担当区分：責任著者   掲載種別：研究論文（学術雑誌）   国際・国内誌：国際誌  

DOI： 10.1021/acsomega.1c07206

PubMed

掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）  

DOI： 10.1541/ieejeiss.141.668

CiNii Article

J-GLOBAL

掲載種別：研究論文（学術雑誌）  

DOI： 10.1117/12.2616159

掲載種別：研究論文（学術雑誌）  

DOI： 10.1117/12.2616108

掲載種別：研究論文（学術雑誌）  

DOI： 10.3390/MI11090830

PubMed

掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpcc.0c00826

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： https://doi.org/10.1117/12.2573759

掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.jpcc.9b11663

掲載種別：研究論文（学術雑誌）  

© 2020 Author(s). High-density cultured neuronal networks have been used to evaluate synchronized features of neuronal populations. Voltage-sensitive dye (VSD) imaging of a dissociated cultured neuronal network is a critical method for studying synchronized neuronal activity in single cells. However, the signals of VSD are generally too faint - that is, the signal-to-noise ratio (S/N) is too low - to detect neuronal activity. In our previous research, a silver (Ag) plasmonic chip enhanced the fluorescence intensity of VSD to detect spontaneous neural spikes on VSD imaging. However, no high-density network was cultivated on the Ag plasmonic chip, perhaps because of the chemical instability of the Ag surface. In this study, to overcome the instability of the chip, we used a chemically stable gold (Au) plasmonic dish, which was a plastic dish with a plasmonic chip pasted to the bottom, to observe neuronal activity in a high-density neuronal network. We expected that the S/N in real-time VSD imaging of the Au plasmonic chip would be improved compared to that of a conventional glass-bottomed dish, and we also expected to detect frequent neural spikes. The increase in the number of spikes when inhibitory neurotransmitter receptors were inhibited suggests that the spikes corresponded to neural activity. Therefore, real-time VSD imaging of an Au plasmonic dish was effective for measuring spontaneous network activity in a high-density neuronal network at the spatial resolution of a single cell.

DOI： 10.1063/1.5131497

PubMed

掲載種別：研究論文（国際会議プロシーディングス）  

DOI： 10.1117/12.2573759

掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/j.jphotochem.2019.111949

掲載種別：研究論文（学術雑誌）   共著区分：共著   国際・国内誌：国際誌  

DOI： 10.3934/Neuroscience.2019.4.240

掲載種別：研究論文（学術雑誌）  

© 2012 IEEE. Neurons behave like transistors, but have fluctuating characteristics. In this paper, we show that several asynchronous multiplex communication channels can be established in a 2-D mesh neural network with randomly generated weights between eight neighbors. Neurons were simulated by integrate-and-fire neuron models without leakage and with fluctuating refractory period and output delay. If one of the transmitting neuron groups is stimulated, the signal is propagated in the form of spike waves. The corresponding receiving neuron group is able to identify the signal after having learned to form an asynchronous multiplex communication channel. The channel is composed of many intermediate/interstitial neurons working as relays. Each neuron can work as an I/O and as a relay element, i.e., as a multiuse unit. Grouping and synchronic firing is often seen in natural neuronal networks and seems to be effective for stable/robust communication in conjunction with spatial multiplex communication. This communication pattern corresponds to our wet lab experiments on cultured neuronal networks and is similar to sound identification by the ear and mobile adaptive communication systems.

DOI： 10.1109/TNNLS.2018.2880565

PubMed

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.7567/1347-4065/ab0887

その他URL： https://doi.org/10.7567/1347-4065/ab0887

掲載種別：研究論文（国際会議プロシーディングス）  

© Published under licence by IOP Publishing Ltd. It is well-recognized that the Brownian motion of particles in fluids is random. Nevertheless, there can be characteristics depending on the specific physical conditions. We analyze the system of nanoparticle clusters formed by the laser trapping force field at the solid-liquid interface, based on the microscopy movie data. Since the laser trapping force field is basically a function of radial distance from the focal point in the two dimension at the liquid-solid interface, we examine the difference of displacement distributions in the radial and circumferential directions. The results show that the basic characteristics in this system depends on the laser power, and there is an anisotropy in the stochastic motion of the nanoparticles.

DOI： 10.1088/1742-6596/1220/1/012015

掲載種別：研究論文（国際会議プロシーディングス）  

© Published under licence by IOP Publishing Ltd. Nanoparticles in a cluster trapped by laser-induced force field show Brownian motion at solid-liquid interfaces. The cluster formation means that the particles are highly concentrated. In general, the diffusion coefficients of particles in fluids decrease with substantially high concentration and also in the vicinity of solid walls due to the hydrodynamic effect. The particle trajectory data obtained from the experimental measurements show that the longer time span of observation leads to smaller diffusion coefficient due to the confinement effect. However, they also exhibit higher diffusion coefficient compared to the the bulk condition when evaluated at a sufficiently short time span of the frame interval under the condition of sufficiently high laser powers.

DOI： 10.1088/1742-6596/1220/1/012054

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（学術雑誌）  

DOI： 10.3934/Neuroscience.2019.4.240

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1039/c8nj02465k

掲載種別：研究論文（学術雑誌）  

© 2018 American Chemical Society. Optical trapping and manipulation techniques have attracted significant attention in various research fields. Optical forces divided into two terms, such as a scattering force and gradient one, work to push forward and attract objects, respectively. This is a typical property of optical forces. In particular, a tool known as optical tweezers can be created when a laser beam is converged at a focal point, causing strong forces to be generated so as to trap and manipulate small objects. In this study, we propose a novel method to build up assembled structures of polystyrene particles by using optical trapping techniques. Recording trajectories of single particles, the optical forces are quantitatively evaluated using particle tracking velocimetry. Herein, we treat various particle sizes whose diameters range from 1 to 4 μm and expose them to a converged laser beam of 1064 nm wavelength. As a result, both experimental and theoretical results are in good agreement. The behavior of particles is understood in the framework of Ashkin's ray optics. This finding clarifies optical force fields of microparticles distributed in a slit-like microfluidic channel and will be applicable for effectively forming ordered structures in liquids.

