1,837 results on '"K Ogura"'
Search Results
2. In-vacuum post-compression of optical probe pulses for relativistic plasma diagnostics
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S. Lorenz, G. M. Grittani, K. Kondo, A. Kon, Y.-K. Liu, A. Sagisaka, K. Ogura, N. Nakanii, K. Huang, A. Bierwage, S. Namba, H. Ohiro, T. A. Pikuz, J. K. Koga, P. Chen, H. Kiriyama, M. Kando, T. Zh. Esirkepov, S. V. Bulanov, and A. S. Pirozhkov
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compression after compressor approach ,probe pulse post-compression ,relativistic plasma imaging ,ultrafast optical probing ,Applied optics. Photonics ,TA1501-1820 - Abstract
Ultrafast optical probing is a widely used method of underdense plasma diagnostic. In relativistic plasma, the motion blur limits spatial resolution in the direction of motion. For many high-power lasers the initial pulse duration of 30–50 fs results in a 10–15 μm motion blur, which can be reduced by probe pulse post-compression. Here we used the compression after compressor approach [Phys.-Usp. 62, 1096 (2019); JINST 17 P07035 (2022)], where spectral broadening is performed in thin optical plates and is followed by reflections from negative-dispersion mirrors. Our initially low-intensity probe beam was down-collimated for a more efficient spectral broadening and higher probe-to-self-emission intensity ratio. The setup is compact, fits in a vacuum chamber and can be implemented within a short experimental time slot. We proved that the compressed pulse retained the high quality necessary for plasma probing.
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- 2024
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3. Metrology for sub-Rayleigh-length target positioning in ∼1022 W/cm2 laser–plasma experiments
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E. A. Vishnyakov, A. Sagisaka, K. Ogura, T. Zh. Esirkepov, B. Gonzalez-Izquierdo, C. D. Armstrong, T. A. Pikuz, S. A. Pikuz, W. Yan, T. M. Jeong, S. Singh, P. Hadjisolomou, O. Finke, G. M. Grittani, M. Nevrkla, C. M. Lazzarini, A. Velyhan, T. Hayakawa, Y. Fukuda, J. K. Koga, M. Ishino, K. Kondo, Y. Miyasaka, A. Kon, M. Nishikino, Y. V. Nosach, D. Khikhlukha, I. P. Tsygvintsev, D. Kumar, J. Nejdl, D. Margarone, P. V. Sasorov, S. Weber, M. Kando, H. Kiriyama, Y. Kato, G. Korn, S. V. Bulanov, T. Kawachi, and A. S. Pirozhkov
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laser–plasma interaction ,precise target positioning ,spectroscopy ,ultra-high intensity ,X-rays ,Applied optics. Photonics ,TA1501-1820 - Abstract
Tight focusing with very small f-numbers is necessary to achieve the highest at-focus irradiances. However, tight focusing imposes strong demands on precise target positioning in-focus to achieve the highest on-target irradiance. We describe several near-infrared, visible, ultraviolet and soft and hard X-ray diagnostics employed in a ∼1022 W/cm2 laser–plasma experiment. We used nearly 10 J total energy femtosecond laser pulses focused into an approximately 1.3-μm focal spot on 5–20 μm thick stainless-steel targets. We discuss the applicability of these diagnostics to determine the best in-focus target position with approximately 5 μm accuracy (i.e., around half of the short Rayleigh length) and show that several diagnostics (in particular, 3 $\omega$ reflection and on-axis hard X-rays) can ensure this accuracy. We demonstrated target positioning within several micrometers from the focus, ensuring over 80% of the ideal peak laser intensity on-target. Our approach is relatively fast (it requires 10–20 laser shots) and does not rely on the coincidence of low-power and high-power focal planes.
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- 2024
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4. Large-scale star formation in Auriga region
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A K Pandey, Saurabh Sharma, N Kobayashi, Y Sarugaku, and K Ogura
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- 2019
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5. Rapid Decrease of HbA1c by Imeglimin (Twymeeg) in Patient with Obesity and Type 2 Diabetes (T2D)
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H, Bando, primary, Y, Kato, additional, H, Yamashita, additional, and K, Ogura, additional
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- 2023
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6. Magnetization Analysis of Magnetic Nanowire Memory Utilizing Two Recording Metal Wires for Low Current Recording
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K. Ogura, M. Takahashi, N. Nakatani, N. Ishii, and Y. Miyamoto
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Electrical and Electronic Engineering ,Condensed Matter Physics ,Instrumentation ,Electronic, Optical and Magnetic Materials - Published
- 2022
7. Trends and outcomes of early rehabilitation in intensive care unit for patients with cardiovascular disease – a cohort study with propensity score-matched analysis
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N Hamazaki, K Kamiya, K Nozaki, M Yamashita, S Uchida, T Noda, K Ogura, D Nagumo, E Maekawa, M Yamaoka-Tojo, A Matsunaga, T Kitamura, J Ako, and K Miyaji
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Cardiology and Cardiovascular Medicine - Abstract
Background Early rehabilitation in the intensive care unit (ICU), including early mobility therapy, is known to improve the clinical outcomes in patients with critically ill. However, the effectiveness of acute-phase cardiovascular rehabilitation (CR) during ICU treatment have not been thoroughly evaluated in patients with cardiovascular disease (CVD). Purpose We aimed to investigate the trends and outcomes of acute-phase CR in the ICU for patients with CVD, including in-hospital and long-term clinical outcomes. Methods We reviewed 1948 consecutive patients with CVD admitted to tertiary academic ICU at a university hospital. Patients were arbitrarily assessed by an ICU team consisting of medical and surgical doctors, nurses and physiotherapists within 24 hours after admission to ICU to discover whether their rehabilitation could be initiated according to the specific clinical trial and statement. As clinical characteristics, disease aetiology, comorbid conditions, and ICU treatment were obtained from an electronic database. We evaluated the probability of return to walking independence and return to home as in-hospital clinical outcomes. All patients were followed for five years and investigated all-cause and cardiovascular events after hospital discharge as long-term clinical outcomes. The associations between the implementation of CR during ICU treatment (ICU-CR) and clinical outcomes were evaluated using propensity score-matched analysis with adjustment for clinical characteristics in all matched patients and various subgroups, including aged >65 years, surgical patients, emergency, and length of ICU stay ≥48 hours. Results Out of studied patients, 1092 patients received ICU-CR, the number of which positively correlated with year-trend (r=0.986, P Conclusions The implementation of acute-phase CR in the ICU increased with year-trend, considered beneficial to improve in-hospital and long-term clinical outcomes in patients with CVD and various subgroups of relatively severe disease conditions. Funding Acknowledgement Type of funding sources: None.
