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991.
Speculations about the role of consciousness in physical systems are frequently observed in the literature concerned with the interpretation of quantum mechanics. While only three experimental investigations can be found on this topic in physics journals, more than 800 relevant experiments have been reported in the literature of parapsychology. A well-defined body of empirical evidence from this domain was reviewed using meta-analytic techniques to assess methodological quality and overall effect size. Results showed effects conforming to chance expectation in control conditions and unequivocal non-chance effects in experimental conditions. This quantitative literature review agrees with the findings of two earlier reviews, suggesting the existence of some form of consciousness-related anomaly in random physical systems. 相似文献
992.
This study was conducted to compare the relative performance of 19 univariate EEG power distribution parameters in terms of their sensitivity to changes in the background (stationary) EEG activity and insensitivity to broad-band interference. Each of the parameters partitioned the power spectrum into two frequency subbands, each subband containing a fixed specific percentage of the total power. The EEG signals recorded from ten patients during induction with thiopental sodium were used in the study. Two sensitivity functions were defined to compare the sensitivity of the parameters to the effects of thiopental sodium. Parameter changes were compared to bandwidth changes during induction to evaluate their sensitivity to broad-band interference. The results of the study showed that the parameters in the middle of the percentile scale were more sensitive to background EEG changes produced by thiopental sodium than were those at either end of the scale. Sensitivity to broad-band interference was found to be directly proportional to percentile. Within the limits of this study, a parameter between the 25th and 30th percentiles would be the most suitable parameter to monitor intraoperatively. 相似文献
993.
Products of the reaction of OH radicals with 1-butene have been investigated in the presence of NO in one atmosphere of air at room temperature using gas chromatography and in situ long pathlength Fourier transform infrared absorption spectroscopy. The major product observed was propionaldehyde, with a formation yield (after allowing for its subsequent loss processes) of 0.94 ± 0.12. Minor yields of organic nitrates (RONO2) and of peroxypropionyl nitrate, a secondary product arising from propionaldehyde, were also observed. However, none of the products expected from the reactions subsequent to H-atom abstraction from 1-butene by OH radicals were observed, allowing an upper limit of 10% for this process to be derived. These data are compared with the available literature results and the implications are discussed. 相似文献
994.
A fast, sensitive sandwich fluorimmunoassay for hepatitis B surface antigen (HBs-ag) is described. Rabbit antibodies to HBs-ag are covalently bound to the centre of a glass-fiber filter disk. The second antibody is a swine anti-human HBs-ag conjugated with β-d-galactosidase from E. coli. The substrate is 4-methylumbelliferyl-β-d-galactopyrano-side. The technique is applied with the Stratus system which does the entire test in 8 min. the detection limit is 1 ng ml?1, and the results correlate well with a radioimmunoassay technique. 相似文献
995.
Experimental and theoretical results on the helix-coil transition of DNA are reviewed. The theoretical model of the transition is described, and the influence of heterogeneous base pair stacking, and strand dissociation on the predicted melting transition is examined. New experimental transition data on seven DNAs, 154–587 base pairs (bp) long, are reported and compared with theoretical calculations. We review and evaluate previous studies on long DNAs (≥1000 bp) as well as previous and recent results on short DNAs. The comparison of theory with equilibrium melting curves of short DNAs indicates that base pair sequence has a relatively small influence on the stacking free energy. Excellent agreement is obtained between theory and equilibrium transitions of 14 out of 15 fragments 80–587 pb. The deviation between theory and experiment for a 516 bp DNA can be attributed to the formation of stem-loop structures. This may provide the explanation for inconsistent results observed with long DNAs. The effect of single base pair changes on DNA transitions is discussed. Current views on fluctuational opening of base pairs at temperatures below the transition are described. 相似文献
996.
The emerging interactive video dial tone (VDT) services pose some unique requirements for real-time network monitoring and control. To support the roll-out of VDT-based networks and services, GTE is developing new network management applications on its TONICS (Telephone Operations Network Integrated Control System) platform. TONICS's applications are embedded in a high availability software platform providing distributed processing. The article describes the real-time management requirements of VDT networks, provides an overview of the TONICS integration platform, outlines a network management and control architecture for VDT networks, illustrates example VDT management applications, and discusses the deployment issues 相似文献
997.
D.M. Malon (ibid., vol. 38, p.275-6, Aug. 1989) points out a pitfall of certain reliability problems pertaining to systems of three-state devices. The inference to be drawn from his observation is that special care should be used in describing such systems and in specifying exactly what constitutes success and failure. The present authors (ibid., vol.37, p.388-94, Oct. 1988) have modeled systems that can be represented by a network with designated source and sink; the reliability problem they treated is described by the following two system failures: (1) the system fails (short) if there is a path of short-failed components joining the source and the sink; (2) the system fails (open) if every path joining the source and sink includes an open-failed component. The systems they modeled are therefore somewhat more general then the array structures treated by B.W. Jenney and D.J. Sherwin (ibid., vol.R-35, p.532-8, Dec. 1986). But since the two failure-modes are mutually exclusive, the pitfall that Malon describes does not affect the former. Jenney and Sherwin's difficulties do not arise because of the generality of the systems; rather, they appear in some of the more general reliability measures (such as j -out-of-m requirements) used on the sp-arrays and ps-arrays 相似文献
998.
Roger L. Jones 《Proceedings of the American Mathematical Society》2004,132(4):1087-1090
We give a new (shorter) proof of a result of L. Ephremidze showing that if two functions have the same ergodic maximal function, then they are equal a.e.
999.
A review of the merits of Mössbauer spectroscopy in the study of magnetic materials is given with special emphasis on the results obtained for57Fe. Although the Mössbauer method can, in some cases, give unique information also in this area of research, the combination with other experimental methods such as the thermomagnetic ones and neutron diffraction is essential.
相似文献1000.