DOI： 10.1021/acs.jpcc.8b02701

掲載種別：研究論文（学術雑誌）   共著区分：共著  

© 2018 the Author(s). Neuronal networks have fluctuating characteristics, unlike the stable characteristics seen in computers. The underlying mechanisms that drive reliable communication among neuronal networks and their ability to perform intelligible tasks remain unknown. Recently, in an attempt to resolve this issue, we showed that stimulated neurons communicate via spikes that propagate temporally, in the form of spike trains. We named this phenomenon "spike wave propagation". In these previous studies, using neural networks cultured from rat hippocampal neurons, we found that multiple neurons, e.g., 3 neurons, correlate to identify various spike wave propagations in a cultured neuronal network. Specifically, the number of classifiable neurons in the neuronal network increased through correlation of spike trains between current and adjacent neurons. Although we previously obtained similar findings through stimulation, here we report these observations on a physiological level. Considering that individual spike wave propagation corresponds to individual communication, a correlation between some adjacent neurons to improve the quality of communication classification in a neuronal network, similar to a diversity antenna, which is used to improve the quality of communication in artificial data communication systems, is suggested.

DOI： 10.3934/Neuroscience.2018.1.18

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1117/12.2319362

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（学術雑誌）  

© 2018 OSA - The Optical Society. All rights reserved. Fluorescent imaging is a powerful technique to reveal how target cells or biomolecules work in biological tissues and cells. So far, organic dyes, fluorescent proteins, and quantum dots have been developed and widely used as a fluorescent probe. However, these fluorescent probes do not work well in certain conditions: they have cytotoxicity and steric hindrance due to inclusion of harmful atoms and/or their sizes. Hence, metal nanoclusters, that are composed of several metal atoms and emit fluorescence owing to quantum size effect, have been anticipated as a newly categorized fluorescent probe. Since the fluorescent wavelength depends on their sizes, it is possible to control the fluorescent wavelength by adjusting the number of composed atoms [1].

掲載種別：研究論文（国際会議プロシーディングス）  

Copyright© (2018) by Chemical and Biological Microsystems Society.All rights reserved. Optical forces are well known as providing a noncontact method of manipulating micro- or nano-sized particles. In previous studies, however, it has been reported that the trapping power of the optical tweezers is smaller than that of the movement of the particles (eg. Brownian motion) and it becomes unstable trapping. Since the trapping force decreases in proportion to the size of the target, it is extremely difficult to precisely manipulate nano-sized particles. On the other hand, the use of ultrasmall confined spaces of well-defined nanofluidic environments will provide new mechanisms and technologies for manipulating nano-sized particles in liquid phase. These features contribute to the suppression of the Brownian motion of nanoparticles in 3D nano space. The integration of optical forces and nanofluidics would allow single nanoparticles to be captured, transported and arrayed in nanofluidic systems.

掲載種別：研究論文（学術雑誌）  

© The Royal Society of Chemistry and the Centre National de la Recherche Scientifique. InP-based quantum dots (QDs) have been proposed as an alternative to CdSe-based QDs for both bioimaging and device displays. In this work, we incorporate hydrophilic InP/ZnS QDs into silica nanocapsules. The morphology, number of incorporated QDs, and photoluminescence (PL) properties of the capsules depend on the alkoxide hydrolysis conditions. By selecting a method of QD surface silanization, multiple QDs (typically 3) are incorporated into the nanocapsules (∼40 nm in size) without causing significant deterioration of the initial PL efficiency (up to 36%). Degradation analysis in different buffer solutions indicates that silica nanocapsules have higher stabilities than pristine QDs. The surface of the nanocapsules was modified with carboxyl groups without any change in morphology. Bright PL images with high resolution were obtained after introducing the nanocapsules into rat hippocampal neurons, when compared with commercial Q-trackers (polymer coated CdSe/ZnS QDs).

DOI： 10.1039/c8nj02465k

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1364/OE.25.010622

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1117/12.2275026

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（国際会議プロシーディングス）  

© 2016 IEEE. It is a mystery that neural network composed of neurons with fluctuating characteristics can transmit information well reliably. In this paper, we show, in a simulation using a 9×9 2D mesh neural network, 9 to 1 multiplex communication is possible with 99% correct rate. Neurons are modeled by integrate and fire model without leak. Spikes spreads from transmitting neuron groups, propagated as spike waves, and received by receiving neurons. Then, the receiving neurons classify from which neuron group the spike waves come by back propagation neural network (BPN) method.

DOI： 10.1109/CISP-BMEI.2016.7852824

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.3934/Neuroscience.2017.1.1.

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.3934/Neuroscience.2016.4.385.

掲載種別：研究論文（学術雑誌）   共著区分：共著  

© 2016 The Japan Society of Applied Physics.Living neurons in a complex neuronal network communicate with each other through synaptic connections. The molecular dynamics of cell surface molecules localized at synaptic terminals is essential for functional connections via synaptic plasticity in the neuronal network. Here, we demonstrate surface-plasmon-resonance-based optical trapping using a plasmonic chip toward realizing effective manipulation of molecules on the surface of neurons. Surface-plasmon-enhanced optical trapping was evaluated by the fluorescence analysis of nanoparticles suspended in water and neural cell adhesion molecules (NCAMs) labeled with quantum dots (Q-dots) on rat hippocampal neurons. The motion of nanoparticles in water and the molecular dynamics of NCAMs on neuronal cells cultured on a plasmonic chip were constrained at the laser focus more effectively than those on a glass substrate because of the surface plasmon resonance effect.

DOI： 10.7567/JJAP.55.06GN04

掲載種別：研究論文（学術雑誌）   共著区分：共著  

© 2016 The Japan Society of Applied Physics. A plastic dish with a wavelength-scale periodic structure at a bottom panel was integrally molded and coated with thin metal films. The integrally molded dish called plasmonic dish was applied to bioimaging under a fluorescence microscope. On the plasmonic substrate, the enhanced electric field based on a grating-coupled surface plasmon resonance (GC-SPR) can provide an enhanced fluorescence. In this study, two kinds of cells, human embryonic kidney (HEK) cells and neuronal cells, were observed in our plasmonic dish. Fluorescence images of HEK cells were above 10 times brighter than those obtained on a conventional glass-bottomed dish. Neuronal cells were successfully cultured for 10 d on the plasmonic dish integrally molded, and in fluorescence images with transmitted light, a higher contrast was obtained than in epifluorescence images. The plasmonic dish integrally molded, as well as that fabricated by the UV nanoimprint method, was also found to be useful for sensitive bioimaging.

DOI： 10.7567/JJAP.55.03DF12

掲載種別：研究論文（国際会議プロシーディングス）  

© 2015 IEEE. It's important for understanding brain intelligence to investigate how the signal/information is flown in neuronal network. We observed spike trains obtained by one-shot electrical stimulation with 8 × 8 multi-electrodes in cultured neuronal networks. Each electrode is considered to collect spikes from several neurons. We then constructed code flow maps as movies of the electrode array to observe the code flow especially of 1101 and 1011. To quantify the flow, we calculated the cross-correlations of the maximum direction of the codes with lengths less than 8. Normalized cross-correlations in the maximum direction were almost constant irrespective of code. Thus, the analysis suggested that the local codes for electrode flow maintained the code shape to some extent and conveyed information in the neural network. Then we made simulation of such code flow, and could estimate rough characteristics of neurons including refractory period and distribution of connection weights between neurons.

