著者
Maeshima N. Hino K. Yonemitsu K.
出版者
American Physical Society
雑誌
Physical review B (ISSN:10980121)
巻号頁・発行日
vol.82, no.16, pp.161105, 2010-10
被引用文献数
5 5

We study photoinduced ultrafast coherent oscillations originating from orbital degrees of freedom in the one-dimensional two-orbital Hubbard model. By solving the time-dependent Schrödinger equation for the numerically exact many-electron wave function, we obtain time-dependent optical response functions. The calculated spectra show characteristic coherent oscillations that vary with the frequency of probe light. A simple analysis for the dominant oscillating components clarifies that these photoinduced oscillations are caused by the quantum interference between photogenerated states. The oscillation attributed to the Raman-active orbital excitations (orbitons) clearly appears around the charge-transfer peak.
著者
Koshelev A. E. Buzdin A. I. Kakeya I. Yamamoto T. Kadowaki K.
出版者
American Physical Society
雑誌
Physical review B (ISSN:10980121)
巻号頁・発行日
vol.83, no.22, pp.224515, 2011-06
被引用文献数
9

In strongly anisotropic layered superconductors in tilted magnetic fields, the Josephson vortex lattice coexists with the lattice of pancake vortices. Due to the interaction between them, the dissipation of the Josephson vortex lattice is very sensitive to the presence of the pancake vortices. If the c-axis magnetic field is smaller than the corresponding lower critical field, the pancake stacks are not formed but the individual pancakes may exist in the fluctuational regime either near the surface in large-size samples or in the central region for small-size mesas. We calculate the contribution of such fluctuating pancake vortices to the c-axis conductivity of the Josephson vortex lattice and compare the theoretical results with measurements on small mesas fabricated out of Bi2Sr2CaCu2O8+δ crystals. A fingerprint of fluctuating pancakes is a characteristic exponential dependence of the c-axis conductivity observed experimentally. Our results provide strong evidence of the existence of the fluctuating pancakes and their influence on the Josephson vortex lattice dissipation.
著者
Matsubayashi K. Sugai H. Shimono A. Hattori T. Ozaki S. Yoshikawa T. Taniguchi Y. Nagao T. Kajisawa M. Shioya Y. Bland-Hawthorn J.
出版者
IOP Publishing
雑誌
The Astrophysical Journal (ISSN:0004637X)
巻号頁・発行日
vol.761, no.1, 2012-12-10
被引用文献数
3

銀河の「帽子」に吹き付ける強力な風 : M82の銀河風、4万光年先のガス雲と衝突中. 京都大学プレスリリース. 2012-12-27.
著者
浜口 博之 西村 太志 林 信太郎 KAVOTHA K.S. MIFUNDU Wafu NDONTONI Zan 森田 裕一 笠原 稔 田中 和夫 WAFULA Mifundu ZANA Ndontoni WAFULA Mifun ZANA Ndonton KAVOTA K.S.
出版者
東北大学
雑誌
国際学術研究
巻号頁・発行日
1990

