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Hasegawa H, Nakashima H, Matsui T, Ohta M. Helical Geometry Effect on Tritium Breeding in Heliotron Fusion Reactor Blanket. NUCL SCI ENG 2017. [DOI: 10.13182/nse84-a18642] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Koami H, Sakamoto Y, Yamada KC, Matsuda T, Nishi J, Nakayama K, Sakurai R, Ohta M, Imahase H, Yahata M, Umeka M, Miike T, Nagashima F, Iwamura T, Inoue S. What factor within the Japanese Association for Acute Medicine (JAAM) disseminated intravascular coagulation (DIC) criteria is most strongly correlated with trauma induced DIC? A retrospective study using thromboelastometry in a single center in Japan. Eur J Trauma Emerg Surg 2017; 43:431-438. [PMID: 28093623 PMCID: PMC5533846 DOI: 10.1007/s00068-016-0756-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Accepted: 12/23/2016] [Indexed: 11/26/2022]
Abstract
Purpose The diagnostic criteria for disseminated intravascular coagulation (DIC) established by the Japanese Association for Acute Medicine (JAAM) is able to diagnose DIC accurately and promptly. The aim of this retrospective study is to evaluate the degree of association between each parameter of JAAM DIC criteria and the diagnosis of trauma induced DIC (T-DIC) utilizing thromboelastometry (ROTEM). Methods Trauma patients transported to our hospital with ROTEM performed in the emergency department between January 2013 and December 2015 were enrolled in this study. We evaluated (1) the characteristics of T-DIC, (2) the relationships between T-DIC and each parameter of the JAAM DIC criteria and (3) the diagnostic accuracies of each parameter for T-DIC by statistical measurement. Results All 72 patients (21 T-DIC and 51 control) were included in primary analysis. T-DIC was significantly related to younger age, more severe trauma scores, more cases of massive transfusions, and remarkable coagulation abnormality detected by standard coagulation tests. In the cases of T-DIC, ROTEM showed longer clotting time, lower acceleration, lower clot firmness, and inhibited fibrinolysis in EXTEM/INTEM. Within the JAAM DIC score, PT-INR ≥1.2 was the most accurate factor for T-DIC diagnosis; sensitivity 60.0%, specificity 100.0%, and accuracy 88.7%. PT-INR ≥1.2 was statistically correlated with the JAAM DIC score (p < 0.001, r = 0.709). The univariate analysis based on 1.2 of PT-INR indicated statistical differences in most categories of ROTEM, which is similar to analysis performed for the presence and absence of T-DIC. Conclusions Among JAAM DIC criteria, the PT-INR ≥1.2 was the most accurate factor for both the diagnosis of T-DIC and the evaluation of its severity.
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Ohta M, Midorikawa T, Hikihara Y, Masuo Y, Sakamoto S, Torii S, Kawakami Y, Fukunaga T, Kanehisa H. Validity of segmental bioelectrical impedance analysis for estimating fat-free mass in children including overweight individuals. Appl Physiol Nutr Metab 2016; 42:157-165. [PMID: 28112969 DOI: 10.1139/apnm-2016-0137] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study examined the validity of segmental bioelectrical impedance (BI) analysis for predicting the fat-free masses (FFMs) of whole-body and body segments in children including overweight individuals. The FFM and impedance (Z) values of arms, trunk, legs, and whole body were determined using a dual-energy X-ray absorptiometry and segmental BI analyses, respectively, in 149 boys and girls aged 6 to 12 years, who were divided into model-development (n = 74), cross-validation (n = 35), and overweight (n = 40) groups. Simple regression analysis was applied to (length)2/Z (BI index) for each of the whole-body and 3 segments to develop the prediction equations of the measured FFM of the related body part. In the model-development group, the BI index of each of the 3 segments and whole body was significantly correlated to the measured FFM (R2 = 0.867-0.932, standard error of estimation = 0.18-1.44 kg (5.9%-8.7%)). There was no significant difference between the measured and predicted FFM values without systematic error. The application of each equation derived in the model-development group to the cross-validation and overweight groups did not produce significant differences between the measured and predicted FFM values and systematic errors, with an exception that the arm FFM in the overweight group was overestimated. Segmental bioelectrical impedance analysis is useful for predicting the FFM of each of whole-body and body segments in children including overweight individuals, although the application for estimating arm FFM in overweight individuals requires a certain modification.