DOI： 10.1109/FSKD.2015.7382211

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1155/2016/7186092

その他URL： http://dblp.uni-trier.de/db/journals/cin/cin2016.html#journals/cin/TamuraNHMS16

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1155/2016/7267691

その他URL： http://dblp.uni-trier.de/db/journals/cin/cin2016.html#journals/cin/TamuraNHMSKYMC16

掲載種別：研究論文（学術雑誌）  

© 2016 Shinichi Tamura et al. It remains a mystery how neural networks composed of neurons with fluctuating characteristics can reliably transmit information. In this study, we simulated a 9 × 9 2D mesh neural network consisting of an integrate-and-fire model without leak, and connection weights that were randomly generated. The characteristics of the refractory period and output delay of the neurons were fluctuated time to time. Spikes from transmitting neuron groups spread (propagated as spike waves) to receiving neurons. For 9 to 1 multiplex communication with a back propagation neural network (BPN), the receiving neurons successfully classified which neuron group transmitted the spike at a rate of 99%. In other words, the activity of the neuron group is propagated in the neural network as spike waves in a broadcasting manner and the wave fragment is received by receiving neurons. Next, point-to-point signal transmission in the neural network is carried out by multi-path, multiplex communication, and diversity reception. Each neuron can function in 3 ways of transmit, relay (transfer), and receive; however, most neurons act as a local relaying media. This type of mechanism is similar to sound propagation through air. Our research group studies the functions of neural networks by combining experiments with cultured neuronal networks with artificial neural network simulations. This current study corresponding to our previous work on the ability of remote receiving neurons to identify two transmitting neuron groups stimulated in a cultured neuronal network, i.e., 2 to 1 communication. These mechanisms may be the basis of higher cortical functions.

DOI： 10.3934/Neuroscience.2016.4.385

掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（国際会議プロシーディングス）  

© 2015 IEEE. It's important to investigate natural intelligence how the signal/ information is flown in neuronal network. We observed spike trains produced by one-shot electrical stimulation with 8 × 8 multi-electrodes in cultured neuronal networks. Each electrode accepted spikes from several neurons. We then constructed code flow maps as movies of the electrode array to observe the code flow especially of '1101' and '1011.' To quantify the flow, we calculated the cross-correlations of the maximum direction of the codes with lengths less than 8. Normalized cross-correlations in the maximum direction were almost constant irrespective of code. Thus, the analysis suggested that the local codes for electrode flow maintained the code shape to some extent and conveyed information in the neural network. Then we made simulation of such code flow.

DOI： 10.1109/ICCIS.2015.7274571

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1109/FSKD.2015.7382211

その他URL： http://dblp.uni-trier.de/db/conf/fskd/fskd2015.html#conf/fskd/TamuraNHMC15

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1117/12.2076348

掲載種別：研究論文（学術雑誌）  

© 2014 American Chemical Society. A plasmonic dish was fabricated as a novel cellculture dish for in situ sensitive imaging applications, in which the cover glass of a glass-bottomed dish was replaced by a grating substrate coated with a film of silver. Neuronal cells were successfully cultured over a period of more than 2 weeks in the plasmonic dish. The fluorescence images of their cells including dendrites were simply observed in situ using a conventional fluorescence microscope. The fluorescence from neuronal cells growing along the dish surface was enhanced using the surface plasmon resonance field. Under an epi-fluorescence microscope and employing a donut-type pinhole, the fluorescence intensity of the neuron dendrites was found to be enhanced efficiently by an order of magnitude compared with that using a conventional glass-bottomed dish. In a transmitted-light fluorescence microscope, the surface-selective fluorescence image of a fine dendrite growing along the dish surface was observed; therefore, the spatial resolution was improved compared with the epi-fluorescence image of the identical dendrite. (Chemical Equation Presented).

DOI： 10.1021/am505579u

PubMed

掲載種別：研究論文（学術雑誌）  

その他URL： http://orcid.org/0000-0002-5736-1187

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1541/ieejeiss.134.1071

J-GLOBAL

掲載種別：研究論文（その他学術会議資料等）   共著区分：共著  

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（学術雑誌）   共著区分：共著  

掲載種別：研究論文（学術雑誌）  

DOI： 10.1541/ieejeiss.134.1071

J-GLOBAL

掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.11648/j.acis.20130106.11

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1109/CLEOPR.2013.6600270

掲載種別：研究論文（学術雑誌）  

We demonstrated the stimulation of neurons at a single-cell level in cultured neuronal network by a focused femtosecond laser. When the femtosecond laser was focused on a neuron loaded with a fluorescent calcium indicator, the fluorescence intensity immediately increased at the laser spot, suggesting that intracellular Ca2+ increases in the neuronal cell due to the femtosecond laser irradiation. The probability of Ca2+ elevation at the laser spot depended on the average laser power, irradiation time, and position of the focal point along the optical axis, indicating that the femtosecond laser activates neurons because of multiphoton absorption. Moreover, after laser irradiation of a single neuron cultured on multielectrode arrays, the evoked electrical activity of the neurons was demonstrated by electrophysiological systems, which concluded that the focused femtosecond laser could achieve stimulating a single neuron in a neuronal network with high spatial and temporal resolution. © Springer-Verlag 2012.

DOI： 10.1007/s00339-012-7137-6

その他URL： http://orcid.org/0000-0002-0289-4680

掲載種別：研究論文（学術雑誌）  

DOI： 10.1364/jsap.2013.16p_d5_8

掲載種別：研究論文（国際会議プロシーディングス）  

We demonstrated laser manipulation of intracellular molecular dynamics in neurons to realize artificial control toward modulating synaptic transmission in a neuronal network. The optical trapping and assembling dynamics of synaptic vesicles and neural cell adhesion molecules in neurons was revealed by fluorescence analysis. © 2013 IEEE.

