634 results on '"Kumano, H."'
Search Results
202. Exploring Spontaneous Simultaneous Photon-pair Generation in Semiconductors.
- Author
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Suemune, I., Asano, Y., Tanaka, K., Inoue, R., Takayanagi, H., Sasakura, H., Akazaki, T., and Kumano, H.
- Subjects
SEMICONDUCTORS ,PHOTONS ,LIGHT emitting diodes ,EXCITON theory ,ELECTROLUMINESCENT devices - Abstract
Potential of generating entangled photon pairs from a Cooper-pair light emitting diode is demonstrated with experimental and theoretical studies. [ABSTRACT FROM AUTHOR]
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- 2011
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203. Electron-Cooper-pair operated long-wavelength light emitting diodes.
- Author
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Sasakura, H., Tanaka, K., Huh, J.-H., Akazaki, T., Kumano, H., and Suemune, I.
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- 2010
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204. Exciton-phonon interactions observed in blue emission band in Te-delta-doped ZnSe.
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Jo, M., Hayashi, Y., Kumano, H., and Suemune, I.
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EXCITON theory , *PHONONS , *TELLURIUM , *ZINC selenide , *POISSON distribution , *LUMINESCENCE , *PHOTOLUMINESCENCE - Abstract
Photoluminescence (PL) in the blue wavelength region originating from a no-phonon (NP) transition at 2.734 eV and longitudinal optical (LO) phonon sidebands of Te isoelectronic centers (ICs) were clearly resolved after thermal annealing by δ-doping of Te in ZnSe layers. Broad luminescence (conventionally called the S1 band) had been previously observed in this region (i.e., around 2.65 eV). The PL intensities of the NP line and the phonon replicas followed a Poisson distribution with a mean phonon number (Huang–Rhys factor) of S∼1.1. This indicates that the broadening of the 2.65 eV emission band is due to the superposition of the NP lines and their LO phonon replicas originating from the Te ICs with slight variations in their transition energies. The origin of the luminescence is discussed in relation to linearly polarized PL measurements. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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205. Surface-emitting stimulated emission in high-quality ZnO thin films.
- Author
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Q.#Zhang, X., Suemune, Ikuo, Kumano, H., Wang, J., Huang, S. H., and S. H. Huang
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SPECTRUM analysis , *SCATTERING (Physics) , *EUCLID'S elements , *CRYSTAL growth , *SURFACE coatings , *THICK films , *THIN films - Abstract
High-quality ZnO thin films were grown by plasma-enhanced molecular-beam epitaxy on sapphire substrates. Three excitonic transitions associated with the valence bands A, B, and C were clearly revealed in the reflectance spectrum measured at 33 K. This result indicates that the ZnO thin films have the wurtzite crystalline structure. The emission spectra were measured with backscattering geometry at room temperature. When the excitation exceeded a certain value, linewidth narrowing, nonlinear rise of emission intensity, and the shortening of the carrier lifetime were clearly observed and these demonstrate the onset of stimulated emission. Together with the ZnO thickness dependence, we conclude that the observation of a stimulated emission in a direction perpendicular to the film surface is predominantly due to scattering of the in-plane stimulated emission by slightly remaining surface undulations in the ZnO films. [ABSTRACT FROM AUTHOR]
- Published
- 2004
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206. InAs-quantum-dots-based light emitting diodes with GaNAs strain-compensating layers.
- Author
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Kurimoto, M., Ganapathy, S., Zhang, X.Q., Uesugi, K., Kumano, H., and Suemune, I.
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- 2002
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207. Changes of immunoregulatory cells associated with psychological stress and humor.
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Kamei, T, Kumano, H, and Masumura, S
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PSYCHOLOGICAL stress , *COMEDY , *T cells , *HEALTH - Abstract
Investigates the influence of psychological stress or humor on T-cell subset percentages before and after watching a comedy video. Changes of immunoregulatory cells associated with psychological stress and humor; Association of the natural cell activity with T-cell subsets; Decrease in killer cell activity after watching the comedy video.
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- 1999
208. Growth of zincblende [formula omitted] superlattices and their heterointerface properties
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Suemune, I., Obinata, T., Uesugi, K., Suzuki, H., Kumano, H., Nashiki, H., and Nakahara, J.
- Published
- 1997
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209. Fiber-coupled pillar array as a highly pure and stable single-photon source.
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Odashima, S., Sasakura, H., Nakajima, H., and Kumano, H.
- Subjects
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QUANTUM dots , *INDIUM arsenide , *LIQUID helium , *PHOTONS , *AUTOCORRELATION (Statistics) - Abstract
A highly pure and stable single-photon source is prepared that comprises a well-designed pillar array, in which each pillar contains only a few InAs quantum dots. A nano-pillar in this array is in direct contact with a fiber end surface and cooled in a liquid-He bath. Auto-correlation measurements show that this source provides an average g(2)(0) value of 0.0174 in the measured excitationpower range. This photon source and fiber coupling are quite rigid against external disturbances such as cooling-heating cycles and vibration, with long-term stability. [ABSTRACT FROM AUTHOR]
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- 2017
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210. Stuck Valve Leaflet Detected by Intraoperative Transesophageal Echocardiography
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Kumano, H., Suehiro, S., Shibata, T., Hattori, K., and Kinoshita, H.
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- 1999
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211. Luminescence study on evolution from Te isoelectronic centers to type-II ZnTe quantum dots grown by metalorganic molecular-beam epitaxy
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Jo, M., Endo, M., Kumano, H., and Suemune, I.
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TELLURIUM , *LUMINESCENCE , *QUANTUM dots , *MOLECULAR beam epitaxy - Abstract
Abstract: Isoelectronically substitutional material systems are proposed as offering a unique possibility to study the physics of different regimes from single isoelectronic centers (ICs) to self-assembled quantum dots (QDs) within the same material combinations. Luminescence evolution of ZnSe:Te system were investigated as such isoelectronically substitutional system. A successive change in the spectral dominance of luminescence with increasing ZnTe layer thickness indicates the evolution from ICs to QDs in ZnSe:Te system. [Copyright &y& Elsevier]
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- 2007
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212. II–VI quantum dots grown by MOVPE
- Author
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Suemune, I., Yoshida, K., Kumano, H., Tawara, T., Ueta, A., and Tanaka, S.
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QUANTUM dots , *SEMICONDUCTORS - Abstract
II–VI quantum dots (QDs) have been under debate on their ripening properties for some time, and a unified understanding of this phenomenon will be given in this paper. Improvement of QD size uniformity is the main concern for practical applications. Scaling of the dot size distributions on some II–VI QDs will be discussed for the better understanding of the size distributions and for the improvement of the dot size uniformity. QD size distributions also tend to smear out the special features of QDs which are expected to modulate electron–photon interactions in optical microcavities coupled with QDs. Study of energy relaxation processes in QDs reveals the possibility of selectively exciting QDs which are in resonance with longitudinal optical (LO)-phonon emission processes. This scheme will be applied to the study of the strong coupling regime of optical microcavities coupled with QDs. CdS/ZnS QDs embedded in pyramidal three-dimensional microcavities are also examined to study the capability to observe enhanced spontaneous emissions by the coupling with cavity modes in pyramidal microcavities. [Copyright &y& Elsevier]
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- 2003
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213. Time-resolved measurements of Cooper-pair radiative recombination in InAs quantum dots.
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Mou, S. S., Irie, H., Asano, Y., Akahane, K., Nakajima, H., Kumano, H., Sasaki, M., Murayama, A., and Suemune, I.
