495 results on '"Yohei Kobayashi"'
Search Results
152. P6024The clinical characteristics and outcomes of venous thromboembolism in patients with renal dysfunction: from the COMMAND VTE Registry
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Seiichi Hiramori, Hidewo Amano, Takeshi Morimoto, Yoshiaki Tsuyuki, Toru Takase, Maki Oi, K Kitae, Yohei Kobayashi, H Ishida, N Kanamori, Takeshi Aoyama, Tomohisa Tada, T Kimura, Yugo Yamashita, Command Vte Registry Investigators, and Y Tsutano
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medicine.medical_specialty ,business.industry ,Internal medicine ,medicine ,In patient ,Cardiology and Cardiovascular Medicine ,business ,Venous thromboembolism - Published
- 2018
153. P3563Risk factors for bleeding in patients with venous thromboembolism during long-term anticoagulation therapy: From the COMMAND VTE Registry
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Maki Oi, Tomohisa Tada, Yoshiaki Tsuyuki, Syunsuke Saga, Hidewo Amano, Toru Takase, Kyung-Hwan Kim, Koichiro Murata, Yugo Yamashita, Jirou Sakamoto, Yutaka Furukawa, T Kimura, Yohei Kobayashi, Seiichi Hiramori, and Takeshi Morimoto
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medicine.medical_specialty ,business.industry ,medicine ,In patient ,Cardiology and Cardiovascular Medicine ,Intensive care medicine ,business ,Venous thromboembolism ,Term (time) - Published
- 2018
154. P2609The long-term clinical outcomes of patients with pulmonary embolism and deep vein thrombosis: From the COMMAND VTE Registry
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Tomoya Onodera, Kitae Kim, Yugo Yamashita, Yoshiaki Tsuyuki, Jirou Sakamoto, Command Vte Registry Investigators, Yohei Kobayashi, T Kimura, Hidewo Amano, Toru Takase, Seiichi Hiramori, Takeshi Morimoto, Syunsuke Saga, Maki Oi, Koichiro Murata, and Tomohisa Tada
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medicine.medical_specialty ,medicine.anatomical_structure ,business.industry ,Deep vein ,Medicine ,Cardiology and Cardiovascular Medicine ,business ,medicine.disease ,Thrombosis ,Surgery ,Term (time) ,Pulmonary embolism - Published
- 2018
155. Influence of Baseline Platelet Count on Outcomes in Patients With Venous Thromboembolism (from the COMMAND VTE Registry)
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Yugo Yamashita, Toru Takase, Masaharu Akao, Takeshi Kimura, Kitae Kim, Po-Min Chen, Hirotoshi Watanabe, Syunsuke Saga, Takeshi Morimoto, Takeru Makiyama, Command Vte Registry Investigators, Hiroshi Mabuchi, Yohei Kobayashi, Minako Kinoshita, Yoshiaki Tsuyuki, Kensuke Takabayashi, Hiroki Shiomi, Tomoki Sasa, Jiro Sakamoto, Maki Oi, Koh Ono, Toshiaki Izumi, Koichiro Murata, Seiichi Hiramori, Kiyonori Togi, Tomohisa Tada, Takao Kato, Hidewo Amano, and Mamoru Toyofuku
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Blood Platelets ,Male ,medicine.medical_specialty ,Time Factors ,030204 cardiovascular system & hematology ,Risk Assessment ,03 medical and health sciences ,0302 clinical medicine ,Japan ,Recurrence ,hemic and lymphatic diseases ,Internal medicine ,Cause of Death ,medicine ,Humans ,030212 general & internal medicine ,Registries ,Aged ,Retrospective Studies ,business.industry ,Platelet Count ,Incidence (epidemiology) ,Incidence ,Confounding ,Hazard ratio ,Absolute risk reduction ,Retrospective cohort study ,Venous Thromboembolism ,medicine.disease ,Thrombosis ,Thrombocytopenia ,Confidence interval ,Survival Rate ,Hemostasis ,Cardiology ,Female ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies - Abstract
The influence of thrombocytopenia on the long-term clinical outcomes has not been thoroughly evaluated in patients with venous thromboembolism (VTE). This study sought to elucidate association of baseline thrombocytopenia with bleeding, recurrent VTE, and mortality risk. We evaluated the influence of baseline thrombocytopenia among 3,012 patients whose baseline platelet counts were available in the COMMAND VTE Registry in Japan with a median follow-up period of 1,219 days. Baseline thrombocytopenia was classified as follows: mild: 100,000 to 150,000/μl; moderate: 50,000 to 99,999/μl; and severe
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- 2018
156. Risk factors for post-thrombotic syndrome in patients with deep vein thrombosis: from the COMMAND VTE registry
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Masaharu Akao, Koh Ono, Koichiro Murata, Tomoki Sasa, Seiichi Hiramori, Takao Kato, Yukihito Sato, Po-Min Chen, Kiyonori Togi, Hidewo Amano, Takeshi Kimura, Takeshi Morimoto, Tomohisa Tada, Takeru Makiyama, Toshiaki Izumi, Yohei Kobayashi, Maki Oi, Hiroki Shiomi, Syunsuke Saga, Yugo Yamashita, Mamoru Toyofuku, Yoshiaki Tsuyuki, Hiroshi Mabuchi, Toru Takase, Yuji Nishimoto, Kensuke Takabayashi, Command Vte Registry Investigators, Minako Kinoshita, Jiro Sakamoto, and Kitae Kim
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Male ,medicine.medical_specialty ,Deep vein ,030204 cardiovascular system & hematology ,Thrombophilia ,Risk Assessment ,Postthrombotic Syndrome ,03 medical and health sciences ,0302 clinical medicine ,Japan ,Risk Factors ,Internal medicine ,Medicine ,Humans ,030212 general & internal medicine ,Registries ,Aged ,Retrospective Studies ,Ultrasonography ,Venous Thrombosis ,business.industry ,Incidence ,Phlebography ,Vascular surgery ,medicine.disease ,Prognosis ,Thrombosis ,Discontinuation ,medicine.anatomical_structure ,Female ,Cardiology and Cardiovascular Medicine ,business ,Complication ,Tomography, X-Ray Computed ,Kidney disease ,Post-thrombotic syndrome ,Follow-Up Studies - Abstract
Post-thrombotic syndrome (PTS) is the most common chronic complication of deep vein thrombosis (DVT). Identifying high-risk patients for the development of PTS might be useful for its prevention. The COMMAND VTE Registry is a multicenter registry that enrolled 3027 consecutive patients with acute symptomatic venous thromboembolisms (VTEs) in Japan between January 2010 and August 2014. The current study population consisted of 1298 patients with lower extremities DVTs who completed 3-year follow-up for those who developed PTS and those without PTS. We investigated risk factors for the development of PTS at the time of DVT diagnosis, using a multivariable logistic regression analysis. Of the entire 1298 study patients, 169 (13%) patients were diagnosed with PTS within 3 years. The rate for anticoagulation discontinuation during follow-up was not significantly different between those with and without PTS. Chronic kidney disease (OR 2.21, 95% CI 1.45–3.39, P
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- 2018
157. Anticoagulation Therapy for Venous Thromboembolism in the Real World - From the COMMAND VTE Registry
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Yohei Kobayashi, Tomoyuki Ikeda, Takeru Makiyama, Yoshiaki Tsuyuki, Kazuhisa Kaneda, Katsuhisa Ishii, Syunsuke Saga, Tomoki Sasa, Takeshi Morimoto, Masaharu Akao, Hideo Otani, Koichiro Murata, Mamoru Takahashi, Toshiaki Izumi, Hiroshi Mabuchi, Chinatsu Yamada, Kotaro Takahashi, Takeshi Inoue, Takeshi Kimura, Maki Oi, Koh Ono, Hidewo Amano, Po-Min Chen, Seiichi Hiramori, Kensuke Takabayashi, Kitae Kim, Kiyonori Togi, Minako Kinoshita, Tomohisa Tada, Jiro Sakamoto, Takashi Konishi, Toru Takase, Hiroshi Sakai, Hiroki Shiomi, and Yugo Yamashita
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Male ,medicine.medical_specialty ,Time Factors ,Hemorrhage ,030204 cardiovascular system & hematology ,03 medical and health sciences ,0302 clinical medicine ,Risk Factors ,Internal medicine ,Neoplasms ,medicine ,Humans ,In patient ,Thrombolytic Therapy ,030212 general & internal medicine ,Registries ,Aged ,Aged, 80 and over ,business.industry ,Incidence (epidemiology) ,Incidence ,Cancer ,Anticoagulants ,General Medicine ,Guideline ,Venous Thromboembolism ,Middle Aged ,medicine.disease ,Discontinuation ,Cohort ,Female ,Cardiology and Cardiovascular Medicine ,business ,Venous thromboembolism ,Major bleeding ,Follow-Up Studies - Abstract
BACKGROUND Venous thromboembolism (VTE) has a long-term risk of recurrence, which can be prevented by anticoagulation therapy.Methods and Results:The COMMAND VTE Registry is a multicenter registry enrolling 3,027 consecutive patients with acute symptomatic VTE between January 2010 and August 2014. The entire cohort was divided into the transient risk (n=855, 28%), unprovoked (n=1,477, 49%), and cancer groups (n=695, 23%). The rate of anticoagulation discontinuation was highest in the cancer group (transient risk: 37.3% vs. unprovoked: 21.4% vs. cancer: 43.5% at 1 year, P
- Published
- 2018
158. Rapid Healing of a Spontaneous Coronary Artery Dissection Detected by Computed Tomography Angiography
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Shinichi Shirai, Kenji Ando, Yohei Kobayashi, and Koyu Sakai
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Adult ,Male ,medicine.medical_specialty ,Acute coronary syndrome ,Conservative management ,Computed Tomography Angiography ,Coronary Vessel Anomalies ,Dissection (medical) ,030204 cardiovascular system & hematology ,Conservative Treatment ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,030212 general & internal medicine ,Myocardial infarction ,Vascular Diseases ,Artery dissection ,Computed tomography angiography ,medicine.diagnostic_test ,business.industry ,General Medicine ,medicine.disease ,ST Elevation Myocardial Infarction ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Scad ,Coronary dissection - Abstract
Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome and little is known about characteristics, treatment, and follow-up of patients with SCAD. Computed tomography angiography (CTA) plays an important role in the diagnosis and management of SCAD. Herein, we describe a case of a patient with SCAD who underwent successful conservative management, and in whom CTA was able to detect rapid healing of the dissection, 4.5 hours post-dissection.
