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Evolutionary learning techniques are comparable in accuracy with other learning methods such as Bayesian Learning, SVM, etc. These techniques often produce more interpretable knowledge than, e.g. SVM; however, efficiency is a significant drawback. This paper presents a new representation motivated by our observations that Bioinformatics and Systems Biology often give rise to very large-scale datasets that are noisy, ambiguous and usually described by a large number of attributes. The crucial observation is that, in the most successful rules obtained for such datasets, only a few key attributes (from the large number of available ones) are expressed in a rule, hence automatically discovering these few key attributes and only keeping track of them contributes to a substantial speed up by avoiding useless match operations with irrelevant attributes. Thus, in effective terms this procedure is performing a fine-grained feature selection at a rule-wise level, as the key attributes may be different for each learned rule. The representation we propose has been tested within the BioHEL machine learning system, and the experiments performed show that not only the representation has competent learning performance, but that it also manages to reduce considerably the system run-time. That is, the proposed representation is up to 2–3 times faster than state-of-the-art evolutionary learning representations designed specifically for efficiency purposes. 相似文献
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Hermann Ehrlich Manuel Maldonado Andrew R. Parker Yuri N. Kulchin Jrg Schilling Benjamin Khler Ulrich Skrzypczak Paul Simon Henry M. Reiswig Mikhail V. Tsurkan Eike Brunner Sergey S. Voznesenskiy Alexander V. Bezverbny Sergey S. Golik Ivan G. Nagorny Denis V. Vyalikh Anna A. Makarova Serguei L. Molodtsov Kurt Kummer Michael Mertig Christiane Erler Denis V. Kurek Vasilii V. Bazhenov Filipe Natalio Alexander E. Kovalev Stanislav N. Gorb Allison L. Stelling Johannes Heitmann Ren Born Dirk C. Meyer Konstantin R. Tabachnick 《Advanced Optical Materials》2016,4(10):1608-1613
The complex process of supercontinuum generation (SG) is known to be exploitable for designing spatially coherent white light sources emitting light simultaneously in the ultraviolet, visible, and infrared ranges. Herein the first natural material able to generate in laboratory conditions a supercontinuum similar to those known from man‐made photonic crystal fibers is described. The ability resides in siliceous 20–50 cm long spicules of the glass sponge Sericolophus hawaiicus. By shedding into the spicules optical peak intensities ranging from 1 to 100 TW cm−2 the generation of a SG is revealed. The SG involves wavelengths between 650 and 900 nm and shows a maximum spectral spread for excitation at a wavelength of 750 nm. It is hypothesized that the SG is favored by spicules being a biocomposite that incorporates together isotopically pure biogenic silica (δ30Si = −3.28) and 15.2 ± 1.3 μg N‐acetyl‐glucosamine (chitin) per mg of silica. The internal organization of these spicules is distinguished by a solid silica core with a 1 μm wide axial channel as well as a highly ordered silica–chitin composite. Such a composition and organization pattern may be of potential interest for the design of low temperature synthesis of future materials for light guidance. 相似文献
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Rodríguez G Gallardo A Fernández M Rebuelta M Buján J Bellón JM Honduvilla NG Escudero C San Román J 《Macromolecular bioscience》2004,4(6):579-586
Hydrophilic polymeric drugs bearing \"Triflusal\" (4-trifluoromethylsalicylic acid), a drug widely used as antithrombogenic agent (Disgren), have been prepared by free radical copolymerization of methacryloyloxyethyl [2-(acetyloxy)-4-(trifluoromethyl)] benzoate (HTRF) and N,N'-dimethylacrylamide (DMA). The reactivity ratios of both monomers have been determined by 1H NMR spectra by applying non-linear least square treatments to the copolymerization equation (terminal model), and the kinetic parameters obtained indicated that the microstructure of copolymer chains is homogeneous, with a random distribution of the active HTRF units along the copolymer chains. That means that for the copolymer system THDMA22 used in this work, HTRF units are mainly isolated in relatively long DMA sequences. Therefore, in this structure the intramolecular interactions between adjacent HTRF units are negligible. Release of Triflusal from THDMA22 has been studied in vitro using buffered solutions at pH = 2, 7.4 and 10 and 37 degrees C. The system showed an interesting pseudo-zero order release profile at pH = 7.4 during several months. It has been also evaluated the pharmacological activity and the behavior of the system in contact with biological media. In this sense, we have carried out some in vitro studies about the antiaggregant properties and biocompatibility of THDMA22. Results demonstrate that this copolymer inhibits platelet aggregation in its macromolecular form and presents a good biocompatibility with Human Osteoblastic Cells (HOS). 相似文献
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Thomas D. Schladt Mohammed Ibrahim Shukoor Dr. Kerstin Schneider Muhammad Nawaz Tahir Dr. Filipe Natalio Irene Ament Jan Becker Florian D. Jochum Stefan Weber Oskar Köhler Patrick Theato Dr. Laura Maria Schreiber Prof. Dr. Carsten Sönnichsen Prof. Dr. Heinz C. Schröder Prof. Dr. Dr. Werner E. G. Müller Prof. Dr. Wolfgang Tremel Prof. Dr. 《Angewandte Chemie (International ed. in English)》2010,49(23):3976-3980
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