DOI： 10.1109/CLEOPR.2013.6600270

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1038/ncomms2233

PubMed

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1143/JJAP.51.06FK10

J-GLOBAL

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1071/CH12127

掲載種別：研究論文（学術雑誌）  

In circuit theory, it is well known that a linear feedback shift register (LFSR) circuit generates pseudorandom bit sequences (PRBS), including an M-sequence with the maximum period of length. In this study, we tried to detect M-sequences known as a pseudorandom sequence generated by the LFSR circuit from time series patterns of stimulated action potentials. Stimulated action potentials were recorded from dissociated cultures of hippocampal neurons grown on a multielectrode array. We could find several M-sequences from a 3-stage LFSR circuit (M3). These results show the possibility of assembling LFSR circuits or its equivalent ones in a neuronal network. However, since the M3 pattern was composed of only four spike intervals, the possibility of an accidental detection was not zero. Then, we detected M-sequences from random spike sequences which were not generated from an LFSR circuit and compare the result with the number of M-sequences from the originally observed raster data. As a result, a significant difference was confirmed: a greater number of 01 reversed the 3-stage M-sequences occurred than would have accidentally be detected. This result suggests that some LFSR equivalent circuits are assembled in neuronal networks. © Copyright 2012 Yoshi Nishitani et al.

DOI： 10.1155/2012/862579

PubMed

掲載種別：研究論文（学術雑誌）  

Electrifying! A device based on carbon nanotubes wrapped with poly(3-hexylthiophene) (and dispersed in poly(dimethylsiloxane)) sheets can effectively convert laser light into thermal energy and subsequently to electricity. The converter is flexible and extremely compact (see picture), and can be manipulated by using a laser that functions in the wavelength range that can be transmitted through living tissue. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

DOI： 10.1002/anie.201106136

PubMed

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1063/1.3579191

掲載種別：研究論文（学術雑誌）  

We have developed a neuro-robot-hybrid system using a living neuronal network and a miniature moving robot. The living network of rat hippocampal neurons can distinguish patterns of action potentials evoked by different inputs, suggesting that a cultured neuronal network can represent particular states as symbols. We used a Khepera II robot and a robot made using a LEGO mindstorm NXT kit to interface with a living neuronal network and the outer world. We call the system 'vitroid'. Vitroid has living neurons, a robot body, and direct coupling controllers to interface the neurons with the robot. Vitroid was able to perform obstacle avoidance behaviour with premised control rule sets. Copyright © 2011 Inderscience Enterprises Ltd.

DOI： 10.1504/IJMMS.2011.039264

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1016/j.neures.2011.07.894

掲載種別：研究論文（学術雑誌）  

We propose and demonstrate micro-channel fabrication by femtosecond-laser processing to arrange neuronal cells on multi-electrode arrays (MEAs). When neuronal cells were seeded in the micro-channels on MEAs, they elongated their neurites along the channel and finally formed the network patterned on MEAs. The spontaneous electrical activity of the neuronal networks on MEAs was evaluated by using electrophysiological systems, indicating that patterned network was functionally activated along the channels. The present method is applicable to analyze network dynamics of living neuronal cells patterned artificially. © 2010 Springer-Verlag.

DOI： 10.1007/s00339-010-5836-4

CiNii Article

掲載種別：研究論文（学術雑誌）  

A method including surface silanization, phase transfer and self-assembly, and SiO2 shell growth has been developed to incorporate multiple hydrophobic CdSe/ZnS nanocrystals into SiO2 beads where they are well suited for bio-application due to their high brightness, less-cytotoxic, and non-blinking nature. © 2010 The Royal Society of Chemistry.

DOI： 10.1039/c002243h

PubMed

CiNii Article

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1016/j.neures.2010.07.1034

掲載種別：研究論文（国際会議プロシーディングス）  

The rat hippocampal neurons were cultured on a dish with 64 planer micro electrodes array. Neurons reorganized a functional network, and an external inputs form outer world elicited a reproducible, particular spatiotemporal pattern of evoked action potentials. The patterns were not completely uniform for repeptive stimulation but varied slightly. We previously reported that dissociated rat hippocampal neurons possessed hysterical function in its network dynamics. The spatio-temporal electrical activity of the living neuronal network evoked by paired stimulation is quite different from one evoked by a single stimulation, suggested that the network can "memorize" an existence of precedent stimulation. In this report, the feature of this type of network hysteresis was investigated and the hysteresis was kept for at least 1s and not kept for 10s. In addition, this hysteresis was remarkable only in aged cultures with matured complex network. Network hysteresis depends on internal state of the network, generated by the autonomous activity in self-organized networks. ©2010 IEEE.

DOI： 10.1109/MHS.2010.5669566

掲載種別：研究論文（学術雑誌）  

An all-wet femtosecond laser microprocessing technique was utilized for patterning and cutting functional network of living neuronal cells on a multi-electrode dish (MED). The neuronal cells cultured on a source substrate were transferred onto an electrode in a MED probe in solution by utilizing a femtosecond laser-induced impulsive force and a pattern of neuronal cells were formed on the MED probe. The cellular activity of the detached neurons was supported that neurites could be regenerated around the electrodes. As another processing method, the neurons stretching between electrodes were selectively cut by the direct femtosecond laser irradiation and the spontaneous electrical activity of the neuronal network was evaluated. While the spontaneous action potentials of neurons were synchronized before the cutting, the synchronization disappeared after the cutting, indicating that the neuronal network is locally disconnected by the laser cutting. The present method is applicable to artificial reconstruction of living neuronal network. © 2008 Springer-Verlag.

DOI： 10.1007/s00339-008-4655-3

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1097/WNR.0b013e3282fdf6b3

PubMed

掲載種別：研究論文（国際会議プロシーディングス）  

Rat hippocampal neurons organized complex networks on a culture dish which has 64 planar microelectrodes and the spontaneous action potentials were frequently observed. The living neuronal network was able to distinguish patterns of action potentials evoked by different inputs, suggesting that a cultured neuronal network can represent and process particular states as symbols. We use a Khepera II robot and a robot made by LEGO mindstorm NXT kit as a robot body for interfacing with a living neuronal network and the outer world. We call the system "Vitroid". Vitroid has the living neurons, robot body, and direct coupling type of controllers to interface neurons with the robot. We succeeded in performing obstacle avoidance behavior with premised control rule sets. Using self-tuning fuzzy reasoning, we associated a distinct spatial pattern of electrical activity with a particular phenomenon in the outside of the culture dish. © 2008 IEEE.

