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Rare-metal-free high-performance Ga-Sn-O thin film transistor

Tokiyoshi Matsuda, Kenta Umeda, Yuta Kato, Daiki Nishimoto, Mamoru Furuta, Mutsumi Kimura
2017 Scientific Reports  
Kenta Umeda fabricated and characterised the TFTs. Yuta Kato developed the GTO TFT fabrication process. Daiki Nishimoto carried out the deposition and evaluation of the films.  ... 
doi:10.1038/srep44326 pmid:28290547 pmcid:PMC5349530 fatcat:vgdhascyfzgblbku5udpir7shu

Resonance-suppression Control for Electro-hydrostatic Actuator as Two-inertia System

Kenta Tsuda, Tomoki Sakuma, Kodai Umeda, Sho Sakaino, Toshiaki Tsuji
2017 IEEJ Journal of Industry Applications  
Experimental Setup Servo Pump Charge Pump Resonance-suppression Control for EHA as Two-inertia System Kenta Tsuda et al.  ... 
doi:10.1541/ieejjia.6.320 fatcat:55qycp2dfrg5bbrezgi65tbkoe

Reaction Force Estimation of Electro-hydrostatic Actuator Using Reaction Force Observer

Kodai Umeda, Tomoki Sakuma, Kenta Tsuda, Sho Sakaino, Toshiaki Tsuji
2018 IEEJ Journal of Industry Applications  
Electro-hydrostatic actuators (EHAs) are hydraulic actuators that are flexible and exhibit high backdrivability. Flexible operation and accurate detection of reaction forces are required for robots to be able to perform in environments in which they will be cohabiting with humans. However, nonlinear elements that degrade detection accuracy, such as static friction, backlash, and oil leakage, are present in hydraulic systems. In addition, pressure sensors in hydraulic systems are not very
more » ... e at estimating reaction forces, because they cannot estimate internal forces and viscous friction. In this study, we propose a combination of control algorithms for accurately estimating reaction forces. Static friction is compensated by using feedback modulators. In addition, we use a backlash and oil leakage compensator, which do not require any models, to suppress the relative velocity between the motor-side and load-side. Then, the use of a reaction force observer (RFOB) that exploits both pressure sensors and encoders is proposed. The RFOB can be implemented because disturbances are linearized by the compensators. Experimental results show that reaction forces can be estimated with very high accuracy using the proposed RFOB. In addition, we implemented force control using the RFOB and evaluate the force tracking performances by improving the estimation accuracy.
doi:10.1541/ieejjia.7.250 fatcat:pexr7c3lcfhxlblgmfh3r3o47e

Genome-wide analysis of transcriptional bursting-induced noise in mammalian cells [article]

Hiroshi Ochiai, Tetsutaro Hayashi, Mana Umeda, Mika Yoshimura, Akihito Harada, Yukiko Shimizu, Kenta Nakano, Noriko Saitoh, Hiroshi Kimura, Zhe Liu, Takashi Yamamoto, Tadashi Okamura (+2 others)
2019 bioRxiv   pre-print
Cell-to-cell heterogeneity in gene expression even occurs among cells of the same type in a similar environment. Transcriptional bursting is considered a contributing factor to the heterogeneity, but it remains elusive how the kinetic properties of transcriptional bursting (e.g., burst size, burst frequency, and noise induced by transcriptional bursting) are regulated in mammalian cells. Results: In this study, we performed a genome-wide analysis of transcriptional bursting in mouse embryonic
more » ... em cells (mESCs) using single-cell RNA-sequencing. We found that the kinetics of transcriptional bursting was determined by a combination of promoter and gene body binding proteins, including polycomb repressive complex 2 and transcription elongation-related factors. Furthermore, large-scale CRISPR-Cas9-based screening and functional analysis revealed that the Akt/MAPK signaling pathway regulated bursting kinetics by modulating transcription elongation efficiency. Conclusions: We found that the kinetics of transcriptional bursting was determined by a combination of promoter and gene body binding proteins, including PRC2 and transcription elongation-related factors. These data uncover key molecular determinants controlling transcriptional bursting and cell-to-cell gene expression noise in mammalian cells.
doi:10.1101/736207 fatcat:4a7755vatzguxpinlmp5xfhefq

Integrated multigene expression panel to prognosticate patients with gastric cancer