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Kaneko Y, Kondo H, Ohta M, Takeuchi T. FRI0104 Long-Term Followup of Biologic Agents in Patients with Rheumatoid Arthritis. Ann Rheum Dis 2016. [DOI: 10.1136/annrheumdis-2016-eular.3339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Midorikawa T, Tanaka S, Ando T, Tanaka C, Masayuki K, Ohta M, Torii S, Sakamoto S. Is There a Chronic Elevation in Organ-Tissue Sleeping Metabolic Rate in Very Fit Runners? Nutrients 2016. [PMCID: PMC4848665 DOI: 10.3390/nu8040196] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
It is unclear whether the resting metabolic rate of individual organ-tissue in adults with high aerobic fitness is higher than that in untrained adults; in fact, this topic has been debated for years using a two-component model. To address this issue, in the present study, we examined the relationship between the measured sleeping energy expenditure (EE) by using an indirect human calorimeter (IHC) and the calculated resting EE (REE) from organ-tissue mass using magnetic resonance imaging, along with the assumed metabolic rate constants in healthy adults. Seventeen healthy male long-distance runners were recruited and grouped according to the median V·O2peak: very fit group (>60 mL/min/kg; n = 8) and fit group (<60 mL/min/kg; n = 9). Participants performed a graded exercise test for determining V·O2peak; X-ray absorptiometry and magnetic resonance imaging were used to determine organ-tissue mass, and IHC was used to determine sleeping EE. The calculated REE was estimated as the sum of individual organ-tissue masses multiplied by their metabolic rate constants. No significant difference was observed in the measured sleeping EE, calculated REE, and their difference, as well as in the slopes and intercepts of the two regression lines between the groups. Moreover, no significant correlation between V·O2peak and the difference in measured sleeping EE and calculated REE was observed for all subjects. Thus, aerobic endurance training does not result in a chronic elevation in the organ-tissue metabolic rate in cases with V·O2peak of approximately 60 mL/min/kg.
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Wakuno A, Aoki M, Kushiro A, Mae N, Kodaira K, Maeda T, Yamazaki Y, Ohta M. Comparison of alfaxalone, ketamine and thiopental for anaesthetic induction and recovery in Thoroughbred horses premedicated with medetomidine and midazolam. Equine Vet J 2016; 49:94-98. [PMID: 26850885 DOI: 10.1111/evj.12548] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2015] [Accepted: 11/25/2015] [Indexed: 11/28/2022]
Abstract
REASONS FOR PERFORMING STUDY There is limited information on clinical use of the new injectable anaesthetic agent alfaxalone in Thoroughbred horses. OBJECTIVES To compare anaesthetic induction and recovery characteristics and cardiopulmonary responses between alfaxalone, ketamine and thiopental in Thoroughbred horses premedicated with medetomidine and midazolam. STUDY DESIGN Randomised blinded experimental cross-over study. METHODS Six Thoroughbred horses were anaesthetised 3 times with alfaxalone 1 mg/kg bwt, ketamine 2.5 mg/kg bwt or thiopental 4 mg/kg bwt after premedication with medetomidine 6 μg/kg bwt and midazolam 20 μg/kg bwt. Qualities of anaesthetic induction and recovery were scored on a scale of 1 (poor) to 5 (excellent). Induction time and recovery time were recorded. Cardiopulmonary values (heart rate, respiratory rate, arterial blood pressures, and arterial blood gases) were recorded throughout anaesthesia. Data were analysed with nonparametric methods. RESULTS The anaesthetic induction (P = 0.2) and recovery (P = 0.1) quality scores (median, range) were not different amongst protocols and were 4.0, 3-5; 5.0, 4-5; 4.5, 3-5; and 4.5, 3-5; 3.5, 2-5; 4.0, 2-5 for alfaxalone, ketamine and thiopental, respectively. Induction time for ketamine (67, 53-89 s) was significantly longer than that for alfaxalone (49, 40-51 s, P = 0.01) and thiopental (48, 43-50 s, P = 0.01). Time to standing for alfaxalone (44, 40-63 min, P = 0.01) and thiopental (39, 30-58 min, P = 0.01) was significantly longer than that for ketamine (25, 18-26 min). Cardiovascular values were maintained within the clinically acceptable level throughout anaesthesia. Respiratory rate significantly decreased during anaesthesia for all 3 drugs; however, spontaneous breathing did not disappear, and PaCO2 values were maintained at approximately 50 mmHg. CONCLUSIONS All 3 drugs showed similar effects in relation to anaesthetic induction and recovery qualities and cardiopulmonary responses. However, alfaxalone and thiopental prolonged recovery time compared with ketamine.
