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821.
J Boomker DG Booyse R Watermeyer IL De Villiers IG Horak JR Flamand 《Canadian Metallurgical Quarterly》1996,63(4):265-271
Reliability of event-related P3 parameters. Various parameters of the P3 wave were tested for reliability and test-retest stability. To this end, event-related P3 waves were evoked in 21 subjects during visual and auditory oddball tasks. The protocol was repeated one to two weeks later. Amplitude, latency and area between P3 and baseline were estimated by different procedures. The stability within and between sessions was assessed with the split-half method and a measure of test-retest reliability, respectively. A literature review revealed that latency estimation is most commonly done by computer-aided peak measurement, but determining peak parameters visually after interpellating superimposed artifacts turned out to be significantly more reliable. Interrater reliability for this visual inspection was very high if preestablished rules were employed. Amplitude and area were measured reliably by both computer-aided procedures and visual inspection. The area was quite stable both within and between sessions. Area can serve as a measure of cerebral activation and should therefore be determined. Based on the results recommendations are made about analyzing components of event-related potentials. The need to control for error variance is emphasized. This is the only way to improve methods enough that they will be suitable for use in single case diagnosis. 相似文献
822.
The literature on gas-evolving electrodes is reviewed. Cell voltage measurements are reported for an undivided cell in NaOH at 70° C in which the cathode was mild steel plate, mild steel mesh or composites of both these materials. The anode was Ni-plated mild steel sheet or mesh. Variation in the structure of one electrode, leaving the other unchanged allowed changes in overvoltage to be measured. It is shown that substantial voltage reductions can be obtained using multiplex electrode structures and that these are mainly explicable in terms of specific surface areas. Sheet electrodes are seen to be more efficient than mesh ones on this basis however. It is shown that sheet electrodes with very high specific surface areas show significantly higher overvoltages than electrodes of low specific area and this surprising result is interpreted in terms of bubble entrapment. 相似文献
823.
In the Presidential Address at the meeting of the Canadian Psychological Association, Winnipeg, June, 1983 the author examines the relationship between psychology and the other behavioral sciences and several areas of technological change, particularly those involving computer science and information processing and advances in health technology. Specifically, the social impact of technological change and the role of psychology in the planning for, and the implementation and evaluation of, the effects of technological change are stressed. Human primacy is proposed as an alternative to technological primacy in the development of societal goals. Recommendations are offered for action, including the establishment of a national institute to focus on the area of the impact on humanity of the technological revolution. (French abstract) (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
824.
A competitive enzyme linked immunosorbent assay with antigen immobilized on the solid phase was developed to measure alpha 2-macroglobulin in rat serum. The cross reactivity with albumin and hemoglobin was eliminated by use of IgG fractions that were isolated after chromatography on Cibacron Blue F3-GA Sepharose immobilized rat whole serum and hemoglobin Sepharose. Blocking materials and pH of the coating buffer had no effect on the amount of alpha 2-macroglobulin that binds to the plate. When the coating amount of alpha 2-macroglobulin was 100 ng/well, at pH 7.4, 10 mM Tris-HCl containing 150 mM sodium chloride and the IgG amount added was 60 ng/well, then albumin and hemoglobin did not affect the assay at concentrations of 150 micrograms/ml or 200 micrograms/ml. This assay is useful for measuring the concentration of alpha 2-macroglobulin in normal and irradiated rat serum. 相似文献
825.
826.
