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2. Charge transfer and weak bonding between molecular oxygen and graphene zigzag edges at low temperatures

Author

Boukhvalov, D. W., Osipov, V. Yu., Shames, A. I., Takai, K., Hayashi, T., and Enoki, T.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics, Condensed Matter - Materials Science, Physics - Chemical Physics, Physics - Computational Physics
Abstract

Electron paramagnetic resonance (EPR) study of air-physisorbed defective carbon nano-onions evidences in favor of microwave assisted formation of weakly-bound paramagnetic complexes comprising negatively-charged O2- ions and edge carbon atoms carrying pi-electronic spins. These complexes being located on the graphene edges are stable at low temperatures but irreversibly dissociate at temperatures above 50-60 K. These EPR findings are justified by density functional theory (DFT) calculations demonstrating transfer of an electron from the zigzag edge of graphene-like material to oxygen molecule physisorbed on the graphene sheet edge. This charge transfer causes changing the spin state of the adsorbed oxygen molecule from S = 1 to S = 1/2 one. DFT calculations show significant changes of adsorption energy of oxygen molecule and robustness of the charge transfer to variations of the graphene-like substrate morphology (flat and corrugated mono- and bi-layered graphene) as well as edges passivation. The presence of H- and COOH- terminated edge carbon sites with such corrugated substrate morphology allows formation of ZE-O2- paramagnetic complexes characterized by small (<50 meV) binding energies and also explains their irreversible dissociation as revealed by EPR., Comment: 28 pages, 8 figures, 2 tables, accepted in Carbon journal

Published
2016

3. Structural analysis of polycrystalline graphene systems by Raman spectroscopy

Author

Ribeiro-Soares, J., Oliveros, M. E., Garin, C., David, M. V., Martins, L. G. P., Almeida, C. A., Martins-Ferreira, E. H., Takai, K., Enoki, T., Magalhães-Paniago, R., Malachias, A., Jorio, A., Archanjo, B. S., Achete, C. A., and Cançado, L. G.

Subjects
Condensed Matter - Mesoscale and Nanoscale Physics
Abstract

A theoretical model supported by experimental results explains the dependence of the Raman scattering signal on the evolution of structural parameters along the amorphization trajectory of polycrystalline graphene systems. Four parameters rule the scattering efficiencies, two structural and two related to the scattering dynamics. With the crystallite sizes previously defined from X-ray diffraction and microscopy experiments, the three other parameters (the average grain boundaries width, the phonon coherence length, and the electron coherence length) are extracted from the Raman data with the geometrical model proposed here. The broadly used intensity ratio between the C-C stretching (G band) and the defect-induced (D band) modes can be used to measure crystallite sizes only for samples with sizes larger than the phonon coherence length, which is found equal to 32 nm. The Raman linewidth of the G band is ideal to characterize the crystallite sizes below the phonon coherence length, down to the average grain boundaries width, which is found to be 2.8 nm. "Ready-to-use" equations to determine the crystallite dimensions based on Raman spectroscopy data are given., Comment: 28 pages, 4 figures

Published
2015
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4. Safety and Effectiveness of Lurasidone in Patients with Schizophrenia: A 12-Week, Open-Label Extension Study

Author

Iyo M, Ishigooka J, Nakamura M, Sakaguchi R, Okamoto K, Mao Y, Tsai J, Fitzgerald A, Takai K, and Higuchi T

Subjects
lurasidone, schizophrenia, antipsychotic, safety, effectiveness, open-label, Neurosciences. Biological psychiatry. Neuropsychiatry, RC321-571, Neurology. Diseases of the nervous system, RC346-429
Abstract