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Anzai H, Yoshida Y, Sugiyama S, Endo H, Matsumoto Y, Ohta M. Porosity dependency of an optimized stent design for an intracranial aneurysm. Technol Health Care 2015; 23:547-56. [PMID: 26410116 DOI: 10.3233/thc-151007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Optimal design of stents for a cerebral aneurysm is desired for efficient flow reduction in the aneurysm. OBJECTIVE In this study, we aimed to optimize stent design at several porosities, estimate the influence of stent design on aneurysm flow, and evaluate the ability of stents to reduce flow. METHODS Stent models were constructed as sets of squares or rectangles in the necks of a two-dimensional (2D) and realistic aneurysm. Then, automated optimization was performed using a combination of simulated annealing and lattice Boltzmann flow simulation. RESULTS By simulated annealing, stents were gradually modified to reduce the average velocity in an aneurysm. As a result of optimization, stents of all porosities demonstrated an inhomogeneous distribution with dense struts in the inflow area. Flow reduction was increased compared with the initial stent. Under the condition of high porosity, flow reduction by the stent drastically increased as porosity decreased. Under low porosity, the increase of velocity reduction was moderate even as porosity decreased. CONCLUSIONS Optimization can enhance flow reduction by stents. However, the increase in reduction associated with decreasing porosity is moderate under lower-porosity conditions. This threshold may help in the choice of stent porosity for each specific aneurysm.
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Kaneko Y, Kondo H, Ohta M, Takeuchi T. SAT0095 Identifying Factors Associated with Discordance Between Erythrocyte Sedimentation Rate and C-Reactive Protein in Patients with Rheumatoid Arthritis. Ann Rheum Dis 2015. [DOI: 10.1136/annrheumdis-2015-eular.4352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Goto M, Makihara H, Ohta M, Maseki S, Hasegawa Y, Nakanishi H, Kurita K. Biological significance and regulation of podoplanin expression in oral squamous cell carcinomas. J Oral Maxillofac Surg 2014. [DOI: 10.1016/j.joms.2014.06.328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Moriyama M, Furukawa S, Kawano S, Goto Y, Kiyoshima T, Tanaka A, Maehara T, Hayashida JN, Ohta M, Nakamura S. The diagnostic utility of biopsies from the submandibular and labial salivary glands in IgG4-related dacryoadenitis and sialoadenitis, so-called Mikulicz's disease. Int J Oral Maxillofac Surg 2014; 43:1276-81. [PMID: 25062551 DOI: 10.1016/j.ijom.2014.06.014] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 06/26/2014] [Accepted: 06/30/2014] [Indexed: 12/24/2022]
Abstract
IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS) is characterized by serum IgG4 elevation and the infiltration of IgG4-positive plasma cells in glandular tissues. For definitive diagnosis of IgG4-DS, biopsies of local lesions are recommended to exclude Sjögren's syndrome (SS), malignant tumours, and similar disorders. In this study, we examined the diagnostic utility of submandibular gland (SMG) and labial salivary gland (LSG) biopsies in IgG4-DS. Fourteen patients presenting with swelling of the SMG (eight females and six males) underwent both SMG and LSG biopsies. The sensitivity, specificity, and accuracy of SMG biopsies were all 100.0%. In contrast, those of LSG biopsies were 69.2%, 100.0%, and 71.4%, respectively. Thirty-three out of 61 LSG biopsies (54.1%) from all 14 patients were positive for the diagnostic criteria of IgG4-DS (IgG4-positive/IgG-positive plasma cells >0.4). None of the patients experienced complications such as facial nerve palsy, sialocele, or hyposalivation. The IgG4/IgG ratio showed no significant correlation between the LSG and SMG. The final diagnosis was IgG4-DS in 13 patients and marginal zone B-cell lymphoma (MZL) in one. These results suggest that incisional biopsy of the SMG is useful and appropriate for the definitive diagnosis of IgG4-DS, while diagnosis by LSG biopsy alone requires more caution.