J. Heinrich J. Vuong C. J. Hammang A. Wu M. Rittenbruch J. Hogan M. Brereton S. I. O'Donoghue 《Computer Graphics Forum》2016,35(3):181-190
While many measures of viewpoint goodness have been proposed in computer graphics, none have been evaluated for ribbon representations of protein secondary structure. To fill this gap, we conducted a user study on Amazon's Mechanical Turk platform, collecting human viewpoint preferences from 65 participants for 4 representative superfamilies of protein domains. In particular, we evaluated viewpoint entropy, which was previously shown to be a good predictor for human viewpoint preference of other, mostly non‐abstract objects. In a second study, we asked 7 experts in molecular biology to find the best viewpoint of the same protein domains and compared their choices with viewpoint entropy. Our results indicate that viewpoint entropy overall is a significant predictor of human viewpoint preference for ribbon representations of protein secondary structure. However, the accuracy depends on the type and composition of the structure: while most participants agree on good viewpoints for structures with mainly beta sheets, viewpoint preference varies considerably for complex arrangements of alpha helices. Finally, experts tend to choose viewpoints of both low and high viewpoint entropy to emphasize different aspects of the respective structure. 相似文献
827.
A comparative evaluation by such parameters as alleviation of pain syndrome, improvement of peripheral resistance and vegetotrophic processes, a decline in pareses and sensory disorders has been performed in 3 groups of patients: group 1 underwent benzohexonium electrophoresis, group 2 benzohexonium electrophoresis in the magnetic field produced by the unit "Polyus-I" followed by low-frequency electrotherapy with bipolar impulse current, group 3 benzohexonium electrophoresis in the magnetic field from the unit "ADMT-Magnipuls" followed by low-frequency electrotherapy with bipolar impulse current. The best clinical and physiological results were reported in group 3 patients. 相似文献
828.
Thermal analysis of peritectic alloys 总被引:1,自引:0,他引:1
Predictions that increasing cooling rate will result in increasing elevation of the apparent peritectic arrest temperature have been confirmed for Cd-Ag and Zn-Cu alloys in line with observations of Al-Ti alloys. The shape of the peritectic cooling curve is related to the competition between the peritectic transformation and direct crystallization from the melt in the formation of the secondary phase. The effect on solidification of the relative depressions of the and liquidus during cooling is considered. 相似文献
829.
830.
Andrea Marini Conor Hogan Myrta Grüning Daniele Varsano 《Computer Physics Communications》2009,180(8):1392-1403
yambo is an ab initio code for calculating quasiparticle energies and optical properties of electronic systems within the framework of many-body perturbation theory and time-dependent density functional theory. Quasiparticle energies are calculated within the GW approximation for the self-energy. Optical properties are evaluated either by solving the Bethe-Salpeter equation or by using the adiabatic local density approximation. yambo is a plane-wave code that, although particularly suited for calculations of periodic bulk systems, has been applied to a large variety of physical systems. yambo relies on efficient numerical techniques devised to treat systems with reduced dimensionality, or with a large number of degrees of freedom. The code has a user-friendly command-line based interface, flexible I/O procedures and is interfaced to several publicly available density functional ground-state codes.
Program summary
Program title:yamboCatalogue identifier: AEDH_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEDH_v1_0.htmlProgram obtainable from: CPC Program Library, Queen's University, Belfast, N. IrelandLicensing provisions: GNU General Public Licence v2.0No. of lines in distributed program, including test data, etc.: 149 265No. of bytes in distributed program, including test data, etc.: 2 848 169Distribution format: tar.gzProgramming language: Fortran 95, CComputer: any computer architecture, running any flavor of UNIXOperating system: GNU/Linux, AIX, Irix, OS/XHas the code been vectorised or parallelized?: YesRAM: 10-1000 MbytesClassification: 7.3, 4.4, 7.2External routines:- •
- BLAS (http://www.netlib.org/blas/)
- •
- LAPACK (http://www.netlib.org/lapack/)
- •
- MPI (http://www-unix.mcs.anl.gov/mpi/) is optional.
- •
- BLACS (http://www.netlib.org/scalapack/) is optional.
- •
- SCALAPACK (http://www.netlib.org/scalapack/) is optional.
- •
- FFTW (http://www.fftw.org/) is optional.
- •
- netCDF (http://www.unidata.ucar.edu/software/netcdf/) is optional.