Response of a Plate-type Thermoluminescence Dosimeter to a Therapeutic Carbon Beam

Yusuke Koba,Shigekazu Fukuda,Kiyomitsu Shinsho,Genichiro Wakabayashi,Satoshi Tamatsu 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.7

In order to measure the three-dimensional dose distribution in X-ray radiotherapy, we developeda plate-type thermoluminescence dosimeter (TLD) using the TL phosphor Li3B7O12:Cu, which hasZeff = 7.42 and a density of 1.01 gcm−3. This detector was expected on useful application inadvanced X-ray radiotherapies such as intensity-modulated ratiation therapy (IMRT) etc., becauseit can obtain 3D dose measurements simply and quickly with a single exposure. In this paper, wereport the response of this plate-type TLD to a therapeutic carbon beam at the Heavy Ion MedicalAccelerator in Chiba (HIMAC). Using a plate heater and charge coupled device (CCD) camera, wecaptured thermoluminescence images of plate-type TLDs irradiated by a therapeutic carbon beam. The TL intensity was measured at each water equivalent depth and compared with output of theionization chamber. The relative TL efficiency of this TLD as 60Co gamma-ray equivalent decreasedgradually with increasing dose-averaged linear-energy-transfer (LET), reaching about 20% at theBragg peak of 290 MeV/u carbon ions.

Sustainable Olympic Development: A Proposed Benchmark for Managing Economic Outcomes

Timothy Koba,Hua Gong,Walker J. Ross,John Grady 글로벌지식마케팅경영학회 2021 Journal of Global Sport Management Vol.6 No.1

No other sporting event possesses the grandeur of the Olympics, and few other development projects demonstrate the lack of cost containment as the Olympics which leaves local residents paying the debt and maintenance of a venue they may never use. Legacy planning is an important consideration for the hosting of the Olympics, but one that does not always receive adequate consideration resulting in the “white elephant phenomenon.” This study therefore looked to analyze the cost of hosting the Olympics compared to the economic activity in the host community in order to better inform public policy on the issues of sustainability and legacy, in particular. We are proposing a metric that helps to measure the costs that Olympic hosting has on the host community and provide a benchmark for containing those costs in terms of budgeting, construction and legacy planning for the Games. Consequently, the IOC can institute policy changes for project management that assist host cities in establishing a budget cap for venue development while simultaneously seeking to reduce the crippling debt that has accompanied them in the past.

Estimation of traveling direction of car body using optical flow derived from onboard camera

Hiromichi Koba,Teruo Yamaguchi,Hiroshi Harada 제어로봇시스템학회 2018 제어로봇시스템학회 국제학술대회 논문집 Vol.2018 No.10

In recent years, increase of traffic accidents by elderly people has become serious problem in Japan. Causes of accidents include decline in cognitive function and muscular strength. If they are given many diagnostic opportunities, they can selftest their driving ability. We propose a method of measuring the position of the FOE and the average of the horizontal speed in the image to estimate the direction of travel of the car. We examined possibility of estimating the direction of travel of the car body from images of using onboard cameras image. Experimental results showed that possibility of estimating the direction of travel can be achieved.

Circumferential gastric wall thickening as initial presentation of relapsed plasma cell leukemia

Yusuke Koba,Takahito Kawata,Akira Tamekane,Mitsumasa Watanabe 대한소화기내시경학회 2024 Clinical Endoscopy Vol.57 No.1

BRIEF REPORT

An Exploration of Professional U.S.-Based Basketball Players Competing in Turkey

Timothy H. Koba,Mark S. Nagel,Nicholas M. Watanabe,Grace Yan,Richard M. Southall,Victor K. Kidd 글로벌지식마케팅경영학회 2023 Journal of Global Sport Management Vol.8 No.1

In the wake of the 1992 Barcelona Summer Olympic Games, bas- ketball experienced a surge in popularity as an international sport. Recently, to field more competitive teams, professional leagues around the world have begun to recruit international players, par- ticularly those from the United States (U.S.). Though most leagues still maintain strict caps on the number of players from a single country on a roster, the Turkey Basketball Federation (TBF) recently altered its rules to permit more international players, presenting American players greater opportunities to pursue a lucrative play- ing career in Turkey. Given the change in labor market characteris- tics, this paper examines the 102 U.S. players on 2017–2018 Turkey professional basketball rosters. Descriptive statistics for collegiate performance are presented, as well as logistic regression and net- work analyses that indicate players’ college choice was a crucial factor in their international professional career trajectory with colle- giate conference acting as a bridge to a professional career in Turkey. These results provide context for researchers and practi- tioners in understanding the player statistics, social and cultural forces related to U.S.-professional basketball players in Turkey.

CO-CULTURE OF BOVINE EMBRYOS WITH CUMULUS CELLS

Goto, K.,Koba, M.,Takuma, Y.,Nakanishi, Y.,Ogawa, K. Asian Australasian Association of Animal Productio 1989 Animal Bioscience Vol.2 No.4

Bovine embryos/ova obtained from in-vitro fertilization were either co-cultured on a monolayer of bovine cumulus cells or cultured in medium alone. Embryos/ova co-cultured with cumulus cells developed to 8-cell (30.9%), morula (29.8%) and blastocyst stages (26.6%) after 3-4, 5-6, and 7-8 days of culture, respectively, while embryos/ova cultured in medium alone failed to develop beyond 8-cell (0-13.3%), morula (0-1.5%) and blastocyst stages (0%). The results of this study demonstrated the beneficial effect of cumulus cells on the development of bovine embryos.

A mutant strain Arabidopsis thaliana that lacks vacuolar membrane zinc transporter MTP1 revealed the latent tolerance to excessive zinc.