Masaomi Iyo,1 Jun Ishigooka,2 Masatoshi Nakamura,3 Reiko Sakaguchi,4 Keisuke Okamoto,5 Yongcai Mao,6 Joyce Tsai,7 Alison Fitzgerald,8 Kentaro Takai,9 Teruhiko Higuchi10,11 1Department of Psychiatry, Graduate School of Medicine, Chiba University, Chiba, Japan; 2Institute of CNS Pharmacology, Tokyo, Japan; 3Department of Data Science, Drug Development Division, Sumitomo Dainippon Pharma Co., Ltd., Tokyo, Japan; 4Department of Clinical Research, Drug Development Division, Sumitomo Dainippon Pharma Co., Ltd., Tokyo, Japan; 5Department of Clinical Operation, Drug Development Division, Sumitomo Dainippon Pharma Co., Ltd., Tokyo, Japan; 6Division of Data Science, Sunovion Pharmaceuticals Inc., Fort Lee, NJ, USA; 7Division of Clinical Research, Sunovion Pharmaceuticals Inc., Fort Lee, NJ, USA; 8Division of Clinical Operations, Sunovion Pharmaceuticals Inc., Fort Lee, NJ, USA; 9Medical Affairs, Sumitomo Dainippon Pharma Co., Ltd., Tokyo, Japan; 10Japan Depression Center, Tokyo, Japan; 11National Center of Neurology and Psychiatry, Tokyo, JapanCorrespondence: Kentaro Takai Email kentaro-takai@ds-pharma.co.jpPurpose: The goal of this study was to evaluate the safety and effectiveness of lurasidone among patients with schizophrenia in a 12-week open-label extension study.Patients and Methods: Patients who completed a 6-week, double-blind, placebo-controlled study were enrolled in a 12-week open-label extension study with flexible dosing of lurasidone at 40 or 80 mg/day. Safety assessments included adverse events, vital signs, laboratory tests, and electrocardiogram (ECG) parameters. Effectiveness measures included the Positive and Negative Syndrome Scale (PANSS) total score, Clinical Global Impression-Severity Scale (CGI-S), Calgary Depression Scale for Schizophrenia (CDSS) and quality of life measure.Results: A total of 289 patients were enrolled in the open-label extension study. Rates of treatment-emergent adverse events (TEAEs) were low; akathisia was the most common TEAE with an incidence of 6.6%. There were 54 patients (18.7%) who discontinued the extension study, with 17 (5.9%) discontinuing due to adverse events. Minimal or no effects of lurasidone on weight, body mass index, metabolic parameters, prolactin, and ECG parameters were evident. There was continued improvement to week 12 in PANSS and CGI-S scores beyond the initial gains made during the prior 6-week double-blind study. Non-responders to lurasidone 40 mg/day in the prior 6-week study showed a mean (standard deviation) improvement from open-label baseline of 10.7 (13.8) points on the PANSS total score after lurasidone dose was increased to a modal dose of 80 mg/day during the extension study. Changes from double-blind baseline in CDSS and quality of life were maintained in the extension study.Conclusion: Treatment with lurasidone 40 or 80 mg once daily (flexibly dosed) continued to be well tolerated with patients demonstrating further improvement in symptoms over the course of a 12-week open-label extension study in patients with schizophrenia.Keywords: lurasidone, schizophrenia, antipsychotic, safety, effectiveness, open-label

Published
2021

7. Highly Reliable 4 Mb FeRAM Using a Newly Developed PLZT Capacitor With a Bi-Doped SRO Interlayer

Author

Wang, W., Eshita, T., Takai, K., Amari, S., Nakamura, K., Oikawa, M., Sato, N., Ozawa, S., Nakabayashi, M., Mihara, S., Hikosaka, Y., Saito, H., Inoue, K., and Nagai, K.

Abstract

We successfully developed a lanthanum (La)-doped Pb(Zr,Ti)O $_{\boldsymbol {\textbf {3}}}$ (PLZT)-based ferroelectric random access memory (FeRAM) with a newly developed ferroelectric capacitor (FC) employing bismuth (Bi)-doped SrRuO $_{\boldsymbol {\textbf {3}}}$ (B-SRO), aiming to improve the electrical properties and reliability of the FC. Sputter-deposited SrRuO $_{\boldsymbol {\textbf {3}}}$ , commonly used as an interlayer between the metal electrode and ferroelectric layers to improve FC characteristics, does not necessarily result in good electrical properties due to the low atomic density of SRO, typically up to 85%. To address this, we employed a B-SRO interlayer deposited by a B-SRO target with an atomic density up to 95%. FCs utilizing B-SRO exhibit significantly better electrical properties, endurance ( $\gt 10^{\boldsymbol {\textbf {14}}}$ at 90°C), and retention (approximately 10 years at 125°C) compared to FCs without B-SRO. Reliability tests based on JESD22-A108 standards, confirm that our 4Mb FeRAM with B-SRO is highly reliable and commercially available.

Published
2024
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13. Site U1530

Author

de Ronde, C.E.J., primary, Humphris, S.E., additional, Höfig, T.W., additional, Brandl, P.A., additional, Cai, L., additional, Cai, Y., additional, Caratori Tontini, F., additional, Deans, J.R., additional, Farough, A., additional, Jamieson, J.W., additional, Kolandaivelu, K.P., additional, Kutovaya, A., additional, Labonté, J.M., additional, Martin, A.J., additional, Massiot, C., additional, McDermott, J.M., additional, McIntosh, I.M., additional, Nozaki, T., additional, Pellizari, V.H., additional, Reyes, A.G., additional, Roberts, S., additional, Rouxel, O., additional, Schlicht, L.E.M., additional, Seo, J.H., additional, Straub, S.M., additional, Strehlow, K., additional, Takai, K., additional, Tanner, D., additional, Tepley, F.J. III, additional, and Zhang, C., additional

Published
2019
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14. Expedition 376 summary