この研究は,(1)ホットスポット火山の多いアフリカ大陸の深部構造の解明,並びに(2)ニアムラギラ火山のマグマ活動調査の2項目に大きく分けられる.1990年度の現地調査は予定通り実施され,当初の目的は達成された.1991年度は,現地調査の最中の9月23日にザイ-ルの首都キンシャサを中心に政情不安に端を発した暴動が起こり,日本大使館の退避観告に基づき調査を途中で中断し,隣国に緊急避難しそのまま帰国する結果となった.このため,この年度の調査事項の実施については,不完全なものにならざるを得なかった.以下,2年間の研究実績を項目別に分けて簡潔に示す.1.広帯域地震観測.0.05秒〜370秒に渡って一様な感度を持つCMGー3型とパソコンを用いた地震波収録装置を,1990年度はザイ-ル東部のルイロ地震観測所(LWI)に設置した.1991年度は,キンシャサ効外のビンザ気象局の地下地震計室(BNZ)に設置したが,最後の調整の直前に暴動が起こり,一部未完な状態のまま今日まで観測は続けられている.従って,地震計の再調整を含む良好なデ-タの取得は今後の課題として残された.この観測と並行して実施してきたアフリカ大陸下の深部構造については,(イ)アフリカ直下でコア・マントル境界(CMB)が盛り上がっていること,(ロ)マントル最下部のD"領域ではS波速度が3〜5%遅いこと,逆に,アフリカ大陸の外では数%速いこと,並びに,(ハ)コア表面の温度は,アフリカ大陸を含むA半球がその反対側の太平洋を含むP半球より数10mケルビン高温であること,などが明かとなった.これらの結果はアフリカ大陸に於いてホットスポット火山の密度が高い理由の解釈に重要な手がかりとなる.2.火山性地震・微動観測.1990年度は,CRSN(ザイ-ル自然科学研究所)の定常観測点(4点)の他に,8月13日〜11月29日まで火山地域内で8点の臨時地震観測を実施した.11月20日にこの地域では過去最大のM4の地震がニイラゴンゴ火山南方10kmに起きた.観測結果はこの地震により火山性地震やマグマ活動は励起されず,逆に地溝帯中軸の地震が活発化した事が明らかにされた.また,ニアムラギラの側噴火(キタツングルワ)のストロンポリ式噴火に伴う地震は火口直下0.2〜0.5kmの深さに集中し,その発震機構はマグマの噴出時に働くほぼ鉛直下方のSingle Fo
著者
YAMAMURO K.
雑誌
J. Appl. Phys.
巻号頁・発行日
vol.85, 1999
被引用文献数
14
著者
Nagao M Iso H Yamagishi K Date C Tamakoshi A the JACC Study Group
出版者
Nature Publishing Group
雑誌
European journal of clinical nutrition (ISSN:09543007)
巻号頁・発行日
vol.66, no.6, pp.687-693, 2012-06
被引用文献数
60

BACKGROUND/OBJECTIVES:Although high or low (no) meat consumption was associated with elevated or reduced mortality from cardiovascular disease, respectively, few studies have investigated the association between moderate meat consumption and cardiovascular disease. We aimed to evaluate the associations between moderate meat consumption and cardiovascular disease mortality.SUBJECTS/METHODS:We conducted a prospective cohort study of 51,683 Japanese (20,466 men and 31,217 women) aged 40-79 years living in all of Japan (The Japan Collaborative Cohort Study; JACC Study). Consumptions of meat (beef, pork, poultry, liver and processed meat) were assessed via a food frequency questionnaire administrated at baseline survey. Hazard ratios (HRs) of mortality from cardiovascular disease were estimated from Cox proportional hazards regression models according to quintiles of meat consumption after adjustment for potential confounding variables.RESULTS:During 820,076 person-years of follow-up, we documented 2685 deaths due to total cardiovascular disease including 537 ischemic heart diseases and 1209 strokes. The multivariable HRs (95% confidence interval) for the highest versus lowest quintiles of meat consumption (77.6 versus 10.4 g/day) among men were 0.66 (0.45-0.97) for ischemic heart disease, 1.10 (0.84-1.43) for stroke and 1.00 (0.84-1.20) for total cardiovascular disease. The corresponding HRs (59.9 versus 7.5 g/day) among women were 1.22 (0.81-1.83), 0.91 (0.70-1.19) and 1.07 (0.90-1.28). The associations were similar when the consumptions of red meat, poultry, processed meat and liver were examined separately.CONCLUSION:Moderate meat consumption, up to ~100 g/day, was not associated with increased mortality from ischemic heart disease, stroke or total cardiovascular disease among either gender.
著者
Konabe S. Matsuda K. Okada S.
出版者
American Physical Society
雑誌
Physical review letters (ISSN:00319007)
巻号頁・発行日
vol.109, no.18, pp.187403, 2012-10
被引用文献数
9 4