Kawachi, Miki,Kobae, Yoshihiro,Mori, Haruki,Tomioka, Rie,Lee, Youngsook,Maeshima, Masayoshi Japanese Society of Plant Physiologists 2009 Plant & cell physiology Vol.50 No.6

<P>A mutant line of Arabidopsis thaliana that lacks a vacuolar membrane Zn(2+)/H(+) antiporter MTP1 is sensitive to zinc. We examined the physiological changes in this loss-of-function mutant under high-Zn conditions to gain an understanding of the mechanism of adaptation to Zn stress. When grown in excessive Zn and observed using energy-dispersive X-ray analysis, wild-type roots were found to accumulate Zn in vacuolar-like organelles but mutant roots did not. The Zn content of mutant roots, determined by chemical analysis, was one-third that of wild-type roots grown in high-Zn medium. Severe inhibition of root growth was observed in mtp1-1 seedlings in 500 muM ZnSO(4). Suppression of cell division and elongation by excessive Zn was reversible and the cells resumed growth in normal medium. In mutant roots, a marked formation of reactive oxygen species (ROS) appeared in the meristematic zone, where the MTP1 gene was highly expressed. Zn treatment enhanced the expression of several genes involved in Zn tolerance: namely, the plasma membrane Zn(2+)-export ATPase, HMA4, and plasma and vacuolar membrane proton pumps. CuZn-superoxide dismutases, involved in the detoxification of ROS, were also induced. The expression of plasma membrane Zn-uptake transporter, ZIP1, was suppressed. The up- or down-regulation of these genes might confer the resistance to Zn toxicity. These results indicate an essential role of MTP1 in detoxification of excessive Zn and provide novel information on the latent adaptation mechanism to Zn stress, which is hidden by MTP1.</P>

MODULAR INVARIANTS UNDER THE ACTIONS OF SOME REFLECTION GROUPS RELATED TO WEYL GROUPS

Ishiguro, Kenshi,Koba, Takahiro,Miyauchi, Toshiyuki,Takigawa, Erika Korean Mathematical Society 2020 대한수학회보 Vol.57 No.1

Some modular representations of reflection groups related to Weyl groups are considered. The rational cohomology of the classifying space of a compact connected Lie group G with a maximal torus T is expressed as the ring of invariants, H*(BG; ℚ) ≅ H*(BT; ℚ)^W(G), which is a polynomial ring. If such Lie groups are locally isomorphic, the rational representations of their Weyl groups are equivalent. However, the integral representations need not be equivalent. Under the mod p reductions, we consider the structure of the rings, particularly for the Weyl group of symplectic groups Sp(n) and for the alternating groups A_n as the subgroup of W(SU(n)). We will ask if such rings of invariants are polynomial rings, and if each of them can be realized as the mod p cohomology of a space. For n = 3, 4, the rings under a conjugate of W(Sp(n)) are shown to be polynomial, and for n = 6, 8, they are non-polynomial. The structures of H*(BT^n-1; 𝔽_p)^A_n will be also discussed for n = 3, 4.

Reactive dye effluent treatment with peroxide-assisted ozonation: Effects of persulfate, peracetic acid and percarbonate

Arslan-Alaton Idil,Koba-Ucun Olga,Farasat Shima 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.11

Simulated reactive dyebath effluent (pH≈11.0–11.5) bearing the commercially important textile azo dye Reactive Red 21 (100 mg/L) can be successfully decolorized via ozone (feed rate=72 mg/min) and peroxide (=0.75–6.00 mM)/ozone treatment processes. Persulfate (PS), peracetic acid (PAA) and percarbonate (PC) were selected as alternative oxidants to the more conventional hydrogen peroxide. Color (peak absorbance) and total organic carbon (TOC) removals increased with increasing PS concentration, but decreased when PC was introduced due to free radical scavenging effects of carbonate alkalinity. PAA improved color and TOC removal rates, but thereby also contributed to the TOC content of the dyebath effluent. PAA-assisted ozonation showed the highest performance in terms of color removal at an optimum PAA concentration (=1.5 mM). According to the gas phase-and-dissolved ozone measurements, addition of the peroxides PS-PAA enhanced ozone decomposition and increased ozone absorption rates whereas PC addition stabilized aqueous, molecular ozone. The originally non-toxic reactive dyebath effluent (≈10% relative inhibition) did not exhibit serious acute toxicity towards Vibrio fischeri photobacterium throughout ozonation and ozone/PS treatment, whereas a slight increase was observed for ozone/PAA-ozone/PC that decreased with applied ozone dose. The 7th-day-biochemical-oxygen-demand (BOD7; <10 mg/L) decreased with ozone dose speaking for less biodegradable oxidation products.

PREGNANCY IN CATTLE AFTER TRANSFER OF BISECTED BLASTOCYSTS OBTAINED FROM IN-VITRO FERTILIZATION OF OOCYTES MATURED IN-VITRO

Goto, K.,Kajihara, Y.,Koba, M.,Nakanishi, Y.,Ogawa, K. Asian Australasian Association of Animal Productio 1988 Animal Bioscience Vol.1 No.3

Bovine blastocysts were obtained by in-vitro culture of embryos derived from in-vitro fertilization of oocytes matured in-vitro. These blastocysts and blastocysts from inseminated donors were bisected by a simple method (without a holding pipette) using a microblade operated by a micromanipulator. A pair of demi-embryos was transferred nonsurgically into each uterine horn of a recipient cow 6 or 8 days after estrus. Pregnancy resulted from the third transfer. Ultrasound examination done 52 days after estrus (46 days after transfer) confirmed the presence of at least one fetus in the each uterine horn. This is the first report to show the viability of bisected bovine blastocysts obtained from in-vitro culture of embryos derived from in-vitro fertilization of oocytes matured in-vitro. In addition, a simple method to bisect bovine embryos is described.