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QUANTUM dots , *LUMINESCENCE , *SEMICONDUCTORS , *QUANTUM electronics , *QUANTUM interference - Abstract
We studied InAs quantum dots (QDs) where electron Cooper pairs penetrate from an adjacent niobium (Nb) superconductor with the proximity effect. With time-resolved luminescence measurements at the wavelength around 1550 nm, we observed luminescence enhancement and reduction of luminescence decay time constants at temperature below the superconducting critical temperature (TC) of Nb. On the basis of these measurements, we propose a method to determine the contribution of Cooper-pair recombination in InAs QDs. We show that the luminescence enhancement measured below TC is well explained with our theory including Cooper-pair recombination. [ABSTRACT FROM AUTHOR]
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- 2015
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214. Room temperature ultraviolet lasing action in high-quality ZnO thin films
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Zhang, X.Q., Suemune, Ikuo, Kumano, H., Yao, Z.G., and Huang, S.H.
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THIN films , *SOLID state electronics , *CRYSTAL growth , *SOLIDS - Abstract
Abstract: High-quality ZnO thin films were grown by plasma-enhanced molecular-beam epitaxy on sapphire substrates. In the edge emission geometry, lasing action has been demonstrated in ZnO thin films. The physical origin responsible for lasing action is discussed. The well-defined longitudinal modes could be observed, the mode spacing of 0.9nm corresponds to a cavity of around 17.5μm, and result from accidentally or naturally formed cavities. The lasing threshold was measured as a function of temperature, and the threshold was found to show weak temperature dependence. [Copyright &y& Elsevier]
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- 2007
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215. Intrinsic exciton transitions in high-quality ZnO thin films grown by plasma-enhanced molecular-beam epitaxy on sapphire substrates.
- Author
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Zhang, X. Q., Yao, Z. G., Huang, S. H., Suemune, Ikuo, and Kumano, H.
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THIN films , *ZINC oxide , *SAPPHIRES , *MOLECULAR beam epitaxy , *PHOTOLUMINESCENCE , *BINDING energy - Abstract
High-quality ZnO thin films have been grown by plasma-enhanced molecular-beam epitaxy on sapphire substrates. Free-exciton absorption and exciton-LO phonon absorption peaks are observed in the films at room temperature, indicating that the exciton states are stable even at room temperature. Three excitonic transitions associated with valence bands A, B, and C are clearly revealed in the reflectance spectrum measured at low temperatures. This result indicates that the ZnO thin films have a perfect wurtzite crystal structure. Biexciton emission is observed in the photoluminescence spectra at low temperatures, from which the biexciton binding energy is estimated to be 14.5 meV, in good agreement with previous results. Exciton-LO (Ex-LO) and exciton-2LO (Ex-2LO) photon emission peaks are observed at low temperature. The energy difference between the Ex-LO and Ex-2LO bands is about 72.5 meV, which coincides with previously reported values of the LO phonon energy for ZnO thin films. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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216. Enhanced Photon Generation in a Nb/n -- InGaAs/p -- InP Superconductor/Semiconductor-Diode Light Emitting Device.
- Author
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Sasakura, H., Kuramitsu, S., Hayashi, Y., Tanaka, K., Akazaki, T., Hanamura, E., Inoue, R., Takayanagi, H., Asano, Y., Hermannstädter, C., Kumano, H., and Suemune, I.
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SEMICONDUCTORS , *ELECTRONICS , *EXCITON theory , *SUPERCONDUCTORS , *OPTOELECTRONICS - Abstract
We experimentally demonstrate Cooper pairs' drastic enhancement of the band-to-band radiative recombination rate in a semiconductor. Electron Cooper pairs injected from a superconducting electrode into an active layer by the proximity effect recombine with holes injected from a p-type electrode. The recombination of a Cooper pair with p-type carriers dramatically increases the photon generation probability of a light-emitting diode in the optical-fiber communication band. The measured radiative decay time rapidly decreases with decreasing temperature below the superconducting transition temperature of the niobium electrodes. Our results indicate the possibility to open up new interdisciplinary fields between superconductivity and optoelectronics. [ABSTRACT FROM AUTHOR]
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- 2011
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217. First-order photon interference of a single photon from a single quantum dot
- Author
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Ekuni, S., Nakajima, H., Sasakura, H., Suemune, I., and Kumano, H.
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OPTICAL interference , *QUANTUM dots , *PHOTON emission , *SUPERPOSITION principle (Physics) , *ORTHOGONALIZATION - Abstract
Abstract: Photon interference indicating wave-like nature of a single photon emitted from a single quantum dot is demonstrated. Photon state as a superposition of two orthogonal linear polarization modes is prepared inside a solid-state single photon source, which causes the first-order interference analogous to the Young’s double slit experiment. The lack of which-mode information is essential for observing the single photon interference. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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218. Relationship between age at onset and magnetic resonance image-defined hyperintensities in mood disorders
- Author
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Takahashi, K., Oshima, A., Ida, I., Kumano, H., Yuuki, N., Fukuda, M., Amanuma, M., Endo, K., and Mikuni, M.
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AFFECTIVE disorders , *AGE , *NEUROCHEMISTRY , *MEDICAL imaging systems - Abstract
Abstract: Objectives: To examine in patients with mood disorders the relationship of age at onset with the location and degree of MRI-defined brain hyperintensities. Method: Fifty-two patients diagnosed as having mood disorders and 14 controls participated in the study. Brain MR images were analyzed according to semiquantitative ratings for the anatomical distribution and severity of T2-weighted hyperintensities. We compared these hyperintensities among the three age- and sex-matched groups of late-onset mood disorder patients (LOM), early-onset mood disorder patients (EOM), and controls. The time since the onset of disorder was significantly longer in the EOM than in the LOM group. We also conducted linear multiple regression analysis using the severity of hyperintensities as dependent variable to determine whether the clinical features correlate with vascular pathology. Results: As for deep white matter hyperintensity (DWMH), LOM exhibited higher ratings than EOM; as for brain areas, significant between-group differences were detected in the bilateral frontal areas and in the left parieto-occipital area. No significant difference was observed between EOM and controls. As for periventricular hyperintensity, there was no difference among the three groups. We obtained a significant regression model to predict DWMH ratings; age, number of ECTs, and LOM were selected as significant variables. Conclusion: The present study suggests that the time since the onset of disorder does not affect the development of white matter lesions, but that white matter lesions are associated with late-onset mood disorders. The frontal areas and the left parieto-occipital area would be important for the development of late-onset mood disorders. [Copyright &y& Elsevier]
- Published
- 2008
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219. Role of Cooper pairs for the generation of entangled photon pairs from single quantum dots
- Author
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Suemune, I., Akazaki, T., Tanaka, K., Jo, M., Uesugi, K., Endo, M., Kumano, H., and Hanamura, E.
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SEMICONDUCTORS , *QUANTUM dots , *QUANTUM electronics , *ELECTRIC conductivity - Abstract
Abstract: Generation of entangled photon pairs from semiconductor quantum dots (QDs) is highly desirable for realizing practical solid-state photon sources for quantum information processing and quantum cryptography. However, the energy splitting of exciton states in QDs almost prevent the generation of entangled photon pairs. This paper discusses the new possibility with the injection of electron as well as hole Cooper pairs into QDs. [Copyright &y& Elsevier]
- Published
- 2008
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220. Detailed Measurements of Nuclear Spin Polarizations in a Single InAlAs Quantum Dot Through Overhauser Shift of Photoluminescence.
- Author
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Kaji, R., Adachi, S., Sasakura, H., Muto, S., Kumano, H., and Suemune, I.
