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101.
We have considered itinerant memory dynamics in a chaotic neural network composed of four chaotic neurons with synaptic connections determined by two orthogonal stored patterns as a simple example of a chaotic itinerant phenomenon in dynamical associative memory. We have analyzed a mechanism of generating the itinerant memory dynamics with respect to intersection of a pair of alpha branches of periodic points and collapse of a periodic in-phase attracting set. The intersection of invariant sets is numerically verified by a novel method proposed in this paper. 相似文献
102.
103.
Yoko Masuda Kozue Hirabayashi Keiko Sakuma Tadashi Nakanishi 《Colloid and polymer science》2002,280(5):490-494
The swelling behavior of poly(ethylene oxide) (PEO) gels in aqueous solutions of sodium dodecyl sulfate (SDS) with and without
NaCl was investigated. In the absence of NaCl, PEO gels with different degrees of cross-linking began to swell from a concentration
lower than the critical micelle concentration (cmc) of SDS, then showed sigmoidal enhancements of swelling in a higher SDS
concentration region until the degrees of swelling reached maximum values. The SDS concentration at which the swelling began
to appear was in reasonable agreement with the critical aggregation concentration (cac) value reported for the aqueous PEO
system. For the cases where NaCl was present, the swelling behavior of PEO gel was different from that when NaCl was absent
in the following way. The concentrations where the swelling begins to appear, and hence those where the degree of swelling
rises steeply, decreased with an increase in NaCl concentration. The ultimate degrees of swelling at higher concentration
regions also decreased with an increase in the NaCl concentration. The lowering of the SDS concentrations at which the PEO
gel began to swell is in line with the decreases in the cmc of SDS solutions containing NaCl and also with the decreases in
the cac of PEO solution.
Electronic Publication 相似文献
104.
Tetsuya Yuasa Shinji Tanosaki Yoshiaki Sasaki Michiaki Takagi Akira Ishikawa Hiroshi Taniguchi Balasigamani Devaraj Takao Akatsuka 《Analytical sciences》2002,18(12):1329-1333
The coherent detection imaging (CDI) method uses the optical heterodyne detection technique. CW and single frequency lasers having long coherence lengths are used to exploit the maximum advantages of heterodyne detection, such as high directionality, selectivity and sensitivity. The CDI method based on optical heterodyne detection enables selective filtering of the directional coherence-retaining emergent photons, which leads to image reconstruction from projections, similar to X-ray computed tomography (CT). So far we have demonstrated the advantages and capabilities of the measurement technique for transillumination optical computed tomography in biomedicine. Here, we investigate the fundamental imaging properties of CDI method, such as its high directionality and quantitativeness, with preliminary physical phantom experiments. The results show that the CDI method satisfies the requirements for CT reconstruction under the first order approximation, and enables quantitative measurements in the sense that the relationship between estimated and actual concentration retains a satisfactory linearity. 相似文献
105.
Kazuchika Ohta Hiroshi Ema Yasue Morizumi Takuya Watanabe Tetsuya Fujimoto Iwao Yamamoto 《Liquid crystals》1990,8(3):311-330
Two novel types of transition-metal-containing liquid crystals, bis(p-n-koxydithiobenzoato)nickel(II) (abbreviated as (CnO-DTB)2Ni), and (p-n-alkoxydithiobenzoato)(p-n-alkoxyperthiobenzoato)nickel(II) (abbreviated as (CnO-DTB)(CnO-PTB)Ni), were synthesized. It was found that the (CnO-DTB)2Ni complex for n = 8 has smectic H and C mesophases, and that the (CnO-DTB)2Ni complexes for n = 4 and 8 easily transform into the corresponding monoperthio complexes, nO-PTB)Ni, by heating at temperatures between 230°C and 285°C. It was confirmed that the transformation originates from an intermolecular reaction between the (CnO-DTB)2Ni complexes at high temperatures, and that the origin of the extra sulphurs in the resulting (CnO-DTB)(CnO-PTB)Ni complexes is the neighbouring (CnO-DTB)2Ni complexes. Interestingly, each of the (CnO-DTB)(CnO-PTB)Ni complexes (n = 4 and 8), has nematic mesophase and exhibits a unique double melting behaviour via the nematic phase, which is the first example in liquid crystals. The reversible transformation between the blue smectic rod-like (CnO-DTB)2Ni complex and the red nematic Λ-like (CnO-DTB)(CnO-PTB)Ni complex is possible. 相似文献
106.