Mitsuro Kanda, Kenta Murotani, Haruyoshi Tanaka, Takashi Miwa, Shinichi Umeda, Chie Tanaka, Daisuke Kobayashi, Masamichi Hayashi, Norifumi Hattori, Masaya Suenaga, Suguru Yamada, Goro Nakayama (+2 others)
2018 OncoTarget  
Most of the proposed individual markers had limited clinical utility due to the inherent biological and genetic heterogeneity of gastric cancer. We aimed to build a new molecular-based model to predict prognosis in patients with gastric cancer. A total of 200 patients who underwent gastric resection for gastric cancer were divided into learning and validation cohorts using a table of random numbers in a 1:1 ratio. In the learning cohort, mRNA expression levels of 15 molecular markers in gastric
more » ... tissues were analyzed and concordance index (C-index) values of all single and combinations of the 15 candidate markers for overall survival were calculated. The multigene expression panel was designed according to C-index values and the subpopulation index. Expression scores were determined with weighting according to the coefficient of each constituent. The reproducibility of the panel was evaluated in the validation cohort. C-index values of the 15 single candidate markers ranged from 0.506-0.653. Among 32,767 combinations, the optimal and balanced expression panel comprised four constituents (MAGED2, SYT8, BTG1, and FAM46) and the C-index value was 0.793. Using this panel, patients were provisionally categorized with scores of 1-3, and clearly stratified into favorable, intermediate, and poor overall survival groups. In the validation cohort, both overall and disease-free survival rates decreased incrementally with increasing expression scores. Multivariate analysis revealed that the expression score was an independent prognostic factor for overall survival after curative gastrectomy. We developed an integrated multigene expression panel that simply and accurately stratified risk of patients with gastric cancer.
doi:10.18632/oncotarget.24661 pmid:29721160 pmcid:PMC5922354 fatcat:nrfqtq63rnfrvgziocqtehcfsq

Comparison of 3 Devices for Automated Infusion of Positron-Emitting Radiotracers

Noriaki Miyaji, Kenta Miwa, Kei Wagatsuma, Taisuke Murata, Takuro Umeda, Takashi Terauchi, Mitsuru Koizumi
2017 Journal of Nuclear Medicine Technology  
The administration accuracy and precision of an automated infusion device for positron-emitting radiotracers are directly associated with bias and variance in the SUVs of 18 F-FDG PET/CT. Therefore, the accuracy of such devices must be confirmed and calibrated at locations in which they are used. The present study aimed to validate the administration accuracy of 3 automated infusion devices for quantitative PET assessment. Methods: Temporal variations as well as variations in radioactive
more » ... rations and dispensed volumes of 18 F-FDG were determined for the M-130, AI-300, and UG-05 automated infusion devices. The total-test dispensed volumes were 25, 20, and 18.5 mL, respectively. A reference value was generated by measuring amounts of radioactivity using a standard dose calibrator. Administration accuracy was validated according to the criteria of the Japanese Society of Nuclear Medicine. Results: The temporal variation in the M-130 and UG-05 for a specified 185 MBq was relatively stable, in the range of −1.60%-0.92% and 1.16%-5.35%, respectively, whereas that in the AI-300 was −0.55%-8.68%. For the M-130 and UG-05 devices, the difference between measured and reference value was in the range of −5%-5%. The values measured by the AI-300 deviated from the reference values by a maximum of 30%, which depends on radioactive concentration and dispensed volume of 18 F-FDG. Conclusion: The administration accuracy of the AI-300 varied considerably under different conditions, but a software update might somewhat improve this. Our findings indicate that dispensed volumes of 18 F-FDG should be carefully considered when the radioactive concentration is high. Administration accuracy should be regularly confirmed at each location to maintain the quality of quantitative PET assessment. The present study provides useful information about how to confirm the administration accuracy of automated infusion devices.
doi:10.2967/jnmt.116.188243 pmid:28280125 fatcat:ad53aijd5fa3daecbzhtazd2o4

Technical Features and Roles of Cobalt-57 Flood Sources for Daily Quality Control of Gamma Cameras