- Abstract
We investigated optical pumping of nuclear spin polarizations in a single self-assembled In0.75Al0.25As/Al0.3Ga0.7As quantum dot. The nuclear spin polarization exhibits the abrupt jump and hysteresis in the excitation power dependence at a particular excitation polarization. Measurement of circular polarization rate of the photoluminescence reveals that the abrupt change of the nuclear spin polarization is created mainly by the spin flip-flop process between nuclei and an electron of a positive charged exciton in this single quantum dot. Model calculation explains well the experimentally observed bistable behavior in InAlAs quantum dot. By using this abrupt change, the sign and magnitude of electron and hole g-factors in z-direction are verified. [ABSTRACT FROM AUTHOR]
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- 2007
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221. Reliability of recalled self-report on headache intensity: investigation using ecological momentary assessment technique.
- Author
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Kikuchi, H., Yoshiuchi, K., Miyasaka, N., Ohashi, K., Yamamoto, Y., Kumano, H., Kuboki, T., and Akabayashi, A.
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HEADACHE , *PAIN perception , *TENSION headache , *MEMORY , *HEALTH risk assessment , *EVERYDAY life , *PATIENTS - Abstract
Recalled evaluation of headache intensity is often affected by several factors. Recently, computerized ecological momentary assessment (EMA) has been developed to avoid such problems as recall bias. Here, we compared recalled headache intensity with momentary headache intensity using EMA in tension-type headache (TTH). Forty patients with TTH wore watch-type computers for 1 week to record momentary headache intensity and also rated their headache intensities by recall. We calculated intraclass correlation coefficients between recalled headache intensity and indices from EMA recordings in the whole study population and in two subgroups divided by variability of momentary headache intensity. The results showed that consistency and agreement of momentary and recalled headache intensity were low, and this was especially marked in the subjects whose headache varied widely. These observations suggested that variability of headache intensity may affect recall of headache intensity and this should be taken into consideration in both clinical and research settings. [ABSTRACT FROM AUTHOR]
- Published
- 2006
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222. HPA axis normalization, estimated by DEX/CRH test, but less alteration on cerebral glucose metabolism in depressed patients receiving ECT after medication treatment failures.
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Yuuki, N., Ida, I., Oshima, A., Kumano, H., Takahashi, K., Fukuda, M., Oriuchi, N., Endo, K., Matsuda, H., and Mikuni, M.
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ELECTROCONVULSIVE therapy , *CORTICOTROPIN releasing hormone , *HYPOTHALAMIC-pituitary-adrenal axis , *POSITRON emission tomography , *DEPRESSED persons , *MENTAL health , *PSYCHIATRY - Abstract
Objective: To examine the clinical effects of electroconvulsive therapy (ECT) on depressed patients with medication treatment failures, we investigated the alterations in hypothalamic-pituitary-adrenocortical (HPA) function and regional cerebral metabolism rate of glucose (rCMRGlu) after ECT in these patients. Method: Before and after ECT, the combined dexamethasone/corticotrophin-releasing hormone (DEX/CRH) test was administered to seven patients who were referred for ECT. In the same patients, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET) was also assessed. Results: Cortisol response in the DEX/CRH test significantly decreased after a successful ECT. A significant hypometabolism in various frontal regions and hypermetabolism in the parietal regions of these patients when compared with controls remained after ECT. Conclusion: Depressed patients who failed trials of antidepressant medication showed a remission with ECT that was accompanied by resolution of HPA dysregulation. However, measures of cerebral brain metabolism did not resolve. [ABSTRACT FROM AUTHOR]
- Published
- 2005
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223. Structural properties of CdO layers grown on GaAs (0 0 1) substrates by metalorganic molecular beam epitaxy
- Author
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Kim, Bong-Joong, Ok, Y.-W., Seong, T.-Y., Ashrafi, A.B.M.A., Kumano, H., and Suemune, I.
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TRANSMISSION electron microscopy , *MICROSTRUCTURE - Abstract
Transmission electron microscopy (TEM) and transmission electron diffraction (TED) examination has been made to investigate the microstructural behaviour of rock-salt CdO layers grown on (0 0 1) GaAs substrates with two different buffer layers of ZnS and ZnO/ZnS. It is shown that the CdO layer grown on the ZnS buffer layer has epitaxial relationship to the GaAs substrate, even though a low density of CdO nano-crystallites (18–25 nm across) are formed at the CdO/ZnS interface region. TEM and TED results show that the CdO layer grown on the ZnO/ZnS buffer layer is polycrystalline. TED results also show that the ZnO buffer layer is polycrystalline with a mixture of wurtzite and zinc-blende phases, which results in the formation of polycrystalline CdO layers. [Copyright &y& Elsevier]
- Published
- 2003
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224. Erbium-doped GaP grown by MOMBE and their optical properties
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Suemune, I., Uesugi, K., Shimozawa, T., Kumano, H., Machida, H., and Shimoyama, N.
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CRYSTAL growth , *CRYSTALLIZATION , *EPITAXY , *LUMINESCENCE - Abstract
Er doping in GaP was studied with metalorganic molecular-beam epitaxy employing a Knudsen cell for Er doping. Coherent growth of the Er-doped GaP layer was observed with relatively smooth surfaces up to Er concentration as high as ∼0.5%. Sharp 1.54-μm luminescence from Er3+ 4f–4f intra-shell transitions showed a weak temperature dependence and was observed up to room temperature. [Copyright &y& Elsevier]
- Published
- 2002
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225. Behavior of pipe flange connection in transient temperature field
- Author
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Kumano, H [Tokyo Metropolitan Inst. of Tech. (Japan)]
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- 1993
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226. Whole-body metabolic map with positron emission tomography of a man after running.
- Author
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Fujimoto, T, Itoh, M, Kumano, H, Tashiro, M, and Ido, T
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- 1996
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227. Optical observation of superconducting density of states in luminescence spectra of InAs quantum dots.
- Author
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Mou, S. S., Irie, H., Asano, Y., Akahane, K., Nakajima, H., Kumano, H., Sasaki, M., Murayama, A., and Suemune, I.
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OPTICAL properties , *SCIENTIFIC observation , *SUPERCONDUCTORS , *INDIUM gallium arsenide , *QUANTUM dots , *LUMINESCENCE , *CRITICAL temperature , *SUPERCONDUCTING transition temperature - Abstract
We study luminescence spectra observed from InAs quantum dots (QDs) embedded in an n-type InGaAs-based heterostructure, where electron Cooper pairs penetrate from an adjacent niobium (Nb) superconductor with the proximity effect. Below the superconducting (SC) critical temperature of Nb, we observe substantial luminescence intensity enhancement and a sharp edge in luminescence spectra of InAs QDs. We explain the observed sharp edge in the luminescence spectra with the proximity effect, that is, with the consideration of opening of SC gap and modification of density of states (DOS) near the electron Fermi level in the n-type semiconductor heterostructure. We demonstrate that the sharp edge luminescence spectra are well reproduced by the SC DOS, with quasiparticle lifetime broadening and a Gaussian distribution of lowest QD state emission lines. We discuss the reason why it has been difficult to observe the sharp edge luminescence spectra in the previous quantum well-based SC light emitting diodes. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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228. Molecular epidemiology and risk analysis for asymptomatic infection with feline enteric coronavirus in domestic and stray cats in Japan.
- Author
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Kumano H and Nakagawa K
- Subjects
- Animals, Cats, Japan epidemiology, Female, Male, Coronavirus Infections veterinary, Coronavirus Infections epidemiology, Coronavirus Infections virology, Prevalence, Risk Assessment, Cat Diseases virology, Cat Diseases epidemiology, Feces virology, Asymptomatic Infections epidemiology, Coronavirus, Feline genetics, Coronavirus, Feline isolation & purification, Coronavirus, Feline classification, Molecular Epidemiology
- Abstract
Feline enteric coronavirus (FECoV) causes subclinical infection; therefore, asymptomatic cats can act as transmitters of FECoV. However, there have been few studies on the prevalence of FECoV in asymptomatic cats in Japan. In this study, we used a nested RT-PCR assay targeting the S gene of FECoV to test 319 normal fecal samples from stray cats and domestic cats in Japan between 2019 and 2020. Seventy-five samples tested positive, and the presence of FECoV in domestic cats was significantly associated with age (p < 0.01), but not with gender, breed, or living in a multi-cat household. The results provide insights into the current prevalence of FECoV in asymptomatic cats in Japan., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Austria, part of Springer Nature.)
