A Fast Minimum Cost Flow Algorithm and Its Application to VLSI Layout Compaction

Yuji Shigehiro,Itthichai Arungsrisangchai,Isao Shirakawa,Hiromitsu Takahashi 대한전자공학회 1996 ITC-CSCC :International Technical Conference on Ci Vol.- No.-

Appropriate Color Enhancement Settings for Blue Laser Imaging Facilitates the Diagnosis of Early Gastric Cancer with High Color Contrast

Hiraoka, Yuji,Miura, Yoshimasa,Osawa, Hiroyuki,Nomoto, Yoshie,Takahashi, Haruo,Tsunoda, Masato,Nagayama, Manabu,Ueno, Takashi,Lefor, Alan Kawarai,Yamamoto, Hironori The Korean Gastric Cancer Association 2021 Journal of gastric cancer Vol.21 No.2

Purpose: Screening image-enhanced endoscopy for gastrointestinal malignant lesions has progressed. However, the influence of the color enhancement settings for the laser endoscopic system on the visibility of lesions with higher color contrast than their surrounding mucosa has not been established. Materials and Methods: Forty early gastric cancers were retrospectively evaluated using color enhancement settings C1 and C2 for laser endoscopic systems with blue laser imaging (BLI), BLI-bright, and linked color imaging (LCI). The visibilities of the malignant lesions in the stomach with the C1 and C2 color enhancements were scored by expert and non-expert endoscopists and compared, and the color differences between the malignant lesions and the surrounding mucosa were assessed. Results: Early gastric cancers mainly appeared orange-red on LCI and brown on BLI-bright or BLI. The surrounding mucosae were purple on LCI regardless of the color enhancement but brown or pale green with C1 enhancement and dark green with C2 enhancement on BLI-bright or BLI. The mean visibility scores for BLI-bright, BLI, and LCI with C2 enhancement were significantly higher than those with C1 enhancement. The superiority of the C2 enhancement was not demonstrated in the assessments by non-experts, but it was significant for experts using all modes. The C2 color enhancement produced a significantly greater color difference between the malignant lesions and the surrounding mucosa, especially with the use of BLI-bright (P=0.033) and BLI (P<0.001). C2 enhancement tended to be superior regardless of the morphological type, Helicobacter pylori status, or the extension of intestinal metaplasia around the cancer. Conclusions: Appropriate color enhancement settings improve the visibility of malignant lesions in the stomach and color contrast between the malignant lesions and the surrounding mucosa.

SYNCHROTRON SELF-INVERSE COMPTON RADIATION FROM REVERSE SHOCK ON GRB 120326A

Urata, Yuji,Huang, Kuiyun,Takahashi, Satoko,Im, Myungshin,Yamaoka, Kazutaka,Tashiro, Makoto,Kim, Jae-Woo,Jang, Minsung,Pak, Soojong IOP Publishing 2014 The Astrophysical journal Vol.789 No.2

<P>We present multi-wavelength observations of a typical long duration GRB 120326A at z = 1.798, including rapid observations using a Submillimeter Array (SMA) and a comprehensive monitoring in the X-ray and optical. The SMA observation provided the fastest detection to date among seven submillimeter afterglows at 230 GHz. The prompt spectral analysis, using Swift and Suzaku, yielded a spectral peak energy of E-peak(src) = 107.8(- 15.3)(+15.3) keV and an equivalent isotropic energy of E-iso as 3.18(-0.32)(+0.40) x 10(52) erg. The temporal evolution and spectral properties in the optical were consistent with the standard forward shock synchrotron with jet collimation (6 degrees.69 +/- 0 degrees.16). The forward shock modeling, using a two-dimensional relativistic hydrodynamic jet simulation, was also determined by the reasonable burst explosion and the synchrotron radiation parameters for the optical afterglow. The X-ray light curve showed no apparent jet break and the temporal decay index relation between the X-ray and optical (alpha o - alpha x = -1.45 +/- 0.10) indicated different radiation processes in each of them. Introducing synchrotron self-inverse Compton radiation from reverse shock is a possible solution, and the detection and slow decay of the afterglow in submillimeter supports that this is a plausible idea. The observed temporal evolution and spectral properties, as well as forward shock modeling parameters, enabled us to determine reasonable functions to describe the afterglow properties. Because half of the events share similar properties in the X- ray and optical as the current event, GRB 120326A will be a benchmark with further rapid follow-ups, using submillimeter instruments such as an SMA and the Atacama Large Millimeter/submillimeter Array.</P>