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Furukawa S, Moriyama M, Kawano S, Tanaka A, Maehara T, Hayashida JN, Goto Y, Kiyoshima T, Shiratsuchi H, Ohyama Y, Ohta M, Imabayashi Y, Nakamura S. Clinical relevance of Küttner tumour and IgG4-related dacryoadenitis and sialoadenitis. Oral Dis 2014; 21:257-62. [PMID: 24844187 PMCID: PMC4359042 DOI: 10.1111/odi.12259] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Revised: 05/05/2014] [Accepted: 05/14/2014] [Indexed: 12/24/2022]
Abstract
Objectives Küttner tumour (KT), so-called chronic sclerosing sialoadenitis, is characterised by concomitant swelling of the submandibular glands secondary to strong lymphocytic infiltration and fibrosis independent of sialolith formation. However, recent studies have indicated that some patients with KT develop high serum levels of IgG4 and infiltration of IgG4-positive plasma cells, namely IgG4-related dacryoadenitis and sialoadenitis (IgG4-DS), so-called Mikulicz's disease. The aim of this study was to clarify the clinical and pathological associations between KT and IgG4-DS. Materials and Methods Fifty-four patients pathologically diagnosed with KT or chronic sialoadenitis were divided into two groups according to the presence or absence of sialolith (KT-S (+) or KT-S (−), respectively). Results There were no significant differences in the clinical findings, including the mean age, sex and disease duration, between the two groups. All patients in the KT-S (+) group showed unilateral swelling without infiltration of IgG4-positive plasma cells or a history of other IgG4-related diseases (IgG4-RD), while those in the KT-S (−) group showed bilateral swelling (37.5%), strong infiltration of IgG4-positive plasma cells (87.5%) and a history of other IgG4-RD (12.5%). Conclusions These results suggest an association between the pathogeneses of KT-S (−) and IgG4-DS, but not KT-S (+).
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Ohta M, Nakamura K, Kubo T, Suzuki T. Detoxification Effect of Iron-encaging Zeolite-processed Water in Tributyltin-intoxicated Euglena gracilis Z. Biosci Biotechnol Biochem 2014; 65:14-21. [PMID: 11272817 DOI: 10.1271/bbb.65.14] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In our previous paper, we reported the restoration promoting effects of mineral-encaging zeolite-processed water, especially of a Fe-encaging one, on tributyltin chloride (TBTCl)-intoxicated Euglena gracilis. This present study extends the investigation on the behavior of TBTCl and a xenobiotic enzyme, cytochrome P-450, in Euglena cells incubated with or without Fe-encaging zeolite-processed water (FeZW). Subcellular fractionation of TBTCl-intoxicated Euglena cells, atomic absorption spectrophotometry, and GC analyses showed that TBTCl was rapidly incorporated into the cells to halt cell motility. GC-MS showed that FeZW promoted conversion of TBTCl to dibutyltin (DBT) as the major metabolite in the microsomal fraction of the cells. An in vitro incubation system with heat-treated microsomes did not convert TBTCl to DBT. The contribution of cytochrome P-450 in the microsomal fraction was suggested by an immunochemical method. The results suggest that the improvement of detoxification by FeZW in the TBT-intoxicated Euglena cells should be due to activation of biotransformation system of the Euglena cells by FeZW.
