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1.
The integral experiment on beryllium with D-T neutrons for verification of tritium breeding 总被引:1,自引:0,他引:1
Yury Verzilov Satoshi Sato Kentaro Ochiai Masayuki Wada Axel Klix Takeo Nishitani 《Fusion Engineering and Design》2007,82(1):1-9
A clean benchmark experiment on beryllium was performed with D-T neutrons at the FNS facility of the Japan Atomic Energy Agency. The main objective was to verify the integral data related to the tritium production on lithium isotopes. Tritium production rates, as well as activation reaction rates were measured inside the beryllium assembly that was shaped as a pseudo-cylindrical slab with an area-equivalent diameter of 628 mm and a thickness of 355 mm. Experimental results were analyzed with a three-dimensional Monte Carlo transport code MCNP-4C and FENDL/MC-2.0, JENDL-3.2/3.3 neutron transport libraries. Evaluation of reaction rates was based on the cross section data taken from the JENDL Dosimetry File and ENDF B-VI data libraries. Analysis shows that all calculation combinations (transport and activation cross section libraries) used for evaluation of reaction rates give data that is agreeable with measured values within 10%. 相似文献
2.
Kentaro Okada Masataka Mori Kazuko Shimazaki Tatsuji Chuman 《Journal of chemical ecology》1991,17(4):695-706
The biological activities of synthetic periplanone analogs, including four candidates of periplanone-A (P-A), were evaluated by behavioral and electroantennogram (EAG) assays. Among 16 periplanone analogs, six compounds evoked pheromonal activity from the male American cockroaches. The threshold dosages of these biological active analogs were 10–105 times lower than that of the known periplanone mimic, germacrene-D. The conformation required for eliciting the pheromonal activity is discussed in terms of the structure-activity relationship of these analogs. Hauptmann's P-A elicited the strongest pheromonal activity among four candidates of P-A in our bioassay, suggesting that Hauptmann's P-A is a natural P-A produced from female cockroaches. 相似文献
3.
Hitomi Natomi Toshihito Saitoh Kentaro Sugano Masao Iwamori Masahisa Fukayama Yoshitaka Nagai 《Lipids》1993,28(8):737-742
The composition of the glycosphingolipids of the human gastrointestinal tract was studied. The major neutral glycosphingolipids
were ceramide monohexosides (e.g., GalCer, GlcCer), LacCer, Gb3Cer, Gb4Cer and more polar ones with more than four sugars, whereas neither Gg3Cer nor Gg4Cer were present. The acidic glycosphingolipids consisted of sulfatides and gangliosides such as GM3, GM1, GD3 and GD1a. Also a large amount of sulfatides was found in the gastric mucosa and duodenum. The concentrations of sulfatides in the
fundic mucosa, antral mucosa and duodenum amounted to 416.0, 933.8 and 682.9 nmol/g of dry weight, respectively, exceeding
those in the gastric mucosa and kidney of other mammals. The major molecular species of the sulfatides were identified as
I3SO3-GalCer with hydroxylated longer-chain fatty acids based on the analyses by gas-liquid chromatography and negative ion fast-atom
bombardment mass spectrometry. In contrast, gangliosides in these regions showed a tendency to be lower than sulfatides, and
the molar ratios of sulfatides to gangliosides were about 2.0, whereas those in other parts were less than 0.5. A high content
of sulfatides in the gastric and duodenal mucosa, where mucosa is easily insulted by acid, pepsin and bile salts, may be closely
related to their roles in mucosal protection.
The nomenclature used for gangliosides and other glycosphingolipids follows the system of Svennerholm (Ref. 1) and the recommendation
of the IUPAC-IUB Commission (Ref. 2), respectively. 相似文献
4.
Surface degradation of polyamide nanocomposites caused by partial discharges using IEC (b) electrodes 总被引:1,自引:0,他引:1
Kozako M. Fuse N. Ohki Y. Okamoto T. Tanaka T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2004,11(5):833-839
Partial discharge (PD) degradation of polyamide both without nanoscale fillers (nanofillers) and with 2,4 and 5 wt% additions of nanofillers was investigated. Such materials were subjected to PDs using the IEC (b) electrodes for evaluation. Comparisons were made as to the surface roughness observed by scanning electron microscopy and atomic force microscopy. It was found that the change in the surface roughness is far smaller in specimens with nanofillers than those without nanofillers, and that the 2 wt% addition is sufficient for improvement of the surface roughness. Furthermore, it was elucidated that the difference of surface roughness of the degraded area due to PDs among the specimens originates from the difference in their crystalline structures. These results indicate that polyamide nanocomposite is more resistance to PDs than polyamide without nanofillers. 相似文献
5.