Author

de Ronde, C.E.J., primary, Humphris, S.E., additional, Höfig, T.W., additional, Brandl, P.A., additional, Cai, L., additional, Cai, Y., additional, Caratori Tontini, F., additional, Deans, J.R., additional, Farough, A., additional, Jamieson, J.W., additional, Kolandaivelu, K.P., additional, Kutovaya, A., additional, Labonté, J.M., additional, Martin, A.J., additional, Massiot, C., additional, McDermott, J.M., additional, McIntosh, I.M., additional, Nozaki, T., additional, Pellizari, V.H., additional, Reyes, A.G., additional, Roberts, S., additional, Rouxel, O., additional, Schlicht, L.E.M., additional, Seo, J.H., additional, Straub, S.M., additional, Strehlow, K., additional, Takai, K., additional, Tanner, D., additional, Tepley, F.J. III, additional, and Zhang, C., additional

Published
2019
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15. Expedition 376 methods

Author

de Ronde, C.E.J., primary, Humphris, S.E., additional, Höfig, T.W., additional, Brandl, P.A., additional, Cai, L., additional, Cai, Y., additional, Caratori Tontini, F., additional, Deans, J.R., additional, Farough, A., additional, Jamieson, J.W., additional, Kolandaivelu, K.P., additional, Kutovaya, A., additional, Labonté, J.M., additional, Martin, A.J., additional, Massiot, C., additional, McDermott, J.M., additional, McIntosh, I.M., additional, Nozaki, T., additional, Pellizari, V.H., additional, Reyes, A.G., additional, Roberts, S., additional, Rouxel, O., additional, Schlicht, L.E.M., additional, Seo, J.H., additional, Straub, S.M., additional, Strehlow, K., additional, Takai, K., additional, Tanner, D., additional, Tepley, F.J. III, additional, and Zhang, C., additional

Published
2019
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20. Site U1491

Author

Fryer, P., primary, Wheat, C.G., additional, Williams, T., additional, Albers, E., additional, Bekins, B., additional, Debret, B.P.R., additional, Deng, J., additional, Dong, Y., additional, Eickenbusch, P., additional, Frery, E.A., additional, Ichiyama, Y., additional, Johnson, K., additional, Johnston, R.M., additional, Kevorkian, R.T., additional, Kurz, W., additional, Magalhaes, V., additional, Mantovanelli, S.S., additional, Menapace, W., additional, Menzies, C.D., additional, Michibayashi, K., additional, Moyer, C.L., additional, Mullane, K.K., additional, Park, J.-W., additional, Price, R.E., additional, Ryan, J.G., additional, Shervais, J.W., additional, Sissmann, O.J., additional, Suzuki, S., additional, Takai, K., additional, Walter, B., additional, and Zhang, R., additional

Published
2018
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21. Expedition 366 summary

Author

Fryer, P., primary, Wheat, C.G., additional, Williams, T., additional, Albers, E.J., additional, Bekins, B., additional, Debret, B.P.R., additional, Deng, J., additional, Dong, Y., additional, Eickenbusch, P., additional, Frery, E.A., additional, Ichiyama, Y., additional, Johnson, K., additional, Johnston, R.M., additional, Kevorkian, R.T., additional, Kurz, W., additional, Magalhaes, V., additional, Mantovanelli, S.S., additional, Menapace, W., additional, Menzies, C.D., additional, Michibayashi, K., additional, Moyer, C.L., additional, Mullane, K.K., additional, Park, J.-W., additional, Price, R.E., additional, Ryan, J.G., additional, Shervais, J.W., additional, Sissmann, O.J., additional, Suzuki, S., additional, Takai, K., additional, Walter, B., additional, and Zhang, R., additional

Published
2018
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22. Site 1200

Author

Fryer, P., primary, Wheat, C.G., additional, Williams, T., additional, Albers, E., additional, Bekins, B., additional, Debret, B.P.R., additional, Deng, J., additional, Dong, Y., additional, Eickenbusch, P., additional, Frery, E.A., additional, Ichiyama, Y., additional, Johnson, K., additional, Johnston, R.M., additional, Kevorkian, R.T., additional, Kurz, W., additional, Magalhaes, V., additional, Mantovanelli, S.S., additional, Menapace, W., additional, Menzies, C.D., additional, Michibayashi, K., additional, Moyer, C.L., additional, Mullane, K.K., additional, Park, J.-W., additional, Price, R.E., additional, Ryan, J.G., additional, Shervais, J.W., additional, Sissmann, O.J., additional, Suzuki, S., additional, Takai, K., additional, Walter, B., additional, and Zhang, R., additional

Published
2018
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23. Expedition 366 methods