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- 2024
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229. Complete genome sequences of feline astroviruses from asymptomatic stray cats in Japan.
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Kitashin I, Kumano H, and Nakagawa K
- Abstract
We determined the complete genome sequences of two feline astroviruses (FAstVs) in non-diarrheic stool samples from apparently healthy stray cats in 2020 in Japan. Information on the complete genome sequence of FAstV from asymptomatic cats has great potential for a better understanding of the ecology of FAstV in cats.
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- 2024
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230. Neural Transformation from Retinotopic to Background-Centric Coordinates in the Macaque Precuneus.
- Author
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Uchimura M, Kumano H, and Kitazawa S
- Abstract
Visual information is initially represented in retinotopic coordinates and later in craniotopic coordinates. Psychophysical evidence suggests that visual information is further represented in more general coordinates related to the external world; however, the neural basis of non-egocentric coordinates remains elusive. This study investigates the automatic transformation from egocentric to non-egocentric coordinates in the macaque precuneus (two males, one female), identified by a functional imaging study as a key area for non-egocentric representation. We found that 6.2% of neurons in the precuneus have receptive fields anchored to the background rather than to the retina or the head, while 16% had traditional retinotopic receptive fields. Notably, these two types were not exclusive: many background-centric neurons initially encode a stimulus's position in retinotopic coordinates (up to ∼90 ms from stimulus onset) but later shift to background coordinates, peaking at ∼150 ms. Regarding retinotopic information, the stimulus dominated the initial period, whereas the background dominated the later period. In the absence of a background, there is a dramatic surge in retinotopic information about the stimulus during the later phase, clearly delineating two distinct periods of retinotopic encoding: one focusing on the figure to be attended and another on the background. These findings suggest that the initial retinotopic information of the stimulus is combined with the background retinotopic information in a subsequent stage, yielding a more stable representation of the stimulus relative to the background through time-division multiplexing. Significance Statement According to psychological literature, the location of visual stimuli is automatically positioned against the background of a scene. This representation relative to the background, not being influenced by eye movements, should be important for stabilizing the visual world. A human functional imaging study suggested that the precuneus in the medial cerebral cortex is a strong candidate. This study recorded neural activity from the precuneus of monkeys and demonstrated the existence of background-centered cells with receptive fields fixed relative to the background., (Copyright © 2024 Uchimura et al.)
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- 2024
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231. Pannus formation: a rare culprit of early bioprosthetic valve dysfunction-a case report.
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Takemoto S, Kumano H, Shimamura J, and Shiose A
- Abstract
Background: Early bioprosthetic valve dysfunction (BVD) due to pannus formation is uncommon in elderly patients, and only a limited number of cases have been reported., Case Summary: An 84-year-old man presented with exertional dyspnoea 3 years after surgical aortic valve replacement (SAVR) with a 19 mm Epic™ valve (Abbott, Santa Clara, CA, USA). Transthoracic echocardiography demonstrated progressive BVD, and cardiac computed tomography (CT) revealed sub-aortic pannus formation. Re-operative SAVR was performed using a 19 mm INSPIRIS RESILIA® valve (Edwards Lifesciences, Irvine, CA, USA), and pathological examination confirmed valve leaflet deformation caused by pannus overgrowth. At the 18-month follow-up, the patient exhibited favourable progress, with no indications of BVD or pannus recurrence., Discussion: This case highlights the importance of recognizing early pannus formation as a cause of BVD, even in elderly patients. Early detection of BVD based on clinical symptoms and echocardiography is vital to allow timely surgical intervention before the deterioration of cardiac function. Cardiac CT helps to differentiate pannus from thrombus formation and guide treatment decisions., Competing Interests: Conflict of interest: None declared., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Cardiology.)
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- 2024
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232. Attention facilitates initiation of perceptual decision making: a combined psychophysical and electroencephalography study.
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Ueno T, Kumano H, and Uka T
- Subjects
- Humans, Male, Female, Young Adult, Adult, Psychophysics, Photic Stimulation methods, Visual Perception physiology, Motion Perception physiology, Electroencephalography methods, Decision Making physiology, Attention physiology, Reaction Time physiology
- Abstract
Humans can selectively process information and make decisions by directing their attention to desired locations in their daily lives. Numerous studies have shown that attention increases the rate of correct responses and shortens reaction time, and it has been hypothesized that this phenomenon is caused by an increase in sensitivity of the sensory signals to which attention is directed. The present study employed psychophysical methods and electroencephalography (EEG) to test the hypothesis that attention accelerates the onset of information accumulation. Participants were asked to discriminate the motion direction of one of two random dot kinematograms presented on the left and right sides of the visual field, one of which was cued by an arrow in 80% of the trials. The drift-diffusion model was applied to the percentage of correct responses and reaction times in the attended and unattended fields of view. Attention primarily increased sensory sensitivity and shortened the time unrelated to decision making. Next, we measured centroparietal positivity (CPP), an EEG measure associated with decision making, and found that CPP latency was shorter in attended trials than in unattended trials. These results suggest that attention not only increases sensory sensitivity but also accelerates the initiation of decision making., (© 2024. The Author(s).)
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- 2024
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233. [Epicardial Pacemaker Infection Treated by Leads Removal via Re-sternotomy:Report of a Case].
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Hashino A and Kumano H
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- Humans, Female, Aged, Device Removal, Prosthesis-Related Infections surgery, Prosthesis-Related Infections therapy, Pacemaker, Artificial adverse effects, Sternotomy
- Abstract
A 69-year-old woman was diagnosed with a pacemaker infection after generator-exchange. Eight years ago, she underwent mitral and tricuspid valve replacement and had biventricular pacing with three pairs of epicardial leads placed in the right atrium, right ventricle, and left ventricle for left ventricular dysfunction. Skin perforation due to infection was detected 1 month after generator-exchange. At first, antibiotic treatment, generator-re-exchange, and pocket repositioning surgery were performed. Following all these failed attempts, a temporary pacemaker was placed, the infected generator was removed, and the lead was cut short. Eight days later, new intravenous caradiac resynchronization therapy pacemaker (CRT-P) implantation was performed. However, despite the repeat debridement, infection at the lead stumps recurred. Moreover, plain chest computed tomography (CT) revealed an abscess around the leads in the anterior mediastinum. Eventually, leads were removed under extracorporeal circulation via re-sternotomy. Postoperative course was uneventful, and she has been doing well without recurrence of infection for 6 years after operation.
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- 2024
234. Tackling social anxiety with targeted brain stimulation: investigating the effects of transcranial static magnetic field stimulation on self-focused attention.