Kei Wagatsuma, Kenta Miwa, Kenta Akimoto, Hiroyuki Tsushima, Noriaki Miyaji, Takuro Umeda, Taisuke Murata, Tomohiro Takiguchi, Mitsuru Koizumi
2014 Japanese Journal of Radiological Technology  
Quality control (QC) detects changes in the performance of gamma cameras that could adversely affect interpretations of clinical studies. We used plate and sheet 57 Co flood sources to measure extrinsic uniformity during daily QC. Each source, when placed on the top of a collimated detector, allowed the acquisition of uniform images from both detectors, thus reducing the amount of time needed to perform daily QC. No serious problems with the gamma camera system were revealed by visual checks,
more » ... d changes in detector sensitivity were rapidly determined by observing daily variations in the measured values of extrinsic uniformity. Furthermore, 57 Co flood sources confer advantages in that they shorten the time required for preparation of flood sources and reduce the consequent exposure of medical staff to radiation.
doi:10.6009/jjrt.2014_jsrt_70.2.148 pmid:24573229 fatcat:rktdrhlfuzdchggafzrxzj4g4e

Development of a Special-Purpose Processor for Molecular Orbital Calculations

Kenta NAKAMURA, Hiroaki HONDA, Hiroaki UMEDA, Harunobu KOMATSU, Kazuaki MURAKAMI
2005 Journal of Computer Chemistry, Japan  
SIG 1 (HPS6) pp. 1-9 (2003 Development of a Special-Purpose Processor for Molecular Orbital Calculations Kenta NAKAMURA a *, Hiroaki HONDA b *, Hiroaki UMEDA c , Ab initio molecular orbital (MO) calculation  ... 
doi:10.2477/jccj.4.155 fatcat:aljguyi6cfbr5dz5ltxrivpl5y

Genome-wide kinetic properties of transcriptional bursting in mouse embryonic stem cells

Hiroshi Ochiai, Tetsutaro Hayashi, Mana Umeda, Mika Yoshimura, Akihito Harada, Yukiko Shimizu, Kenta Nakano, Noriko Saitoh, Zhe Liu, Takashi Yamamoto, Tadashi Okamura, Yasuyuki Ohkawa (+2 others)
2020 Science Advances  
Transcriptional bursting is the stochastic activation and inactivation of promoters, contributing to cell-to-cell heterogeneity in gene expression. However, the mechanism underlying the regulation of transcriptional bursting kinetics (burst size and frequency) in mammalian cells remains elusive. In this study, we performed single-cell RNA sequencing to analyze the intrinsic noise and mRNA levels for elucidating the transcriptional bursting kinetics in mouse embryonic stem cells. Informatics
more » ... yses and functional assays revealed that transcriptional bursting kinetics was regulated by a combination of promoter- and gene body–binding proteins, including the polycomb repressive complex 2 and transcription elongation factors. Furthermore, large-scale CRISPR-Cas9–based screening identified that the Akt/MAPK signaling pathway regulated bursting kinetics by modulating transcription elongation efficiency. These results uncovered the key molecular mechanisms underlying transcriptional bursting and cell-to-cell gene expression noise in mammalian cells.
doi:10.1126/sciadv.aaz6699 pmid:32596448 pmcid:PMC7299619 fatcat:iz27zwj4mrhylfxoi4md3fqaem

Administration Accuracy of Automated Infusion Device for PET Using Improved Disposable Kit

Noriaki Miyaji, Kazuki Motegi, Shohei Fukai, Naoki Shimada, Kenta Miwa, Shuto Nakazawa, Takuro Umeda, Tomohiro Takiguchi, Takashi Terauchi, Mitsuru Koizumi
2018 Japanese Journal of Radiological Technology  
doi:10.6009/jjrt.2018_jsrt_74.6.539 pmid:29925748 fatcat:y2cprwqvjzg6no22fholprdg6e

Evaluation of spatial dependence of point spread function-based PET reconstruction using a traceable point-like 22Na source