Author

Fryer, P., primary, Wheat, C.G., additional, Williams, T., additional, Albers, E., additional, Bekins, B., additional, Debret, B.P.R., additional, Deng, J., additional, Dong, Y., additional, Eickenbusch, P., additional, Frery, E.A., additional, Ichiyama, Y., additional, Johnson, K., additional, Johnston, R.M., additional, Kevorkian, R.T., additional, Kurz, W., additional, Magalhaes, V., additional, Mantovanelli, S.S., additional, Menapace, W., additional, Menzies, C.D., additional, Michibayashi, K., additional, Moyer, C.L., additional, Mullane, K.K., additional, Park, J.-W., additional, Price, R.E., additional, Ryan, J.G., additional, Shervais, J.W., additional, Sissmann, O.J., additional, Suzuki, S., additional, Takai, K., additional, Walter, B., additional, and Zhang, R., additional

Published
2018
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24. Sites U1493, U1494, and U1495

Author

Fryer, P., primary, Wheat, C.G., additional, Williams, T., additional, Albers, E., additional, Bekins, B., additional, Debret, B.P.R., additional, Deng, J., additional, Dong, Y., additional, Eickenbusch, P., additional, Frery, E.A., additional, Ichiyama, Y., additional, Johnson, K., additional, Johnston, R.M., additional, Kevorkian, R.T., additional, Kurz, W., additional, Magalhaes, V., additional, Mantovanelli, S.S., additional, Menapace, W., additional, Menzies, C.D., additional, Michibayashi, K., additional, Moyer, C.L., additional, Mullane, K.K., additional, Park, J.-W., additional, Price, R.E., additional, Ryan, J.G., additional, Shervais, J.W., additional, Sissmann, O.J., additional, Suzuki, S., additional, Takai, K., additional, Walter, B., additional, and Zhang, R., additional

Published
2018
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42. Electron Spin Resonance of NV(–)-Centers in Synthetic Fluorescent Diamond Microcrystals under Conditions of Optical Spin Polarization.

Author

Osipov, V. Yu., Bogdanov, K. V., Rampersaud, A., Takai, K., Ishiguro, Y., and Baranov, A. V.

Subjects
ELECTRON paramagnetic resonance, SPIN polarization, OPTICAL polarization, ARTIFICIAL diamonds, NANODIAMONDS, IRRADIATION, LOW temperatures
Abstract

Electron paramagnetic resonance (EPR) spectra of synthetic diamond microcrystals with NV(‒)‑centers have been studied. It is shown that under the conditions of irradiation of the material with the light of a xenon lamp at low temperatures ~100 K, the intensities of the EPR signals corresponding to the "forbidden" (Δms = 2) and low field allowed (Δms = 1) transitions are amplified several times, while the EPR signals from paramagnetic nitrogen and impurity nickel in the charge state –1 practically do not change. This is due to a change in the population of levels of the ground triplet state of the NV(–)-center and the optical polarization of spins in the state ms = 0 of the triplet level. [ABSTRACT FROM AUTHOR]

Published
2023
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47. Multi-Modal Analysis of Vibration and Meteorological Data for Structures on the World Heritage Site 'Battleship Island'

Author

Kurata, N., Takai, K., Tomioka, A., Daigo, T., Saruwatari, S., and Hamamoto, T.

Abstract

This paper reports the results of vibration and meteorological observations of a buildng built on Hashima, Nagasaki, southern part of Japan, which was registered as a World Heritage Site in 2015 [1], and analyzes its dynamic characteristics. Hashima is called "Battleship Island" because its appearance resembles a battleship due to the many buildings standing upon it. The structure contributing most to the battleship appearance is No. 3 Building. An accelerometer and a weather sensor have been installed in No. 3 Building for long-term measurements. Multi-modal analysis of vibration and meteorological data was performed for 5 months, and the dynamic characteristics of No. 3 Building were examined.

Published
2021
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50. Electron spin resonance of NV-=SUP=-(-)-=/SUP=--centers in synthetic fluorescent diamond microcrystals under conditions of optical spin polarization

Author

null Baranov A.V., null Ishiguro Y., null Takai K., null Rampersaud A., null Bogdanov K. V., and null Osipov V.Yu.

Abstract

Electron paramagnetic resonance (EPR) spectra of synthetic diamond microcrystals with NV(-)-centers have been studied. It is shown that under the conditions of irradiation of the material with the light of a xenon lamp at low temperatures ~ 100 K, the intensities of the EPR signals corresponding to the "forbidden" (Delta ms=2) and low field allowed (Delta ms=1) transitions are amplified several times, while the EPR signals from paramagnetic nitrogen and impurity nickel in the charge state -1 practically do not change. This is due to a change in the population of levels of the ground triplet state of the NV(-)- center and the optical polarization of spins in the state ms=0 of the triplet level. Keywords: nitrogen-vacancy centers, synthetic diamond, electron paramagnetic resonance, spin polarization, luminescence.

Published
2022
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