DOI： 10.1109/ICMA.2008.4798783

掲載種別：研究論文（学術雑誌）   共著区分：共著  

We investigated laser-induced phase transition dynamics of μm sized single poly(N-isopropylacrylamide) hydrogel particles in water. Single poly(N--isopropylacrylamide) gel particles labeled with a polarity-sensitive fluorescent probe monomer were optically trapped by a focused laser beam and its fluorescence dynamics was analyzed. The fluorescence intensity of trapped single gel particles was increased with the trapping laser power, while the fluorescence peak wavelength was not changed. Temperature-induced changes of fluorescence properties of the single particle were confirmed to be similar to those of the bulk solution. These behaviors are well interpreted by considering that the fluorescence intensity and fluorescence peak reflect local interactions between the fluorescent probe and attaching (bound) water molecules and effective polarity determined by (free) water content in the particle, respectively. A change in the fluorescence peak wavelength after laser trapping was followed and its blue-shift was confirmed to occur within a few hundreds seconds, indicating that a single gel particle gradually attains to a globular state on this timescale, expelling initially free water molecules and then bound ones.

掲載種別：研究論文（学術雑誌）   共著区分：共著  

その他URL： http://dblp.uni-trier.de/db/journals/jrm/jrm19.html#journals/jrm/KudohHKTH07

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1016/j.neures.2007.06.1433

掲載種別：研究論文（国際会議プロシーディングス）   共著区分：共著  

DOI： 10.1109/MHS.2007.4420824

掲載種別：研究論文（学術雑誌）   共著区分：共著  

We propose and demonstrate the enhancement of the biased diffusion of dye-doped nanoparticles using resonance and nonresonance laser beams. The Brownian motion of nanoparticles in a laser focus is investigated by fluorescence correlation spectroscopy (PCS) and the time variation in fluorescence intensity. From the analysis of autocorrelation functions, it is demonstrated that the difference between the transit times of nanoparticles in the focal spot with and without resonance laser irradiation increases ∼7-fold by the simultaneous irradiation of a near-infrared laser. This method is applicable to the selective optical manipulation of dye-stained nanomaterials and biomolecules in solution. © 2006 The Japan Society of Applied Physics.

DOI： 10.1143/JJAP.45.L453

掲載種別：研究論文（学術雑誌）  

When laser beam was focused into nanoparticle suspensions, nanoparticles can be trapped in the focal spot due to optical gradient force. Here we report the optical trapping and fluorescence analysis of poly(N-isopropylacrylamide) (PNIPAM) and its related polymer microgel particles which were labeled with 4-N-(2-acryloyloxyethyl)-N-methylamino-7-N,N-dimethylaminosulfonyl-2,1, 3-benzoxadiazole (DBD-AE) dispersed in water. The DBD-AE labeled PNIPAM microgel particles were trapped at the focal point by irradiation with cw-Nd 3+:YAG laser (λ = 1064 nm) in water and the fluorescence intensity of the DBD-AE labeled PNIPAM microgel particles excited by diode laser (λ = 405 nm) increased stepwise. We succeeded to fluorescence analysis of trapped single microgel particle.

掲載種別：研究論文（学術雑誌）   共著区分：共著  

DOI： 10.1103/PhysRevE.72.021408

掲載種別：研究論文（学術雑誌）  

We report in situ observation of cluster growth of nanoparticles confined in an optical trapping potential by means of fluorescence correlation spectroscopy. When an optical trapping force caused by a highly focused laser beam acts on nanoparticle suspensions, the number of nanoparticles increases and an assembly can be formed at the focal spot. The decay times of fluorescence autocorrelation curves were investigated as a function of the irradiation time of the laser beam and the laser power. In the initial stage of the optical assembling, the decay time increases with the irradiation time of the laser beam. On the other hand, in the later stage, a decrease of the decay time was observed. This behavior is explained successfully by using two models of Brownian motion under weak and strong optical trapping. It was revealed that trapping and clustering of nanoparticles proceed simultaneously and clusters confined in the focal spot make larger aggregates spontaneously. © 2005 The American Physical Society.

DOI： 10.1103/PhysRevE.72.021408

PubMed

掲載種別：研究論文（学術雑誌）  

Reverse transcription of the HIV-1 RNA genome involves several complex nucleic acid rearrangement steps that are catalyzed by the HIV-1 nucleocapsid protein (NC), including for example, the annealing of the transactivation response (TAR) region of the viral RNA to the complementary region (TAR DNA) in minus-strand strong-stop DNA. We report herein single-molecule fluorescence resonance energy transfer measurements on single immobilized TAR DNA hairpins and hairpin mutants complexed with NC (i.e., TAR DNA/NC). Using this approach we have explored the conformational distribution and dynamics of the hairpins in the presence and absence of NC protein. The data demonstrate that NC shifts the equilibrium secondary structure of TAR DNA hairpins from a fully "closed" conformation to essentially one specific "partially open" conformation. In this specific conformation, the two terminal stems are "open" or unwound and the other stems are closed. This partially open conformation is arguably a key TAR DNA intermediate in the NC-induced annealing mechanism of TAR DNA. Copyright 2004 Biophysical Society

DOI： 10.1529/biophysj.104.043083

PubMed

掲載種別：研究論文（学術雑誌）  

When a laser beam is focused into colloidal nanoparticle suspensions, a number of nanoparticles can be confined in the focal spot due to an optical gradient force. To reveal the assembling dynamics of polymer nanoparticles, the assembling process was investigated by analyzing the time evolution of the fluorescence intensity of the nanoparticles. In a dilute suspension of 100-nm-sized particles, a stepwise increase of the fluorescence intensity corresponding to a trapped single nanoparticle was observed. Statistical analysis revealed that the initial assembling rate of nanoparticles was proportional to the laser power and concentration of particle suspensions as expected from the diffusion equation. In 40-nm-sized particle suspensions, blinking profiles of fluorescence intensity were obtained, in which 2–3 particles were simultaneously trapped and then escaped from the focal point. It is considered from statistical analyses and two-dimensional Monte Carlo simulations that this assembling phenomenon is attributable to cluster formation assisted by optical trapping. © 2004 The American Physical Society.