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Ohyama K, Moriyama M, Hayashida JN, Tanaka A, Maehara T, Ieda S, Furukawa S, Ohta M, Imabayashi Y, Nakamura S. Saliva as a potential tool for diagnosis of dry mouth including Sjögren's syndrome. Oral Dis 2014; 21:224-31. [DOI: 10.1111/odi.12252] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 04/10/2014] [Accepted: 04/15/2014] [Indexed: 01/29/2023]
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Yahata M, Sakamoto Y, Inoue S, Iwamura T, Fujita R, Koami H, Miike T, Imahase H, Narumi S, Goto A, Ohta M. More effective use of polymyxin-B hemoperfusion for nonoperation cases. Crit Care 2014. [PMCID: PMC4273848 DOI: 10.1186/cc14035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Yamamoto T, Shibata T, Ohta M, Yasumoto M, Nishida K, Hatayama A, Mattei S, Lettry J, Sawada K, Fantz U. Modeling of neutrals in the Linac4 H(-) ion source plasma: hydrogen atom production density profile and Hα intensity by collisional radiative model. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B118. [PMID: 24593558 DOI: 10.1063/1.4833016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To control the H(0) atom production profile in the H(-) ion sources is one of the important issues for the efficient and uniform surface H(-) production. The purpose of this study is to construct a collisional radiative (CR) model to calculate the effective production rate of H(0) atoms from H2 molecules in the model geometry of the radio-frequency (RF) H(-) ion source for Linac4 accelerator. In order to validate the CR model by comparison with the experimental results from the optical emission spectroscopy, it is also necessary for the model to calculate Balmer photon emission rate in the source. As a basic test of the model, the time evolutions of H(0) production and the Balmer Hα photon emission rate are calculated for given electron energy distribution functions in the Linac4 RF H(-) ion source. Reasonable test results are obtained and basis for the detailed comparisons with experimental results have been established.
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Ohta M, Mattei S, Yasumoto M, Hatayama A, Lettry J. Numerical study of the inductive plasma coupling to ramp up the plasma density for the Linac4 H(-) ion source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B113. [PMID: 24593553 DOI: 10.1063/1.4833920] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In the Linac4 H(-) ion source, the plasma is generated by an RF antenna operated at 2 MHz. In order to investigate the conditions necessary for ramping up the plasma density of the Linac4 H(-) ion source in the low plasma density, a numerical study has been performed for a wide range of parameter space of RF coil current and initial pressure from H2 gas injection. We have employed an Electromagnetic Particle in Cell model, in which the collision processes have been calculated by a Monte Carlo method. The results have shown that the range of initial gas pressure from 2 to 3 Pa is suitable for ramping up plasma density via inductive coupling.
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Nishida K, Mochizuki S, Ohta M, Yasumoto M, Lettry J, Mattei S, Hatayama A. Equivalent circuit of radio frequency-plasma with the transformer model. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B117. [PMID: 24593557 DOI: 10.1063/1.4832060] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
LINAC4 H(-) source is radio frequency (RF) driven type source. In the RF system, it is required to match the load impedance, which includes H(-) source, to that of final amplifier. We model RF plasma inside the H(-) source as circuit elements using transformer model so that characteristics of the load impedance become calculable. It has been shown that the modeling based on the transformer model works well to predict the resistance and inductance of the plasma.