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- 2018
159. Pulse-by-pulse depth profile measurement of femtosecond laser ablation on copper
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Shuntaro Tani and Yohei Kobayashi
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Microscope ,Materials science ,Pulse (signal processing) ,business.industry ,medicine.medical_treatment ,02 engineering and technology ,General Chemistry ,021001 nanoscience & nanotechnology ,Laser ,Ablation ,01 natural sciences ,Fluence ,law.invention ,010309 optics ,Optics ,law ,0103 physical sciences ,Femtosecond ,Surface roughness ,medicine ,General Materials Science ,Irradiation ,0210 nano-technology ,business - Abstract
Pulse-by-pulse depth profile measurements were performed during femtosecond laser pulse irradiation on copper. The evolution of the ablation depth and the surface roughness during multi-pulse irradiation was investigated using a three-dimensional microscope. We found that a number of pulse irradiation was required to activate constant-rate ablation and the number of pulses depended on the fluence. We conclude that laser-induced embrittlement of a target material plays a decisive role to determine the ablation rate during multiple-pulse irradiation.
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- 2018
160. Improvement of conversion efficiency of DUV light generation at 221-nm using CLBO crystal
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Hironori Igarashi, Chen Qu, Junichi Fujimoto, Shinji Ito, Taisuke Miura, Mitsuru Tamiya, Yuki Tamaru, Zhigang Zhao, Hakaru Mizoguchi, Yohei Kobayashi, and Hongwen Xuan
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Materials science ,business.industry ,Pulse (signal processing) ,Amplifier ,Energy conversion efficiency ,Frequency mixing ,Laser ,law.invention ,Crystal ,Frequency conversion ,Light source ,law ,Optoelectronics ,business - Abstract
We are developing a 100-W level DUV light source using a solid-state seed laser and an ArF amplifier. Seed pulse at 193nm is generated by the sum frequency mixing of the pulse at 221nm and the pulse at 1553nm using CLBO crystals. To realize a compact and robust seed laser, we improved the conversion efficiency of DUV light generation. In case of the 221nm pulse generation, the conversion efficiency was increased from 22% to nearly 50% by optimizing the conversion process which enables the reduction of amplifier unit of fundamental light source to obtain the 1W seed pulse at 193nm.
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- 2018
161. Efficient high harmonics generation by enhancement cavity driven with a post-compressed FCPA laser at 10 MHz
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Akira Ozawa, Yohei Kobayashi, Makoto Kuwata-Gonokami, and Zhigang Zhao
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Nuclear and High Energy Physics ,Materials science ,business.industry ,Amplifier ,Pulse duration ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Pulse (physics) ,law.invention ,010309 optics ,Finesse ,Nuclear Energy and Engineering ,law ,Harmonics ,0103 physical sciences ,Femtosecond ,Optoelectronics ,Plasma effect ,010306 general physics ,business - Abstract
Efficient high harmonics generation (HHG) was demonstrated at 10 MHz repetition rate with an external femtosecond enhancement cavity, seeded by a ${\sim}70~\text{fs}$ post-compressed 10 MHz fiber chirped pulse amplifier (FCPA) laser. Operation lasting over 30 min with 0.1 mW outcoupled power at 149 nm was demonstrated. It was found that shorter pulse was beneficial for alleviating the nonlinear plasma effect and improving the efficiency of HHG. Low finesse cavity can relax the plasma nonlinearity clamped intra-cavity power and improve the cavity-locking stability. The pulse duration is expected to be below 100 fs for both 1040 nm and 149 nm outputs, making it ideal for applications such as time-resolved photoemission spectroscopy.
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- 2018
162. High power femtosecond FCPA laser and its application in VUV sources generations
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Yohei Kobayashi and Zhigang Zhao
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Materials science ,business.industry ,Amplifier ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,Photon counting ,Pulse (physics) ,law.invention ,010309 optics ,law ,Fiber laser ,0103 physical sciences ,Femtosecond ,Optoelectronics ,Photonics ,0210 nano-technology ,business ,Beam (structure) - Abstract
10.7-eV source with improved beam profile and stability was prepared by employing a specially designed Lens-Window-Prism (LWP) device, driven by a homemade fiber chirped pulse amplifier (FCPA) laser system at 1 MHz.
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- 2018
163. Anomalous Spectral Broadening in High Quality-Factor, 1- GHz Mode-locked Oscillator using Yb:CALGO crystal
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Takuma Nakamura, Shuntaro Tani, Yohei Kobayashi, and Shota Kimura
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Materials science ,Physics::Optics ,Nonlinear optics ,Pulse duration ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,010309 optics ,Optical pumping ,Crystal ,symbols.namesake ,Quality (physics) ,Fourier transform ,Mode-locking ,0103 physical sciences ,symbols ,Atomic physics ,0210 nano-technology ,Doppler broadening - Abstract
An Yb:CALGO Kerr-lens mode-locked oscillator at 1-GHz repetition rate was developed. We found an anomalous spectral broadening at a high pumping-power condition, which lead to a pulse duration of 22 fs.
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- 2018
164. Anterior cruciate ligament injuries in elite and high school rugby players: a 11-year review
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Yoshitomo Saita, Yuji Takazawa, Kazuo Kaneko, Masataka Nagayama, Hiroshi Ikeda, Muneaki Ishijima, Haruka Kaneko, Yohei Kobayashi, Shinnosuke Hada, and Takayuki Kawasaki
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Adult ,Male ,medicine.medical_specialty ,Soft Tissue Injuries ,Anterior cruciate ligament reconstruction ,medicine.medical_treatment ,Anterior cruciate ligament ,education ,Football ,Poison control ,Physical Therapy, Sports Therapy and Rehabilitation ,Knee Injuries ,Transplantation, Autologous ,Cohort Studies ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Injury prevention ,Humans ,Medicine ,Orthopedics and Sports Medicine ,Prospective Studies ,Anterior Cruciate Ligament ,Autografts ,Rupture ,030222 orthopedics ,Schools ,Anterior Cruciate Ligament Reconstruction ,business.industry ,Anterior Cruciate Ligament Injuries ,Incidence ,Incidence (epidemiology) ,030229 sport sciences ,Treatment Outcome ,medicine.anatomical_structure ,Athletic Injuries ,Elite ,Physical therapy ,business ,human activities ,Hamstring ,Follow-Up Studies - Abstract
Over a 11-year period, we investigated the incidence of anterior cruciate ligament (ACL) injuries and the clinical outcomes after ACL reconstruction with hamstring autografts in two homogenous cohorts of rugby players.Two teams, including those in elite (94 players) and high school (290 players) clubs, were followed.Isolated ACL injuries occurred in 28 players (12 elite, 16 high school). The incidence during match play was 1.26 per 1000 player-hours (95% confidence interval [95% CI]: 0.48-2.05) among elite players and 0.97 per 1000 player-hours (95% CI: 0.30-1.64) among high school players. After ACL reconstruction, 26 players (12 elite, 14 high school) were successfully contacted for follow-up at a mean of 71.9 months. None (0%) of the elite and 4 (29%) of the high school players experienced graft ruptures. Seven (58%) elite and 10 (91%) high school players were fearful of reinjury; the mean time to overcome this fear was 6.1 ± 4.9 months among elite players and 17.5 ± 26.0 months among high school players.In conclusion, young rugby players experienced inferior outcomes after ACL reconstruction with hamstring autografts compared with their older counterparts.