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- 2022
8. The vascular response to ultrathin biodegradable polymer sirolimus-eluting stent at 2-weeks and 1-year follow up in patients with ST-elevation myocardial infarction
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Y Oishi, H Tsujita, T Arai, R Sakai, S Sato, H Tanaka, K Ogura, R Masaki, S Kondo, S Tsukamoto, S Higuchi, A Sumida, H Matsumoto, and T Shinke
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Cardiology and Cardiovascular Medicine - Abstract
Background Recent clinical study suggests newer-generation drug-eluting stents (DES) that combine ultrathin strut and nano-coating with biodegradable polymers sirolimus-eluting stent (BP-SES) could improve long-term clinical outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) over current generation DES. However, the details of vascular response in very early and chronic phase have not been systematically addressed. Objective and method We exploratory investigate early and chronic vascular response following BP-SES implantation in patients with STEMI to reveal mechanism of the favorable clinical outcomes in recent studies using frequency domain-optical coherence tomography (FD-OCT). Consecutive twenty-four patients with STEMI who underwent FD-OCT after primary PCI and were eligible for follow-up FD-OCT at 2 weeks and 1 year after implantation were enrolled between June 2018 and August 2020. OCT was performed immediately after PCI, at 2-weeks (2W) and 1-year (1Y) after the primary PCI. Struts were recorded as uncovered if any part was visibly exposed in the lumen or covered if a layer of tissue covered all reflecting surfaces. Struts of stents that are smaller than 3.0mm of diameter with more than 80μm between the center reflection and the adjacent vessel surface were recorded as malapposed. The reduction of atherothrombotic protrusion burden within the stent was also assessed. Results Twenty-four patients (age 64.9±11.4 years, male 83.3%) were enrolled. The percentage of uncovered struts significantly decreased from post-PCI to 2W follow-up and from 2W follow-up to 1Y follow-up (62±20% post-PCI versus 27±11% at 2W follow up, p Conclusion(s) This study elucidated very early and chronic vascular responses following ultrathin strut BP-SES implantation in STEMI patients by FD-OCT. It showed resolution of athero-thrombotic materials in very early phase and favorable progression of strut coverage in very early and chronic phase. Funding Acknowledgement Type of funding sources: None.
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- 2022
9. Perme ICU Mobility Score as a comprehensive assessment tool of acute-phase rehabilitation is correlated with clinical outcomes in patients after cardiovascular surgery
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K Ogura, N Hamazaki, K Kamiya, T Kitamura, S Kobayashi, T Ichikawa, M Yamashita, S Uchida, T Noda, D Nagumo, E Maekawa, M Yamaoka-Tojo, A Matsunaga, J Ako, and K Miyaji
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Cardiology and Cardiovascular Medicine - Abstract
Background Early mobility therapy in the intensive care unit (ICU) is widely employed to improve the physical function and prognosis of patients with critically ill. On the other hand, patients who undergo cardiovascular surgery frequently suffer from disabilities after ICU care due to their cardiopulmonary conditions and treatments. However, few studies have reported the procedures and assessments of acute-phase rehabilitation in these patients. Recently, the Perme ICU Mobility Score (Perme Score) was developed as a reliable tool to assess comprehensive mobility status of patients in the ICU. We hypothesised that the Perme Score is a useful tool for assessing the mobility levels in the ICU and predicting clinical outcomes in patients undergoing acute-phase rehabilitation after cardiovascular surgery. Purpose To investigate the associations between the Perme Score within the second days after cardiovascular surgery and the patients' clinical outcomes, including physical function and the incidence of clinical events. Methods We studied 224 consecutive patients (34.4% female; aged 65±13 years) who were admitted to the ICU of a tertiary academic hospital after cardiac and/or major vascular surgery. Clinical characteristics including patient profiles, comorbidities, surgical details and APACHE II and SOFA scores were evaluated on ICU admission. The Perme Score contains categories on mental status, potential mobility barriers, muscle strength and mobility level, with higher scores indicating greater activity levels in the ICU. We assessed the Perme Score within the second days after the surgery. As a physical function at hospital discharge, we measured the six-minute walk distance (6MWD). The primary endpoint was a composite outcome of the number of all-cause mortality and/or all-cause unplanned readmission. We analysed the associations of the Perme Score with the 6MWD and the incidence of clinical events using multiple regression analysis and multivariate Poisson regression analysis, respectively. Results After adjusting for clinical confounding factors, a higher Perme Score was an independent factor of a higher 6MWD (Table 1). During the median follow-up period of 1.3 years, 51 cases of all-cause mortality/readmission occurred in 37 (16.5%) patients, with an incidence rate of 18.6/100 person-years. In the multivariate Poisson regression analysis, even after adjusting for the severity score in the ICU, a higher Perme Score was significantly and independently associated with lower rates of all-cause clinical events (adjusted incident rate ratio: 0.96, 95% confidence interval: 0.93–0.99, P=0.008, Figure 1). Conclusions The Perme Score within the second days after cardiovascular surgery is correlated with physical function at hospital discharge and the incidence of clinical events after discharge. Thus, a comprehensive assessment of acute-phase rehabilitation after cardiovascular surgery may be useful in predicting clinical outcomes. Funding Acknowledgement Type of funding sources: None.
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- 2022
10. Impact of small-airway disease on exercise intolerance and long-term outcomes in patients with heart failure and reduced or preserved ejection fraction
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D Nagumo, N Hamazaki, K Kamiya, S Obara, S Kobayashi, K Nozaki, T Ichikawa, M Yamashita, S Uchida, T Noda, K Ogura, E Maekawa, M Yamaoka-Tojo, A Matsunaga, and J Ako
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Cardiology and Cardiovascular Medicine - Abstract
Introduction Exercise intolerance in patients with heart failure (HF) is a strong indicator of a poor prognosis. As the respiratory impairment in HF patients, the small airway is reportedly more susceptible than central airways, which results in increased airway resistance and may cause poor outcomes. However, the impact of small-airway disease (SAD) on exercise intolerance and prognosis in patients with HF is still unclear. Purpose We investigated the associations between SAD and exercise intolerance in patients with HF, and the clinical significance of SAD for long-term clinical events with a reduced or preserved ejection fraction. Methods We reviewed 1015 patients with HF (mean age, 66.9±14.6 years; male, 64.5%) admitted for medical treatment. Patients with a prior history of chronic respiratory disease or an obstructive lung pattern – defined as the forced expiratory volume (%) in 1 s relative to Result SAD was observed in 479 (47.2%) patients. LVEF subgroups included 458 (45.1%) and 518 (51.0%) patients with LVEF Conclusion This study is the first to reveal that SAD is associated with exercise intolerance in patients with HF regardless of LVEF. Moreover, SAD may have a predictive significance for long-term outcomes in patients with HF and subgroups with reduced, but not preserved ejection fraction. Funding Acknowledgement Type of funding sources: None.
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- 2022
11. 126P Comprehensive efforts to address multifaceted issues of rare cancers and sarcomas in Japan
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A. Kawai, S. Iwata, T. Shimoi, E. Kobayashi, K. Ogura, A. Yoshida, H.S. Okuma, Y. Goto, C. Morizane, Y. Yoshida, Y. Katoh, Y. Yatabe, K. Yonemori, K. Nakamura, T. Nishida, and T. Higashi
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Cancer Research ,Oncology - Published
- 2023
12. Cesium concentrations in various environmental media at Namie, Fukushima
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Ryohei Yamada, Hirofumi Tazoe, Naofumi Akata, K. Ogura, Takahito Suzuki, Yoshitaka Shiroma, Masahiro Hosoda, Takakiyo Tsujiguchi, Masaru Yamaguchi, Ikuo Kashiwakura, Kazuki Iwaoka, Shinji Tokonami, Miklós Hegedűs, and Yuki Tamakuma
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inorganic chemicals ,Health, Toxicology and Mutagenesis ,Public Health, Environmental and Occupational Health ,Sediment ,chemistry.chemical_element ,Environmental media ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Pollution ,0104 chemical sciences ,Analytical Chemistry ,Nuclear Energy and Engineering ,chemistry ,Environmental chemistry ,Caesium ,Environmental science ,Radiology, Nuclear Medicine and imaging ,Spectroscopy - Abstract
The radioactivity of cesium in the water and sediments of two major rivers was measured along with airborne radioactivity in Namie Town, after the recent partial lift on the evacuation order in 2017. The observed concentrations were up to 384 ± 11 mBq/L for 137Cs in unfiltered water and 1.28 ± 0.09 mBq m−3 for 137Cs in air, while the sediment had a maximum of 44,900 ± 23 Bq kg−1 for 137Cs. The potential yearly committed effective dose was estimated based on the data.