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Lettry J, Aguglia D, Andersson P, Bertolo S, Butterworth A, Coutron Y, Dallocchio A, Chaudet E, Gil-Flores J, Guida R, Hansen J, Hatayama A, Koszar I, Mahner E, Mastrostefano C, Mathot S, Mattei S, Midttun Ø, Moyret P, Nisbet D, Nishida K, O'Neil M, Ohta M, Paoluzzi M, Pasquino C, Pereira H, Rochez J, Sanchez Alvarez J, Sanchez Arias J, Scrivens R, Shibata T, Steyaert D, Thaus N, Yamamoto T. Status and operation of the Linac4 ion source prototypes. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B122. [PMID: 24593562 DOI: 10.1063/1.4848975] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
CERN's Linac4 45 kV H(-) ion sources prototypes are installed at a dedicated ion source test stand and in the Linac4 tunnel. The operation of the pulsed hydrogen injection, RF sustained plasma, and pulsed high voltages are described. The first experimental results of two prototypes relying on 2 MHz RF-plasma heating are presented. The plasma is ignited via capacitive coupling, and sustained by inductive coupling. The light emitted from the plasma is collected by viewports pointing to the plasma chamber wall in the middle of the RF solenoid and to the plasma chamber axis. Preliminary measurements of optical emission spectroscopy and photometry of the plasma have been performed. The design of a cesiated ion source is presented. The volume source has produced a 45 keV H(-) beam of 16-22 mA which has successfully been used for the commissioning of the Low Energy Beam Transport (LEBT), Radio Frequency Quadrupole (RFQ) accelerator, and chopper of Linac4.
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Mattei S, Ohta M, Yasumoto M, Hatayama A, Lettry J, Grudiev A. Plasma ignition and steady state simulations of the Linac4 H(-) ion source. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B115. [PMID: 24593555 DOI: 10.1063/1.4833919] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The RF heating of the plasma in the Linac4 H(-) ion source has been simulated using a particle-in-cell Monte Carlo collision method. This model is applied to investigate the plasma formation starting from an initial low electron density of 10(12) m(-3) and its stabilization at 10(18) m(-3). The plasma discharge at low electron density is driven by the capacitive coupling with the electric field generated by the antenna, and as the electron density increases the capacitive electric field is shielded by the plasma and induction drives the plasma heating process. Plasma properties such as e(-)/ion densities and energies, sheath formation, and shielding effect are presented and provide insight to the plasma properties of the hydrogen plasma.
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Hatayama A, Shibata T, Nishioka S, Ohta M, Yasumoto M, Nishida K, Yamamoto T, Miyamoto K, Fukano A, Mizuno T. Kinetic modeling of particle dynamics in H(-) negative ion sources (invited). THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A510. [PMID: 24593433 DOI: 10.1063/1.4852300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Progress in the kinetic modeling of particle dynamics in H(-) negative ion source plasmas and their comparisons with experiments are reviewed, and discussed with some new results. Main focus is placed on the following two topics, which are important for the research and development of large negative ion sources and high power H(-) ion beams: (i) Effects of non-equilibrium features of EEDF (electron energy distribution function) on H(-) production, and (ii) extraction physics of H(-) ions and beam optics.
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Yasumoto M, Ohta M, Kawamura Y, Hatayama A. Analysis of rapid increase in the plasma density during the ramp-up phase in a radio frequency negative ion source by large-scale particle simulation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02B126. [PMID: 24593566 DOI: 10.1063/1.4858136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Numerical simulations become useful for the developing RF-ICP (Radio Frequency Inductively Coupled Plasma) negative ion sources. We are developing and parallelizing a two-dimensional three velocity electromagnetic Particle-In-Cell code. The result shows rapid increase in the electron density during the density ramp-up phase. A radial electric field due to the space charge is produced with increase in the electron density and the electron transport in the radial direction is suppressed. As a result, electrons stay for a long period in the region where the inductive electric field is strong, and this leads efficient electron acceleration and a rapid increasing of the electron density.