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- 2015
165. Current Collapse Reduction in AlGaN/GaN HEMTs by High-Pressure Water Vapor Annealing
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Hirokuni Tokuda, Yohei Kobayashi, Joel T. Asubar, Yukiharu Uraoka, Masaaki Kuzuhara, Koji Yoshitsugu, Zenji Yatabe, Tamotsu Hashizume, and Masahiro Horita
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Suboxide ,Materials science ,Annealing (metallurgy) ,Analytical chemistry ,Wide-bandgap semiconductor ,Oxide ,chemistry.chemical_element ,Gallium nitride ,Oxygen ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,chemistry ,X-ray photoelectron spectroscopy ,Electrical and Electronic Engineering ,Water vapor - Abstract
We have demonstrated for the first time a remarkable reduction of current collapse in AlGaN/GaN high-electron-mobility transistors (HEMTs) by high-pressure water vapor annealing (HPWVA). The device subjected to HPWVA exhibited considerably low dynamic ON-resistance ( $R_{\mathrm{{\scriptscriptstyle ON}}}$ ), suggesting highly improved performance of these devices. Analyses of the results on normalized dynamic $R_{\mathrm{{\scriptscriptstyle ON}}}$ experiments have shown the elimination of deeper traps by HPWVA, leading to the substantially reduced current collapse. X-ray photoelectron spectroscopy (XPS) studies revealed a significant increase in the oxygen core-level O 1s peak. Moreover, angle-resolved XPS suggested the formation of surface oxide layer. These results indicate that the effective reduction of current collapse in the HPWVA-processed samples is likely due to the incorporation of active oxygen species generated by the HPWV into the AlGaN surface. These oxygen atoms eventually fill up near-surface nitrogen vacancies and promote the formation of Ga2O3 native oxide and possibly Ga2O suboxide, which is known to be an excellent III–V surface passivant. HPWVA is a relatively simple, low-damage, and low-temperature process, and hence, it is found to be a highly feasible and promising alternative for realizing AlGaN/GaN HEMTs with improved performance.
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- 2015
166. A novel patient-reported outcome measure for anterior cruciate ligament injury: evaluating the reliability, validity, and responsiveness of Japanese anterior cruciate ligament questionnaire 25
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Masahiko Nozawa, Masashi Nagao, Tokuhide Doi, Mitsuaki Kubota, Haruka Kaneko, Kazuo Kaneko, Muneaki Ishijima, Yohei Kobayashi, Sung-Gon Kim, Hiroshi Ikeda, Yoshitomo Saita, Yuji Takazawa, and Hisashi Kurosawa
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Adult ,Male ,medicine.medical_specialty ,Knee Joint ,Anterior cruciate ligament ,Concurrent validity ,03 medical and health sciences ,0302 clinical medicine ,Physical medicine and rehabilitation ,Cronbach's alpha ,Surveys and Questionnaires ,medicine ,Humans ,Orthopedics and Sports Medicine ,Patient Reported Outcome Measures ,030222 orthopedics ,Anterior Cruciate Ligament Reconstruction ,business.industry ,Item analysis ,Anterior Cruciate Ligament Injuries ,Reproducibility of Results ,030229 sport sciences ,Lysholm Knee Score ,medicine.disease ,ACL injury ,medicine.anatomical_structure ,Orthopedic surgery ,Physical therapy ,Female ,Surgery ,Patient-reported outcome ,business ,Tegner Activity Scale - Abstract
Despite objectively good results, up to 70 % of individuals may not return to their pre-injury level of sports activity after anterior cruciate ligament (ACL) reconstruction surgery. Although psychological responses have been shown to affect outcomes after ACL injury, an appropriate means of measuring their effects, in addition to functional status, has not been determined. The purpose of this study was to develop a patient-reported questionnaire for measuring psychological factors associated with outcomes after ACL injury and to evaluate its reliability, validity, and responsiveness. After item analysis based on the results of two pilot studies and a short relevance assessment, 25 questionnaire items were selected for the Japanese Anterior Cruciate Ligament Injury Questionnaire 25 (JACL-25) and assessed for validity, reliability, and responsiveness in subjects with ACL injury. The JACL-25 had no floor or ceiling effects and no confounding factors. A Cronbach’s alpha coefficient of 0.981 and a Guttman split-half coefficient of 0.983 indicated excellent reliability. Large standardized response means (1.30–1.62) and effect sizes (0.96–1.51) from the preoperative to postoperative period indicated good responsiveness. Construct structures were created, and these items were separated into three domains. Strong correlations between the JACL-25 and the International Knee Documentation Committee Subjective Knee Form (r s = −0.86), Lysholm Score (r s = −0.73), and Tegner Activity Scale (r s = −0.65) indicated good concurrent validity of the JACL-25. The present study demonstrated that the JACL-25 was valid, reliable, and responsive enough to evaluate psychological factors associated with outcomes in individuals with ACL injuries. Diagnostic study, Level III.
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- 2015
167. Stable CW laser based on low thermal expansion ceramic cavity with 4.9 mHz/s frequency drift
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Isao Ito, Takuma Nakamura, Yohei Kobayashi, and Alissa Silva
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Materials science ,business.industry ,Frequency drift ,Physics::Optics ,Cw laser ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Thermal expansion ,law.invention ,010309 optics ,Optics ,law ,Optical frequencies ,Optical materials ,visual_art ,0103 physical sciences ,visual_art.visual_art_medium ,Physics::Accelerator Physics ,Ceramic ,010306 general physics ,business - Abstract
We describe a CW laser stabilized to a low thermal expansion ceramic cavity which has a lower frequency drift rate than cavities based on ultralow-expansion glass (ULE), which are widely used as optical references. Two identical optical cavities with spacers of different material, ceramic and ULE, were assembled and the optical frequencies locked to each of these cavities were compared. The optical frequency drifts of both CW lasers were measured to within a precision of 10−11 in one second over the course of one year. The ceramic cavity had a long-term frequency drift rate of 4.9 mHz/s and the ULE cavity had one of 23 mHz/s.
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- 2017
168. Five-Year Clinical Outcomes After Drug-Eluting Stent Implantation Following Rotational Atherectomy for Heavily Calcified Lesions
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Kenichi Sakakura, Yohei Kobayashi, Shoichi Kuramitsu, Yuhei Yamaji, Tomohiro Shinozaki, Takashi Hiromasa, Kenji Ando, Hiroyuki Jinnouchi, Yoshimitsu Soga, Yukiko Matsumura, Hisaki Masuda, Makoto Hyodo, Shinichi Shirai, Takenori Domei, Yasuaki Takeji, and Mizuki Miura
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Atherectomy, Coronary ,Male ,medicine.medical_specialty ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Revascularization ,Prosthesis Implantation ,03 medical and health sciences ,0302 clinical medicine ,Percutaneous Coronary Intervention ,medicine ,Myocardial Revascularization ,Humans ,Cumulative incidence ,030212 general & internal medicine ,Aged ,Retrospective Studies ,Aged, 80 and over ,business.industry ,Incidence (epidemiology) ,Hazard ratio ,Stent ,Percutaneous coronary intervention ,Calcinosis ,Drug-Eluting Stents ,Thrombosis ,General Medicine ,Middle Aged ,Plaque, Atherosclerotic ,Surgery ,Treatment Outcome ,Drug-eluting stent ,Female ,Hemodialysis ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Follow-Up Studies - Abstract
Background Percutaneous coronary intervention for heavily calcified lesions requires rotational atherectomy (RA). Long-term clinical outcomes after drug-eluting stent (DES) implantation following (RA) for heavily calcified lesions remain unclear. We assessed 5-year clinical outcomes after DES implantation following RA.Methods and Results:Between March 2006 and September 2011, 219 consecutive patients with 219 lesions treated with DES following RA, were retrospectively enrolled. The cumulative 5-year incidence of target-lesion revascularization (TLR) and definite stent thrombosis (ST) were assessed. The cumulative incidence of TLR within (≤) the first year was 18.6%. Late TLR beyond (>) 1 year continued to occur at 1.9% per year without a decrease in the rate (5-year incidence, 26.0%). The cumulative incidence of definite ST at 30 days, 1 and 5 years was 0.9%, 2.3% and 2.9%, respectively. The annual rate of definite ST beyond 1 year was 0.15%. On multivariate analysis, the significant predictor of TLR within 1 year was use of first-generation DES (hazard ratio [HR], 2.09; 95% CI: 1.10-4.03, P=0.02) and that of TLR beyond 1 year was hemodialysis (HR, 3.29; 95% CI: 1.06-10.55, P=0.04). Conclusions Late TLR beyond 1 year continued to occur up to 5 years at a constant annual incidence, whereas very late ST was rare. Careful long-term clinical follow-up is continually needed in patients who have already received DES following RA for heavily calcified lesions.