Taisuke Murata, Kenta Miwa, Noriaki Miyaji, Kei Wagatsuma, Tomoyuki Hasegawa, Keiichi Oda, Takuro Umeda, Takashi Iimori, Yoshitada Masuda, Takashi Terauchi, Mitsuru Koizumi
2016 EJNMMI Physics  
The point spread function (PSF) of positron emission tomography (PET) depends on the position across the field of view (FOV). Reconstruction based on PSF improves spatial resolution and quantitative accuracy. The present study aimed to quantify the effects of PSF correction as a function of the position of a traceable point-like 22 Na source over the FOV on two PET scanners with a different detector design. Methods: We used Discovery 600 and Discovery 710 (GE Healthcare) PET scanners and
more » ... le point-like 22 Na sources (<1 MBq) with a spherical absorber design that assures uniform angular distribution of the emitted annihilation photons. The source was moved in three directions at intervals of 1 cm from the center towards the peripheral FOV using a three-dimensional (3D)-positioning robot, and data were acquired over a period of 2 min per point. The PET data were reconstructed by filtered back projection (FBP), the ordered subset expectation maximization (OSEM), OSEM + PSF, and OSEM + PSF + time-of-flight (TOF). Full width at half maximum (FWHM) was determined according to the NEMA method, and total counts in regions of interest (ROI) for each reconstruction were quantified. Results: The radial FWHM of FBP and OSEM increased towards the peripheral FOV, whereas PSF-based reconstruction recovered the FWHM at all points in the FOV of both scanners. The radial FWHM for PSF was 30-50 % lower than that of OSEM at the center of the FOV. The accuracy of PSF correction was independent of detector design. Quantitative values were stable across the FOV in all reconstruction methods. The effect of TOF on spatial resolution and quantitation accuracy was less noticeable. Conclusions: The traceable 22 Na point-like source allowed the evaluation of spatial resolution and quantitative accuracy across the FOV using different reconstruction methods and scanners. PSF-based reconstruction reduces dependence of the spatial resolution on the position. The quantitative accuracy over the entire FOV of the PET system is good, regardless of the reconstruction methods, although it depends slightly on the position.
doi:10.1186/s40658-016-0162-3 pmid:27783373 pmcid:PMC5080272 fatcat:xwwi5azcyrezdkxg2znkvy6h7i

An integrated multigene expression panel to predict long-term survival after curative hepatectomy in patients with hepatocellular carcinoma

Mitsuro Kanda, Kenta Murotani, Hiroyuki Sugimoto, Takashi Miwa, Shinichi Umeda, Masaya Suenaga, Masamichi Hayashi, Norifumi Hattori, Chie Tanaka, Daisuke Kobayashi, Suguru Yamada, Michitaka Fujiwara (+1 others)
2017 OncoTarget  
Hepatocellular carcinoma (HCC) frequently recurs even after curative hepatectomy. To develop an integrated multigene expression panel, 144 patients were randomly assigned to either discovery or validation set in a 1:2 ratio. Using surgically resected HCC specimens, expression levels of 12 candidate molecular markers were determined using quantitative reverse-transcriptase PCR. In the discovery set, an expression panel was developed according to the concordance index (C-index) values for overall
more » ... survival from all 4095 combinations of the 12 candidate molecular markers. Expression scores was determined with weighting according to the coefficient in a Cox regression, and patients were classified into grade 1, 2 and 3. Reproducibility was then tested in the validation set. A panel consisting of four markers, PRMT5, MAGED4, DPYSL3 and AJAP1 was selected as the optimal and most well-balanced set with a C-index value of 0.707. Patient prognosis was clearly stratified by the expression grade using this panel. In the validation set, both overall and disease-free survival rates decreased incrementally with as the grade increased. Higher grades were significantly associated with tumor multiplicity and vessel invasion. The prevalence of extrahepatic recurrences was increased in grade 3 patients. The integrated multigene expression panel clearly stratified HCC patients into low, intermediate and high risk.
doi:10.18632/oncotarget.20369 pmid:29050343 pmcid:PMC5642618 fatcat:mmvrvvoilfdcbji42fpnu6iflm

Nicotine blocks apomorphine-induced disruption of prepulse inhibition of the acoustic startle in rats: possible involvement of central nicotinicα7receptors

