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Machine Learning - Graphs are versatile tools for representing structured data. As a result, a variety of machine learning methods have been studied for graph data analysis. Although many such... 相似文献
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Takeo Uchida Keita Abe Yuma Endo Shosei Ichiseki Satoru Akita Shiyun Liu Sho Aradachi Masataka Saito Akihiko Fukuchi Taiyo Kikkawa Theo Dammaretz Ibuki Kawamata Yuki Suzuki Shin‐ichiro M. Nomura Satoshi Murata 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(41)
A new kind of the Vernier mechanism that is able to control the size of linear assembly of DNA origami nanostructures is proposed. The mechanism is realized by mechanical design of DNA origami, which consists of a hollow cylinder and a rotatable shaft in it connected through the same scaffold. This nanostructure stacks with each other by the shape complementarity at its top and bottom surfaces of the cylinder, while the number of stacking is limited by twisting angle of the shaft. Experiments have shown that the size distribution of multimeric assembly of the origami depends on the twisting angle of the shaft; the average lengths of the multimer are decamer, hexamer, and tetramer for 0°, 10°, and 20° twist, respectively. In summary, it is possible to affect the number of polymerization by adjusting the precise shape and movability of a molecular structure. 相似文献
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H Akita Y Sato Y Kusumoto S Iwata Y Takeuchi T Aoyama T Yokota K Sunakawa 《Canadian Metallurgical Quarterly》1996,49(10):899-916
Azithromycin (AZM), a new macrolide antibiotic, in fine granules and in capsules was studied for pharmacokinetic and clinical evaluation in the pediatric patients. Antibacterial activity of AZM against 43 clinical isolates: AZM exhibited slightly lower activity against Gram-positive bacteria and 2-8-fold higher activity against Gram-negative bacteria than erythromycin or clarithromycin. Plasma or urine samples were collected from eight patients receiving the drug in fine granular form, and two patients receiving it in capsules for the determination of drug levels. The elimination half-lives of AZM after administration at dose of 10 mg/kg/day for 3 days were 50.0 and 51.2 hours for fine granules, and 41.5 hours for capsules. AUC0-infinity was 11.7 and 24.3 micrograms.hr/ml for fine granules, and 8.3 micrograms.hr/ml for capsules. The cumulative excretion rates up to 120 hours after the start of treatment were 8.24 and 13.84% for fine granules, and 3.83% for capsules. AZM was administered to 123 patients once daily at 3.7-20.0 mg/kg body weight over 3 to 5 days with reference to the standard dose of 10 mg/kg. The drug was used to treat patients with pharyngitis, tonsillitis, scarlet fever, pneumonia, mycoplasmal pneumonia, chlamydial pneumonia, otitis media, pertussis, intestinal infection, and SSTI. The effectiveness of AZM was evaluated in 109 cases. The drug was rated "excellent" in 65.1% of the patients and "good" in 29.4%, resulting in an efficacy rate of 94.5%. Furthermore, AZM eradicated 43 of 46 (93.5%) bacteria that had been identified before the treatment. Three patients complained of side effects of urticaria (1 case) and diarrhea (2 cases). Abnormal laboratory changes were reported as follows: decreased leukocyte (3 cases), increased eosinophil (5), increased platelet (2), increased eosinophil and platelet, elevated GPT (1), and elevated GOT and GPT (1). The abnormalities, however, were mild enough to raise no clinically significant problems. In conclusion, AZM in once daily regimen was effective and safe in treatment of pediatric infections. 相似文献
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Keiji Hayashi Tomoki Shiraishi Kazuho Toyoda Fumiya Tanaka Taiga Mori Takumi Hata 《Computer Physics Communications》2011,(9):2032-2035
Laws of dynamic nano-friction (i.e., continuous wearless friction) were searched for under steady spatial distributions of the local quasi-temperature, by molecular dynamics (MD) simulations. The temperature control of the non-conservative model was carried out by extending the isothermal MD method using the Nosé–Poincaré thermostat. The results suggested that the threshold phenomenon characterizes sliding-velocity dependence of the nano-frictional force between crystal lattices constituting a nano-electromechanical system (NEMS). This phenomenon was turned out to be a universal feature, whether heat transfer to the environment exists or not. 相似文献
