced from targeted domain inactivation in the aureothin assembly line. Mutational analyses revealed that the N-terminus of AurA is not involved in the iteration process, ruling out an ACP-ACP shuttle. Furthermore, an AurA(KS°, ACP°)-AurA(AT(0)) heterodimer proved to be nonfunctional, whereas aureothin production was restored in a ΔaurA mutant complemented with AurA(KS°)-AurA(ACP°). This finding supports a model according to which the ACP-bound polyketide intermediate is transferred back to the KS domain on the opposite PKS strand. 相似文献
130.
We carried out an experimental and numerical investigation of photoinduced voltage at normal incidence in the nondiffraction regime, which was not predicted to occur by the simple momentum conservation model. We prepared two samples: one having space inversion symmetry and the other without this feature. At normal incidence in the nondiffraction regime, we observed a finite signal only for the asymmetric structure. We found that surface plasmon polaritons (SPPs) are excited by the signal and are attributed to the origin of the voltage. We also evaluated the radiation force of light by using the Maxwell stress tensor and found that pressure of light and not shear force is mainly induced in the structure due to the asymmetric excitation of SPPs. 相似文献