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- 2020
13. Significant Reduction of Body Weight and Blood Glucose by Oral Semaglutide (Rybelsus) for Type 2 Diabetes (T2D) Patient
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H, Yamashita, primary, H, Bando, additional, Y, Kato, additional, K, Ogura, additional, and T, Kawata, additional
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- 2022
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14. Clinical Improvement of Weight, HbA1c and Liver Function by Rybelsus (Oral Semaglutide) In Patient with Type 2 Diabetes (T2D), Obesity and Fatty Liver
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H, Yamashita, primary, H, Bando, additional, Y, Kato, additional, K, Ogura, additional, and E, Sueki, additional
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- 2022
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15. Augmentation of Articulate Data using 3D Image Analysis
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H, Bando, primary, K, Ogura, additional, T, Obonai, additional, T, Kawata, additional, and Y, Kato, additional
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- 2022
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16. Remarkable Efficacy of Blood Glucose and Weight by Oral Semaglutide (Rybelsus) For Short Period
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H, Bando, primary, H, Yamashita, additional, Y, Kato, additional, K, Ogura, additional, and T, Kawata, additional
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- 2022
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17. Detail Analysis of Peripheral Artery Disease (PAD) Using SYNAPSE VINCENT Technology
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K, Ogura, primary, H, Bando, additional, S, Nishikawa, additional, Y, Kato, additional, and T, Obonai, additional
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- 2022
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18. Higher plasma level of small dense low-density lipoprotein cholesterol in ST-segment-elevation myocardial infarction patients with plaque rupture
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T Arai, T Sekimoto, H Mori, R Sakai, H Tanaka, Y Oishi, K Ogura, K Nomura, K Sakai, H Tsujita, S Kondo, S Koba, and T Shinke
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Cardiology and Cardiovascular Medicine - Abstract
Aim The aim of this study was to compare small dense low-density lipoprotein cholesterol (sd-LDL-c) and various lipid markers between patients exhibiting plaque rupture (PR) in the culprit lesions evaluated by optical coherence tomography (OCT) imaging and those without PR in ST-segment elevation myocardial infarction (STEMI) patients. Methods We studied consecutive 60 de novo culprit lesions in 60 patients with STEMI who underwent pre-intervention OCT. PR was defined as a plaque containing a cavity that had overlying residual fibrous caps. Plasma sd-LDL-c was measured directly by homogeneous assay at the time of primary percutaneous coronary intervention. Results The patients were classified into PR (n=40, 66.7%) or non-PR (n=20, 33.3%). There were no significant differences in low-density lipoprotein cholesterol (LDL-c), non-high-density lipoprotein cholesterol (non-HDL-c) and pre-admission statin therapy between two groups (135.1±38.0 mg/dL vs 129.2±43.8 mg/dL; p=0.35, 157.1±37.4 mg/dL vs 143.0±37.7 mg/dL; p=0.24, 15.0% vs 20.0%; p=0.93). However, sd-LDL-c level was significantly higher in patients with PR than those with non-PR (44.0±18.1 mg/dL vs 28.0±9.3 mg/dL; p=0.0005). On multiple logistic regression analysis, sd-LDL-c was an independent predictor of PR (odds ratio, 1.14 per 1 mg/dL; p=0.0063). Conclusion Sd-LDL-c was significantly associated with PR of the culprit lesion in patients with STEMI. Funding Acknowledgement Type of funding sources: None.
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- 2021
19. Robotic utterance style to promote conversation with older people in Japan
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H. Shimoyama, K. Ogura, M. Hirano, M. Nakano, Y. Iwano, D. Sakamoto, and T. Tsuchida
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media_common.quotation_subject ,Biomedical Engineering ,Conversation ,Geriatrics and Gerontology ,Older people ,Psychology ,Gerontology ,Utterance ,Linguistics ,Style (sociolinguistics) ,media_common - Published
- 2019
20. Enhanced diagnostics of radiating relativistic singularities and BISER by nonlinear post-compression of optical probe pulse
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A.V. Kotov, T.Zh. Esirkepov, A.A. Soloviev, A. Sagisaka, K. Ogura, A. Bierwage, M. Kando, H. Kiriyama, M.V. Starodubtsev, E.A. Khazanov, S.Yu. Mironov, and A.S. Pirozhkov
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Instrumentation ,Mathematical Physics - Abstract
The enhancement of the resolution of pump-probe optical diagnostics for ultrafast processes by compressing the probe pulse duration using the CafCA approach [1] is considered on an example of the BISER soft-X-ray generation [2] with the J-KAREN-P laser [3].
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- 2022
21. Cepharanthine induces the proliferation of human dermal papilla cells and stimulates vascular endothelial growth factor expression through increased intracellular calcium mobilization and hypoxia-inducible factor activation
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K. Ogura, K. Tamba, A. Kiso, M. Sugano, Y. Tsunekawa, K. Hagiwara, and T. Iwabuchi
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Vascular Endothelial Growth Factor A ,Alopecia Areata ,Dermatology ,Outer root sheath ,Real-Time Polymerase Chain Reaction ,Benzylisoquinolines ,Calcium in biology ,Cell Line ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cepharanthine ,Humans ,Cell Proliferation ,Skin ,Molecular Structure ,Chemistry ,Anti-Inflammatory Agents, Non-Steroidal ,In vitro ,Cell biology ,Vascular endothelial growth factor ,Hypoxia-inducible factors ,030220 oncology & carcinogenesis ,Human hair growth ,Calcium ,Intracellular ,Hair - Abstract
Background Cepharanthine (CEP), a compound extracted from the vine Stephania cephalantha, is commonly prescribed to treat alopecia areata; however, the scientific evidence for its efficacy is limited. Aim To investigate the effect of CEP and its structural analogues on human hair growth in vitro. Methods The effects of CEP and three of its structural analogues on the proliferation of human dermal papilla cells (hDPCs) and human outer root sheath cells (hORSCs) were investigated. Their effects on vascular endothelial growth factor (VEGF) expression were also assessed by real-time PCR. Activation of pathways leading to VEGF expression, such as intracellular Ca2+ mobilization and hypoxia-inducible factor (HIF) expression, was also characterized. Results CEP and two of its structural analogues significantly stimulated the growth of hDPCs but not hORSCs. Moreover, CEP and all three structural analogues significantly induced the expression of VEGF in hDPCs. CEP increased the intracellular Ca2+ concentration in hDPCs. CEP also increased the expression of HIF-1α and HIF-2α and induced the expression of HIF-responsive genes in hDPCs, even under normoxia. Conclusions These results suggest that CEP and its structural analogues have the potential to restore hair growth by promoting the proliferation of hDPCs and increasing their expression of VEGF.