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- 2017
169. High-speed 100 MHz strain monitor using fiber Bragg grating and optical filter for magnetostriction measurements under ultrahigh magnetic fields
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Hiroshi Watanabe, Yohei Kobayashi, T. Nomura, Keisuke Sato, Akihiko Ikeda, Yasuhiro H. Matsuda, and Shuntaro Tani
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Optical fiber ,Materials science ,FOS: Physical sciences ,Physics::Optics ,02 engineering and technology ,01 natural sciences ,law.invention ,Condensed Matter - Strongly Correlated Electrons ,Optics ,Fiber Bragg grating ,law ,0103 physical sciences ,010306 general physics ,Optical filter ,Instrumentation ,Range (particle radiation) ,Condensed Matter - Materials Science ,Strongly Correlated Electrons (cond-mat.str-el) ,business.industry ,Materials Science (cond-mat.mtrl-sci) ,Magnetostriction ,021001 nanoscience & nanotechnology ,Laser ,Magnetic field ,Magnet ,0210 nano-technology ,business - Abstract
A high-speed 100 MHz strain monitor using a fiber Bragg grating, an optical filter, and a mode-locked optical fiber laser has been devised, which has a resolution of $\Delta L/L\sim10^{-4}$. The strain monitor is sufficiently fast and robust for the magnetostriction measurements of magnetic materials under ultrahigh magnetic fields generated with destructive pulse magnets, where the sweep rate is in the range of 10-100 T/$\mu$s. As a working example, the magnetostriction of LaCoO$_{3}$ was measured at room temperature, 115 K, and 7$\sim$4.2 K up to a maximum magnetic field of 150 T. The smooth $B^{2}$ dependence and the first-order transition were observed at 115 K and 7$\sim$4.2 K, respectively, reflecting the field-induced spin-state evolution., Comment: 5 pages, 2 figures
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- 2017
170. High-power and high-conversion efficiency deep ultraviolet (DUV) laser at 258 nm generation in the CsLiB
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Hongwen, Xuan, Chen, Qu, Shinji, Ito, and Yohei, Kobayashi
- Abstract
We report a 10 kHz, 10.5 W deep ultraviolet (DUV) laser at 258 nm with a pulse duration of 3 ns by fourth-harmonic generation (FHG) in a CsLiB
- Published
- 2017
171. Analysis for Alzheimer's disease using cross-correlation of EEG data
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Takashi Asada, Tohru Yagi, Mieko Tanaka, Kenji Ishii, Yohei Kobayashi, and Yuri Watanabe
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030214 geriatrics ,Cross-correlation ,medicine.diagnostic_test ,business.industry ,0206 medical engineering ,Disease progression ,02 engineering and technology ,Disease ,Electroencephalography ,medicine.disease ,computer.software_genre ,020601 biomedical engineering ,Correlation ,03 medical and health sciences ,0302 clinical medicine ,Eeg data ,medicine ,Dementia ,Phase relation ,Data mining ,business ,computer ,Neuroscience - Abstract
As the elderly population grows, the number of people with dementia is also increasing. If dementia is detected at an early stage, it is possible to slow its progression. Patients with Alzheimer's disease, a type of dementia, show some specific EEG patterns, and we have therefore been investigating EEG analysis to detect Alzheimer's disease. In this paper, we propose a method that evaluates the phase relation between three electrodes. This method enables estimation of the dynamical behavior of an assumed dipole in the deep brain to potentially detect Alzheimer's disease, depending on the disease progression. This method requires only three electrodes and a short period of data collection (1 min). Experimental results show that Alzheimer's disease is identified with over 70% accuracy. Therefore, this Alzheimer's disease detection system appears to be feasible.
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- 2017
172. P4363Coronary flow reserve predicts improvement in left ventricular diastolic function after treatment in patients with impaired glucose tolerance
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M. Tanaka, K. Kajitani, N. Takahashi, H. Yukawa, T. Kanazawa, E. Nakagawa, T. Makita, Yohei Kobayashi, Hideaki Ito, T. Kobayashi, K. Shimamura, Kazuya Nagao, F. Hayashi, N. Tamura, and Tsukasa Inada
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Impaired glucose tolerance ,medicine.medical_specialty ,business.industry ,Internal medicine ,medicine ,Cardiology ,Diastolic function ,In patient ,Cardiology and Cardiovascular Medicine ,medicine.disease ,business ,After treatment - Published
- 2017
173. P4275Incidence and predictors of radial artery stenosis after percutaneous coronary intervention using the transradial approach
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H. Yukawa, S. Kiyotaka, T. Kanazawa, Yohei Kobayashi, K. Kajitani, E. Nakagawa, F. Hayashi, T. Kobayashi, N. Takahashi, M. Tanaka, Kazuya Nagao, A Tamura, T. Makita, Hideaki Ito, and Tsukasa Inada
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Stenosis ,medicine.medical_specialty ,business.industry ,Internal medicine ,medicine.artery ,medicine.medical_treatment ,medicine ,Cardiology ,Percutaneous coronary intervention ,Radial artery ,Cardiology and Cardiovascular Medicine ,medicine.disease ,business - Published
- 2017
174. Pathology of Neointimal Calcification in Very Late Restenosis After Bare Metal Stent Implantation for Superficial Femoral Artery
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Seiichi Hiramori, Katsumi Inoue, Yohei Kobayashi, Kenji Ando, Hiroyuki Jinnouchi, Yoshimitsu Soga, Shinichi Shirai, and Yusuke Tomoi
- Subjects
Bare-metal stent ,Neointima ,Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,030204 cardiovascular system & hematology ,Balloon ,03 medical and health sciences ,0302 clinical medicine ,Restenosis ,Recurrence ,Internal medicine ,Angioplasty ,Medicine ,Humans ,cardiovascular diseases ,030212 general & internal medicine ,medicine.diagnostic_test ,business.industry ,Endovascular Procedures ,Angiography ,Calcinosis ,General Medicine ,Critical limb ischemia ,Intermittent Claudication ,Middle Aged ,equipment and supplies ,medicine.disease ,Femoral Artery ,Cardiology ,Stents ,medicine.symptom ,Cardiology and Cardiovascular Medicine ,business ,Calcification ,Follow-Up Studies - Abstract
A 60-year-old man, who had claudication in his right limb due to total occlusion of the right superficial femoral artery, received bare metal stents. Although the bare metal stents in the superficial femoral artery did not show restenosis 5 years after stent implantation, angiography revealed significant in-stent restenosis when he developed right critical limb ischemia at 8 years post implantation. Ballooning for in-stent lesions did not result in full expansion. His right limb was amputated above the knee due to progressive limb ischemia. In the pathological findings in the superficial femoral artery, marked calcification was observed in the entire circumference of the luminal surface of the neointima. However, lipid core formation was not identified in the neointima. Although several cracks following balloon angioplasty were observed at the superficial calcified layers, injury to neointimal tissue such as compression was not observed. The neointima exhibited heavy calcification in the very late phase of in-stent restenosis after bare metal stent implantation in superficial femoral artery. Therefore, balloon angioplasty in the very late phase of in-stent restenosis potentially results in underexpansion.
- Published
- 2017
175. Extremely-high-order Ge immersion grating-based spectrometer for offset-free precision spectroscopy in the mid-infrared region
- Author
-
Takuma Nakamura, Shuntaro Tani, Takashi Sukegawa, and Yohei Kobayashi
- Subjects
Diffraction ,Materials science ,010304 chemical physics ,Spectrometer ,Phased array ,business.industry ,Detector ,Physics::Optics ,Grating ,Diffraction efficiency ,01 natural sciences ,010309 optics ,Optics ,0103 physical sciences ,Spectroscopy ,business ,Astrophysics::Galaxy Astrophysics ,Echelle grating - Abstract
Precision spectroscopy in the mid-infrared (MIR) region is of great importance for many applications including breath diagnosis and astronomical spectroscopy as various molecular vibrational modes exist in this region. A mid-infrared comb combined with a broadband comb-resolved spectrometer can be a promising method to do this since target gas contains multiple molecular species in most applications. A two-dimensional array detector and highly dispersive diffraction optics such as a virtually-imaged phased array (VIPA) achieved such a spectrometer[1]. Although VIPAs are a powerful tool to fulfill both high resolution and broad bandwidth, the diffraction efficiency cannot be very high in principle. On the other hand, echelle gratings can realize relatively high diffraction efficiency, but the use for broadband comb-resolved spectroscopy has been limited because of their diffraction order of a few hundred[2]. In this study, we constructed a high-throughput spectrometer for a 1-GHz comb by developing an extremely-high-order germanium immersion echelle grating (EGIG).