Galactose and N-acetyl-D-galactosamine-inhibitable lectin of Entamoeba histolytica have roles in the pathogenicity of intestinal amoebiasis. Igl1, the intermediate subunit lectin-1 of E. histolytica, has been shown to have both hemolytic and cytotoxic activities that reside in the C-terminus of the protein. To identify the amino acid regions responsible for these activities, recombinant proteins were prepared and used in hemolytic and cytotoxic assays. The results revealed that Igl1 has multiple domains with hemolytic and cytotoxic activities and that amino acids 787-846, 968-1028 and 1029-1088 are involved in these activities. The hemolytic activities of the fragments were partly inhibited by mannose, galactose and N-acetylgalactosamine, and glucose showed lower or negligible inhibitory effects for the activities. This is the first report of a protozoan protein with hemolytic and cytotoxic activities in multiple domains. 相似文献
6.
Seiichiro Katagiri SungGi Chi Yosuke Minami Kentaro Fukushima Hirohiko Shibayama Naoko Hosono Takahiro Yamauchi Takanobu Morishita Takeshi Kondo Masamitsu Yanada Kazuhito Yamamoto Junya Kuroda Kensuke Usuki Daigo Akahane Akihiko Gotoh 《International journal of molecular sciences》2022,23(9)
KIT is a type-III receptor tyrosine kinase that contributes to cell signaling in various cells. Since KIT is activated by overexpression or mutation and plays an important role in the development of some cancers, such as gastrointestinal stromal tumors and mast cell disease, molecular therapies targeting KIT mutations are being developed. In acute myeloid leukemia (AML), genome profiling via next-generation sequencing has shown that several genes that are mutated in patients with AML impact patients’ prognosis. Moreover, it was suggested that precision-medicine-based treatment using genomic data will improve treatment outcomes for AML patients. This paper presents (1) previous studies regarding the role of KIT mutations in AML, (2) the data in AML with KIT mutations from the HM-SCREEN-Japan-01 study, a genome profiling study for patients newly diagnosed with AML who are unsuitable for the standard first-line treatment (unfit) or have relapsed/refractory AML, and (3) new therapies targeting KIT mutations, such as tyrosine kinase inhibitors and heat shock protein 90 inhibitors. In this era when genome profiling via next-generation sequencing is becoming more common, KIT mutations are attractive novel molecular targets in AML. 相似文献
7.
Takefumi Hiraguri Kengo Nagata Toshiyuki Ogawa Takahiro Ueno Kenya Jin’no Kentaro Nishimori 《Wireless Personal Communications》2013,70(2):985-1000
A transmission queuing scheme is described that increases downlink throughput on wireless local area networks (WLANs) while also increasing the total throughput. When the amount of uplink traffic increases on a WLAN, the carrier sense multiple access with collision avoidance (CSMA/CA) protocol, which is the prescribed scheme for IEEE 802.11 WLAN channel access, may substantially reduce the rate of downlink data frame transmission. This results in severe throughput degradation for mobile stations with downlink traffic. The proposed scheme comprises a transmission control function based on consecutive transmission, as described in the IEEE 802.11e standard, and a dynamic queue prioritization algorithm. Simulation results demonstrate that the proposed scheme increases the maximum total throughput for uplink and downlink traffic by 17% compared with the conventional distributed coordination function (DCF) scheme and that it reduces the difference between uplink and downlink throughput. In an environment where transmission errors occur, the difference in throughput is reduced by about 50% compared with the conventional schemes. 相似文献
8.
Kentaro Okada Masataka Mori Kazuko Shimazaki Tatsuji Chuman 《Journal of chemical ecology》1990,16(9):2605-2614
Bioassays were performed on malePeriplaneta americana L. using synthetic (–)-periplanone-B (P-B) and Hauptmann's (–)-periplanone-A (P-A), and their mixtures at various ratios to estimate the roles of both periplanones for the sexual communication of the species. Both P-A and P-B elicited qualitatively the same responses, such as antennal movement, rapid locomotion, wing raising, and homosexual behavior of male cockroaches, but the threshold of the pheromone activities for P-B was two orders of magnitude lower than that of P-A. Neither synergistic nor inhibitory but only a simple integrated effect on the responses was observed when mixtures of P-A and P-B were applied. 相似文献
9.
10.
Kentaro Yanagihara Jumpei Taketsugu Kiyoshi Fukui Shigeru Fukunaga Shinsuke Hara Ken-ichi Kitayama 《Wireless Personal Communications》2007,40(3):401-415
In this paper, we propose a new energy efficient clustering scheme with transmission power control named “EACLE” (Energy-Aware
CLustering scheme with transmission power control for sEnsor networks) for wireless sensor networks, which are composed of
the following three components; “EACLE clustering” is a distributed clustering method by means of transmission power control,
“EACLE routing” builds a tree rooted at a sink node and sets the paths from sensor nodes taking energy saving into consideration,
and “EACLE transmission timing control” changes the transmission timing with different levels of transmission power to avoid
packet collisions and facilitates packet binding.
With an indoor wireless channel model which we obtained from channel measurement campaigns in rooms and corridors and an energy
consumption model which we obtained from a measurement of a chipset, we performed computer simulations to investigate the
performance of EACLE in a realistic environment. Our simulation results indicate that EACLE outperforms a conventional scheme
such as EAD (Energy-Aware Data-centric routing) in terms of communication success rate and energy consumption. Furthermore,
we fully discuss the impact of transmission power and timing control on the performance of EACLE. 相似文献