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- 2020
22. Changed Diabetic Treatment from Multiple Daily Injection (MDI), Dulaglutide to Xultophy
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H, Bando, primary, Y, Kato, additional, S, Matsuzaki, additional, S, Waka, additional, and K, Ogura, additional
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- 2021
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23. A History of JEOL Field Emission Scanning Electron Microscopes with Reference to Biological Applications
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Andrew Yarwood and K Ogura
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Field electron emission ,Materials science ,Optics ,Scanning electron microscope ,business.industry ,business - Published
- 2019
24. Ultra-relativistic Fe plasma with gj/cm3 energy density created by femtosecond laser pulses
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M. A. Alkhimova, A. Ya. Faenov, T. A. Pikuz, I. Yu. Skobelev, S. A. Pikuz, M. Nishiuchi, H. Sakaki, A. S. Pirozhkov, A. Sagisaka, N. P. Dover, Ko. Kondo, K. Ogura, Y. Fukuda, H. Kiriyama, M. Kando, R. Kodama, and K. Kondo
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- 2019
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25. Coherent x-ray emission from relativistic plasma singularities (biser)
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A. S. Pirozhkov, T. Zh. Esirkepov, A. Sagisaka, K. Ogura, T. A. Pikuz, A. Ya. Faenov, B. González-Izquierdo, J. K. Koga, H. Kiriyama, N. Nakanii, K. Huang, Y. Fukuda, E. N. Ragozin, D. Neely, H. Daido, Y. Kato, K. Kondo, T. Kawachi, S. V. Bulanov, and M. Kando
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- 2019
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26. Discovery of burst intensification by singularity emitting radiation (biser)
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A. S. Pirozhkov, T. Zh. Esirkepov, A. Ya. Faenov, T. A. Pikuz, A. Sagisaka, K. Ogura, J. K. Koga, H. Kiriyama, Y. Fukuda, E. N. Ragozin, D. Neely, K. Kondo, T. Kawachi, H. Daido, Y. Kato, M. Kando, and S. V. Bulanov
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- 2019
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27. Towards a Novel Laser-Driven Method of Exotic Nuclei Extraction-Acceleration for Fundamental Physics and Technology
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M. Nishiuchi, H. Sakaki, T. Zh. Esirkepov, K. Nishio, T. A. Pikuz, A. Ya. Faenov, I. Yu. Skobelev, R. Orlandi, A. S. Pirozhkov, A. Sagisaka, K. Ogura, M. Kanasaki, H. Kiriyama, Y. Fukuda, H. Koura, M. Kando, T. Yamauchi, Y. Watanabe, S. V. Bulanov, K. Kondo, K. Imai, and S. Nagamiya
- Published
- 2016
28. Ultra-intense K-shell emission from stainless steel foils irradiated by femtosecond laser pulses with ultra-high intensity (i ≥ 1021 W/cm2)
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M. A. Alkhimova, A. Ya. Faenov, T. A. Pikuz, I. Yu. Skobelev, S. A. Pikuz, M. Nishiuchi, H. Sakaki, A. S. Pirozhkov, A. Sagisaka, N. P. Dover, Ko. Kondo, K. Ogura, Y. Fukuda, H. Kiriyama, T. Esirkepov, S. V. Bulanov, M. Kando, K. Nishitani, T. Miyahara, Y. Watanabe, R. Kodama, and K. Kondo
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- 2018
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29. Measured and simulated transport of 1.9 MeV laser-accelerated proton bunches through an integrated test beam line at 1 Hz
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M. Nishiuchi, H. Sakaki, T. Hori, P. R. Bolton, K. Ogura, A. Sagisaka, A. Yogo, M. Mori, S. Orimo, A. S. Pirozhkov, I. Daito, H. Kiriyama, H. Okada, S. Kanazawa, S. Kondo, T. Shimomura, M. Tanoue, Y. Nakai, H. Sasao, D. Wakai, H. Daido, K. Kondo, H. Souda, H. Tongu, A. Noda, Y. Iseki, T. Nagafuchi, K. Maeda, K. Hanawa, T. Yoshiyuki, and T. Shirai
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Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
A laser-driven repetition-rated 1.9 MeV proton beam line composed of permanent quadrupole magnets (PMQs), a radio frequency (rf) phase rotation cavity, and a tunable monochromator is developed to evaluate and to test the simulation of laser-accelerated proton beam transport through an integrated system for the first time. In addition, the proton spectral modulation and focusing behavior of the rf phase rotation cavity device is monitored with input from a PMQ triplet. In the 1.9 MeV region we observe very weak proton defocusing by the phase rotation cavity. The final transmitted bunch duration and transverse profile are well predicted by the PARMILA particle transport code. The transmitted proton beam duration of 6 ns corresponds to an energy spread near 5% for which the transport efficiency is simulated to be 10%. The predictive capability of PARMILA suggests that it can be useful in the design of future higher energy transport beam lines as part of an integrated laser-driven ion accelerator system.
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- 2010
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30. Generation of stable and low-divergence 10-MeV quasimonoenergetic electron bunch using argon gas jet
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M. Mori, K. Kondo, Y. Mizuta, M. Kando, H. Kotaki, M. Nishiuchi, M. Kado, A. S. Pirozhkov, K. Ogura, H. Sugiyama, S. V. Bulanov, K. A. Tanaka, H. Nishimura, and H. Daido
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Nuclear and particle physics. Atomic energy. Radioactivity ,QC770-798 - Abstract
The pointing stability and divergence of a quasimonoenergetic electron bunch generated in a self-injected laser-plasma acceleration regime using 4 TW laser is studied. A pointing stability of 2.4 mrad root-mean-square (rms) and a beam divergence of 10.6 mrad (rms) were obtained using an argon gas-jet target for 50 sequential shots, while these values were degraded by a factor of 3 at the optimum condition using helium. The peak electron energies were 8.5±0.7 and 24.8±3.6 MeV using argon and helium, respectively. The experimental results indicate that the different propagation condition could be generated with the different material, although it is performed with the same irradiation condition.
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- 2009
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31. Abnormal neutrophil scattergram obtained using Pentra MS CRP in the patients with myelodysplastic syndrome showing dysgranulopoiesis
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K. Saito, Yumiko Fujitomo, S. Yuasa, Katsutoshi Ishizuka, T. Kohno, K. Ogura, Tohru Inaba, N. Mishima, Masaki Nakanishi, and Naohisa Fujita
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Male ,medicine.medical_specialty ,Pathology ,Neutrophils ,Clinical Biochemistry ,Leukocyte Count ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Internal medicine ,White blood cell ,Humans ,Medicine ,Aged ,Aged, 80 and over ,Myelopoiesis ,Abnormal Neutrophil ,Hematology ,business.industry ,Myelodysplastic syndromes ,Biochemistry (medical) ,General Medicine ,Middle Aged ,medicine.disease ,Peripheral blood ,Staining ,medicine.anatomical_structure ,chemistry ,Myelodysplastic Syndromes ,030220 oncology & carcinogenesis ,Cytochemistry ,Female ,Sudan Black B ,business ,Granulocytes ,030215 immunology - Abstract
Summary Introduction Pentra MS CRP is an automated hematology analyzer capable of cytochemistry using Chlorazol black E, a lipid-staining agent, for white blood cell (WBC) differentials. Pentra MS CRP displays a WBC scattergram according to the cell volume obtained using flow impedance and light absorbance reflecting the Chlorazol black E (CBE)-positive lipid content. Method Neutrophil scattergrams obtained using Pentra MS CRP were compared between 5 patients with myelodysplastic syndrome (MDS) and normal controls. Sudan black B (SBB)-staining patterns of peripheral blood neutrophils were subdivided into four types (types I, II, III, and VI) based on their staining intensity and scored by counting 200 cells. Such SBB scores were also compared between the two groups. Results Neutrophil scattergrams deviated downward in the MDS group, suggesting the decreased CBE positivity that seemed reflect the reduction of the lipid content in dysplastic neutrophils. SBB scores determined in this study were also decreased in the MDS group when compared with those in normal controls. Conclusion Pentra MS CRP might rapidly generate useful information on dysplastic neutrophils in patients with MDS based on its cytochemistry for WBC differentials during routine laboratory hematology.