DOI： 10.1103/PhysRevE.70.061410

掲載種別：記事・総説・解説・論説等（学術雑誌）   共著区分：単著  

掲載種別：記事・総説・解説・論説等（学術雑誌）  

CiNii Article

掲載種別：記事・総説・解説・論説等（学術雑誌）   共著区分：単著  

CiNii Article

掲載種別：記事・総説・解説・論説等（学術雑誌）   共著区分：単著  

CiNii Article

J-GLOBAL

掲載種別：記事・総説・解説・論説等（学術雑誌）   共著区分：単著  

掲載種別：記事・総説・解説・論説等（学術雑誌）  

掲載種別：記事・総説・解説・論説等（学術雑誌）  

掲載種別：記事・総説・解説・論説等（学術雑誌）  

J-GLOBAL

掲載種別：記事・総説・解説・論説等（学術雑誌）  

J-GLOBAL

掲載種別：記事・総説・解説・論説等（学術雑誌）  

J-GLOBAL

掲載種別：記事・総説・解説・論説等（学術雑誌）   共著区分：単著  

CiNii Article

掲載種別：記事・総説・解説・論説等（学術雑誌）  

In circuit theory it is well known that loop circuit with a feedback link generates a pseudo-random sequence including an M-sequence with maximum period length. On the other hand, it remains unclear how memory is stored in neural circuits of the human brain. We propose that M-sequence composes temporal independent basis functions in brain neural network for communication and memory storage. We have already shown its feasibility by computer simulations that show a loop circuit can be copied to another area by back-propagation leaning algorithm; this is a key function of brain intelligence, which includes functions such as memory, association, reasoning, and abstraction. We found M-sequence responses in the instantaneous firing rates from cultured neural networks of published data and our own data, which suggest the existence of loop circuits with a feedback link composed of 3 to 5 neuron cells. Analyzing the time sequence of spike intervals of cultured neural network with the "auto mutual-information function," we also find evidence that suggests the existence of loop circuits with a feedback link composed of 3, 4 neurons.

CiNii Article

掲載種別：記事・総説・解説・論説等（学術雑誌）  

CiNii Article

J-GLOBAL

DOI： 10.2142/biophys.52.S26_4

我々は脳構成論の立場から記憶の基本はループ回路であると考え,それらの間で時間的疑似直交パルス系列による通信により統一的な形で情報の伝達,転写,連想,抽象化ができると考えている.我々の従来研究においては,コンピュータシミュレーションにより遠隔部位間において物理的実現可能な形で自己組織的に系列情報の伝達を介してループ回路の転写ができることを確認している.しかし,実際の脳神経回路における記憶の伝送並びに転写の機能については実証されていない.本研究では,ラット培養神経回路網の神経活動電位の刺激応答より,素子数3のフィードバックつきシフトレジスタ回路の出力に相当する疑似ランダム系列で脳内記憶の読み出しが行われている可能性を確認した.

掲載種別：記事・総説・解説・論説等（学術雑誌）  

掲載種別：記事・総説・解説・論説等（学術雑誌）  

CiNii Article

J-GLOBAL

量子ドット(QD)は,明るい蛍光を発し、その発光波長を粒径や組成で制御できる.また,有機色素よりも耐光性が良いため,新規なバイオ用高輝度蛍光試薬として注目されている.蛍光性のQDは溶液法で得られるが,そのままでは不安定で劣化しやすい.そのため我々は,常温常圧で溶液反応によりガラスを合成できるゾル-ゲル法を用いて,InPやCdSe等のQDを微小なガラスビーズ(粒径数十nm程度)中に分散した安定な水分散性蛍光体を作製した.QD分散ガラスビーズは,バイオ用の緩衝液中に希釈した際に,市販ポリマーコートQDよりも格段に高い安定性と耐光性を示した.さらに,このガラスビーズは貪食作用で生きた培養神経細胞に導入でき,細胞形状の高分解能イメージングが可能であった.

掲載種別：記事・総説・解説・論説等（学術雑誌）  

CiNii Article

掲載種別：記事・総説・解説・論説等（学術雑誌）  

The intense electromagnetic field produced by a focused laser beam attracts microparticles, dispersed in liquid, into the focal spot. This is known as optical trapping and used to manipulate microparticles dispersed in liquid. If the size of the particles is much smaller than that of the focal spot, i.e. the order is of wavelength, a number of particles are trapped in the focal spot. This means that the focal spot of the laser beam acts as a microcage for nanoparticles and the confined nanoparticles form a microassembly. Nanoparticles are attractive materials for their characteristic chemical, physical, and optical properties. We have studied "optical assembly" of nanoparticles and found the following unique properties. (1) By a single particle counting measurement, it was revealed that the assembling process of polystyrene nanoparticles is dependent on laser power and concentration. (2) It was demonstrated that the assembly structure and optical properties of gold-nanoparticles can be controlled by optical force.