- Published
- 2017
176. Chronic myocarditis with a long clinical course: Report of an autopsy case of probable autoimmune myocarditis
- Author
-
Masayuki, Shintaku, Koji, Uchiyama, and Yohei, Kobayashi
- Subjects
Myocarditis ,Fatal Outcome ,Chronic Disease ,Humans ,Female ,Autopsy ,Middle Aged ,Autoimmune Diseases - Abstract
The patient was a 54-year-old woman, who died of chronic cardiac insufficiency after a clinical course of 2 years and 4 months. She had complained of myalgia, muscle weakness, and blepharoptosis before the onset of cardiac symptoms, but there was no evidence of myasthenia gravis or collagen-vascular diseases. At autopsy, the heart (280 g) showed marked dilatation of the four chambers and thinning of the ventricular walls. Diffuse and intense lymphocytic infiltration and extensive fibrosis were noted, with the latter being accentuated in the subendocardial and subepicardial zones. Small foci of myocardial necrosis were scattered and a small number of multinucleated giant cells were found, but epithelioid cell granulomas, Aschoff's nodules, and viral inclusion bodies were not observed. Some cardiomyocytes showed the aberrant expression of the HLA-DR antigen. No viral genomes were detected in myocardial tissue using a multivirus real-time polymerase chain reaction. The protracted clinical course, presence of active inflammatory changes at autopsy, expression of the HLA-DR antigen on cardiomyocytes, and absence of viral genomes in myocardial tissue suggest that autoimmune mechanisms played an important role in the pathogenesis and persistence of myocarditis in this patient.
- Published
- 2017
177. Lipopolysaccharide (LPS)-binding protein stimulates CD14-dependent Toll-like receptor 4 internalization and LPS-induced TBK1-IKKϵ-IRF3 axis activation
- Author
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Hisashi Aso, Muneo Numasaki, Kanae Kubota, Misaki Okubo, Kouichi Watanabe, Yoshitomi Kanemitsu, Ippo Ukai, Yotaro Matsumoto, Ayumi Shichiku, Sao Kozakai, Yoshihisa Tomioka, Tomonori Nochi, Shino Takeuchi, Yohei Kobayashi, and Hiroki Tsukamoto
- Subjects
0301 basic medicine ,Lipopolysaccharides ,Endosome ,CD14 ,media_common.quotation_subject ,education ,Immunology ,Lipopolysaccharide Receptors ,Lymphocyte Antigen 96 ,Protein Serine-Threonine Kinases ,Biochemistry ,03 medical and health sciences ,0302 clinical medicine ,Cell surface receptor ,Humans ,Phosphorylation ,Receptor ,Internalization ,Molecular Biology ,media_common ,Toll-like receptor ,Membrane Glycoproteins ,Chemistry ,Cell Biology ,Cell biology ,I-kappa B Kinase ,Toll-Like Receptor 4 ,Protein Transport ,030104 developmental biology ,TRIF ,030220 oncology & carcinogenesis ,TLR4 ,lipids (amino acids, peptides, and proteins) ,Interferon Regulatory Factor-3 ,Carrier Proteins ,Acute-Phase Proteins - Abstract
Toll-like receptor 4 (TLR4) is an indispensable immune receptor for lipopolysaccharide (LPS), a major component of the Gram-negative bacterial cell wall. Following LPS stimulation, TLR4 transmits the signal from the cell surface and becomes internalized in an endosome. However, the spatial regulation of TLR4 signaling is not fully understood. Here, we investigated the mechanisms of LPS-induced TLR4 internalization and clarified the roles of the extracellular LPS-binding molecules, LPS-binding protein (LBP), and glycerophosphatidylinositol-anchored protein (CD14). LPS stimulation of CD14-expressing cells induced TLR4 internalization in the presence of serum, and an inhibitory anti-LBP mAb blocked its internalization. Addition of LBP to serum-free cultures restored LPS-induced TLR4 internalization to comparable levels of serum. The secretory form of the CD14 (sCD14) induced internalization but required a much higher concentration than LBP. An inhibitory anti-sCD14 mAb was ineffective for serum-mediated internalization. LBP lacking the domain for LPS transfer to CD14 and a CD14 mutant with reduced LPS binding both attenuated TLR4 internalization. Accordingly, LBP is an essential serum molecule for TLR4 internalization, and its LPS transfer to membrane-anchored CD14 (mCD14) is a prerequisite. LBP induced the LPS-stimulated phosphorylation of TBK1, IKKϵ, and IRF3, leading to IFN-β expression. However, LPS-stimulated late activation of NF-κB or necroptosis were not affected. Collectively, our results indicate that LBP controls LPS-induced TLR4 internalization, which induces TLR adaptor molecule 1 (TRIF)-dependent activation of the TBK1–IKKϵ–IRF3–IFN-β pathway. In summary, we showed that LBP-mediated LPS transfer to mCD14 is required for serum-dependent TLR4 internalization and activation of the TRIF pathway.
- Published
- 2017
178. New Endovascular Technique to Prevent Distal Embolism for Iliofemoral Occlusive Disease: Reverse Flow Aspiration With Proximal Sheath Blockage
- Author
-
Kenji Aodo, Naotaka Murata, Yoshimitsu Soga, Seiichi Hiramori, Yusuke Tomoi, Kei Ichihashi, and Yohei Kobayashi
- Subjects
Male ,medicine.medical_specialty ,Time Factors ,medicine.medical_treatment ,Distal embolization ,Embolism ,Occlusive disease ,Collateral Circulation ,030204 cardiovascular system & hematology ,Iliac Artery ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Peripheral Arterial Disease ,0302 clinical medicine ,Risk Factors ,Occlusion ,Medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Prospective Studies ,Aged ,Aged, 80 and over ,Iliac artery ,business.industry ,Superficial femoral artery ,medicine.disease ,Surgery ,Femoral Artery ,Treatment Outcome ,Amputation ,Regional Blood Flow ,Balloon dilation ,Female ,Stents ,Radiology ,Cardiology and Cardiovascular Medicine ,business ,Angioplasty, Balloon ,Vascular Access Devices - Abstract
To report the safety and efficacy of a new technique to prevent distal embolism during treatment of iliofemoral occlusions: reverse flow aspiration with proximal sheath blockage (ReFLAP).Between October 2013 and December 2014, 90 patients (mean age 74 years; 66 men) were prospectively enrolled in a study to evaluate the ReFLAP technique during treatment of 110 occlusions in the iliac artery (72, 65%) or superficial femoral artery (SFA; 38, 35%). The mean occlusion lengths of iliac and SFA lesions were 79 and 179 mm, respectively. The concept of ReFLAP is to aspirate debris after balloon dilation using reverse flow through collaterals without antegrade flow. The main endpoints were the incidence of distal embolization, amputation, complications, and the ReFLAP capture rate, which was visually estimated during aspiration using 4 prespecified grades (0, none; 1, foamy debris; 2, small particles; 3, massive particles).ReFLAP was successful in 105 (95.4%) of the 110 lesions attempted; the 5 failures were due to severe vessel tortuosity or calcification. The incidences of distal embolization and amputation were both 0. Minor complications unrelated to ReFLAP were observed in 8 patients. The ReFLAP procedure aspirated debris in 57 (54%) of the 105 lesions. Aspirated material, including marked clots (grades 2 and 3), was confirmed in 40 (38%) of the lesions. The distribution of aspiration grades was significantly different between iliac and SFA lesions (p=0.02).Our results suggest that the ReFLAP endovascular technique to prevent distal embolization during iliofemoral occlusive disease treatment is simple, safe, and effective.
- Published
- 2017
179. Observing laser ablation dynamics with sub-picosecond temporal resolution
- Author
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Shuntaro Tani and Yohei Kobayashi
- Subjects
Electromagnetic field ,Optics ,Laser ablation ,Amplitude ,Materials science ,business.industry ,Picosecond ,Temporal resolution ,Femtosecond ,Optoelectronics ,Time domain ,business ,Charged particle - Abstract
Laser ablation is one of the most fundamental processes in laser processing, and the understanding of its dynamics is of key importance for controlling and manipulating the outcome. In this study, we propose a novel way of observing the dynamics in the time domain using an electro-optic sampling technique. We found that an electromagnetic field was emitted during the laser ablation process and that the amplitude of the emission was closely correlated with the ablated volume. From the temporal profile of the electromagnetic field, we analyzed the motion of charged particles with subpicosecond temporal resolution. The proposed method can provide new access to observing laser ablation dynamics and thus open a new way to optimize the laser processing.