We theoretically study the phase relaxation of excitons in doped single-walled carbon nanotubes caused by elastic scattering between an exciton and an electron. Our calculation of the spectral linewidth, that is the inverse of the scattering rate, demonstrates that this dephasing process is unexpectedly suppressed in doped single-walled carbon nanotubes, giving rise to anomalous nonlinear behavior as a function of the electron density. A detailed investigation reveals that the logarithmic correction of the exciton self-energy plays a critical role in the exciton-carrier scattering dynamics.
著者
Peng D. L. Sumiyama Kenji Yamamuro S. Hihara Takehiko Konno T. J. ヒハラ タケヒコ スミヤマ ケンジ 隅山 兼治 日原 岳彦 Sumiyama K. Hihara T.
出版者
American Institute of Physics
雑誌
APPLIED PHYSICS LETTERS (ISSN:00036951)
巻号頁・発行日
vol.74, no.1, pp.76-78, 1999-01-04
被引用文献数
33

We have studied electrical conductivity, σ, and magnetoresistance in a CoO-coated monodispersive Co cluster assembly fabricated by a plasma-gas-aggregation-type cluster beam deposition technique. The temperature dependence of σ is described in the form of log σ vs 1/T for 7<T<80 K. The magnetoresistance ratio (ρ0-ρ3T)/ρ0 increases sharply with decreasing temperature below 25 K: from 3.5% at 25 K to 20.5% at 4.2 K. This marked increase (by a factor of 6) is much larger than those observed for conventional metal-insulator granular systems. These results are ascribed to the Coulomb blockade effect in the monodispersed cluster assemblies.
著者
Mengsu Yang Richard Y. C. Kong Najam Kazmi Andrew K. C. Leung
出版者
(社)日本化学会
雑誌
Chemistry Letters (ISSN:03667022)
巻号頁・発行日
vol.27, no.3, pp.257-258, 1998 (Released:2003-02-28)
参考文献数
10
被引用文献数
18

Glass slides and silicon chips were modified with aminosilane and various linker molecules to provide activated surfaces for covalent immobilization of oligonucleotides under ambient condition, and the surface-attached oligonucleotides remain active for solid-phase DNA hybridization and polymerase chain reaction.
著者
Toko K. Kurosawa M. Saitoh N. Yoshizawa N. Usami N. Miyao M. Suemasu T.
出版者
American Institute of Physics
雑誌
Applied physics letters (ISSN:00036951)
巻号頁・発行日
vol.101, no.7, pp.072106, 2012-08
被引用文献数
88 20

(111)-oriented Ge thin films on insulators are essential for advanced electronics and photovoltaic applications. We investigate Al-induced crystallization of amorphous-Ge films (50-nm thickness) on insulators focusing on the annealing temperature and the diffusion controlling process between Ge and Al. The (111)-orientation fraction of the grown Ge layer reaches as high as 99% by combining the low-temperature annealing (325 °C) and the native-oxidized Al (AlOx) diffusion-control layer. Moreover, the transmission electron microscopy reveals the absence of defects on the Ge surface. This (111)-oriented Ge on insulators promises to be the high-quality epitaxial template for various functional materials to achieve next-generation devices.
著者
沢田 勇 Mohammad Mohammad K.
出版者
日本動物分類学会
雑誌
動物分類学会誌 (ISSN:02870223)
巻号頁・発行日
no.39, pp.1-7, 1989-06-25
被引用文献数
2

1985年9月,イラクのハディサで捕獲されたコウモリに膜様条虫に属する2新種が寄生していた.Asellia tridens murraianaに寄生していたVampirolepis mesopotamiana sp.nov.は長さが0.018〜0.022mmで,22〜30本の額嘴鉤を有する既知種8種のいずれとも額嘴鉤の形態が異っている.Rhinopoma microphyllumに寄生していたHymenolepis rhinopomae sp.nov.は台湾産H. scotophiliに極めて類似しているが,頸部の長さ,生殖孔の位置,精巣の配列状態および卵巣の形態が異っている.さらに1985年5月にバグダッドで捕獲されたPipistrellum kuhli ikhwaniusには種の同定が不可能な微小条虫Raillietina(s.l.)sp.が寄生していた.
著者
BULLOUGH K.
雑誌
Nature
巻号頁・発行日
vol.260, pp.401-403, 1976
被引用文献数
1 55