- Published
- 2015
32. Scintillator-based transverse proton beam profiler for laser-plasma ion sources
- Author
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N. P. Dover, M. Nishiuchi, H. Sakaki, M. A. Alkhimova, A. Ya. Faenov, Y. Fukuda, H. Kiriyama, A. Kon, K. Kondo, K. Nishitani, K. Ogura, T. A. Pikuz, A. S. Pirozhkov, A. Sagisaka, and M. Kando
- Subjects
Physics ,Beam diameter ,Range (particle radiation) ,Proton ,Physics::Instrumentation and Detectors ,business.industry ,Detector ,Scintillator ,Laser ,01 natural sciences ,010305 fluids & plasmas ,law.invention ,Transverse plane ,Optics ,law ,0103 physical sciences ,Physics::Accelerator Physics ,010306 general physics ,business ,Instrumentation ,Beam (structure) - Abstract
A high repetition rate scintillator-based transverse beam profile diagnostic for laser-plasma accelerated proton beams has been designed and commissioned. The proton beam profiler uses differential filtering to provide coarse energy resolution and a flexible design to allow optimisation for expected beam energy range and trade-off between spatial and energy resolution depending on the application. A plastic scintillator detector, imaged with a standard 12-bit scientific camera, allows data to be taken at a high repetition rate. An algorithm encompassing the scintillator non-linearity is described to estimate the proton spectrum at different spatial locations.
- Published
- 2017
33. Operational transconductance amplifier and state machine for photonics control system for tunable filter
- Author
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Francisco X. K. Ogura, Diego Deotti, and Roberto R. Panepucci
- Subjects
business.industry ,Computer science ,Transconductance ,Amplifier ,Photonic integrated circuit ,Electrical engineering ,Hardware_PERFORMANCEANDRELIABILITY ,Analog multiplier ,Operational transconductance amplifier ,Hardware_INTEGRATEDCIRCUITS ,Photonics ,business ,Direct-coupled amplifier ,Electronic circuit - Abstract
Photonic integrated circuits suffer from silicon microring's high thermal susceptibility, and therefore a heater based control is necessary. Towards an on-chip control circuit development, we report the design of two basic devices such as a MOS Operational Transconductance Operational (OTA) amplifier and a Finite State Machine (FSM). The devices were designed and manufactured in XFAB's 0.6 μm technology (XC-06M3), all Analog and Analog-Mixed Signal circuits were developed on a Cadence environment using Virtuoso compiler tools and libraries.
- Published
- 2017
34. Latest achivements at the J-KAREN-P laser facility at QST
- Author
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H. Kiriyama, M. Nishiuchi, A. S. Pirozhkov, Y. Fukuda, H. Sakaki, A. Sagisaka, N. P. Dover, K. Kondo, K. Ogura, M. Mori, Y. Miyasaka, J. Koga, T. Zh. Esirkepov, Y. Hayashi, H. Kotaki, K. Huang, N. Nakanii, S. V. Bulanov, and M. Kando
- Subjects
Wavefront ,Physics ,Preamplifier ,business.industry ,Parabolic reflector ,02 engineering and technology ,Laser ,01 natural sciences ,law.invention ,Nonlinear system ,020210 optoelectronics & photonics ,Optics ,law ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Sapphire ,Temporal contrast ,010306 general physics ,business ,Parametric statistics - Abstract
We report on a high-contrast, high-intensity Ti:sapphire chirped-pulse amplification system that incorporates a nonlinear preamplifier based on optical parametric chirped-pulse amplification (OPCPA). Chirped-pulses are amplified to 63 J at 0.1 Hz and compressed down to 30 fs. The temporal contrast is better than 3 × 10−12 on the sub-nanosecond timescale. A peak intensity of W/cm2 on target is reached by focusing a wavefront corrected 0.3 PW laser beam with an f/1.3 off-axis parabolic mirror.
- Published
- 2017
35. The effect of laser contrast on generation of highly charged Fe ions by ultra-intense femtosecond laser pulses
- Author
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Alexander Andreev, T. Miyahara, Anatoly Ya. Faenov, Kotaro Kondo, Tatiana Pikuz, Alexander S. Pirozhkov, Mamiko Nishiuchi, M. A. Alkhimova, S. A. Pikuz, Masaki Kando, Yukinobu Watanabe, K. Nishitani, Hironao Sakaki, K. Ogura, A. Sagisaka, Nicholas P. Dover, Yuji Fukuda, Hiromitsu Kiriyama, Igor Yu. Skobelev, Ruosuke Kodama, and Kiminori Kondo
- Subjects
01.03. Fizikai tudományok ,Quantum optics ,Materials science ,Physics and Astronomy (miscellaneous) ,General Engineering ,Physics::Optics ,General Physics and Astronomy ,Plasma ,Laser ,01 natural sciences ,010305 fluids & plasmas ,Pulse (physics) ,law.invention ,Ion ,law ,Ionization ,0103 physical sciences ,Femtosecond ,Electron temperature ,Atomic physics ,010306 general physics - Abstract
Experimental studies on the formation of highly charged ions of medium-Z elements using femtosecond laser pulses with different contrast levels were carried out. Multiply charged Fe ions were generated by laser pulses with 35 fs duration and an intensity exceeding 1021 W/cm2. Using high-resolution X-ray spectroscopic methods, bulk electron temperature of the generated plasma has been identified. It is shown that the presence of a laser pre-pulse at a contrast level of 105–106 with respect to the main pulse drastically decreases the degree of Fe ionization. We conclude that an effective source of energetic, multiply charged moderate and high-Z ions based on femtosecond laser–plasma interactions can be created only using laser pulses of ultra-high contrast.
- Published
- 2017
36. 1022W/cm2, 0.1 Hz J-KAREN-P laser facility at QST
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H. Kiriyama, M. Nishiuchi, A. S. Pirozhkov, Y. Fukuda, H. Sakaki, A Sagisaka, N. Dover, K. Kondo, K. Nishitani, K. Ogura, M. Mori, Y. Miyasaka, J. Koga, T. Zh. Esirkepov, Y. Hayashi, H. Kotaki, K. Huang, N. Nakanii, S. V. Bulanov, and M. Kando
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Physics ,Parabolic reflector ,business.industry ,02 engineering and technology ,Laser ,01 natural sciences ,law.invention ,020210 optoelectronics & photonics ,Optics ,law ,0103 physical sciences ,Peak intensity ,0202 electrical engineering, electronic engineering, information engineering ,010306 general physics ,business ,Laser beams - Abstract
Broadband-pulses are amplified to 63 J and compressed to 30 fs. A peak intensity of 1022 W/cm2 by focusing a 0.3 PW laser beam with an f/1.4 off-axis parabolic mirror is achievable on target.