DOI： 10.1380/jsssj.26.681

CiNii Article

会議種別：ポスター発表  

開催地：名古屋国際会議場、愛知県名古屋市  

会議種別：ポスター発表  

開催地：名古屋国際会議場、愛知県名古屋市  

会議種別：ポスター発表  

会議種別：ポスター発表  

開催地：Washington, D.C., USA  

会議種別：ポスター発表  

開催地：神戸大学、兵庫県神戸市  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

開催地：静岡県浜松市  

会議種別：口頭発表（一般）  

開催地：熊本城ホール他、熊本県熊本市  

会議種別：口頭発表（一般）  

開催地：石川県金沢市  

会議種別：口頭発表（一般）  

開催地：熊本城ホール他、熊本県熊本市  

会議種別：口頭発表（一般）  

開催地：熊本城ホール他、熊本県熊本市  

会議種別：口頭発表（一般）  

開催地：熊本城ホール他、熊本県熊本市  

会議種別：口頭発表（一般）  

開催地：熊本城ホール他、熊本県熊本市  

会議種別：口頭発表（一般）  

開催地：熊本城ホール他、熊本県熊本市  

会議種別：口頭発表（一般）  

開催地：石川県金沢市  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

開催地：宮城県仙台市  

会議種別：ポスター発表  

開催地：宮城県仙台市  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

開催地：大阪公立大学、大阪府大阪市  

会議種別：ポスター発表  

開催地：Sapporo, Japan  

会議種別：口頭発表（一般）  

開催地：Sapporo, Japan  

会議種別：ポスター発表  

開催地：Sapporo, Japan  

会議種別：口頭発表（招待・特別）  

会議種別：ポスター発表  

開催地：兵庫県淡路市  

会議種別：ポスター発表  

開催地：兵庫県淡路市  

会議種別：ポスター発表  

開催地：名古屋国際会議場、愛知県名古屋市  

会議種別：口頭発表（一般）  

開催地：Yokohama, Japan  

会議種別：口頭発表（一般）  

開催地：Yokohama, Japan  

会議種別：口頭発表（一般）  

開催地：上智大学、東京都千代田区  

会議種別：口頭発表（一般）  

開催地：上智大学、東京都千代田区  

会議種別：口頭発表（一般）  

開催地：上智大学、東京都千代田区  

会議種別：口頭発表（一般）  

開催地：上智大学、東京都千代田区  

会議種別：口頭発表（一般）  

開催地：上智大学、東京都千代田区  

会議種別：ポスター発表  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

開催地：大阪公立大、大阪府大阪市  

会議種別：口頭発表（招待・特別）  

開催地：大阪公立大学、大阪府大阪市  

会議種別：口頭発表（招待・特別）  

開催地：大阪大学、大阪府豊中市  

会議種別：口頭発表（一般）  

開催地：Adelaide, Australia  

会議種別：ポスター発表  

開催地：Adelaide, Australia  

会議種別：口頭発表（一般）  

開催地：兵庫県神戸市  

会議種別：口頭発表（招待・特別）  

開催地：Tokushima, Japan  

会議種別：ポスター発表  

開催地：Tokushima, Japan  

会議種別：ポスター発表  

開催地：Tokushima Univ., Tokushima  

会議種別：口頭発表（招待・特別）  

開催地：オンライン  

会議種別：ポスター発表  

開催地：関西学院大学、兵庫県西宮市  

会議種別：ポスター発表  

開催地：大阪大学、大阪府吹田市  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

開催地：大阪大学、大阪府吹田市  

会議種別：ポスター発表  

開催地：函館アリーナ、北海道函館市  

会議種別：ポスター発表  

開催地：函館アリーナ、北海道函館市  

会議種別：口頭発表（一般）  

開催地：東北大学、宮城県仙台市  

会議種別：口頭発表（一般）  

開催地：東北大学、宮城県仙台市  

会議種別：口頭発表（一般）  

開催地：東北大学、宮城県仙台市  

会議種別：口頭発表（一般）  

開催地：東北大学、宮城県仙台市  

会議種別：口頭発表（一般）  

開催地：Bayreuth, Germany  

会議種別：口頭発表（招待・特別）  

開催地：オンライン  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

開催地：Sapporo, Japan  

会議種別：口頭発表（一般）  

開催地：Sapporo, Hokkaido  

会議種別：口頭発表（一般）  

開催地：Sapporo, Japan  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

開催地：東京都江東区  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

開催地：Yokohama, Japan  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

会議種別：ポスター発表  

会議種別：ポスター発表  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：ポスター発表  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：ポスター発表  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

開催地：Yokohama, Japan  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：ポスター発表  

開催地：Osaka, Japan  

会議種別：ポスター発表  

開催地：Osaka  

会議種別：ポスター発表  

開催地：Ikuta Shrine Hall, Kobe, Japan  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（招待・特別）  

開催地：Awaji Yumebutai International Conference Center, Awaji Island, Japan  

会議種別：ポスター発表  

開催地：大阪市立大学、大阪府大阪市  

会議種別：ポスター発表  

開催地：Osaka, Japan  

会議種別：口頭発表（招待・特別）  

開催地：名古屋大学、愛知県名古屋市  

会議種別：口頭発表（一般）  

開催地：名古屋大学、愛知県名古屋市  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

開催地：Awaji Yumebutai International Conference Center, Awaji Island, Hyogo  

会議種別：口頭発表（一般）  

開催地：Yokohama, Japan  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

開催地：大阪府立大学  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

© 2018 OSA - The Optical Society. All rights reserved. Fluorescent imaging is a powerful technique to reveal how target cells or biomolecules work in biological tissues and cells. So far, organic dyes, fluorescent proteins, and quantum dots have been developed and widely used as a fluorescent probe. However, these fluorescent probes do not work well in certain conditions: they have cytotoxicity and steric hindrance due to inclusion of harmful atoms and/or their sizes. Hence, metal nanoclusters, that are composed of several metal atoms and emit fluorescence owing to quantum size effect, have been anticipated as a newly categorized fluorescent probe. Since the fluorescent wavelength depends on their sizes, it is possible to control the fluorescent wavelength by adjusting the number of composed atoms [1].

会議種別：口頭発表（招待・特別）  

開催地：Tohoku University  

会議種別：口頭発表（招待・特別）  

開催地：大阪大学  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）  

開催地：大阪府立大学  

会議種別：口頭発表（招待・特別）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

知能の基本原理を解明することにより,画像認知の高度化・知能化・質的向上を図ることができる.しかしながら,神経回路網の基本機能は解明されていない.本研究では,神経回路網の基本機能として情報伝搬の仕組みの一端を明らかにする.とくに培養神経とマルチ電極を用いた情報伝搬の可視化について記す.M系列ファミリーなどランダム的符号を検出することにより,その移動量が定量化できる.また,2Dメッシュ状神経回路網モデルにより,符号スペクトルがシミュレートできることを示す.

会議種別：口頭発表（一般）  

© 2015 SPIE. Molecular dynamics at synaptic terminals in neuronal cells is essential for synaptic plasticity and subsequent modulation of cellular functions in a neuronal network. For realizing artificial control of living neuronal network, we demonstrate laser-induced perturbation into molecular dynamics in the neuronal cells. The optical trapping of cellular molecules such as synaptic vesicles or neural cell adhesion molecules labeled with quantum dots was evaluated by fluorescence imaging and fluorescence correlation spectroscopy. The trapping and assembling dynamics was revealed that the molecular motion was constrained at the focal spot of a focused laser beam due to optical trapping force. Our method has a potential to manipulate synaptic transmission at single synapse level.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

Neuron is a simple computational element with rough function, e.g. it cannot receive spikes between refractory period of after it fires. Besides this, its parameters fluctuate time to time. However, as a neuron network they can work intellectually. This gap is an big problem to be solved not only from physiological point of view but also from computer science. We detected pseudo random sequences including M-sequence family in spike trains of cultured neuron network significantly more than by chance. This gave code flow map on multi-electrode array dishes (MED-P515A, Alpha MED Scientific, Kadoma, Osaka, Japan) with 8 × 8 planar microelectrodes. Each electrode catches spikes from several neurons. Conventionally these spike trains are sorted to extract spikes from respective single neuron. Unfortunately but fortunately, however, we obtained mixed neuron spike trains, and by analyzing these, we could find principle of intelligent neuronal network processing.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

We demonstrated laser manipulation of intracellular molecular dynamics in neurons to realize artificial control toward modulating synaptic transmission in a neuronal network. The optical trapping and assembling dynamics of synaptic vesicles and neural cell adhesion molecules in neurons was revealed by fluorescence analysis. © 2013 IEEE.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

We have already shown its feasibility by computer simulations that show a loop circuit can be copied to another area by back-propagation leaning algorithm; this is a key function of brain intelligence, which includes functions such as memory, association, reasoning, and abstraction. We also have found M-sequences in spike trains of cultured neuronal networks. In this paper, we report that we found family or fragment of M-sequence responses also in the instantaneous firing rates (PSTH's) from cultured neural networks of published data and our own data, which suggest the existence of loop circuits with a feedback link composed of 3 to 5 neuron cells or equivalent circuits. © 2012 AICIT.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