Challenges of Transarticular Screw Fixation in Young Children: Report of Surgical Treatment of a 5-Year-Old Patient’s Unstable Os-Odontoideum

Jun Takahashi,Hiroki Hirabayashi,Hiroyuki Hashidate,Nobuhide Ogihara,Keijiro Mukaiyama,Masatoshi Komatsu,Yuji Inaba,Tomoki Kosho,Hiroyuki Kato 대한척추외과학회 2016 Asian Spine Journal Vol.10 No.5

Surgical procedures for atlantoaxial (C1–C2) fusion in young children are relatively uncommon. The purpose of this study was to report on a surgical treatment for a case of atlantoaxial instability caused by os-odontoideum in association with quadriparesis and respiratory paralysis in a 5-year-old girl. We present the patient’s history, physical examination, and radiographic findings, describe the surgical treatment and a five year follow-up, and provide a literature review. The instability was treated by halo immobilization, followed by C1–C2 transarticular screw fixation using a computed tomography-based navigation system. At the five year follow-up, the patient had made a complete recovery with solid union. The authors conclude that C1–2 transarticular screw fixation is technically possible as in a case of atlantoaxial instability in a five-year-old child.

Intrathoracic anastomosis using handsewn purse-string suturing by the double-ligation method in laparo-thoracoscopic esophagectomy

Takamasa Takahashi,Yuji Kaneoka,Atsuyuki Maeda,Yuichi Takayama,Hiroki Aoyama,Takahiro Hosoi,Kazuaki Seita 대한내시경로봇외과학회 2023 Journal of Minimally Invasive Surgery Vol.26 No.2

Purpose: In minimally invasive esophagectomy (MIE), it is important to reduce the rate of anastomotic leakage to ensure its safety. At our institute, the double-ligation method (DLM) has been introduced to insert and fix the anvil of the circular stapler for intracorporeal circular esophagojejunostomy in gastric surgery. We adopted this method for intrathoracic anastomosis (IA) in MIE. The aim of this study was to investigate the safety of IA with DLM in MIE. Methods: In this study, 48 patients diagnosed with primary middle or lower third segment thoracic esophageal carcinoma with clinical stage I, II, III or IV disease were retrospectively evaluated. Postoperative outcomes were assessed. Results: Among the 48 patients, 42 patients underwent laparo-thoracoscopic esophagectomy and IA using a circular stapler with the DLM. The average total operation time and thoracoscopic operation time were 433 and 229 minutes, respectively. The average pursestring suturing time was 4.7 minutes. The rates of anastomotic leakage and stenosis were 2.4% and 14.3%, respectively. The overall incidence of postoperative complications (Clavien- Dindo grade of ≥III) was 16.7%. The average postoperative stay was 16 days. Conclusion: The procedure of IA using a circular stapler with the DLM in MIE was safe and provided a low rate of anastomotic leakage.

Blue Laser Imaging with a Small-Caliber Endoscope Facilitates Detection of Early Gastric Cancer

Haruo Takahashi,Yoshimasa Miura,Hiroyuki Osawa,Takahito Takezawa,Yuji Ino,Masahiro Okada,Alan Kawarai Lefor,Hironori Yamamoto 대한소화기내시경학회 2019 Clinical Endoscopy Vol.52 No.3

Conventional endoscopy often misses early gastric cancers with minimal red discoloration because they cannot be distinguished frominflamed mucosa. We treated a patient with a small early gastric cancer that was diffcult to diagnose using conventional endoscopy. Conventional endoscopy using a small-caliber endoscope showed only subtle red discoloration of the gastric mucosa. However, bluelaser imaging showed a clearly discolored area measuring 10 mm in diameter around the red lesion, which was distinct from thesurrounding inflamed mucosa. Irregular vessels on the tumor surface (suspicious for early gastric cancer) were observed even withsmall-caliber endoscopy. Biopsy revealed a well-moderately differentiated tubular adenocarcinoma, and endoscopic submucosaldissection was performed. Histopathological examination of the specimen confirmed well-moderately differentiated adenocarcinomalocalized to the mucosa with slight depression compared to the surrounding mucosa, consistent with the endoscopic findings. Thissmall early gastric cancer became clearly visible with blue laser imaging using small-caliber endoscopy.