- Published
- 2017
37. Ultra-bright x-ray source generation from thin Al and Fe solid foils irradiated with 200 tw fs laser pulses
- Author
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M. A. Alkhimova, A. Ya. Faenov, T. A. Pikuz, I. Yu. Skobelev, S. A. Pikuz, M. Nishiuchi, H. Sakaki, A. S. Pirozhkov, A. Sagisaka, N. P. Dover, Ko. Kondo, K. Ogura, Y. Fukuda, H. Kiriyama, T. Esirkepov, S. V. Bulanov, A. Andreev, M. Kando, A. Zhidkov, K. Nishitani, T. Miyahara, Y. Watanabe, R. Kodama, and K. Kondo
- Published
- 2017
- Full Text
- View/download PDF
38. 96P Prevalence of hypothyroidism among breast cancer patients treated with radiation to the supraclavicular field: A single center survey
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H. Kato, T. Imagunbai, K. Hashimoto, E. Hohokabe, K. Ogura, S. Takebe, Y. Kosaka, K. Ueki, Yuichiro Kikawa, and Masaki Kokubo
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Oncology ,medicine.medical_specialty ,Breast cancer ,Field (physics) ,business.industry ,Internal medicine ,Medicine ,Radiology ,Hematology ,business ,Single Center ,medicine.disease - Published
- 2016
39. Burst intensification by singularity emitting radiation in multi-stream flows
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Yoshiaki Kato, K. Ogura, Noboru Hasegawa, E. N. Ragozin, Masaharu Nishikino, David Neely, Alexander S. Pirozhkov, Tatiana Pikuz, Kiminori Kondo, Masaki Kando, T. Zh. Esirkepov, Sergei V. Bulanov, Hiroyuki Daido, A. Sagisaka, Yuji Fukuda, Takashi Imazono, Tetsuya Kawachi, James Koga, Paul R. Bolton, Yukio Hayashi, Hideyuki Kotaki, A. Ya. Faenov, and Hiromitsu Kiriyama
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Shock wave ,Physics ,Multidisciplinary ,Gravitational wave ,Astrophysics::High Energy Astrophysical Phenomena ,lcsh:R ,FOS: Physical sciences ,lcsh:Medicine ,Radiation ,01 natural sciences ,Article ,Physics - Plasma Physics ,010305 fluids & plasmas ,Computational physics ,Plasma Physics (physics.plasm-ph) ,Wavelength ,Singularity ,Relativistic plasma ,0103 physical sciences ,lcsh:Q ,Gravitational singularity ,lcsh:Science ,010306 general physics ,QC ,Relativistic speed - Abstract
In various media the elementary components can emit traveling waves such as electromagnetic, gravitational or acoustic types. If these elementary emitters are synchronized, the resulting emission is coherent. Moreover, the faster the emitters approach an observer, the more intense and directional their apparent emission is, with associated frequency increase. Multi-stream flows ubiquitously occur in media (such as with shock waves and jets in astrophysical and laboratory plasmas) and produce fast moving density singularities, where high concentration and synchronism can bring constructive interference. However, a singularity emitting such characteristic coherent radiation has not been demonstrated yet. We show this general phenomenon in laser-driven relativistic plasma, which is an ideal medium for realizing these effects in the laboratory under controllable conditions. Our experiments and simulations reveal bright coherent soft x-ray radiation from nanoscale electron density singularities in multi-stream plasma. They constitute a new compact x-ray source of ultrashort duration, demanded in numerous applications. In general, singularities can be bright sources of other types of traveling waves. Thus our findings open new opportunities in different fields of science. For example, gravitational wave generation, as proposed in ultrahigh-energy accelerators, can be significantly enhanced by intentionally induced density singularities in the particle bunches. Further, we anticipate that multi-stream flows in cosmic media can produce intense bursts of coherent electromagnetic and/or gravitational waves, especially at longer wavelengths which facilitate constructive interference. We can then expect to observe more directional short wavelength bursts from cosmic emitters approaching at relativistic speeds. Thus, we present a new framework for interpreting a broad range of experimental results.
- Published
- 2016
40. New approach for improving the safety of oral immunotherapy for food allergy
- Author
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Yasuto Kondo, Atsuo Urisu, Chisato Inuo, Hitoshi Ando, Satoko Suzuki, Kenichi Tanaka, Yoichi Nakajima, Noriko Hirata, K. Yamada, Ikuya Tsuge, Norihiko Naruse, M. Kimura, and K. Ogura
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Allergy ,medicine.medical_specialty ,Oral immunotherapy ,business.industry ,medicine.medical_treatment ,digestive, oral, and skin physiology ,Immunology ,Hypoallergenic ,Immunotherapy ,medicine.disease ,Clinical Practice ,Food allergy ,Immunology and Allergy ,Medicine ,Sublingual immunotherapy ,business ,Intensive care medicine - Abstract
Summary Avoidance of causative foods is the mainstay of therapy for food allergy. This therapy places a burden, to a greater or lesser extent, on food-allergic patients and their parents if they are children. They always face the probable risk of an unexpected accident resulting from intake of a causative food. Allergen-specific immunotherapy for pollinosis and bee-venom allergy has been proven efficient and common in clinical practice. Recently, reports on oral immunotherapy (OIT) for food allergy have been increasing, and OIT has drawn attention as a therapy with the possibility of providing a cure for food allergy. Initially, we review the present status of oral antigen-specific immunotherapy for food allergy. Overall, OIT for food allergy is promising with regard to an increase in tolerance to causative foods. However, several concerns regarding safety remain. Subsequently, we review new approaches for improving the safety of OIT, including sublingual immunotherapy and modified antigens for OIT. We briefly summarize our study on OIT using heated and ovomucoid-reduced egg white as an example of a hypoallergenic antigen for safer OIT.
- Published
- 2012
41. Response to Air Insufflation in Patients with Non-Erosive Gastro-Oesophageal Reflux Disease (NERD)
- Author
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K Ogura, T Suzuki, Y Suyama, S Nishimura, and F Kira
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Male ,Insufflation ,medicine.medical_specialty ,Nerd ,Rabeprazole ,Biochemistry ,Gastroenterology ,2-Pyridinylmethylsulfinylbenzimidazoles ,Internal medicine ,Gastroscopy ,Pressure ,Humans ,Medicine ,In patient ,medicine.diagnostic_test ,business.industry ,Gastric distension ,Biochemistry (medical) ,Reflux ,Cell Biology ,General Medicine ,Hydrogen-Ion Concentration ,Middle Aged ,Anti-Ulcer Agents ,Endoscopy ,Case-Control Studies ,Gastroesophageal Reflux ,Female ,medicine.symptom ,Air insufflation ,business ,medicine.drug - Abstract
This study compared changes in intragastric pressure (IGP) in response to a gastric distension stimulus caused by air insufflation in 25 patients with non-erosive gastro-oesophageal reflux disease (NERD) and 34 healthy volunteers (controls). In four NERD patients, IGP responses were also measured before and after oral treatment with 10 mg rabeprazole daily for 2 weeks. The rate of increase in IGP at the start of insufflation was significantly higher in NERD patients than in controls. The time to appearance of symptoms (i.e. time to threshold) was significantly shorter in NERD patients than in controls. Direct measurement of IGP showed that visceral hypersensitivity and impaired fundal relaxation are both characteristic of NERD. Administration of rabeprazole led to a marked prolonging of time to threshold, indicating that treatment could alleviate this hypersensitivity.
- Published
- 2011
42. A crossed photon–atom beam method for absolute measurement of total photoionization cross sections on isolated metal atoms: Measurements on Ba and Eu atoms
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T Osawa, R. Kobayashi, Tetsuo Nagata, T. Shibata, S. Obara, K. Ogura, Yoshiro Azuma, Yuko Tohyama, S Yagi, and G. Kutluk
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Crystal ,Nuclear and High Energy Physics ,Chemistry ,Ionization ,Giant resonance ,Atom ,Bremsstrahlung ,Photoionization ,Atomic physics ,Instrumentation ,Resonance (particle physics) ,Beam (structure) - Abstract
A crossed photon-atom beam apparatus has been constructed for absolute measurement of total photoionization cross sections of isolated and neutral metallic atoms. The main purpose is to establish the technique which can be used as widely as possible for the metallic elements. Using this apparatus, measurements on Ba and Eu atoms have been made at selected energies in their 4d giant resonance regions 110–140 eV and 140–180 eV, respectively. A monochromatized synchrotron radiation was used as a light source. The target-atom density in the interaction section was determined with accuracy of 9% using the accumulation rate of metallic atoms on a quartz crystal sensor and the average velocity of the atoms obtained by a time-of-flight method combined with a pulsed electron gun. The number of photons was determined with use of a double-ion chamber preferably. The entire systematic errors have been estimated to be 20% for Ba and 27% for Eu. The comparison of the measured cross-section values with previous experimental and theoretical results is reasonable, indicating that the crossed photon–atom beam method is fairly promising technique.