- Published
- 2017
180. 149.8 nm, the shortest wavelength generated by phase matching in nonlinear crystals
- Author
-
Chuangtian Chen, Shuntaro Watanabe, Isao Ito, Yohei Kobayashi, Tomoharu Nakazato, and Xiaoyang Wang
- Subjects
010302 applied physics ,Materials science ,business.industry ,Nonlinear optics ,Nanosecond ,Laser ,01 natural sciences ,law.invention ,010309 optics ,Wavelength ,Optics ,law ,0103 physical sciences ,Transmittance ,Optoelectronics ,Sellmeier equation ,Photolithography ,business ,Absorption (electromagnetic radiation) - Abstract
Narrow band light sources in the vacuum ultraviolet (VUV) region are attractive for photo lithography and high resolution photoelectron spectroscopy. Phase matching is essential to generate high power VUV lights by using a narrow band, low peak intensity and nanosecond pump source. In this research, sum frequency mixing has been demonstrated below 150 nm in KBe2BO3F2 by using the fundamental with its fourth harmonic of a 6 kHz Ti:sapphire laser. The laser system we have developed in this research, consists of a Ti:sapphire laser system and a frequency conversion stage. We generated 149.8-nm radiation, which is the shortest wavelength ever obtained to our knowledge by phase matching in nonlinear crystals. The fifth harmonic output powers were 3.6 μW at 149.8 nm and 110 μW at 154.0 nm, respectively. The phase matching angles measured from 149.8 nm to 158.1 nm are larger by 3-4 degrees than those expected from the existing Sellmeier equation. The optical transmission spectra of some KBBF crystals were measured by the spectrophotometer. The transmittance near the absorption edge supports the generation of coherent radiation below 150 nm. The improvement of a prism-coupled device contributed to the generation of coherent radiation below 150 nm. Another reason for the present break through to the shorter wavelength is the use of the short pulse driving source compared with our previous research.
- Published
- 2017
181. Estimated Prevalence of Heterozygous Familial Hypercholesterolemia in Patients With Acute Coronary Syndrome
- Author
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Hirotoshi, Ohmura, Yoshifumi, Fukushima, Atsushi, Mizuno, Koichiro, Niwa, Yohei, Kobayashi, Toshiaki, Ebina, Kazuo, Kimura, Shun, Ishibashi, and Hiroyuki, Daida
- Subjects
Aged, 80 and over ,Male ,Heterozygote ,Genetic Carrier Screening ,Middle Aged ,Achilles Tendon ,Hyperlipoproteinemia Type II ,Japan ,Surveys and Questionnaires ,Prevalence ,Humans ,Female ,Prospective Studies ,Acute Coronary Syndrome ,Aged - Abstract
Heterozygous familial hypercholesterolemia (FH) represents a strong risk for development of premature coronary artery disease (CAD). However, the majority of patients with FH are undiagnosed and the prevalence likely represents an underestimate in most countries. In Japan, the possible contribution of FH to the development of CAD may be higher because of the low incidence of CAD among the general population. We estimated the prevalence of heterozygous FH by measuring Achilles tendon thickness (ATT) in patients with acute coronary syndrome (ACS).A total of 359 patients suffering from ACS were enrolled in this multicenter registration study. Heterozygous FH was defined according to the diagnostic criteria proposed by the Japan Atherosclerosis Society. After excluding 63 patients because of missing ATT data or plasma triglyceride levels that were 4.5 mmol/L or more, 296 patients were eligible for inclusion in the study. The number of patients with ATT of 9 mm or more was 53 (17.9%). They were significantly younger and had significantly higher LDL cholesterol levels than patients with an ATT less than 9 mm. The prevalence of heterozygous FH was 5.7% (1/17.5) and more prominent in younger patients who were less than 60 years old (7.8%). In patients with ATT of 9 mm or more, approximately 1 in 3.5 fulfilled the criteria for heterozygous FH.We demonstrated the usefulness of measuring ATT by radiography and the high prevalence of heterozygous FH in patients with ACS in Japan, especially in younger patients who were less than 60 years old.
- Published
- 2017
182. A CW laser stabilized to a low expansion ceramic cavity with a 7 mHz/s frequency drift
- Author
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Isao Ito, Takuma Nakamura, Alissa Silva, and Yohei Kobayashi
- Subjects
010302 applied physics ,Materials science ,business.industry ,Frequency drift ,Cw laser ,Laser ,01 natural sciences ,law.invention ,010309 optics ,Resonator ,Optics ,law ,visual_art ,0103 physical sciences ,visual_art.visual_art_medium ,Ceramic ,business - Abstract
We developed a CW laser stabilized to a low expansion ceramic cavity with a frequency drift 7 mHz/s (δf/f ∼ 10−10 /year), which is lower than those achieved with ultra-low expansion glass cavities. OCIS codes: (140.4780) Optical resonators; (140.3425) Laser stabilization; (120.2230) Fabry-Perot
- Published
- 2017
183. A mW-level 10.7-eV (λ=115.6nm) VUV Laser By Cascaded Third Harmonic Generation of A Yb:fiber Laser at 1-MHz
- Author
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Zhigang Zhao and Yohei Kobayashi
- Subjects
010302 applied physics ,Distributed feedback laser ,Materials science ,High power lasers ,business.industry ,Energy conversion efficiency ,Laser ,01 natural sciences ,law.invention ,010309 optics ,law ,Fiber laser ,0103 physical sciences ,Optoelectronics ,Fiber ,Third harmonic ,business ,Laser beams - Abstract
A mW-level 10.7-eV VUV laser was demonstrated, based on cascaded third harmonic generation of a 1-MHz Yb:fiber CPA laser. The conversion efficiency from 347 nm to 115.6 nm (10.7 eV) was ~2.5×10-4.
- Published
- 2017
184. Neuronal Activity Topography Parameters as a Marker for Differentiating Vascular Cognitive Impairment in Carotid Stenosis
- Author
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Karin Hayashi, Mieko Tanaka, Takashi Asahi, Yohei Kobayashi, Takashi Asada, Yukio Horie, Naoya Kuwayama, Takashi Shibata, Michiya Kubo, Toshimitu Musha, Haruyasu Matsuzaki, and Satoshi Kuroda
- Subjects
Male ,Pathology ,medicine.medical_specialty ,Neuroimaging ,Neuropsychological Tests ,Electroencephalography ,Diagnosis, Differential ,Predictive Value of Tests ,Humans ,Medicine ,Premovement neuronal activity ,Carotid Stenosis ,False Positive Reactions ,Cognitive impairment ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,Resting state fMRI ,business.industry ,Dementia, Vascular ,Rehabilitation ,Cognition ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Stenosis ,Closed eyes ,Female ,Surgery ,Neurology (clinical) ,Alzheimer's disease ,Cognition Disorders ,Cardiology and Cardiovascular Medicine ,business - Abstract
Previously, we reported on the differentiation between patients with Alzheimer disease and normal controls using a quantitative electroencephalographic technique called neuronal activity topography (NAT). In this technique, cerebral neuronal activities are characterized by the signal intensity and coherence (sNAT and vNAT, respectively). In the present study, we examined 47 patients with vascular cognitive impairment in carotid stenosis and 52 normal controls. All subjects underwent electroencephalography in a resting state with closed eyes for 5 minutes. Electroencephalographic markers of the differential likelihood, that is, the sensitivity-versus-specificity characteristics, sL(x:VCI-NLc) and vL(x:VCI-NLc), were assessed with neuronal activity topography and were compared between the 2 groups. sL(x:VCI-NLc) and vL(x:VCI-NLc) crossed each other at a cutoff value of the differential likelihood. Separation of the patients and controls was made with a sensitivity of 92% and 88%, as well as a false-positive rate of 8% and 12% for sL(x:VCI-NLc) and vL(x:VCI-NLc), respectively. Using sNAT, we accurately differentiated 92% patients with vascular cognitive impairment. We recommend that sNAT, rather than vNAT, should be used in detecting vascular cognitive impaired patients.
- Published
- 2014
185. Non-invasive Serum Cholesterol Detection Using Near-infrared Light Transmission
- Author
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Masataka Nakabayashi, Naotaka Sakai, Satoshi Shimawaki, and Yohei Kobayashi
- Subjects
medicine.medical_specialty ,Near infrared light ,Anemia ,Cholesterol ,Non invasive ,Pharmaceutical Science ,Spleen ,Biology ,medicine.disease ,Surgery ,chemistry.chemical_compound ,Endocrinology ,medicine.anatomical_structure ,Complementary and alternative medicine ,chemistry ,Internal medicine ,Cuff ,medicine ,Pharmacology (medical) ,Hemoglobin ,Serum cholesterol - Abstract
This paper investigated whether a simple, non-invasive blood vessel visualization technique using near-infrared light is suitable for determining serum cholesterol levels. Six-week-old male Wistar rats were divided into 6 groups (n = 10/group) and were fed either control diet alone or control diet with 0.5%, 1.0%, 1.25%, 1.5%, or 2.0% cholesterol for 8 weeks. A cuff was subsequently placed on the proximal part of the tail (cuff pressure, 80 mmHg), the tail distal to the compression site was exposed to near-infrared light (wavelength, 850 nm), and transmitted light was photographed. Near-infrared transmission images were acquired before and after cuff inflation, and hemoglobin and haematocrit levels in veins distal to the compression site were determined. Increased dietary cholesterol levels resulted in increased total serum cholesterol levels. Before cuff inflation, rats that were fed the 2.0% cholesterol diet had significantly lower hemoglobin levels than those that fed the control diet (P 150 mg/dL (r = 0.449, P 150 mg/dL, increased cholesterol levels affected erythrocyte membranes and probably reduced their deformability, resulting in decreased hemoglobin levels (anemia) with erythrocyte destruction in the spleen as the rate-determining factor. This decrease was detected as changes in near-infrared light transmission.
