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排序方式: 共有473条查询结果,搜索用时 31 毫秒
101.
Four tufted capuchin monkeys (Cebus apella) were trained to choose from 2 hook-like tools, 1 of which successfully led to collecting food, whereas the other did not because of inappropriate spatial arrangement of the tool and the food. In Experiment 1, all of the monkeys successfully learned the basic task. The monkeys performed successfully with tools of novel colors and shapes in Experiments 2-5. These results demonstrate that the monkeys used the spatial arrangement of the tool and the food as a cue. However, they failed when there were obstacles (Experiment 6) or traps (Experiment 7) on the path along which she monkeys dragged tools. These results may suggest that capuchin monkeys understand the spatial relationship between 2 items, namely, food and. the tool, but do not understand the spatial relationship among 3 items, namely, food, tool, and the environmental condition. The possible role of stimulus generalization is also considered. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
Shigeo Asai Kunihito Koumoto Yushu Matsushita Eiji Yashima Masahiko Morinaga Kunihiko Takeda 《Science and Technology of Advanced Materials》2013,14(5):421-433
The center of excellence (COE) titled ‘The Creation of Nature-Guided Materials Processing’ has been established in Nagoya University as the 21st Century COE Program supported by Ministry of Education, Culture, Sports, Science and Technology. In the Nature COE, various activities on the education and research are being performed through learning the laws of nature, namely, methods of attaining ‘appearance of the maximum function under the minimum substance and energy consumption’, which the nature and living organisms have acquired through their evolution in long period. Together with such educational programs for PhD students as research incentive, oversea training, and external evaluation programs, an ‘Open-Cluster Program’ was originated for promoting researches proposed by research groups consisting of young researchers in and out of the university and also for fostering them.The researches are being advanced on materials used for living bodies, mimicking structures which nature or living bodies are forming, and producing materials by mimicking processes to form the structures observed in the nature or the living bodies. In this COE, these researches are conducted by four groups to extend the processes observed in the natural world to a new type of processing, that is, thoroughly examined and rationalized by plunging a scalpel of engineering and to establish a new academic field of materials science and engineering. 相似文献
103.
Shin Takasawa Ryogo Shobatake Yoshinori Takeda Tomoko Uchiyama Akiyo Yamauchi Mai Makino Sumiyo Sakuramoto-Tsuchida Keito Asai Hiroyo Ota Asako Itaya-Hironaka 《International journal of molecular sciences》2022,23(11)
Sleep apnea syndrome (SAS), characterized by recurrent episodes of oxygen desaturation and reoxygenation (intermittent hypoxia (IH)), is a risk factor for hypertension and insulin resistance. We report a correlation between IH and insulin resistance/diabetes. However, the reason why hypertension is induced by IH is elusive. Here, we investigated the effect of IH on the expression of catecholamine-metabolizing enzymes using an in vitro IH system. Human and mouse neuroblastoma cells (NB-1 and Neuro-2a) were exposed to IH or normoxia for 24 h. Real-time RT-PCR revealed that IH significantly increased the mRNA levels of dopamine β-hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) in both NB-1 and Neuro-2a. Western blot showed that the expression of DBH and PNMT in the NB-1 cells was significantly increased by IH. Reporter assays revealed that promoter activities of DBH and PNMT were not increased by IH. The miR-375 level of IH-treated cells was significantly decreased relative to that of normoxia-treated cells. The IH-induced up-regulation of DBH and PNMT was abolished by the introduction of the miR-375 mimic, but not by the control RNA. These results indicate that IH stress increases levels of DBH and PNMT via the inhibition of miR-375-mediated mRNA degradation, potentially playing a role in the emergence of hypertension in SAS patients. 相似文献
104.
R Mizukane M Nakatomi Y Futsuki J Araki S Asai K Sawatari Y Hirakata S Maesaki K Tomono S Kohno 《Canadian Metallurgical Quarterly》1998,72(8):788-793
Toxic shock syndrome toxin-1 (TSST-1) and enterotoxins are important virulence factors produced by Staphylococcus aureus. It is reported that these toxins are associated with septic shock and toxic shock syndrome. We investigated the toxin production and coagulase types of 701 MRSA strains isolated in Sasebo City General Hospital between 1994 and 1996 TSST-1 or/and enterotoxins were detected in 67% of all MRSA strains, and those were detected in 88% of MRSA strains isolated from blood samples. 45% of all MRSA strains produced both TSST-1 and enterotoxin C, and 70% of MRSA strains obtained from blood produced those toxins. Frequency of TSST-1 or/and enterotoxin production by MRSA strains isolated from blood samples was significantly higher than that by MRSA strains isolated from urine and pharynx (p < 0.05), and frequency of both TSST-1 and enterotoxin C production by MRSA isolates from blood was significantly higher than that by MRSA strains isolated from pharyngeal sample (p < 0.05). This study indicated that investigation of virulence factors produced by MRSA might give the useful information on prevention and treatment of MRSA infection. 相似文献
105.
Hitoshi Kubota Noriyasu Nagaoka Ryoichi Katakai Masaru Yoshida Hideki Omichi Yasuo Hata 《应用聚合物科学杂志》1994,51(5):925-929
Photografting of N-isopropylacrylamide (NIPAAm) on ethylene–vinyl alcohol copolymer films (thickness = 15,20, and 25 μm) and low-and high-density polyethylene films (thickness = 30 μm) was carried out at 60°C in a water medium. Xanthone was used as a photoinitiator by coating it on the film samples. The resultant NIPAAm-grafted films exhibited a temperature-responsive character, which was evaluated by measuring a dimensional change of the grafted films. The grafted films swelled and shrank in water at temperatures lower and higher than around 30°C, respectively. The character was found to be reversible between 0 and 50°C. It was observed that the extent of the character is largely influenced by film thickness, location of NIPAAm-grafted chains, and crystallinity of film substrate. © 1994 John Wiley & Sons, Inc. 相似文献
106.