- Published
- 2011
43. Peripheral tolerance and lymphocyte anergy (PP-072)
- Author
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A. Okochi, X. Shen, E. Kekalainen, K. Tsuji-Takayama, J. Huang, S. Liao, A. Hoerauf, C. Chung, E. Weiss Lavi, Y. Xu, Anna Salvetti, P. Kuo, S. Zheng, Y. Gu, T. P. Arstila, I. Wu, I. Sagiv, M. Takeuchi, K. Pokorna, J. Hoch, T. Ito, X. Zhang, M. Kuo, T. Yoshida, S. M. Anderton, A. Miettinen, C. Chan, Emilie Franck, Q. Wang, G. Ding, K. Saeki, L. H. Rossi, J. Holmgren, W. Jin, S. Hachimura, Y. Reiter, M. Ohtsuji, S. Nakamura, Y. Kodera, F. Liu, Won O. Song, L. Layland, D. Chen, T. Adjobimey, K. Ogura, M. Lehto, T. Fujii, M. Yamamoto, Olivier Boyer, Q. Xue, H. Nishimura, A. Sayi, Sahil Adriouch, R. Wolchinsky, K. Zhong, S. Ikegami, L. Xiao, I. Katayama, M. Hattori, J. Suen, S. Hirose, B. Chiang, V. Holan, C. Nishigori, C. Czerkinsky, A. Levitzki, F. Yamasaki, C. Dong, M. Shimizu, G. Lozano, K. Oved, H. Azukizawa, I. Ulmanen, T. Sashihara, J. Prochazkova, M. Zhang, K. Taguchi, A. Mueller, T. Hanafusa, M. Krulova, S. Anderton, T. Shirai, M. Totsuka, T. Hurtado de Mendoza, R. C. Rickert, J. Sun, M. Leech, K. Yamada, K. Arndts, S. Sun, T. Otani, X. Shi, M. D. Leech, A. Zajicova, M. Kibata, A. Fukunaga, K. Chu, H. Fu, R. C. Knox, N. Pöntynen, J. Satoguina, A. Yoshida, J. Oldenburg, R. Nurieva, M. Obata, E. Smeds, Y. Adachi, C. Sweenie, and R. Fujiwara
- Subjects
business.industry ,Immunology ,Immunology and Allergy ,Medicine ,Peripheral tolerance ,General Medicine ,business ,Lymphocyte anergy - Published
- 2010
44. Laser Requirements for High-Order Harmonic Generation by Relativistic Plasma Singularities
- Author
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James K. Koga, Sergei V. Bulanov, Noboru Hasegawa, K. Ogura, David Neely, Hideyuki Kotaki, Eugene N. Ragozin, Alexander S. Pirozhkov, Yoshiaki Kato, Tetsuya Kawachi, Tatiana Pikuz, Masaki Kando, Hiroyuki Daido, Takashi Imazono, Yuji Fukuda, Timur Zh. Esirkepov, Masaharu Nishikino, Anatoly Ya. Faenov, A. Sagisaka, Kiminori Kondo, Yukio Hayashi, and Hiromitsu Kiriyama
- Subjects
Diffraction ,Nuclear and High Energy Physics ,Technology ,01 natural sciences ,law.invention ,010309 optics ,Root mean square ,Optics ,Relativistic plasma ,law ,0103 physical sciences ,coherent X-ray generation ,Chirp ,High harmonic generation ,burst intensification by singularity-emitting radiation ,010306 general physics ,Adaptive optics ,Physics ,business.industry ,Laser ,Atomic and Molecular Physics, and Optics ,TK1-9971 ,high-power femtosecond lasers ,relativistic laser plasma ,Harmonics ,high-power laser quality ,relativistic plasma singularities ,Electrical engineering. Electronics. Nuclear engineering ,business - Abstract
We discuss requirements on relativistic-irradiance (I0 > 1018 W/cm2) high-power (multi-terawatt) ultrashort (femtosecond) lasers for efficient generation of high-order harmonics in gas jet targets in a new regime discovered recently (Pirozhkov et al., 2012). Here, we present the results of several experimental campaigns performed with different irradiances, analyse the obtained results and derive the required laser parameters. In particular, we found that the root mean square (RMS) wavefront error should be smaller than ~100 nm (~λ/8). Further, the angular dispersion should be kept considerably smaller than the diffraction divergence, i.e., μrad level for 100–300-mm beam diameters. The corresponding angular chirp should not exceed 10−2 μrad/nm for a 40-nm bandwidth. We show the status of the J-KAREN-P laser (Kiriyama et al., 2015; Pirozhkov et al., 2017) and report on the progress towards satisfying these requirements.
- Published
- 2018
45. Membrane-media active collaboration (M-MAC): an alternative for solid-liquid separation in drinking water treatment
- Author
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T. Sasaki, M. Itoh, Yoshimasa Watanabe, T. Hanamoto, M. Fujiwara, M. Oya, and K. Ogura
- Subjects
Engineering ,Environmental Engineering ,Waste management ,business.industry ,Health, Toxicology and Mutagenesis ,Separation (aeronautics) ,Membrane technology ,law.invention ,Membrane ,law ,Media filter ,Filter (video) ,Water treatment ,Water quality ,business ,Filtration ,Water Science and Technology - Abstract
We have proposed "membrane-media active collaboration (M-MAC)", which is a collaboration between a membrane and media in one unit, as a new solid-liquid separation technology for drinking water treatment. Membrane filtration has a high separation capability, and media filtration provides a superior stability of finished water quality and has the economies of scale. An efficient and stable solid-liquid separation can be ensured by actively utilising the advantages of each filtration function. Hanshin's help-each-other filter (HHF), which installs submerged membranes at the centre gullet of a conventional media filter, is a prototypical configuration of M-MAC. HHF enables the chemical cleaning of a membrane as part of the periodical maintenance of the entire filter and utilises a regular discharge from the membrane as feed water for media filtration. These processes can eliminate problems peculiar to membrane technology, such as those related to chemical cleaning and recovery rate. Simulation and a preliminary experiment showed that HHF provides the same treated water quality as the conventional media filter. we expect that this technological development will lead to innovations in filtration technology and increase the number of options for better solid-liquid separation in drinking water treatment.
- Published
- 2007
46. Carcinosarcoma of the fallopian tube with disappearance of carcinoma cells by neoadjuvant chemotherapy: case study
- Author
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Y, Takemoto, T, Ota, Y, Aoki, K, Ogura, D, Ogishima, and T, Matsumoto
- Subjects
Carcinosarcoma ,Chemotherapy, Adjuvant ,Fallopian Tube Neoplasms ,Humans ,Female ,Neoadjuvant Therapy ,Aged - Abstract
The authors report a case of carcinosarcoma (CS) of the fimbria of the fallopian tube in which carcinoma cells disappeared with neoadjuvant chemotherapy (NAC). A 74-year-old woman visited the present hospital with a large pelvic mass and pleural effusion. A magnetic resonance image of the tumor was highly suggestive of ovarian carcinoma. Due to the presence of both serous.adenocarcinoma cells in pleural effusion and pulmonary thrombosis, the patient was given NAC consisting of carboplatin plus paclitaxel (TC) and anticoagulant therapy with warfarin potassium. With six courses of NAC, the pleural effusion and pulmonary thrombosis disappeared, and the tumor decreased 36.2% in greatest diameter. Maximum debulking surgery was then performed. The tumor was found to be located in the fimbria of the right fallopian tube. Hysterectomy and bilateral salpingo-oophorectomy were performed, and histologic examination revealed chondrosarcoma with the presence of necrotic epithelial cells. The necrotic areas were interspersed with papillary structures, and immunohistochemical study showed positivity for CK7 and negativity for CK20, p53, and estrogen receptor (ER), indicating serous adenocarcinoma. Thus, heterologous CS with disappearance of viable carcinoma cells by NAC was diagnosed. The patient was given adjuvant chemotherapy consisting of three courses of TC, and there has been no evidence of disease for 20 months. The authors' experience in this case of gynecologic CS indicates that a serous adenocarcinomatous component of tubal CS can be well cured by TC-based NAC.