- Published
- 2014
186. High repetition pump-and-probe photoemission spectroscopy based on a compact fiber laser system
- Author
-
T. Otsu, Shik Shin, Akira Ozawa, Yukiaki Ishida, Yohei Kobayashi, Koichiro Yaji, and Shuntaro Tani
- Subjects
Materials science ,Physics - Instrumentation and Detectors ,Photoemission spectroscopy ,FOS: Physical sciences ,chemistry.chemical_element ,02 engineering and technology ,01 natural sciences ,Fluence ,law.invention ,Bismuth ,Highly oriented pyrolytic graphite ,law ,Fiber laser ,0103 physical sciences ,010306 general physics ,Instrumentation ,Condensed Matter - Materials Science ,business.industry ,Materials Science (cond-mat.mtrl-sci) ,Instrumentation and Detectors (physics.ins-det) ,021001 nanoscience & nanotechnology ,Laser ,chemistry ,Sapphire ,Optoelectronics ,0210 nano-technology ,business ,Ultrashort pulse ,Optics (physics.optics) ,Physics - Optics - Abstract
The paper describes a time-resolved photoemission (TRPES) apparatus equipped with a Yb-doped fiber laser system delivering 1.2-eV pump and 5.9-eV probe pulses at the repetition rate of 95 MHz. Time and energy resolutions are 11.3 meV and ~310 fs, respectively; the latter is estimated by performing TRPES on a highly oriented pyrolytic graphite (HOPG). The high repetition rate is suited for achieving high signal-to-noise ratio in TRPES spectra, thereby facilitating investigations of ultrafast electronic dynamics in the low pump fluence (p) region. TRPES of polycrystalline bismuth (Bi) at p as low as 30 nJ/mm2 is demonstrated. The laser source is compact and is docked to an existing TRPES apparatus based on a 250-kHz Ti:sapphire laser system. The 95-MHz system is less prone to space-charge broadening effects compared to the 250-kHz system, which we explicitly show in a systematic probe-power dependency of the Fermi cutoff of polycrystalline gold. We also describe that the TRPES response of an oriented Bi(111)/HOPG sample is useful for fine-tuning the spatial overlap of the pump and probe beams even when p is as low as 30 nJ/mm2.
- Published
- 2016
187. Kerr-lens mode locking above a 20 GHz repetition rate
- Author
-
Shota Kimura, Shuntaro Tani, and Yohei Kobayashi
- Subjects
Physics ,Lens (optics) ,Optics ,Repetition (rhetorical device) ,Mode-locking ,Femtosecond pulse ,law ,business.industry ,Physics::Optics ,business ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention - Abstract
We present a compact, Kerr-lens mode-locked oscillator consisting of a three-element optical setup and demonstrate femtosecond pulse generation at a repetition rate of 23.8 GHz.
- Published
- 2019
188. Direct generation of femtosecond vortex beam from a Yb:KYW oscillator featuring a defect-spot mirror
- Author
-
Isao Ito, Sha Wang, Zhigang Zhao, and Yohei Kobayashi
- Subjects
Materials science ,business.industry ,Amplifier ,Physics::Optics ,Pulse duration ,Cladding (fiber optics) ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,Optics ,law ,Fiber laser ,Optical cavity ,Femtosecond ,Physics::Accelerator Physics ,Light beam ,Electrical and Electronic Engineering ,business ,Optical vortex - Abstract
We have demonstrated the first direct femtosecond vortex beam generation from a semiconductor saturable absorber mirror (SESAM) mode locked Yb:KYW oscillator, featuring a homemade defect-spot mirror. Experimentally, a Laguerre Gaussian LG01 vortex beam with a repetition rate of ∼103.5 MHz and a pulse duration of 298 fs has been obtained. Both the defect mirror induced spatial loss modulation and intra-cavity astigmatism are responsible for the doughnut mode generation. Further, the chirality of the vortex beam is controlled by slightly tilting the angle of the Yb:KYW crystal, which hence breaks the azimuthal symmetry inside the laser cavity and leads to differential losses for LG0,+1 and LG0,-1 modes. The potential of the vortex beam’s amplification by a 2-m long Yb-doped double cladding fiber (DCF) amplifier has also been demonstrated.
- Published
- 2019
189. Preface to Special Issue on Development of New Light Sources and Elements Technology for Next-Next-Generation Laser Processing
- Author
-
Yohei Kobayashi
- Subjects
Development (topology) ,Computer science ,Systems engineering ,Laser processing - Published
- 2019
190. Monolithic LiF or MgF2 lens-window-prism device for coherent 10.7 eV beam source with 1 MHz repetition rate
- Author
-
Takeshi Kondo, Ayumi Harasawa, Zhigang Zhao, Kenta Kuroda, Shik Shin, and Yohei Kobayashi
- Subjects
Magnesium fluoride ,Materials science ,business.industry ,Lithium fluoride ,Radiation ,Laser ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,law.invention ,010309 optics ,Lens (optics) ,chemistry.chemical_compound ,Optics ,chemistry ,law ,0103 physical sciences ,Femtosecond ,Prism ,Electrical and Electronic Engineering ,business ,Beam (structure) - Abstract
A monolithic lens-window-prism (LWP) device, made of lithium fluoride (LiF) or magnesium fluoride (MgF2), was proposed. When either of the devices was fixed onto one end of a gas cell filled with Xe, it becomes a “wedge-crystal”-like device and was used to convert a 1 MHz femtosecond 347 nm laser to its third harmonic radiation at 10.7 eV. This led to an improved beam profile and a more compact and less lossy configuration. A stable output power of ∼11 μW was demonstrated for 2 h using LiF-LWP. In addition, MgF2-LWP was also verified for its practicability at 10.7 eV.
- Published
- 2019
191. Research on a debris removal robot
- Author
-
Yohei Kobayashi
- Subjects
Environmental science ,Robot ,Debris ,Marine engineering - Published
- 2019
192. Complexity of Interpersonal Relationship in Team Sports : Ambiguity in Sports
- Author
-
Yohei, Kobayashi
- Published
- 2013
193. Effect of R&D tax credits for SMEs in Japan: a microeconometric analysis focused on liquidity constraints
- Author
-
Yohei Kobayashi
- Subjects
Selection bias ,Microeconomics ,Economics and Econometrics ,Entrepreneurship ,Tax credit ,media_common.quotation_subject ,Propensity score matching ,Economics ,General Business, Management and Accounting ,media_common ,Market liquidity - Abstract
This article estimates the effect of research and development (R&D) tax credits for small- and medium-sized enterprises (SMEs) by utilizing the propensity score matching method to correct any possible selection bias. This study also examines whether the impact of tax credits differs with firms’ characteristics such as their industry, size, and liquidity constraints. Empirical results show that R&D tax credits induce an increase in SMEs’ R&D expenditures. Moreover, we find that the effect of R&D tax credits on liquidity-constrained firms is much greater than on unconstrained firms.
- Published
- 2013
194. Possible presence of hydrophilic SO3H nanoclusters on the surface of dry ultrathin Nafion® films: a positron annihilation study
- Author
-
Seiiti Kuroda, Hamdy F. M. Mohamed, R. Suzuki, N. Oshima, Akihiro Ohira, and Yohei Kobayashi
- Subjects
Materials science ,Silicon ,Analytical chemistry ,General Physics and Astronomy ,chemistry.chemical_element ,Glassy carbon ,Nanoclusters ,Contact angle ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,chemistry ,Nafion ,Annihilation radiation ,Physical and Theoretical Chemistry ,Thin film - Abstract
Solutions of Nafion® with an ion exchange capacity (IEC) of 0.91 meq g(-1), which are on the verge of the formation of SO(3)H nanoclusters, were spin coated on silicon (Si), glassy carbon (GC) and platinum/silicon (Pt/Si) substrates to form films of up to 256 nm thickness. Nanostructure of the films was studied using Doppler broadening of annihilation radiation (DBAR), positron annihilation lifetime (PAL), X-ray photoelectron spectroscopy (XPS), an atomic force microscope (AFM) and contact angle measurements. Contact angles as low as 10 degrees indicate that the surface of dry ultrathin Nafion® films on Si is highly hydrophilic. XPS data of 10 nm thick, ultrathin film on Si show that oxygen concentration is enhanced and the SO(3)H group concentration, in other words, IEC on the surface is much higher than other films. The S parameter measured by DBAR of an ultrathin Nafion® film on Si is much higher than that of the films on the other substrates. We consider that a large number of hydrophilic, reversed micelle like SO(3)H groups are on the surface of the ultrathin Nafion® film on Si but not on the surface of other films. Positrons implanted into the film are trapped by the SO(3)H clusters, annihilating with the electrons of oxygen and exhibit the high S parameter. The SO(3)H concentration on the surface of thin Nafion® films on GC and Pt/Si substrates may not be so high as the threshold for the formation of a large number of SO(3)H clusters. Positrons implanted into the films annihilate mostly with fluorine atoms, resulting in a low S parameter. The film-substrate interaction plays an essential role in nanostructuring of Nafion® thin films, which may also be the case for Nafion® on the catalysts of polymer electrolyte fuel cells.