Kiyoshi Dowaki Shunsuke Mori Chihiro Fukushima Noriyasu Asai 《Electrical Engineering in Japan》2005,153(3):52-63
This paper presents a comprehensive economic analysis of biomass gasification systems. There has recently been interest in promoting biomass energy systems in Japan's domestic sector. However, there are problems in achieving this project. The costs of plant construction are very high compared with conventional plants. Accordingly, the unit costs of electricity will be increased to levels comparable with those of other environmental energy systems. Copyright © 2004 Wiley Periodicals, Inc. In this paper, biomass energy systems using woody biomass are proposed from the viewpoint of successful environmental business. Biomass integrated gasification combined cycle (BIGCC) plants operated by independent power producers and biomass gasification cogeneration (BGCGS) plants in sawmills or asphalt‐concrete production factories have the potential for implementation in the near future. Our analysis concludes that the systems proposed in this paper provide the following outcomes with subsidies: (1) the generating cost of BIGCC ranges from 15.1 to 36.6 yen/kWh, (2) the generating cost of BGCGS ranges from 2.6 to 32.2 yen/kWh, and (3) the cost reduction of BGCGS products in asphalt factories amounts to about 60 million yen per year. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 153(3): 52–63, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20089 相似文献
107.
K Yamada S Kanba S Anamizu K Ohnishi I Ashikari G Yagi M Asai 《Canadian Metallurgical Quarterly》1997,27(5):1223-1225
BACKGROUND: Tardive dyskinesia (TD) is a therapy-resistant adverse effect of neuroleptics. Although the exact pathophysiology of TD is unknown, oxygen radicals have been speculated to play a role in TD based on several lines of evidence. Superoxide dismutase (SOD) is a key enzyme which scavenges oxygen radicals. The authors investigated the association between erythrocyte SOD activity and TD. METHODS: Erythrocyte SOD activities were measured, blinded as to the presence or absence of TD. In 30 patients with schizophrenia who had been on typical neuroleptics for more than 10 years. TD severity was independently assessed, using the abnormal involuntary movement scale (AIMS), by two raters. RESULTS: There was a significant decrease in erythrocyte SOD activity in the definite TD group (N = 10) as compared with the no TD (N = 8) and questionable TD (N = 12) groups. Erythrocyte Cu,Zn-SOD activities correlated with AIMS scores. CONCLUSIONS: Patients with TD had low SOD activities as compared to those without TD. As a causal link between SOD activity and TD was not established in this study, larger prospective studies are warranted to determine whether patients with low SOD activity are susceptible to neuroleptic-induced TD. 相似文献
108.
Y Kanda S Chiba M Kami T Asai Y Tanaka T Saito Y Yazaki H Hirai 《Canadian Metallurgical Quarterly》1998,100(4):798-800
In thermolysin, tryptophan 115 seems to be at the S2 subsite. Trp-115 was replaced with tyrosine, phenylalanine, leucine, and valine during site-directed mutagenesis in order to evaluate the role of Trp-115 in the proteolytic activity of thermolysin. The mutant enzymes with Tyr-115 or Phe-115 had as much proteolytic activity as the wild-type enzyme, but the other two mutant enzymes had no activity. We found earlier that the substitution of Trp-115 with alanine, glutamic acid, lysine, and glutamine causes the enzyme to lose all activity, so an aromatic amino acid at position 115 seems to be essential for thermolysin. 相似文献
109.
Advanced design techniques for GaAs wideband direct-coupled amplifiers are described. The amplifier achieved a 20 dB gain with a 3 dB bandwidth of 13 GHz and a 5-7 dB noise figure. An equalizing amplifier module consisting of amplifier and variable attenuator monolithic microwave integrated circuits (MMICs) exhibited a high gain of 43 dB over a 10 GHz band with a controllable gain of 20-43 dB 相似文献
110.
Study of meniscus behavior and surface properties during casting in a high-frequency magnetic field 总被引:6,自引:0,他引:6
Tingju Li Shinji Nagaya Kensuke Sassa Shigeo Asai 《Metallurgical and Materials Transactions B》1995,26(2):353-359
Surface quality of continuously cast metals can be improved by imposing a continuous high-frequency magnetic field from the
outside of a mold. Newly proposed concepts of “soft contacting solidification” and “slow cooling solidification,” which is
tightly related to the mechanism of improving surface quality, were confirmed in model experiments by using molten gallium
and tin. The meniscus motion of the molten gallium accompanied by a mold oscillation and magnetic pressure was measured by
a laser level sensor. The shape variation of a meniscus and the process of ripple formation in an oscillation cycle were directly
visualized by an optical fiberscope camera. Moreover, molten tin was continuously cast and the relationship between the surface
quality and the meniscus motion was studied. A mechanical model for predicting the space between the oscillation marks is
proposed. The casting process using intermittent highfrequency magnetic field was developed. New functions of this field were
investigated regarding the control of initial solidification. It was found that the surface quality of the continuously cast
metal can be improved by the intermittent high-frequency magnetic field as well as the continuous high-frequency magnetic
field.
Formerly Undergraduate Student, Department of Materials Processing Engineering, Nagoya University, 相似文献