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Tomita N, Katayama H, Kurihara Y, Takahashi T, Shibata S, Mima T, Osu R, and Kumano H
- Abstract
Previous studies suggested that self-focused attention (SFA), implicated in social anxiety disorder (SAD), correlates with heightened activity in the right frontopolar area (rFPA), which is the right prefrontal cortex just behind the forehead. Transcranial static magnetic field stimulation (tSMS) is a non-invasive brain stimulation method capable of temporarily suppressing brain function beneath the magnet. We explored whether tSMS on individuals with tendencies toward SAD elicited (1) suppressing rFPA activation during the resting-state and (2) reducing SFA during a subsequent speech task. Twenty-three university students with social anxiety performed two speech tasks. Between tasks, the tSMS group received neodymium magnet stimulation while the sham group received fake magnet stimulation on the rFPA for 20 min. Resting-state rFPA activities was measured using functional near-infrared spectroscopy (fNIRS), while SFA (body sensations and observer perspective), field perspective, and detached mindfulness (DM) perspective were assessed via questionnaires during both speech tasks. The observer perspective means SFA to self-imagery from others' viewpoint, while the field and DM perspectives mean appropriately focusing on the external environment. The results indicated that tSMS intervention decreased rFPA activity from pre- to post-intervention rest. Then, tSMS reduced SFA to bodily sensations and increased DM perspective from pre- to post-intervention speech, especially in those with high levels of social anxiety. Furthermore, tSMS enhanced the field perspective regardless of social anxiety tendency. The results suggest that tSMS may suppress overactivity in rFPA, reduce SFA to body sensation, and increase adaptive attention in highly socially anxious individuals. Our study suggests the possibility of the clinical application of tSMS for treating SAD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Tomita, Katayama, Kurihara, Takahashi, Shibata, Mima, Osu and Kumano.)
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- 2024
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235. Employment of time-varying sensory evidence to test the mechanisms underlying flexible decision-making.
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Kumano H and Uka T
- Subjects
- Animals, Reaction Time, Brain, Employment, Decision Making, Macaca
- Abstract
To make flexible decisions in dynamic environments, the brain must integrate behaviorally relevant information while simultaneously discarding irrelevant information. This study aimed to investigate the mechanisms responsible for discarding irrelevant information during context-dependent decision-making. We trained two macaque monkeys to switch between direction and depth discrimination tasks in successive trials. During decision-making, the strength of the motion or depth signal changes transiently at various times, introducing a brief pulse. We assessed the effects of pulse on behavioral choices. Consistent with previous findings, early relevant pulses, such as motion pulses during direction discrimination, had a significantly larger effect compared to late pulses. Critically, the effects of irrelevant pulses, such as motion pulses during depth discrimination, exhibited an initial minimal effect, followed by an increase and subsequent decrease as a function of pulse timing. Gating mechanisms alone, aimed at discarding irrelevant information, did not account for the observed time course of pulse effects. Instead, the observed increase in the effects of irrelevant pulses with time suggested the involvement of a leaky integration mechanism. The results suggested that the brain controls the amount of disposal in accumulating sensory evidence during flexible decision-making., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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236. Psychometric properties of the Japanese version of the standardised assessment of personality abbreviated scale.
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Kawashima I, Hinuma T, Nagata M, Yoneyama A, Honjo M, Kumano H, and Tanaka SC
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This study was undertaken to translate the Standardised Assessment of Personality - Abbreviated Scale (SAPAS) into Japanese and to evaluate its validity and reliability. SAPAS is one of the most rapid tools for assessing personality disorder (PD) and has excellent sensitivity and good specificity, whereas other PD assessment tools require such a significant investment of time that they are infeasible for large surveys or routine clinical practice. Customary assessment in clinical practice ideally incorporates screening for PD, as it is associated with a substantial public health burden, including premature mortality and increased health service utilization. Furthermore, PD's status as a key prognostic variable of mental disorders also drives PD screening. While SAPAS has been translated into several languages, there has been no Japanese version. Therefore, we translated SAPAS into Japanese (SAPAS-J) and evaluated its reliability and validity. Study 1 recruited undergraduates to reveal its test-retest reliability. Although its internal consistency was not high, since the intent of the original SAPAS was to assess the broad character of personality disorder with the fewest possible items, minimal correlations between items were reasonable. We tested two factorial models, the single-factor model and the higher-order-single-factor model, and the latter offered better fitting. This higher-order model contained a three-factor structure corresponding to clusters described in DSM-5. It measures general PD traits as a common higher-order latent variable comprising those factors. Correlations of SAPAS-J with the much longer PD screening questionnaire in Study 1 and depressive and anxiety symptoms in Study 2 from the general population support its validity. Although validation for the clinical use of SAPAS-J is limited, our research with non-clinical populations demonstrated sufficient validity to justify its use in the context of psychopathological analog research. Since PD is understood as a continuum, the severity of which is distributed dimensionally, the analog study recruiting from the general population and attempting to reveal psychopathological mechanisms of PD is meaningful., Competing Interests: IK, TH, and ST were employed by Advanced Telecommunications Research Institute International (ATR). MN, AY, and MH were employed by KDDI Research, Inc. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Kawashima, Hinuma, Nagata, Yoneyama, Honjo, Kumano and Tanaka.)
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- 2024
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237. Differences in Psychological Inflexibility Among Men With Erectile Dysfunction Younger and Older Than 40 Years: Web-Based Cross-Sectional Study.
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Saito J, Kumano H, Ghazizadeh M, Shimokawa C, and Tanemura H
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Background: Psychological inflexibility is a core concept of acceptance and commitment therapy (ACT), which is a comprehensive, transdiagnostic interpretation of mental health symptoms. Erectile dysfunction (ED) is a condition that affects male sexual performance, involving the inability to achieve and maintain a penile erection sufficient for satisfactory sexual activity. Psychosocial factors primarily influence ED in men younger than 40 years, whereas biological factors are more likely to be the underlying cause in older men., Objective: This web-based cross-sectional study examined differences in depression, anxiety, and psychological inflexibility among men with ED younger and older than 40 years in a Japanese population., Methods: We used a web-based survey to gather data from various community samples. ED was assessed by the International Index of Erectile Function-5 (IIEF-5) questionnaire, while depression, anxiety, and psychological inflexibility were evaluated by the Patient Health Questionnaire-9 (PHQ-9), General Anxiety Disorder-7 (GAD-7), Acceptance and Action Questionnaire-II (AAQ-II), Cognitive Fusion Questionnaire (CFQ), and Valuing Questionnaire-Obstacle Subscale (VQ-OB) questionnaires. The chi-square test estimated the scores of PHQ-9 and GAD-7 among men with ED, comparing those younger than 40 years and those older than 40 years. Additionally, a two-way ANOVA was conducted with ED severity and age group as independent variables, assessing psychological inflexibility., Results: Valid responses from 643 individuals (mean age 36.19, SD 7.54 years) were obtained. Of these, 422 were younger than 40 years (mean age 31.76, SD 5.00 years), and 221 were older than 40 years (mean age 44.67, SD 2.88 years). There was a statistical difference in the prevalence of depression as judged by PHQ≥10 between men with ED younger and older than 40 years (P<.001). On the other hand, there was no difference in the prevalence of anxiety as judged by GAD≥10 (P=.12). The two-way ANOVA revealed that the interactions for CFQ (P=.04) and VQ-OB (P=.01) were significant. The simple main effect was that men with ED younger than 40 years had significantly higher CFQ (P=.01; d=0.62) and VQ-OB (P<.001; d=0.87) scores compared to those older than 40 years in moderate ED and severe ED. Additionally, it was found that men younger than 40 years with moderate to severe ED had significantly higher CFQ (P=.01; d=0.42) and VQ-OB (P=.02; d=0.38) scores compared to men younger than 40 years without ED. On the other hand, no interaction was found for AAQ-II (P=.16) scores., Conclusions: To the best of our knowledge, this web-based cross-sectional study is the first to examine the relationship between psychological inflexibility and ED. We conclude that men with moderate and severe ED younger than 40 years have higher psychological inflexibility and might be eligible for ACT., (©Junichi Saito, Hiroaki Kumano, Mohammad Ghazizadeh, Chigusa Shimokawa, Hideki Tanemura. Originally published in JMIR Formative Research (https://formative.jmir.org), 03.01.2024.)