Katsuya Suemaru, Kayo Yasuda, Kenta Umeda, Hiroaki Araki, Kazuhiko Shibata, Tominari Choshi, Satoshi Hibino, Yutaka Gomita
2004 British Journal of Pharmacology  
1 Nicotine has been reported to normalize deficits in auditory sensory gating in the cases of schizophrenia, suggesting an involvement of nicotinic acetylcholine receptors in attentional abnormalities. However, the mechanism remains unclear. The present study investigated the effects of nicotine on the disruption of prepulse inhibition (PPI) of the acoustic startle response induced by apomorphine or phencyclidine in rats. 2 Over the dose range tested, nicotine (0.05-1 mg kg À1 , s.c.) did not
more » ... srupt PPI. Neither methyllycaconitine (0.5-5 mg kg À1 , s.c.), an a 7 nicotinic receptor antagonist, nor dihydro-berythroidine (0.5-2 mg kg À1 , s.c.), an a 4 b 2 nicotinic receptor antagonist, had any effect on PPI. 3 Nicotine (0.01-0.2 mg kg À1 , s.c.) dose-dependently reversed the disruption of PPI induced by apomorphine (1 mg kg À1 , s.c.), but had no effect on the disruption of PPI induced by phencyclidine (2 mg kg À1 , s.c.). 4 The reversal of apomorphine-induced PPI disruption by nicotine (0.2 mg kg À1 ) was eliminated by mecamylamine (1 mg kg À1 , i.p.), but not by hexamethonium (10 mg kg À1 , i.p.), indicating the involvement of central nicotinic receptors. 5 The antagonistic action of nicotine on apomorphine-induced PPI disruption was dose-dependently blocked by methyllycaconitine (1 and 2 mg kg À1 , s.c.). However, dihydro-b-erythroidine (1 and 2 mg kg À1 , s.c.) had no effect. 6 These results suggest that nicotine reverses the disruption of apomorphine-induced PPI through central a 7 nicotinic receptors.
doi:10.1038/sj.bjp.0705855 pmid:15197106 pmcid:PMC1575066 fatcat:lfpmjrdupvc3bmm34qsy7drevm

A novel dual-marker expression panel for easy and accurate risk stratification of patients with gastric cancer

Mitsuro Kanda, Kenta Murotani, Haruyoshi Tanaka, Takashi Miwa, Shinichi Umeda, Chie Tanaka, Daisuke Kobayashi, Masamichi Hayashi, Norifumi Hattori, Masaya Suenaga, Suguru Yamada, Goro Nakayama (+2 others)
2018 Cancer Medicine  
Development of specific biomarkers is necessary for individualized management of patients with gastric cancer. The aim of this study was to design a simple expression panel comprising novel molecular markers for precise risk stratification. Patients (n = 200) who underwent gastrectomy for gastric cancer were randomly assigned into learning and validation sets. Tissue mRNA expression levels of 15 candidate molecular markers were determined using quantitative PCR analysis. A dual-marker
more » ... panel was created according to concordance index (C-index) values of overall survival for all 105 combinations of two markers in the learning set. The reproducibility and clinical significance of the dual-marker expression panel were evaluated in the validation set. The patient characteristics of the learning and validation sets were well balanced. The C-index values of combinations were significantly higher compared with those of single markers. The panel with the highest C-index (0.718) of the learning set comprised SYT8 and MAGED2, which clearly stratified patients into low-, intermediate-, and high-risk groups. The reproducibility of the panel was demonstrated in the validation set. High expression scores were significantly associated with larger tumor size, vascular invasion, lymph node metastasis, peritoneal metastasis, and advanced disease. The dual-marker expression panel provides a simple tool that clearly stratifies patients with gastric cancer into low-, intermediate-, and high risk after gastrectomy. Cancer Medicine Open Access 2464
doi:10.1002/cam4.1522 pmid:29733517 pmcid:PMC6010733 fatcat:6fomnkun3nelnfqhhhd5p5thbi

Preoperative prognostic nutritional index predicts postoperative infectious complications and oncological outcomes after hepatectomy in intrahepatic cholangiocarcinoma

Tatsuo Matsuda, Yuzo Umeda, Tadakazu Matsuda, Yoshikatsu Endo, Daisuke Sato, Toru Kojima, Kenta Sui, Masaru Inagaki, Tetsuya Ota, Masayoshi Hioki, Masahiro Oishi, Masashi Kimura (+4 others)
2021 BMC Cancer  
Yuzo UMEDA: Study design, data analysis, and writing.  ...  Funding Financial support was received from the Japan Society for the Promotion of Science (grant number 19 K09217 to Yuzo UMEDA).  ... 
doi:10.1186/s12885-021-08424-0 pmid:34130648 fatcat:qls47p6a7ne65nakjbxad6kpim
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