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Nemenchinskaya Ekaterina O. Kondratenko Yuri V. Sadovsky Michael G. 《Open Systems & Information Dynamics》2004,11(2):161-175
The new method of a gap recovery in symbol sequences is presented. A covering is combined from the suitable reasonably short strings of the parts of a sequence available for observation. Two criteria are introduced to choose the best covering. It must yield the maximum of entropy of a frequency dictionary developed over the sequence obtained due to the recovery, if an overlapping combined from the copies of strings from the available parts of the sequence exists. The second criterion identifies the best covering in case when one has to use any string to cover the gap; here the best covering must yield the minimum of specific entropy of the frequency dictionary developed over the available parts of the sequence against the one developed over the entire sequence obtained due to the recovery. Kirdin kinetic machine which is the ideal fine-grained structureless computer has been used to resolve the problem of the reconstruction of a gap in symbol sequence. 相似文献
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EY Anteby RD Johnson X Huang DM Nelson Y Sadovsky 《Canadian Metallurgical Quarterly》1997,82(7):2289-2293
Abnormal PG production by placental PG-H synthase (PGHS) is associated with preeclampsia. There are two PGHS isozymes, and their regulation in trophoblasts is presently unknown. We hypothesized that the PGHS isozymes are differentially regulated in human trophoblasts. To test this hypothesis, we transfected primary trophoblasts and JEG3 cells with promoter constructs of either PGHS-1 or PGHS-2 genes. We found that in both cell systems, the basal activity of PGHS-2 promoter was 10- to 30-fold higher than the activity of PGHS-1 promoter. In response to either 12-0-tetradecanoylphorbol-13-acetate (TPA) or 8-bromo-cAMP, we observed an increase in PGHS-2 promoter activity but no change in activity of PGHS-1 promoter. Similarly, both agents enhanced PGHS-2 expression, as well as prostaglandin E2 production. The activity of PGHS-2 promoter was potentiated by coexpression of protein kinase A and inhibited by coexpression of kinase A inhibitor. Aspirin attenuated the stimulatory effect of TPA on PGHS-2 promoter. We conclude that both PGHS-1 and PGHS-2 promoters are active in trophoblasts. The activity of PGHS-2 promoter is stimulated by either TPA or cAMP, and the stimulatory effect of TPA is attenuated by aspirin. These pathways may play a role in modulation of prostanoid synthesis by trophoblasts. 相似文献
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Eisenberg Nancy; Sadovsky Adrienne; Spinrad Tracy L.; Fabes Richard A.; Losoya Sandra H.; Valiente Carlos; Reiser Mark; Cumberland Amanda; Shepard Stephanie A. 《Canadian Metallurgical Quarterly》2005,41(1):193
The relations of children's internalizing and externalizing problem behaviors to their concurrent regulation, impulsivity (reactive undercontrol), anger, sadness, and fearfulness and these aspects of functioning 2 years prior were examined. Parents and teachers completed measures of children's (N = 185; ages 6 through 9 years) adjustment, negative emotionality, regulation, and behavior control; behavioral measures of regulation also were obtained. In general, both internalizing and externalizing problems were associated with negative emotionality. Externalizers were low in effortful regulation and high in impulsivity, whereas internalizers, compared with nondisordered children, were low in impulsivity but not effortful control. Moreover, indices of negative emotionality, regulation, and impulsivity with the level of the same variables 2 years before controlled predicted stability versus change in problem behavior status. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Highly oriented gel‐spun ultrahigh molecular weight polyethylene (UHMWPE) fibers possess many outstanding properties desirable for composite materials but their adhesion to such matrices as epoxy is poor. This article describes the combined effects of drawing and surface modification on the bulk and surface properties of gel‐cast UHMWPE films emphasizing the effects of etching on both undrawn and drawn films. Drawing the films yields a fibrillar structural hierarchy similar to UHMWPE fibers and a significant increase in orientation, melting point, modulus, and strength. The effects of drawing on bulk properties were more significant than those of etching. The poor adhesion of epoxy to the smooth, fibrillar, and relatively nonpolar drawn film surface improves significantly with oxidization and roughening on etching. The interlaminar shear failure occurred cohesively in the UHMWPE, and thus the interlaminar shear failure strength was greater for the drawn UHMWPE with its greater tensile strength. Nitrogen plasma etching yielded the best results, both removing any low molecular weight surface layer and etching the UHMWPE beneath. Oxygen plasma etching enhanced wetting but was too harsh, causing extensive surface degradation and a significant reduction in mechanical properties. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 405–418, 1999 相似文献
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A Charged-Particle Detector Based on Proportional Tubes with a Segmented Cathode and Cathode Readout
A. M. Blick M. Yu. Bogolyubsky S. V. Erin M. O. Lobanov N. G. Minaev S. A. Sadovsky V. D. Samoilenko V. I. Suzdalev V. V. Tikhonov Yu. V. Kharlov A. Di Mauro P. Martinengo F. Piuz J. Van Beelen D. Williams M. S. Ippolitov Yu. G. Sibiryak M. A. Volkov A. Klovning O. A. Maeland O. H. Odland R. Rongved B. Skaali 《Instruments and Experimental Techniques》2001,44(3):339-346
A charged-particle detector based on proportional tubes with cathode readout is described. The cathode is sectionalized into 2.2 × 2.2-cm pads. The detector was tested on high-energy particle beams. At an anode-to-cathode distance of 1.1 cm, the spatial resolution was 1.25 mm along the anode wire. A simulation model of the detector on the basis of the measured pad-response function was proposed, compared to the experimental data, and used to calculate the two-track resolution. The detector can be used in various experiments as a large-area multiparticle two-coordinate detector. 相似文献
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V.M. Golovatyuk Z. Guzik R.B. Kadyrov T.S. Nigmanov V.D. Riabtsov A.B. Sadovsky A.E. Senner M.D. Shafranov E. Streit V.G. Timofeev E.N. Tsyganov I.A. Tyapkin A.S. Vodopianov J. Wojtkowska N.I. Zimin 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,236(2):300-306
The operating characteristics of plastic streamer tubes chosen as a detector of the DELPHI-LEP hadron calorimeter are described. The work has been performed using a set-up specially designed to investigate a hadron calorimeter prototype on a beam of the Dubna synchrophasotron. The apparatus operated on-line with an ES-1040 computer. 相似文献
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The classifications of bacterial 16S RNA sequences developed over the real and transformed frequency dictionaries have been studied. Two sequences are considered to be close, when their frequency dictionaries are close in Euclidean metrics. A procedure to transform a dictionary is proposed that makes clear some features of the information pattern of a symbol sequence. A comparative study of classifications developed over real frequency dictionaries vs. the transformed ones has been carried out. A correlation between information patterns of nucleotide sequences and taxonomy of the bearer of the sequence was found. The sites with high information value are found to be the main factors of the difference between the classes in a classification. The classification of nucleotide sequences developed over real frequency dictionaries of thickness 3 reveals the best correlation to a gender of bacteria. A set of sequences of the same gender is included entirely into one class, as a rule, and exclusions occur rarely. A hierarchical classification yields one or two taxonomy groups on each level of classification. An unexpectedly often, or unexpectedly rare occurrence of some sites within a sequence makes a basic difference between the structure patterns of the classes yielded; a number of those sites is not to large. Further investigations are necessary in order to campare the sites revealed with those determined due to other methodology. 相似文献