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The cross section for single and pair productions of scalar electrons in e+e- annihilation are calculated in the energy range of TRISTAN, SLC and LEP with specific emphasis on the contribution from the Z0 boson and the zino.  相似文献   
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Three new euglobals with acylphloroglucinol-monoterpene structures, named euglobal -G1 (1), -G2 (2), and -G3 (3) were isolated from the chloroform extract of the juvenile leaves of Eucalyptus grandis (Myrtaceae). The structures of these new compounds were determined on the basis of their spectral data. The compounds strongly inhibited the Epstein-Barr virus activation.  相似文献   
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The reaction of three types of carbon nanofibers (CNFs; platelet: CNF‐P, tubular: CNF‐T, herringbone: CNF‐H) with [Ru3(CO)12] in toluene heated at reflux provided the corresponding CNF‐supported ruthenium nanoparticles, Ru/CNFs (Ru content=1.1–3.8 wt %). TEM studies of these Ru/CNFs revealed that size‐controlled Ru nanoparticles (2–4 nm) exist on the CNFs, and that their location was dependent on the surface nanostructures of the CNFs: on the edge of the graphite layers (CNF‐P), in the tubes and on the surface (CNF‐T), and between the layers and on the edge (CNF‐H). Among these Ru/CNFs, Ru/CNF‐P showed excellent catalytic activity towards hydrogenation of toluene with high reproducibility; the reaction proceeded without leaching of the Ru species, and the catalyst was reusable. The total turnover number of the five recycling experiments for toluene hydrogenation reached over 180 000 (mol toluene) (mol Ru)?1. Ru/CNF‐P was also effective for the hydrogenation of functionalized benzene derivatives and pyridine. Hydrogenolysis of benzylic C? O and C? N bonds has not yet been observed. Use of poly(ethylene glycol)s (PEGs) as a solvent made possible the biphasic catalytic hydrogenation of toluene. After the reaction, the methylcyclohexane formed was separated by decantation without contamination of the ruthenium species and PEG. The insoluble PEG phase containing all of the Ru/CNF was recoverable and reusable as the catalyst without loss of activity.  相似文献   
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In this paper we examined the relations between three classes of people (96 Japanese centenarians, 96 Japanese Alzheimer's disease (AD) patients and 96 Japanese Parkinson's disease (PD) patients) and their mitochondrial single nucleotide polymorphism (mtSNP) frequencies at individual mitochondrial DNA (mtDNA) positions of the entire mt-genome by using the radial basis function (RBF) networks. As a result, we got new findings of mtSNPs for representing characteristics of individual classes. These mtSNPs show distinct differences for three classes of people. That is, individual classes of people are characterized by unique mtSNPs. Interestingly, Japanese centenarians are closely associated with haplogroup D4, Japanese AD patients with haplogroup G2a, and Japanese PD patients with haplogroup M7a. These characteristics of mtSNPs are different from those of previously reported works. As the amino acid replacement mtSNPs were at four mtDNA positions, it is indicated that mtSNPs of synonymous nucleotide substitutions as well as those of nonsynonymous nucleotide substitutions may play important roles in mitochondrial functions.  相似文献   
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Previous results on quasi-classical limit of the KP and Toda hierarchies are now extended to the BKP hierarchy. Basic tools such as the Lax representation, the Baker-Akhiezer function and the tau function are reformulated so as to fit into the analysis of quasi-classical limit. Two subalgebrasW 1 B + andw 1 B + of theW-infinity algebrasW 1 + andw 1 + are introduced as fundamental Lie algebras of the BKP hierarchy and its quasi-classical limit, the dispersionless BKP hierarchy. The quantumW-infinity algebraW 1 B + emerges in symmetries of the BKP hierarchy. In quasi-classical limit, theseW 1 B + symmetries are shown to be contracted intow 1 B + symmetries of the dispersionless BKP hierarchy.  相似文献   
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In this paper singular Cauchy problems of Hamada's type are studied in the category of holomorphic functions and hyperfunctions for a class of hyperbolic differential operators with non-involutive multiple characteristics. Integral representations of their solutions are obtained.  相似文献   
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