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Takai Y, Ohta M, Akagi R, Kato E, Wakahara T, Kawakami Y, Fukunaga T, Kanehisa H. Applicability of ultrasound muscle thickness measurements for predicting fat-free mass in elderly population. J Nutr Health Aging 2014; 18:579-85. [PMID: 24950147 DOI: 10.1007/s12603-013-0419-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
OBJECTIVE This study aimed to examine the applicability of ultrasound muscle thickness (MT) measurements for predicting whole body fat-free mass (FFM) in elderly individuals. DESIGN AND SETTING Cross-sectional study of 77 healthy elderly individuals. METHODS MTs at nine sites of the body and FFM were determined using B-mode ultrasound and dual-energy x-ray absorptiometry (DXA), respectively, in 44 women and 33 men aged 52 to 78 yrs. Stepwise multiple regression analysis produced two equations for predicting DXA-based FFM with sex (dummy: woman = 0 and man = 1) and either MTs at the anterior and posterior of thigh and lower leg (Eq1) or the product of MT and limb length (MT×LL) at thigh anterior and posterior, lower leg posterior, and upper arm anterior (Eq2) as independent variables. RESULTS The R2 and SEE for each of the two equations were 0.929 and 2.5 kg for Eq1 and 0.955 and 2.0 kg for Eq2. The estimated FFM from each of Eq1 (44.4 ± 8.9 kg) and Eq2 (44.4 ± 9.0 kg) did not significantly differ from that of the DXA-based FFM (44.4 ± 9.2 kg), without systematic error. However, the absolute value of the difference between the DXA-based and estimated FFM was significantly greater with Eq1 (2.0 ± 1.5 kg) than with Eq2 (1.5 ± 1.3 kg). CONCLUSION The current results indicate that ultrasound MT measurement is useful to predict FFM in the elderly, and its accuracy is improved by using the product of MT and limb length as an independent variable.
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Aghi M, Vogelbaum MA, Jolly DJ, Robbins JM, Ostertag D, Ibanez CE, Gruber HE, Kasahara N, Bankiewicz K, Cloughesy TF, Chang SM, Butowski N, Kesari S, Chen C, Mikkelsen T, Landolfi J, Chiocca EA, Elder JB, Foltz G, Pertschuk D, Anaizi A, Taylor C, Kosty J, Zimmer L, Theodosopoulos P, Anaizi A, Gantwerker E, Pensak M, Theodosopoulos P, Anaizi A, Grewal S, Theodosopoulos P, Zimmer L, Anaizi A, Pensak M, Theodosopoulos P, Arakawa Y, Kang Y, Murata D, Fujimoto KI, Miyamoto S, Blagia M, Paulis M, Orunesu G, Serra S, Akers J, Ramakrishnan V, Kim R, Skog J, Nakano I, Pingle S, Kalinina J, Kesari S, Breakfield X, Hochberg F, Van Meir E, Carter B, Chen C, Czech T, Nicholson J, Frappaz D, Kortmann RD, Alapetite C, Garre ML, Ricardi U, Saran F, Calaminus G, Hamer PDW, Hendriks E, Mandonnet E, Barkhof F, Zwinderman K, Duffau H, Esquenazi Y, Johnson J, Tandon N, Esquenazi Y, Friedman E, Lin Y, Zhu JJ, Tandon N, Fujimaki T, Kobayashi M, Wakiya K, Ohta M, Adachi J, Fukuoka K, Suzuki T, Yanagisawa T, Matsutani M, Mishima K, Sasaki J, Nishikawa R, Hoffermann M, Bruckmann L, Ali KM, Asslaber M, Payer F, von Campe G, Jungk C, Beigel B, Abb V, Herold-Mende C, Unterberg A, Kim JH, Cho YH, Kim CJ, Mardor Y, Nissim O, Grober Y, Guez D, Last D, Daniels D, Hoffmann C, Nass D, Talianski A, Spiegelmann R, Cohen Z, Zach L, Marupudi N, Mittal S, Michaud K, Cantin L, Cottin S, Dandurand C, Mohammadi A, Hawasli A, Rodriguez A, Schroeder J, Laxton A, Elson P, Tatter S, Barnett G, Leuthardt E, Moriuchi S, Dehara M, Fukunaga T, Hagiwara Y, Soda H, Imakita M, Nitta M, Maruyama T, Iseki H, Ikuta S, Tamura M, Chernov M, Okamoto S, Okada Y, Muragaki Y, Ohue S, Kohno