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- 2024
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238. Negative pressure wound therapy for prolonged surgical wound healing after brachiobasilic arteriovenous fistula creation in a patient with end-stage liver failure.
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Takai K, Saeki M, Takaoka S, Tada Y, Fujimura R, Harada T, Yamauchi T, and Kumano H
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- Male, Humans, Middle Aged, Veins surgery, Brachial Artery surgery, Treatment Outcome, Vascular Patency, Renal Dialysis, Retrospective Studies, Arteriovenous Shunt, Surgical adverse effects, Surgical Wound, Negative-Pressure Wound Therapy, Liver Failure
- Abstract
A 54-year-old male patient diagnosed with hepatorenal syndrome caused by decompensated alcoholic cirrhosis was referred for arteriovenous fistula (AVF) creation after initiation of hemodialysis. A brachiobasilic arteriovenous fistula (BBAVF) was created because neither forearm had suitable vasculature. Large-volume serous effusion from the incision persisted postoperatively, and we started negative pressure wound therapy (NPWT) for wound protection. The effusion volume decreased gradually; however, up to 80 ml of discharge continued daily. Re-operation was performed 35 days after the initial operation, followed by continued NPWT. The wound was almost healed 85 days after the primary surgery. We present a case of severe surgical wound complication after AVF creation in a patient with hemostatic and coagulation disorders and malnutrition caused by end-stage hepatic failure. We confirmed the usefulness of NPWT for excessive surgical wound effusion and the adequacy of BBAVF for vascular access., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2024
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239. Effect of a Mindfulness-Based Intervention on Self-Compassionate Behaviors: A Randomized Controlled Trial.
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Uchida T, Takahashi T, Sugiyama F, Kikai T, Nitta Y, and Kumano H
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- Humans, Self-Compassion, Empathy, Depression therapy, Anxiety therapy, Mindfulness methods
- Abstract
Self-compassion is regarded as a mediating or moderating variable in mindfulness-based interventions (MBI). However, few studies have investigated the role of self-compassion on MBI. Therefore, we conducted a randomized controlled trial to examine whether (1) MBI decreases depression and trait anxiety, while increasing trait mindfulness, trait self-compassion, self-compassionate behaviors (SC behaviors), mindful behaviors, and mood after behaviors; and (2) SC behaviors moderate the effect of mindful behaviors on mood in daily life. Participants were patients with depression and/or anxiety ( N =19) in Japan. Of the 27 participants recruited, 19 participated in the study. Using stratified randomization, we allocated 10 participants to the intervention group, with an 8-week standard MBI, and nine to the waitlist control group. Depression, trait anxiety, trait mindfulness, and trait self-compassion were assessed using questionnaires, while SC behaviors, mindful behaviors, and mood were measured using an ecological momentary assessment-a method used to repeatedly record events and behaviors in daily life. The results revealed that depression, trait anxiety, trait mindfulness, and trait self-compassion did not significantly change. However, SC behaviors, mindful behaviors, and mood significantly improved with MBI. Moreover, the interaction between SC behaviors and mindful behaviors was significantly shown in the pre-intervention, suggesting that SC behaviors moderate the effect of mindful behaviors on mood in daily life., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2023
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240. An Acceptance and Commitment Therapy Smartphone Application for Erectile Dysfunction: A Feasibility Study.
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Saito J, Kumano H, Ghazizadeh M, Shimokawa C, and Tanemura H
- Abstract
Background: Erectile dysfunction (ED) is a multifactorial disorder with both psychogenic and organic components, but psychosocial factors are usually neglected., Objective: The purpose of this study was to develop a smartphone application targeting psychosocial factors of ED and to examine its feasibility, acceptability, and treatment response to determine the parameters for a larger clinical trial., Methods: In this single-arm feasibility study, 8 participants with situational ED were enrolled. Dr. App, a newly developed smartphone treatment application for patients with psychogenic ED consisting of 8 weekly modules based on Acceptance and Commitment Therapy, was delivered. The primary outcome was comparison of the International Index of Erectile Function-15 domain scores measured pre- and post-intervention., Results: Six out of 8 participants completed the Dr. App and the post-intervention measures. The Wilcoxon signed-rank test showed a significant change in erectile function ( P < 0.05; r = -0.65) and a significant trend in intercourse satisfaction ( P < 0.10; r = -0.47) and overall satisfaction ( P < .10; r = -0.47). Additionally, the reliable change index values were used to calculate the number of participants for whom a clinically meaningful difference occurred. The results showed that 33.30% of the participants had clinically meaningful differences in erectile function and 66.70% in intercourse satisfaction and overall satisfaction. On the other hand, no significant differences were shown in orgasmic function and sexual desire., Conclusions: Findings from this study support the feasibility, acceptability, and potential usefulness of the smartphone application targeting psychosocial factors of ED and warrant a larger randomized clinical trial to confirm the results., Competing Interests: This study was funded by Logos Science Corp Ltd, Tokyo, Japan. M. Ghazizadeh, C. Shimokawa, and H. Tanemura are members of Logos Science Corp, Ltd. The authors have indicated that they have no other conflicts of interest regarding the content of this article., (© 2023 The Authors.)
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- 2023
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241. Development and Validation of a Japanese-Language Questionnaire to Screen for Tension-Type Headaches and Migraines.
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Tanobe K, Machida M, Motoya R, Takeoka A, Danno D, Miyahara J, Takeshima T, Kumano H, and Tayama J
- Abstract
Introduction Migraine and tension-type headache (TTH) are chronic diseases associated with significant socioeconomic losses and social and psychological impact (current global prevalence: 10% and 38%, respectively). Thus, they require accurate identification and classification. In clinical practice, validated screening tools able to quickly determine migraine and TTH with high sensitivity and specificity help provide an objective and multifaceted understanding of patients' headache symptoms. However, no tool has been developed or validated yet in Japan to ask multifaceted questions about headache-related symptoms in order to identify migraine and TTH and understand these symptoms. This study aimed to develop a questionnaire for screening TTH and migraine. Methods The study was conducted from March to June 2022 at a medical institution in Osaka, Japan. The questionnaire - comprising 24 questions that were generated based on the 3rd edition of the International Classification of Headache Disorders - was used to screen for migraine and TTH, aiming for a deeper understanding of related symptoms. The participants were patients aged ≥18 years with at least one of the following diagnoses: migraine, TTH. The participants were asked to respond in writing or online. The inclusion criteria were age ≥18 years; headache patients attending a hospital; and diagnoses of at least one of the following: migraine, TTH. The informativeness and discriminating ability of the screening items were evaluated using the item response theory. Items with a calculated discrimination ≥1.35 (high or very high) were retained for screening purposes. Basic questions required to screen for primary headaches were retained, despite their limited computational discrimination power. Ultimately, nine and eight screening items were finalized for migraine and TTH, respectively. The previous neurologists' clinical diagnosis of each patient was used as the gold standard reference for calculating sensitivity, specificity, and positive and negative predictive values regarding the screening items. Cohen's kappa coefficients with 95% CIs were also calculated to determine the agreement between the neurologists' clinical diagnosis and the questionnaire results. Results The study population comprised 69 patients aged 19-89 years who were assisted at a hospital division specializing in headache medicine and diagnosed by neurologists. Of these, 22 patients had migraine, 30 had TTH, and 17 had migraine/TTH. Comparing the neurologists' clinical diagnosis with our screening questionnaire results, the sensitivity and specificity were 72.7% and 86.7% for migraine and 50.0% and 86.4% for TTH, respectively. Conclusions Our brief screening tool was highly specific for diagnosing migraine and TTH in individuals with headache symptoms but lacked sufficient sensitivity, especially for TTH. The high specificity for migraine and TTH suggests that the screening tool we developed in this study can correctly identify those who do not have migraine and TTH. The sensitivity was also relatively high for migraine, suggesting that the tool can correctly identify migraine-positive individuals. However, the sensitivity for TTH was low. This tool could help clinicians in providing detailed course assessment of migraine symptoms and TTH symptoms; however, the issue of low sensitivity for TTH needs to be addressed., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Tanobe et al.)
