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The problem of finding a variable ordering to minimise the size of a reduced ordered binary decision diagrams (ROBDD) is considered for functions possessing disjunctive decompositions. An example is presented showing that the best ordering for a function with a disjunctive decomposition cannot always be directly determined from the best orderings for the component functions 相似文献
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NA Brazhenko ZI Kostina IuE Godes LL Krokhaleva ON Brazhenko OI Tsareva NM Balashova 《Canadian Metallurgical Quarterly》1998,114(5):48-51
AIM: The study of the detection rate and potential pathogenetic significance of antibodies to low density oxidated lipoprotein (LDOL) in patients who had ischemic cerebral circulation disorder (ICCD) at young age. MATERIALS AND METHODS: The examination (enzyme immunoassay, general and neurological investigations, laboratory and instrumental tests) covered 148 patients who survived ICCD at young age (mean age 37.2 years). RESULTS: 48 of 108 (44%) patients had LDOL antibodies. Antibodies to cardiolipin, lupus anticoagulant were recorded in 33 (31%) patients. LDOL antibodies were higher and occurred more frequently in patients with Sneddon's syndrome (35% of patients, mean LDOL antibodies-44 units) and primary antiphospholipid syndrome (17% of patients, 45 units) than in atherosclerotic affection of the major head arteries (4%, 29 units) or occlusion of cerebral arteries of unclear genesis (8% of patients, 29 units). CONCLUSION: ICCD were not related to fast development of cerebral atherosclerosis or periaortitis due to production of LDOL antibodies as no relationships were found between their rise and atherosclerotic lesions of cerebral major arteries or periaortitis as shown by ultrasonic dopplerography or cerebral angiography. Feasibility of LDOL antibodies participation in the coagulation cascade and induction of hypercoagulatory condition causing ICCD needs special investigation. 相似文献
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YE Dubrova VN Nesterov NG Krouchinsky VA Ostapenko G Vergnaud F Giraudeau J Buard AJ Jeffreys 《Canadian Metallurgical Quarterly》1997,381(2):267-278
Analysis of germline mutation rate at human minisatellites among children born in areas of the Mogilev district of Belarus heavily polluted after the Chernobyl accident has been extended, both by recruiting more families from the affected region and by using five additional minisatellite probes, including multi-locus probe 33.6 and four hypervariable single-locus probes. These additional data confirmed a twofold higher mutation rate in exposed families compared with non-irradiated families from the United Kingdom. An elevated rate was seen at all three independent sets of minisatellites (detected separately by multi-locus probes 33.15, 33.6 and six single-locus probes), indicating a generalised increase in minisatellite germline mutation rate in the Belarus families. Within the Belarus cohort, mutation rate was significantly greater in families with higher parental radiation dose estimated for chronic external and internal exposure to caesium-137, consistent with radiation induction of germline mutation. The spectra of mutation seen in the unexposed and exposed families were indistinguishable, suggesting that increased mutation observed over multiple loci arises indirectly by some mechanism that enhances spontaneous minisatellite mutation. 相似文献
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The ultrastructure of muscle fibres, membrane electrical constants and synaptic membrane responses to microapplication of l-glutamate were investigated in longitudinal flight muscle and flexor tibia of Locusta migratoria migratorioides. The sarcomers of the flight muscle (fast) were smaller then those of the leg muscle (slow). The effective resistances (Ro) of the flight and leg muscles were (2.25 +/- 0.54)-10(5) omega and (1.65 +/- 0.57) X 10(5) omega. The specific resistance (Rm), space constant (tau) and time constant (lambda) in the same muscles were 774 +/- 106 omega-cm and 2583 +/- 119 omega-cm-2; 7.3 +/- 1.7 ms and 17.5 +/- 1.1 ms; 093 +/- 0.22 mm and 1.98 +/- 0.42 mm. When l-glutamate was applied iontophoretically to muscle fibres depolarization was recorded only in localized parts of the membrane. Microapplication of acetylcholine to intact and denervated muscle fibres of the slow leg muscle was uneffective. It is suggested that l-glutamic acid is the excitatory transmitter both in slow and fast insect muscles. 相似文献
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The yeast Saccharomyces cerevisiae mRNA capping enzyme is composed of two subunits of alpha (52 kDa, mRNA guanylyltransferase) and beta (80 kDa, RNA 5'-triphosphatase). We have isolated the alpha subunit gene (CEG1) by immunological screening. In this report, with the aid of partial amino acid sequences of purified yeast capping enzyme, we isolated the gene, designated CET1, encoding the S. cerevisiae capping enzyme beta subunit. Amino acid sequence analysis revealed that the gene encodes for 549 amino acids with a calculated M(r) of 61,800 which is unexpectedly smaller than the size estimated by SDS-PAGE. Gene disruption experiment showed that CET1 is essential for yeast cell growth. The purified recombinant CET1 gene product, Cet1, exhibited an RNA 5'-triphosphatase activity which specifically removed the gamma-phosphate from the triphosphate-terminated RNA substrate, but not from nucleoside triphosphates, confirming the identity of the gene. Interaction between the Cet1 and the Ceg1 was also studied by the West-Western procedure using recombinant Ceg1-[32P]GMP as probe. 相似文献
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Elena Dubrova Mats Näslund Gunnar Carlsson John Fornehed Ben Smeets 《Journal of Signal Processing Systems》2017,87(3):371-381
The threat of hardware Trojans has been widely recognized by academia, industry, and government agencies. A Trojan can compromise security of a system in spite of cryptographic protection. The damage caused by a Trojan may not be limited to a business or reputation, but could have a severe impact on public safety, national economy, or national security. An extremely stealthy way of implementing hardware Trojans has been presented by Becker et al. at CHES’2012. Their work have shown that it is possible to inject a Trojan in a random number generator compliant with FIPS 140-2 and NIST SP800-90 standards by exploiting non-zero aliasing probability of Logic Built-In-Self-Test (LBIST). In this paper, we present two methods for modifying LBIST to prevent such an attack. The first method makes test patterns dependent on a configurable key which is programed into a chip after the manufacturing stage. The second method uses a remote test management system which can execute LBIST using a different set of test patterns at each test cycle. 相似文献
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AJ Jeffreys P Bois J Buard A Collick Y Dubrova CR Hollies CA May J Murray DL Neil R Neumann JD Stead K Tamaki J Yardley 《Canadian Metallurgical Quarterly》1997,18(9):1501-1511
Minisatellites provide not only the basis for DNA fingerprinting and DNA profiling but also extremely informative systems for analysing processes of tandem repeat turnover in the human genome. Minisatellite instability appears to involve distinct mutation processes in somatic and germline cells; in the germline, mutation is frequently dominated by inter-allelic conversion-like events most likely occurring at meiosis and apparently regulated by cis-acting mutation initiator elements. Attempts to define these initiators in transgenic mice have so far been thwarted by what appears to be a major human/mouse barrier to the inter-species transfer of repeat instability. Minisatellites not only show high frequency spontaneous mutation in the germline, but also appear to be very sensitive to mutation induction by ionizing radiation, both in experimentally irradiated mice and in human populations exposed following the Chernobyl disaster; the mechanisms of mutation induction by radiation remain enigmatic. 相似文献