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Huimin Lu Yujie Li Tomoki Uemura Zongyuan Ge Xing Xu Li He Seiichi Serikawa Hyoungseop Kim 《Multimedia Tools and Applications》2018,77(17):21847-21860
Convolutional networks are currently the most popular computer vision methods for a wide variety of applications in multimedia research fields. Most recent methods have focused on solving problems with natural images and usually use a training database, such as Imagenet or Openimage, to detect the characteristics of the objects. However, in practical applications, training samples are difficult to acquire. In this study, we develop a powerful approach that can accurately learn marine organisms. The proposed filtering deep convolutional network (FDCNet) classifies deep-sea objects better than state-of-the-art classification methods, such as AlexNet, GoogLeNet, ResNet50, and ResNet101. The classification accuracy of the proposed FDCNet method is 1.8%, 2.9%, 2.0%, and 1.0% better than AlexNet, GooLeNet, ResNet50, and ResNet101, respectively. In addition, we have built the first marine organism database, Kyutech10K, with seven categories (i.e., shrimp, squid, crab, shark, sea urchin, manganese, and sand). 相似文献
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Shinya Higashimoto Kohei Okada Tomoki Morisugi Masashi Azuma Hiroyoshi Ohue Tae-Ho Kim Masaya Matsuoka Masakazu Anpo 《Topics in Catalysis》2010,53(7-10):578-583
The photocatalytic oxidation of benzyl alcohol into benzaldehyde proceeded with high conversion and selectivity on a TiO2 photocatalyst by O2 under visible light irradiation. Surface complex formed by the interaction of benzyl alcohol with the Ti sites and/or surface OH groups of TiO2 play an important role in the absorption of visible light and unique selective photocatalytic reaction. 相似文献
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A detailed analysis has been carried out on the deasphaltened Cold Lake bitumen using two different series of chromatographic separations followed by i.r., u.v., n.m.r. and computerized GC/MS studies of the separated fractions: saturates (21.3), monoaromatics (8.3), diaromatics (3.6), polyaromatics and non-specific polar compounds (24.35), acids (15.2), bases (6.38), and neutral nitrogen compounds (1.15% of bitumen). The acyclic paraffin content of the maltene is low but decidedly higher than in the related Athabasca bitumen, indicating that the Cold Lake bitumen suffered a less complete biodegradation. Straight-chain paraffins and the isoprenoids phytane and pristane are present. The mono- and diaromatic fractions were analysed by high-voltage, low-resolution mass spectrometry. The monoaromatic fraction contains alkylbenzenes, naphthenebenzenes and dinaphthenebenzenes in a ratio of approximately 1:1:1. The ratio for naphthalenes, acenaphthenes + dibenzofurans and fluorenes in the diaromatic fraction is approximately 1:0.9:0.6. The composition of Cold Lake bitumen closely resembles that of the Athabasca bitumen except that its asphaltene content is somewhat lower and its acidic and saturate content is slightly higher. 相似文献
10.
Preparation of porous carbons from thermoplastic precursors and their performance for electric double layer capacitors 总被引:2,自引:0,他引:2
Porous carbons with high surface area were successfully prepared from thermoplastic precursors, such as poly(vinyl alcohol) (PVA), hydroxyl propyl cellulose and poly(ethylene terephthalate), by the carbonization of a mixture with MgO at 900 °C in an inert atmosphere. After carbonization the MgO was dissolved out using a diluted sulfuric acid and the carbons formed were isolated. The mixing of the PVA carbon precursor with the MgO precursors (reagent grade MgO, magnesium acetate or citrate) was done either in powder form or in an aqueous solution. The BET surface area of the carbons obtained via solution mixing could reach a very high value, such as 2000 m2/g, without any activation process. The pore structure of the resultant carbons was found to depend strongly on the mixing method; the carbons prepared via solution mixing were rich in mesopores, but those produced via powder mixing were rich in micropores. The size of mesopores was found to be almost the same as that of the MgO particles, suggesting a way of controlling the mesopore size in the resultant carbons. Measurement of capacitance was carried out in 1 mol/L H2SO4 electrolyte. The porous carbon with a BET surface area of 1900 m2/g prepared at 900 °C through solution mixing of Mg acetate with PVA showed a fairly high EDLC capacitance, about 250 F/g with a current density of 20 mA/g and 210 F/g with 1000 mA/g. The rate performance was closely related to the mesoporous surface area. 相似文献