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- 2023
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242. Representation of Motion Direction in Visual Area MT Accounts for High Sensitivity to Centripetal Motion, Aligning with Efficient Coding of Retinal Motion Statistics.
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Kumano H and Uka T
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- Male, Animals, Humans, Female, Visual Perception physiology, Neurons physiology, Retina, Macaca mulatta, Photic Stimulation, Motion Perception physiology
- Abstract
The overrepresentation of centrifugal motion in the middle temporal visual area (area MT) has long been thought to provide an efficient coding strategy for optic flow processing. However, this overrepresentation compromises the detection of approaching objects, which is essential for survival. In the present study, we revisited this long-held notion by reanalyzing motion selectivity in area MT of three macaque monkeys (two males, one female) using random-dot stimuli instead of spot stimuli. We found no differences in the number of neurons tuned to centrifugal versus centripetal motion; however, centrifugally tuned neurons showed stronger tuning than centripetally tuned neurons. This was attributed to the heightened suppression of responses in centrifugal neurons to centripetal motion compared with that of centripetal neurons to centrifugal motion. Our modeling implies that this intensified suppression accounts for superior detection performance for weak centripetal motion stimuli. Moreover, through Fisher information analysis, we establish that the population sensitivity to motion direction in peripheral vision corresponds well with retinal motion statistics during forward locomotion. While these results challenge established concepts, considering the interplay of logarithmic Gaussian receptive fields and spot stimuli can shed light on the previously documented overrepresentation of centrifugal motion. Significantly, our findings reconcile a previously found discrepancy between MT activity and human behavior, highlighting the proficiency of peripheral MT neurons in encoding motion direction efficiently. SIGNIFICANCE STATEMENT The efficient coding hypothesis states that sensory neurons are tuned to specific, frequently experienced stimuli. Whereas previous work has found that neurons in the middle temporal (MT) area favor centrifugal motion, which results from forward locomotion, we show here that there is no such bias. Moreover, we found that the response of centrifugal neurons for centripetal motion was more suppressed than that of centripetal neurons for centrifugal motion. Combined with modeling, this provides a solution to a previously known discrepancy between reported centrifugal bias in MT and better detection of centripetal motion by human observers. Additionally, we show that population sensitivity in peripheral MT neurons conforms to an efficient code of retinal motion statistics during forward locomotion., (Copyright © 2023 the authors.)
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- 2023
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243. Summary of the clinical practice manual for late-onset hypogonadism.
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Ide H, Akehi Y, Fukuhara S, Ohira S, Ogawa S, Kataoka T, Kumagai H, Kobayashi K, Komiya A, Shigehara K, Syuto T, Soh J, Tanabe M, Taniguchi H, Chiba K, Matsushita K, Mitsui Y, Yoneyama T, Shirakawa T, Fujii Y, Kumano H, Ueshiba H, Amano T, Sasaki H, Maeda S, Mizokami A, Suzuki K, and Horie S
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- Humans, Testosterone therapeutic use, Obesity, Hormone Replacement Therapy, Hypogonadism diagnosis, Hypogonadism drug therapy, Metabolic Syndrome diagnosis
- Abstract
Testosterone plays an important role in maintaining both physical and mental function. Age-related testosterone depletion contributes to the development of angina, arteriosclerosis, obesity, metabolic syndrome, dementia, frailty, and a range of other conditions. A condition involving age-related testosterone depletion and the associated clinical symptoms is defined as late-onset hypogonadism (LOH). LOH is treated by testosterone replacement therapy. Indications for testosterone replacement therapy are determined by evaluating symptoms and signs., (© 2023 The Japanese Urological Association.)
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- 2023
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244. Triggers of self-focused attention: an ecological momentary assessment study.
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Nanamori M, Tomita N, Kametani C, Matsuda N, and Kumano H
- Abstract
Background: Self-focused attention (SFA) is a major maintenance factor of social anxiety disorder. The two types of SFA, the observer perspective and self-focus on body sensation, increase anxiety in individuals with high levels of social anxiety. However, the triggers of each SFA remain unclear. This study used ecological momentary assessment to identify the factors that elicit SFA in real-life social scenarios., Methods: The study obtained 316 samples from 22 Japanese university students (4 male:18 female) with high social anxiety who completed momentary measures of stimulus perception and two types of SFA for 10 days. Links to online questionnaires were sent to the participants via e-mails 3 times a day. First, multilevel single regression analyses were used to identify the stimuli that induced the two types of SFA. Between-level interaction with gender was done to determine the effect of gender biasing on the female participants. Next, for the variables that were significantly predictive in these analyses, multilevel multiple regression analyses were conducted with fear of each stimulus as a control variable., Results: Perception of gaze, evaluation, and authority predicted SFA from the observer perspective. Perception of gaze also predicted self-focus on body sensation. In addition, the perception of positive response and that of stranger predicted self-focus on body sensation depended on gender, implying that the positive response perception of female participants predicted self-focus on body sensation. After controlling for corresponding fear, gaze perception predicted both SFAs, and the perception of authority predicted SFA from the observer perspective. In addition, after controlling for relevant fear, the perception of positive response of female participants predicted self-focus on body sensation. In contrast, the fear of evaluation but not the perception of evaluation predicted SFA from the observer perspective., Conclusions: The perception of gaze is the most powerful trigger of the two types of SFA, even after controlling for fear of gaze in real-life social scenarios for individuals with social anxiety. SFA from the observer perspective is also triggered by the perception of authority and fear of evaluation. The role of perception of positive responses or strangers should be re-evaluated after correcting for gender imbalance. (350 words / 350 words)., (© 2023. The Author(s).)
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- 2023
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245. Moderating effect of attention deficit hyperactivity disorder tendency on the relationship between delay discounting and procrastination in young adulthood.
- Author
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Oguchi M, Takahashi T, Nitta Y, and Kumano H
- Abstract
Among adults with ADHD, one of the most common problems in daily life is procrastination. ADHD is characterized by attention as well as suboptimal decision-making deficits, indicating difficulty in making long-term reward choices. However, little is known about the relationship between suboptimal decision-making or temporal discounting (TD) and procrastination among adults with ADHD. This study aimed to investigate whether ADHD symptoms enhance the relationship between TD and procrastination. Fifty-eight university participants completed questionnaires about procrastination and an experimental task which measured TD rates in reward and punishment conditions. Only the reward condition showed that ADHD symptoms significantly strengthened the association between the TD rate and procrastination. This study revealed that even when ADHD symptoms were high, higher TD rates were associated with more procrastination, while lower TD rates were associated with less procrastination. The results suggest that procrastination interventions for adult ADHD-prone individuals need to pay attention to reward responses., Competing Interests: The authors declare no competing interests., (© 2023 The Author(s).)
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- 2023
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246. Pavlovian-based neurofeedback enhances meta-awareness of mind-wandering.