S, Inoue A, Yamashita D, Kumon Y, Ohnishi T, Oppido P, Villani V, Vidiri A, Pace A, Pompili A, Carapella C, Orringer D, Lau D, Niknafs Y, Piquer J, Llacer JL, Rovira V, Riesgo P, Cremades A, Rotta R, Levine N, Prabhu S, Sawaya R, Weinberg J, Rao G, Tummala S, Tilley C, Rovin R, Kassam A, Schwartz C, Romagna A, Thon N, Tonn JC, Schwarz SB, Kreth FW, Sonoda Y, Shibahara I, Saito R, Kanamori M, Kumabe T, Tominaga T, Steele C, Lawrence J, Rovin R, Winn R, Rachinger W, Simon M, Dutzmann S, Feigl G, Kremenevskaya N, Thon N, Tonn JC, Whelan H, Kelly M, Jogel S, Kaufmann B, Foy A, Lew S, Quirk B, Yong RL, Wu T, Mihatov N, Shen MJ, Brown MA, Zaghloul KA, Park GE, Park JK. SURGICAL THERAPIES. Neuro Oncol 2013; 15:iii217-iii225. [PMCID: PMC3823906 DOI: 10.1093/neuonc/not191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2024] Open
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Takai Y, Ohta M, Akagi R, Kato E, Wakahara T, Kawakami Y, Fukunaga T, Kanehisa H. Validity of ultrasound muscle thickness measurements for predicting leg skeletal muscle mass in healthy Japanese middle-aged and older individuals. J Physiol Anthropol 2013; 32:12. [PMID: 24067065 PMCID: PMC3817997 DOI: 10.1186/1880-6805-32-12] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2013] [Accepted: 09/14/2013] [Indexed: 12/25/2022] Open
Abstract
Background The skeletal muscle mass of the lower limb plays a role in its mobility during daily life. From the perspective of physical resources, leg muscle mass dominantly decreases after the end of the fifth decade. Therefore, an accurate estimate of the muscle mass is important for the middle-aged and older population. The present study aimed to clarify the validity of ultrasound muscle thickness (MT) measurements for predicting leg skeletal muscle mass (SM) in the healthy Japanese middle-aged and older population. Findings MTs at four sites of the lower limb and the bone-free lean tissue mass (LTM) of the right leg were determined using brightness-mode ultrasonography and dual-energy X-ray absorptiometry (DXA), respectively, in 44 women and 33 men, 52- to 78-years old. LTM was used as a representative variable of leg skeletal muscle mass. In the model-development group (30 women and 22 men), regression analysis produced an equation with R2 and standard error of the estimate (SEE) of 0.958 and 0.3 kg, respectively: LTM (kg) = 0.01464 × (MTSUM×L) (cm2) - 2.767, where MTSUM is the sum of the product of MTs at four sites, and L is length of segment where MT is determined. The estimated LTM (7.0 ± 1.7 kg) did not significantly differ from the measured LTM (7.0 ± 1.7 kg), without a significant systematic error on a Bland-Altman plot. The application of this equation for the cross-validation group (14 women and 11 men) did not yield a significant difference between the measured (7.2 ± 1.6 kg) or estimated (7.2 ± 1.6 kg) LTM and systematic error. Conclusion The developed prediction equation may be useful for estimating the lean tissue mass of the lower extremity for the healthy Japanese middle-aged and older population.
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Jin W, Yamada K, Ikami M, Kaji N, Tokeshi M, Atsumi Y, Mizutani M, Murai A, Okamoto A, Namikawa T, Baba Y, Ohta M. P18 Application of IgY to ELISA, LFDs, and immunopillar chips for detecting staphylococcal enterotoxins in milk and dairy products. Int J Antimicrob Agents 2013. [DOI: 10.1016/s0924-8579(13)70263-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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