- Published
- 2013
195. Electroencephalography in DLB
- Author
-
Yukio Kosugi, Toshimitsu Musha, Mieko Tanaka, Yohei Kobayashi, and Haruyasu Matsuzaki
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,Resting state fMRI ,business.industry ,Brain activity and meditation ,Dementia with Lewy bodies ,Alpha (ethology) ,Electroencephalography ,Occipital region ,Audiology ,medicine.disease ,medicine ,Premovement neuronal activity ,Spectral analysis ,business - Abstract
The authors have developed a technology called neuronal activity topography (NAT), using which a pair of markers is obtained by spectral analysis of the electroencephalogram (EEG) of a subject, when he or she is in an awake, resting state with eyes closed, to determine minute differences in his or her brain activity. The markers provide a numerical index indicating the degree to which the subject resembles the average patterns of certain brain disorders. NAT images obtained from a group of patients with dementia with Lewy bodies (DLB) displayed such average features as the presence of slow-wave activity in the temporoparietal lobes in the occipital region and diffuse alpha, both of which were found to be more pronounced compared to a group of patients with Alzheimer’s disease. The tendencies agree with features observed by EEG visual inspection. Using this technology, it was possible to distinguish between cognitively normal subjects and DLB patients with 95 % accuracy.
- Published
- 2016
196. Range limitation in hip internal rotation and fifth metatarsal stress fractures (Jones fracture) in professional football players
- Author
-
Keiji Kobayashi, Hiroshi Ikeda, Yohei Kobayashi, Hiroki Nakajima, Kazuo Kaneko, Takayuki Kawasaki, Masashi Nagao, Yoshitomo Saita, and Yuji Takazawa
- Subjects
Adult ,Male ,medicine.medical_specialty ,Fractures, Stress ,Rotation ,Logistic regression ,Jones fracture ,03 medical and health sciences ,Fractures, Bone ,Young Adult ,0302 clinical medicine ,Japan ,Risk Factors ,Fifth metatarsal bone ,Soccer ,medicine ,Humans ,Orthopedics and Sports Medicine ,Risk factor ,Metatarsal Bones ,030222 orthopedics ,Stress fractures ,business.industry ,030229 sport sciences ,Odds ratio ,medicine.disease ,Confidence interval ,medicine.anatomical_structure ,Logistic Models ,Case-Control Studies ,Physical therapy ,Surgery ,Hip Joint ,business ,Body mass index - Abstract
To identify unknown risk factors associated with fifth metatarsal stress fracture (Jones fracture). A case–controlled study was conducted among male Japanese professional football (soccer) players with (N = 20) and without (N = 40) a history of Jones fracture. Injury history and physical examination data were reviewed, and the two groups were compared. Univariate and multivariate logistic regression controlling for age, leg dominance and body mass index were used to obtain odds ratios (ORs) and 95% confidence intervals (CIs) to describe the association between physical examination data and the presence or absence of Jones fractures. From 2000 to 2014, among 162 professional football club players, 22 (13.6%; 21 Asians and one Caucasian) had a history of Jones fracture. Thirteen out of 22 (60%) had a Jones fracture in their non-dominant leg. The mean range of hip internal rotation (HIR) was restricted in players with a history of Jones fracture [25.9° ± 7.5°, mean ± standard deviation (SD)] compared to those without (40.4° ± 11.1°, P
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- 2016
197. Phase-matched frequency conversion below 150 nm in KBe
- Author
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Tomoharu, Nakazato, Isao, Ito, Yohei, Kobayashi, Xiaoyang, Wang, Chuangtian, Chen, and Shuntaro, Watanabe
- Abstract
Sum frequency mixing has been demonstrated below 150 nm in KBeBO
- Published
- 2016
198. Impact of Drug-Eluting Stent Implantation for Femoropopliteal In-Stent Occlusion
- Author
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Yoshimitsu Soga, Kenji Ando, Yusuke Tomoi, Seiichi Hiramori, Tatsuya Shiraki, Osamu Iida, and Yohei Kobayashi
- Subjects
Male ,Time Factors ,Databases, Factual ,medicine.medical_treatment ,Constriction, Pathologic ,Kaplan-Meier Estimate ,030204 cardiovascular system & hematology ,Balloon ,0302 clinical medicine ,Restenosis ,Japan ,Recurrence ,Risk Factors ,Occlusion ,Popliteal Artery ,030212 general & internal medicine ,Aged, 80 and over ,medicine.diagnostic_test ,Drug-Eluting Stents ,Middle Aged ,Femoral Artery ,Treatment Outcome ,Drug-eluting stent ,Retreatment ,Female ,Stents ,Radiology ,Cardiology and Cardiovascular Medicine ,medicine.medical_specialty ,Prosthesis Design ,Disease-Free Survival ,03 medical and health sciences ,Peripheral Arterial Disease ,Angioplasty ,medicine ,Alloys ,Humans ,Radiology, Nuclear Medicine and imaging ,Aged ,Proportional Hazards Models ,Retrospective Studies ,Chi-Square Distribution ,business.industry ,Stent ,medicine.disease ,Surgery ,Stenosis ,Angiography ,business ,Angioplasty, Balloon - Abstract
Purpose: To compare optimal balloon angioplasty with nitinol stenting and drug-eluting stent (DES) implantation for femoropopliteal in-stent occlusion (ISO). Methods: A dual center, retrospective study was performed from January 2004 to December 2014 encompassing 110 ISOs after bare nitinol stenting for a femoropopliteal lesion in 100 patients (mean age 72.7±10.1 years; 58 men). These patients underwent optimal balloon angioplasty with implantation of a bare stent (conventional group, n=79) or a DES (n=21). The primary endpoint was recurrent in-stent restenosis (Re-ISR); secondary endpoints were recurrent target lesion revascularization (Re-TLR), reocclusion, and major adverse limb events (MALE). Re-ISR or reocclusion was defined as ISR or occlusion after TLR. Restenosis was defined as a peak systolic velocity ratio >2.4 on a duplex scan or >50% stenosis on angiography. Univariate Cox regression analysis was used to identify any relationships between patient and procedure variables and the occurrence of Re-ISR; the results are presented as the hazard ratio (HR) and the 95% confidence interval (CI). Results: The mean follow-up period was 34.9±27.4 months. At 2 years, Kaplan-Meier estimated freedom from Re-ISR rates were 79.3% in the DES group and 20.2% in the conventional group, respectively (p
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- 2016
199. Development of high coherence high power 193nm laser
- Author
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Satoshi Tanaka, Masaki Arakawa, Yasuhiro Kamba, Koji Kakizaki, Takashi Onose, Hironori Igarashi, Chen Qu, Hongwen Xuan, Atsushi Fuchimukai, Hiroaki Oizumi, Yohei Kobayashi, Mitsuru Tamiya, Shinji Ito, Hakaru Mizoguchi, Zhigang Zhao, and Yoichi Sasaki
- Subjects
Argon fluoride laser ,Distributed feedback laser ,Active laser medium ,Materials science ,business.industry ,Far-infrared laser ,02 engineering and technology ,Laser pumping ,021001 nanoscience & nanotechnology ,Laser ,01 natural sciences ,law.invention ,010309 optics ,Laser linewidth ,Optics ,law ,0103 physical sciences ,Optoelectronics ,Laser power scaling ,0210 nano-technology ,business - Abstract
We have been developing a hybrid 193 nm ArF laser system that consists of a solid state seeding laser and an ArF excimer laser amplifier for power-boosting. The solid state laser consists of an Yb-fiber-solid hybrid laser system and an Er-fiber laser system as fundamentals, and one LBO and three CLBO crystals for frequency conversion. In an ArF power amplifier, the seed laser passes through the ArF gain media three times, and an average power of 110 W is obtained. As a demonstration of the potential applications of the laser, an interference exposure test is performed.
- Published
- 2016
200. Bidirectional Kerr-lens mode-locked dual-comb ring laser
- Author
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Yohei Kobayashi, Tasuku Nakamura, Keisuke Goda, and Takuro Ideguchi
- Subjects
Physics ,Absorption spectroscopy ,business.industry ,Feedback control ,Ring laser ,01 natural sciences ,Fourier transform spectroscopy ,law.invention ,010309 optics ,Lens (optics) ,Optics ,law ,0103 physical sciences ,010306 general physics ,Spectroscopy ,business - Abstract
We demonstrate a bidirectional Kerr-lens mode-locked dual-comb ring laser for simple and robust dual-comb spectroscopy. Two mutually coherent combs with slightly different repetition rates emitted from the single cavity enables dual-comb spectroscopy without feedback control.
- Published
- 2016
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