我々は脳構成論の立場から記憶の基本はフィードバック付きループ回路(FSR)であり,この回路で生成されるM系列により記憶の伝送,転写という脳内情報処理の基本機能が制御されているのではないかと考えている.本研究では,その生理学的実証に向けて,ラット培養神経回路網の刺激スパイク列の時系列パターンを解析し,M系列の検出を試みた.その結果,素子数3のLFSRで生成されるM系列が検出された.また,脳内では計算機のようにクロック周期の統制がなく,出力されるM系列も,ビット幅のゆらぎ(margin)がある可能性を考慮し,marginとM系列検出数の相関を検定した.その結果正の相関が確認された.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

我々は脳構成論の立場から記憶の基本はループ回路であると考え,それらの間で時間的疑似直交パルス系列による通信により統一的な形で情報の伝達,転写,連想,抽象化ができると考えている.我々の従来研究においては,コンピュータシミュレーションにより遠隔部位間において物理的実現可能な形で自己組織的に系列情報の伝達を介してループ回路の転写ができることを確認している.しかし,実際の脳神経回路における記憶の伝送並びに転写の機能については実証されていない.本研究では,ラット培養神経回路網の神経活動電位の刺激応答より,素子数3のフィードバックつきシフトレジスタ回路の出力に相当する疑似ランダム系列で脳内記憶の読み出しが行われている可能性を確認した.

会議種別：口頭発表（一般）  

The rat hippocampal neurons were cultured on a dish with 64 planer micro electrodes array. Neurons reorganized a functional network, and an external inputs form outer world elicited a reproducible, particular spatiotemporal pattern of evoked action potentials. The patterns were not completely uniform for repeptive stimulation but varied slightly. We previously reported that dissociated rat hippocampal neurons possessed hysterical function in its network dynamics. The spatio-temporal electrical activity of the living neuronal network evoked by paired stimulation is quite different from one evoked by a single stimulation, suggested that the network can "memorize" an existence of precedent stimulation. In this report, the feature of this type of network hysteresis was investigated and the hysteresis was kept for at least 1s and not kept for 10s. In addition, this hysteresis was remarkable only in aged cultures with matured complex network. Network hysteresis depends on internal state of the network, generated by the autonomous activity in self-organized networks. ©2010 IEEE.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

量子ドット(QD)は,明るい蛍光を発し、その発光波長を粒径や組成で制御できる.また,有機色素よりも耐光性が良いため,新規なバイオ用高輝度蛍光試薬として注目されている.蛍光性のQDは溶液法で得られるが,そのままでは不安定で劣化しやすい.そのため我々は,常温常圧で溶液反応によりガラスを合成できるゾル-ゲル法を用いて,InPやCdSe等のQDを微小なガラスビーズ(粒径数十nm程度)中に分散した安定な水分散性蛍光体を作製した.QD分散ガラスビーズは,バイオ用の緩衝液中に希釈した際に,市販ポリマーコートQDよりも格段に高い安定性と耐光性を示した.さらに,このガラスビーズは貪食作用で生きた培養神経細胞に導入でき,細胞形状の高分解能イメージングが可能であった.

会議種別：口頭発表（一般）  

量子ドット(QD)は,明るい蛍光を発し、その発光波長を粒径や組成で制御できる.また,有機色素よりも耐光性が良いため,新規なバイオ用高輝度蛍光試薬として注目されている.蛍光性のQDは溶液法で得られるが,そのままでは不安定で劣化しやすい.そのため我々は,常温常圧で溶液反応によりガラスを合成できるゾル-ゲル法を用いて,InPやCdSe等のQDを微小なガラスビーズ(粒径数十nm程度)中に分散した安定な水分散性蛍光体を作製した.QD分散ガラスビーズは,バイオ用の緩衝液中に希釈した際に,市販ポリマーコートQDよりも格段に高い安定性と耐光性を示した.さらに,このガラスビーズは貪食作用で生きた培養神経細胞に導入でき,細胞形状の高分解能イメージングが可能であった.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

Rat hippocampal neurons organized complex networks on a culture dish which has 64 planar microelectrodes and the spontaneous action potentials were frequently observed. The living neuronal network was able to distinguish patterns of action potentials evoked by different inputs, suggesting that a cultured neuronal network can represent and process particular states as symbols. We use a Khepera II robot and a robot made by LEGO mindstorm NXT kit as a robot body for interfacing with a living neuronal network and the outer world. We call the system "Vitroid". Vitroid has the living neurons, robot body, and direct coupling type of controllers to interface neurons with the robot. We succeeded in performing obstacle avoidance behavior with premised control rule sets. Using self-tuning fuzzy reasoning, we associated a distinct spatial pattern of electrical activity with a particular phenomenon in the outside of the culture dish. © 2008 IEEE.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

Rat hippocampal neurons organized complex networks on a culture dish which has 64 planner microelectrodes and action potentials of neurons were recorded from an individual electrode. MED64 system, one of multi site recording systems for extracellular action potential was used for recording network activities of living neuronal networks and for applying inputs from outer world to the network. Neurons reconstructed complicated networks along culture days, and a spatio-temporal pattern of spontaneous action potentials was drastically changed after transient high-frequency bursting activities (HFB) . After HFB, spatial distribution of spontaneous action potentials changed to heterogeneous one. We designed programmable multisite stimulation head amplifier, and analysis of evoked action potentials induced by the stimulator confirmed that there are some hub-like structure which has many inputs from other neurons. In addition we are developing "biomodeling system", in which living neuronal network connected to moving robot. ©2007 IEEE.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

When laser beam was focused into nanoparticle suspensions, nanoparticles can be trapped in the focal spot due to optical gradient force. Here we report the optical trapping and fluorescence analysis of poly(N-isopropylacrylamide) (PNIPAM) and its related polymer microgel particles which were labeled with 4-N-(2-acryloyloxyethyl)-N-methylamino-7-N,N-dimethylaminosulfonyl-2,1, 3-benzoxadiazole (DBD-AE) dispersed in water. The DBD-AE labeled PNIPAM microgel particles were trapped at the focal point by irradiation with cw-Nd 3+:YAG laser (λ = 1064 nm) in water and the fluorescence intensity of the DBD-AE labeled PNIPAM microgel particles excited by diode laser (λ = 405 nm) increased stepwise. We succeeded to fluorescence analysis of trapped single microgel particle.

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（一般）  

会議種別：口頭発表（招待・特別）