The ionic conduction of cation substituted CuBrTe, CuxAg1−xBrTe solid solutions, is investigated in the temperature range between 100 and 400 K. The change of electrical conductivities with temperature in the range of 0.94≤x<1 shows the characteristics of second-order rather than first-order phase transitions. The replacement of Cu with the Ag cation in CuxAg1−xBrTe leads to an increase in conductivity especially in the β and γ-phases. 相似文献
107.
Tetsuya Ishiu 《Topology and its Applications》2008,155(11):1256-1263
We proved that ?+ implies the existence of a non-D-space whose all closed subspace F satisfies e(F)=L(F). The existence of such a space under MA+¬CH or PFA is also discussed. 相似文献
108.
109.
Naoki Furutani Tetsuya Takahashi Nobushige Naito Takafumi Maruishi Yuko Yoshimura Chiaki Hasegawa Tetsu Hirosawa Mitsuru Kikuchi 《Entropy (Basel, Switzerland)》2021,23(4)
Recently, measuring the complexity of body movements during sleep has been proven as an objective biomarker of various psychiatric disorders. Although sleep problems are common in children with autism spectrum disorder (ASD) and might exacerbate ASD symptoms, their objectivity as a biomarker remains to be established. Therefore, details of body movement complexity during sleep as estimated by actigraphy were investigated in typically developing (TD) children and in children with ASD. Several complexity analyses were applied to raw and thresholded data of actigraphy from 17 TD children and 17 children with ASD. Determinism, irregularity and unpredictability, and long-range temporal correlation were examined respectively using the false nearest neighbor (FNN) algorithm, information-theoretic analyses, and detrended fluctuation analysis (DFA). Although the FNN algorithm did not reveal determinism in body movements, surrogate analyses identified the influence of nonlinear processes on the irregularity and long-range temporal correlation of body movements. Additionally, the irregularity and unpredictability of body movements measured by expanded sample entropy were significantly lower in ASD than in TD children up to two hours after sleep onset and at approximately six hours after sleep onset. This difference was found especially for the high-irregularity period. Through this study, we characterized details of the complexity of body movements during sleep and demonstrated the group difference of body movement complexity across TD children and children with ASD. Complexity analyses of body movements during sleep have provided valuable insights into sleep profiles. Body movement complexity might be useful as a biomarker for ASD. 相似文献
110.
Junro Yoshino Dr. Akiko Furuta Tetsuya Kambe Hiroaki Itoi Naokazu Kano Prof. Takayuki Kawashima Prof. Yuzuru Ito Dr. Makoto Asashima Prof. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(17):5026-5035
2‐[Bis(pentafluorophenyl)boryl]azobenzenes bearing hydrogen, methoxy, dimethylamino, trifluoromethyl, fluoro, n‐butyl, and tert‐butyldimethylsiloxy groups at the 4′‐position or methoxy and bromo groups at the 4‐position have been synthesized. The 4‐bromo group of the 2‐boryl‐4‐bromoazobenzene derivative was converted to phenyl and diphenylamino groups by palladium‐catalyzed reactions. The absorption and fluorescence properties have been investigated using UV/Vis and fluorescence spectroscopy. The 2‐borylazobenzenes emitted an intense green, yellow, and orange fluorescence, in marked contrast to the usual azobenzene fluorescence. The 4′‐siloxy derivative showed the highest fluorescence quantum yield (0.90) among those reported for azobenzenes to date. The correlation between the substituent and the fluorescence properties was elucidated by studying the effect of the substituent on the relaxation process and from DFT and TD‐DFT calculations. An electron‐donating group at the 4′‐position was found to be important for an intense emission. Application of fluorescent azobenzenes as a fluorescent vital stain for the visualization of living tissues was also investigated by microinjection into Xenopus embryos, suggesting these compounds are nontoxic towards embryos. 相似文献