- Published
- 2015
47. Ion Acceleration via 'Nonlinear Vacuum Heating' by the Laser Pulse Obliquely Incident on a Thin Foil Target
- Author
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Akifumi Yogo, Yuji Fukuda, Hiroaki Nishimura, Kotaro Kondo, M. Kanasaki, T. Zh. Esirkepov, Sv Bulanov, Alexander S. Pirozhkov, Paul R. Bolton, H. Sakaki, Michiaki Mori, and K. Ogura
- Subjects
Materials science ,FOS: Physical sciences ,Electron ,01 natural sciences ,010305 fluids & plasmas ,law.invention ,Ion ,High Energy Physics - Experiment ,symbols.namesake ,High Energy Physics - Experiment (hep-ex) ,law ,0103 physical sciences ,010306 general physics ,FOIL method ,Brewster's angle ,Pulse duration ,Condensed Matter Physics ,Laser ,Physics - Plasma Physics ,Pulse (physics) ,Plasma Physics (physics.plasm-ph) ,Nuclear Energy and Engineering ,Nonlinear resonance ,symbols ,Atomic physics ,Optics (physics.optics) ,Physics - Optics - Abstract
Dependence of the energy of ions accelerated during interaction of the laser pulse obliquelly incident on the thin foil target on the laser polarization is studied experimentally and theoretically. We found that the ion energy being maximal for the p-polarization gradually decreases when the pulse becomes s-polarized. The experimentally found dependences of the ion energy are explained by invoking the anomalous electron heating which results in high electrostatic potential formation at the target surface. Anomalous heating of electrons beyond the energy of quiver motion in the laser field is described within the framework of theoretical model of driven oscillator with a step-like nonlinearity. We have demonstrated that the electron anomalous heating can be realized in two regimes: nonlinear resonance and stochastic heating, depending on the extent of stochasticity. We have found the accelerated ion energy scaling determined by the laser intensity, pulse duration, polarization angle and incident angle.
- Published
- 2015
48. Growth and optical property characterizations of ZnTe:(Al,N) layers using two co‐doping techniques
- Author
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J. Ueno, K. Ogura, S. Katsuta, A. Ichiba, and Masakazu Kobayashi
- Subjects
Crystal ,Materials science ,Dopant ,Metastability ,Pl spectra ,Doping ,Optical property ,Analytical chemistry ,Polar ,Nanotechnology ,Condensed Matter Physics ,Molecular beam epitaxy - Abstract
In order to get around the high and activated n-doping levels for ZnTe, the co-doping technique known as effective method to overcome the dopant compensation was explored. The co-doping concept is to introduce two oppositely polar atoms at the same time in a 2:1 ratio, forming metastable three-atom complexes located at adjacent crystal sites. In this study, two types of deposition process were considered to place the co-dopants at the intended site, and the co-doped ZnTe:(Al, N) layers were grown on (001) oriented ZnTe substrates by molecular beam epitaxy. From the low temperature PL spectra, the increase of Al activation was confirmed by using co-doping sequences, and the activation of N dopant was also confirmed for one doping sequence even thought the doping level was maintained the same. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
- Published
- 2006
49. MBE growth of ZnSe/MgCdS and ZnCdS/MgCdS superlattices for UV‐A sensors
- Author
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Koji Onomitsu, Masakazu Kobayashi, Yoshiji Horikoshi, A. Ichiba, J. Ueno, S. Katsuta, and K. Ogura
- Subjects
Crystal ,Photoluminescence ,Materials science ,business.industry ,Superlattice ,Optoelectronics ,Photodetector ,Condensed Matter Physics ,business ,Luminescence ,Layer (electronics) ,Visible spectrum ,Molecular beam epitaxy - Abstract
ZnSe/MgCdS and ZnCdS/MgCdS superlattices were grown on semi insulating (001) oriented GaAs substrates by molecular beam epitaxy (MBE). The crystal quality and optical properties were examined for both superlattices. The observed photoluminescence (PL) peak intensity of ZnCdS/MgCdS was much stronger than that of ZnSe/MgCdS while ZnSe/MgCdS showed sharper luminescence line width. The PL peak energy position was compared with the theoretical value derived from the Kronig-Penny model. The degradation of crystal quality was observed by increasing Mg content in MgCdS layer and drastic PL property degradation was observed when the Mg content in the layer exceeded a certain value. Two superlattices were applied to the UV-A sensor of the metal-semiconductor-metal (MSM) configuration. Both photodetectors exhibited a high sensitivity in the UV-A region with a sharp cut-off in the visible wavelength region; the ON-OFF ratio of sensor was about 103 for both structures. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
- Published
- 2006
50. Progress in potential formation and findings in the associated radially sheared electric-field effects on suppressing intermittent turbulent vortex-like fluctuations and reducing transverse losses
- Author
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T Cho, J Kohagura, M Hirata, T Numakura, H Higaki, H Hojo, M Ichimura, K Ishii, K.Md Islam, A Itakura, I Katanuma, Y Nakashima, T Saito, Y Tatematsu, M Yoshikawa, Y Takemura, A Kojima, T Kobayashi, Y Yamaguchi, Y Miyata, N Yokoyama, Y Tomii, Y Miyake, S Kiminami, K Shimizu, Y Kubota, H Saimaru, Y Higashizono, A Mase, Y Yasaka, K Ogura, K Sakamoto, M Yoshida, V.P Pastukhov, T Imai, S Miyoshi, and GAMMA 10 Group
- Subjects
Shear (sheet metal) ,Physics ,Nuclear and High Energy Physics ,Turbulence ,Electric field ,Magnetic confinement fusion ,Plasma diagnostics ,Plasma ,Mechanics ,Atomic physics ,Fusion power ,Condensed Matter Physics ,Vortex - Abstract
Following the 19th IAEA Fusion Energy Conference (Lyon, 2002), (1) three-time progress in the formation of ion-confining potential heights c including a record of 2.1 kV in comparison to those attained 1992–2002 is achieved for tandem-mirror plasmas in the hot-ion mode with ion temperatures of several kiloelectronvolts. (2) The advance in the potential formation gives the bases for finding the remarkable effects of radially produced shear of electric fields Er, or non-uniform sheared plasma rotation on the suppression of intermittent vortex-like turbulent fluctuations. (i) Such a shear effect is visually highlighted by x-ray tomography diagnostics; that is, spatially and temporally intermittent vortex-like fluctuated structures are clearly observed as two-dimensionally reconstructed visual structures for the first time in kiloelectronvolt order ion-cyclotron heated plasmas having a weak shear in GAMMA 10. (ii) However, during the application of plug electron-cyclotron heatings (ECH), the associated potential rise produces a stronger shear (dEr/dr = several 10 kV m−2) resulting in the disappearance of such intermittent turbulent vortices with plasma confinement improvement. X-ray observations also show elongation of a vortex structure from a circular into an ellipsoidal shape, as depicted in H-mode theories, with an outward shift. (3) For the physics interpretations and control of such potential and the associated shear formation, the validity of our proposed theory of the potential formation is extensionally tested under the conditions with auxiliary heating. The data described above fit well to the extended surfaces calculated from our proposed consolidated theory of the strong ECH theory (plateau formation) with Pastukhov's theory on energy confinement.
- Published
- 2005
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