Development of Wheeled Inverted Pendulum Type Personal Mobility with Pedal

Seonghee Jeong,Yuji Masuda,Yutaka Hiroi,Takayuki Takahashi,Osamu Matsumoto 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

In this paper, the mechanism and basic driving function of a wheeled inverted pendulum-type personal mobility with a pedal (Wi-PMP) are described. The mobility consists of a wheeled inverted pendulum-type mobile platform and a leg rowing mechanism, and thus it can be driven by a rider’s leg rowing motion. Moreover, to retain the merits of pivot turning of a parallel two-wheeled mobility, a differential gear box and a one-way clutch are installed between the pedal and the wheel shafts. It is designed such that a rider can ground his feet while sitting on the saddle. In addition, the Wi-PMP is compact and light-weight, and thus it can be driven and parked in a narrow space. Through experiments using three types of driving mode(motor driving, pedal driving, and assist driving), it was confirmed that mobility can realize all driving modes and pivot turning while keeping the feet of the rider on the pedals.

Electrical conduction properties of La-substituted bismuth titanate single crystals

Masaru Miyayama,Yuji Noguchi,Masatake Takahashi 한양대학교 세라믹연구소 2005 Journal of Ceramic Processing Research Vol.6 No.4

Single crystals of lanthanum-substituted bismuth titanate were grown by a self-flux method, and electrical conductivities were investigated at high temperatures. Lanthanum substitution suppressed Bi vaporization during annealing and decreased the electrical conductivity in both the a- and c-axes. It is suggested that lanthanum substitution stabilizes the perovskite blocks and hence decreases the concentrations of oxygen vacancies and holes as the conduction carriers. An ab-initio calculation indicated that the formation energy of an oxygen vacancy in the perovskite block is increased by lanthanum substitution, supporting the above experimental results.

A Novel Technique of Hand-Sewn Purse-String Suturing by Double Ligation Method (DLM) for Intracorporeal Circular Esophagojejunostomy

Yuichi Takayama,Yuji Kaneoka,Atsuyuki Maeda,Yasuyuki Fukami,Takamasa Takahashi,Masahito Uji 대한위암학회 2019 Journal of gastric cancer Vol.19 No.3

Purpose: The optimal method for intracorporeal esophagojejunostomy remains unclearbecause a purse-string suture for fixing the anvil into the esophagus is difficult to performwith a laparoscopic approach. Therefore, this study aimed to evaluate our novel technique tofix the anvil into the esophagus. Materials and Methods: This retrospective study included 202 patients who were treatedat our institution with an intracorporeal circular esophagojejunostomy in a laparoscopyassistedtotal gastrectomy with a Roux-en-Y reconstruction (166 cases) or a laparoscopyassistedproximal gastrectomy with jejunal interposition (36 cases). After incising 3/4 ofthe esophageal wall, a hand-sewn purse-string suture was placed on the esophagus. Next,the anvil head of a circular stapler was introduced into the esophagus. Finally, the circularesophagojejunostomy was performed laparoscopically. The clinical characteristics andsurgical outcomes were evaluated and compared with those of other methods. Results: The average operation time was 200.3 minutes. The average hand-sewn pursestringsuturing time was 6.4 minutes. The overall incidence of postoperative complications(Clavien–Dindo classification grade ≥II) was 26%. The number of patients with ananastomotic leakage and stenosis at the esophagojejunostomy site were 4 (2.0%) and 12(6.0%), respectively. All patients with stenosis were successfully treated by endoscopicballoon dilatation. There was no mortality. Regarding the materials and devices for anvilfixation, only 1 absorbable thread was needed. Conclusions: Our procedure for hand-sewn purse-string suturing with the double ligationmethod is simple and safe.

Specific-heat Study on Successive Magnetic Transitions in α-Dy2S3 Single Crystals under Magnetic Fields

Shuji Ebisu,Yuji Ushiki,Shin Takahashi 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.3

Specific-heat measurements in magnetic fields have been performed on α-Dy2S3 single crystalsand have shown successive magnetic transitions at TN1 = 11.4 K and TN2 = 6.4 K. The specific heatin no magnetic field exhibits sharp peaks at both TN1 and TN2 . The change in the magnetic entropyacross each transition is estimated as Rln2/2 per mol-Dy, which suggests magnetic moments ononly one Dy site between two crystallographically inequivalent Dy sites order at each transitiontemperature. When the magnetic field is applied along the b-axis of the orthorhombic system, thetwo peaks of the specific heat shift toward lower temperatures. On the other hand, a magnetic fieldperpendicular to the b-axis shifts the peaks toward higher temperatures. The TN1 shifts to 9.6 K(H k b) and 12.5 K (H ⊥ b) under a magnetic field of 2 T. The TN2 peak broadens gradually withincreasing magnetic field for each direction; consequently, the peak is obscure under a field of 2 T.