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Kawashima I, Nagahama T, Kumano H, Momose K, and Tanaka SC
- Subjects
- Humans, Attention, Electroencephalography, Neurofeedback
- Abstract
Absorption in mind-wandering (MW) may worsen our mood and can cause psychological disorders. Researchers indicate the possibility that meta-awareness of MW prevents these mal-effects and enhances favorable consequences of MW, such as boosting creativity; thus, meta-awareness has attracted psychological and clinical attention. However, few studies have investigated the nature of meta-awareness of MW, because there has been no method to isolate and operate this ability. Therefore, we propose a new approach to manipulate the ability of meta-awareness. We used Pavlovian conditioning, tying to it an occurrence of MW and a neutral tone sound inducing the meta-awareness of MW. To perform paired presentations of the unconditioned stimulus (neutral tone) and the conditioned stimulus (perception accompanying MW), we detected participants' natural occurrence of MW via electroencephalogram and a machine-learning estimation method. The double-blinded randomized controlled trial with 37 participants found that a single 20-min conditioning session significantly increased the meta-awareness of MW as assessed by behavioral and neuroscientific measures. The core protocol of the proposed method is real-time feedback on participants' neural information, and in that sense, we can refer to it as neurofeedback. However, there are some differences from typical neurofeedback protocols, and we discuss them in this paper. Our novel classical conditioning is expected to contribute to future research on the modulation effect of meta-awareness on MW., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2023
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247. Asymmetric Complexity in a Pupil Control Model With Laterally Imbalanced Neural Activity in the Locus Coeruleus: A Potential Biomarker for Attention-Deficit/Hyperactivity Disorder.
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Kumano H, Nobukawa S, Shirama A, Takahashi T, Takeda T, Ohta H, Kikuchi M, Iwanami A, Kato N, and Toda S
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- Adult, Humans, Pupil physiology, Cognition, Biomarkers, Locus Coeruleus physiology, Attention Deficit Disorder with Hyperactivity
- Abstract
Locus coeruleus (LC) overactivity, especially in the right hemisphere, is a recognized pathophysiology of attention-deficit/hyperactivity disorder (ADHD) and may be related to inattention. LC activity synchronizes with the kinetics of the pupil diameter and reflects neural activity related to cognitive functions such as attention and arousal. Recent studies highlight the importance of the complexity of the temporal patterns of pupil diameter. Moreover, asymmetrical pupil diameter, which correlates with the severity of inattention, impulsivity, and hyperactivity in ADHD, might be attributed to a left-right imbalance in LC activity. We recently constructed a computational model of pupil diameter based on the newly discovered contralateral projection from the LC to the Edinger-Westphal nucleus (EWN), which demonstrated mechanisms for the complex temporal patterns of pupil kinetics; however, it remains unclear how LC overactivity and its asymmetry affect pupil diameter. We hypothesized that a neural model of pupil diameter control featuring left-right differences in LC activity and projections onto two opponent sides may clarify the role of pupil behavior in ADHD studies. Therefore, we developed a pupil diameter control model reflecting LC overactivity in the right hemisphere by incorporating a contralateral projection from the LC to EWN and evaluated the complexity of the temporal patterns of pupil diameter generated by the model. Upon comparisons with experimentally measured pupil diameters in adult patients with ADHD, the parameter region of interest of the neural model was estimated, which was a region in the two-dimensional plot of complexity versus left-side LC baseline activity and that of the right. A region resulting in relatively high right-side complexity, which corresponded to the pathophysiological indexes, was identified. We anticipate that the discovery of lateralization of complexity in pupil diameter fluctuations will facilitate the development of biomarkers for accurate diagnosis of ADHD., (© 2022 Massachusetts Institute of Technology.)
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- 2022
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248. Task-specific employment of sensory signals underlies rapid task switching.
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Sasaki R, Kumano H, Mitani A, Suda Y, and Uka T
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- Neurons physiology, Employment, Photic Stimulation, Vision Disparity, Motion Perception physiology
- Abstract
Much of our flexible behavior is dependent on responding efficiently to relevant information while discarding irrelevant information. Little is known, however, about how neural pathways governing sensory-motor associations can rapidly switch to accomplish such flexibility. Here, we addressed this question by electrically microstimulating middle temporal (MT) neurons selective for both motion direction and binocular disparity in monkeys switching between direction and depth discrimination tasks. Surprisingly, we frequently found that the observed psychophysical bias precipitated by delivering microstimulation to neurons whose preferred direction and depth were related to opposite choices in the two tasks was substantially shifted toward a specific movement. Furthermore, these effects correlated with behavioral switching performance. Our findings suggest that the outputs of sensory signals are task specific and that irrelevant sensory-motor pathways are gated depending on task demand so as to accomplish rapid attentional switching., (© The Author(s) 2022. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2022
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249. [Early Structural Valve Deterioration of Bioprosthetic Mitral Valve in a Dialysis Patient].
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Takemoto S, Yamaguchi A, Kumano H, Sugama M, Uezu T, and Mori N
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- Aged, Female, Humans, Mitral Valve surgery, Renal Dialysis, Bioprosthesis, Heart Valve Prosthesis, Mitral Valve Stenosis diagnostic imaging, Mitral Valve Stenosis surgery
- Abstract
Choice of prosthetic valve during valve replacement in dialysis patients is still controversial. There is a known risk of early structural valve deterioration of bioprosthesis in dialysis patients, whereas mechanical prosthesis is associated with a higher risk of bleeding and thrombotic events. A 68-year-old dialysis-dependent woman, who had undergone bioprosthetic mitral valve replacement at the age of 66, was admitted to our hospital because of general malaise and hypotension during dialysis. Echocardiography revealed severe mitral stenosis and regurgitation due to restricted motion and dense calcification in prosthetic valve leaflets, which indicated early structural valve deterioration. Redo mitral valve replacement using a mechanical valve was performed, and the patient gradually recovered. However, she eventually died of intracranial hemorrhage three months after the surgery.
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- 2022
250. Prediction-Related Frontal-Temporal Network for Omission Mismatch Activity in the Macaque Monkey.
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Suda Y, Tada M, Matsuo T, Kawasaki K, Saigusa T, Ishida M, Mitsui T, Kumano H, Kirihara K, Suzuki T, Matsumoto K, Hasegawa I, Kasai K, and Uka T
- Abstract
Sensory prediction is considered an important element of mismatch negativity (MMN) whose reduction is well known in patients with schizophrenia. Omission MMN is a variant of the MMN which is elicited by the absence of a tone previously sequentially presented. Omission MMN can eliminate the effects of sound differences in typical oddball paradigms and affords the opportunity to identify prediction-related signals in the brain. Auditory predictions are thought to reflect bottom-up and top-down processing within hierarchically organized auditory areas. However, the communications between the various subregions of the auditory cortex and the prefrontal cortex that generate and communicate sensory prediction-related signals remain poorly understood. To explore how the frontal and temporal cortices communicate for the generation and propagation of such signals, we investigated the response in the omission paradigm using electrocorticogram (ECoG) electrodes implanted in the temporal, lateral prefrontal, and orbitofrontal cortices of macaque monkeys. We recorded ECoG data from three monkeys during the omission paradigm and examined the functional connectivity between the temporal and frontal cortices by calculating phase-locking values (PLVs). This revealed that theta- (4-8 Hz), alpha- (8-12 Hz), and low-beta- (12-25 Hz) band synchronization increased at tone onset between the higher auditory cortex and the frontal pole where an early omission response was observed in the event-related potential (ERP). These synchronizations were absent when the tone was omitted. Conversely, low-beta-band (12-25 Hz) oscillation then became stronger for tone omission than for tone presentation approximately 200 ms after tone onset. The results suggest that auditory input is propagated to the frontal pole via the higher auditory cortex and that a reciprocal network may be involved in the generation of auditory prediction and prediction error. As impairments of prediction may underlie MMN reduction in patients with schizophrenia, an aberrant hierarchical temporal-frontal network might be related to this pathological condition., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Suda, Tada, Matsuo, Kawasaki, Saigusa, Ishida, Mitsui, Kumano, Kirihara, Suzuki, Matsumoto, Hasegawa, Kasai and Uka.)
- Published
- 2022
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