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101.
The paper describes the clinical and morphological features of a congenital neurological disease affecting two in-bred litter-mate kittens. The principal neurological features were ataxia and dysmetria. In one of the kittens light microscopy revealed widespread vacuolation of white and grey matter of the brain and spinal cord. Electron microscopy revealved intra-myelinic vacuolation and some expansion of the extracellular space. Neuronal, axonal and glial changes were not seen, nor was there evidence of myelin breakdown. The entity is compared with congenital brain oedema of calves and spongy degeneration of the CNS in man. 相似文献
102.
David L. Trimm Anders Holmen Odd Lindvag 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1981,31(1):311-316
Studies have been carried out on the effect of pre-sulphiding a nickel-chromium-iron alloy on coke formation under steam cracking conditions. Pre-sulphiding has no great effect on the gaseous product spectrum as long as some sulphur is present, but the coking rate is dependent on the amount of sulphur pre-deposited. Small amounts of sulphur reduce the coke formation, but the coking rate increases with increasing amounts of pre-deposited sulphur. As the sulphur content increases still further, coke formation passes through a maximum. A tentative explanation of these observations is advanced in terms of the effect of metal sulphides on the established mechanism of coke formation. Initial sulphiding is suggested to increase grain boundary penetration by coke and to result in the accumulation of iron sulphide on the surface. Eventually this may act to seal off grain boundaries, thereby inhibiting further coke formation. 相似文献
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Dynamic behavior of an analog-to-digital converter (ADC) based on diffractive optical element(s) (DOE)(s) was studied and found to be in agreement with predictions. The analog signal was translated to an angular deflection of a laser beam by means of an acousto-optic (AO) cell. The number of bits in this experimental demonstration was three, using an eight-element DOE array. The maximum sample rate was found to be 2.5 MS/s, the limiting factor being the transit time for the acoustic wave across the width of the laser beam in the AO cell. The study is intended as a first dynamic demonstration of a proposed ADC scheme previously demonstrated in a quasi-static version. The full potential of the ADC scheme will require the use of a fast tunable diode laser to replace the AO deflection scheme used here. 相似文献
106.
The proton magnetic resonance spectroscopic imaging techniques that use read gradient during acquisition produce proton spectra
with high spatial and moderately high spectroscopic resolution in a reasonable time forin vivo applications. These techniques suffer mainly from the spatial and pectral distortions caused by the convolution of spectral/spatial
information (chemical-shift artifacts) and from the spectral shifts caused by static magnetic field inhomogeneities. The investigators
analyze the chemical-shift artifacts in the presence of nonnegligible static magnetic field inhomogeneities and propose a
postdetection processing scheme to correct for such effects. Spectral artifacts caused by chemical shifts, spectral line overlapping,
streak broadening, and magnetic field inhomogeneities are discussed. The postdetection data processing scheme is demonstrated
on measurements of a phantom as well as a human leg.
Supported by the Swedish Medical Research Council, project B-96-17x-006676-14A, and by Uppsala University are gratefully acknowledged.
One of us (J.W.) is indebted to the Institute of Measurement Science, Slovak Academy of Sciences, for continuous support,
VEGA Grant No. 95/5305/585,468 & 2/1207/96 相似文献
107.
This study investigated how the type of event witnessed and a repeated test schedule for confidence influenced the realism in confidence judgments. The experimental design contrasted 2 film versions (a violent and a nonviolent scenario) and 3 tests of confidence (immediate, repeated, and delayed). On average, for all single items, participants were highly overconfident in their judgments. However, the same participants severely underestimated their own performance when they, at the end of the test session, were asked to provide an estimate of how many questions they thought they had answered correctly. Whereas the effects on realism in confidence for the 2 different film versions were small, the realism in witnesses' confidence judgments increased when participants repeated their confidence ratings. The theoretical and forensical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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The degree of interaction between selected organic biocides (tebuconazole, propiconazole, and IPBC) and wood under supercritical conditions was investigated using a supercritical fluid chromatograph. The biocides were carried through a sawdust column by CO2 at various conditions. Retention times differed markedly both between the examined biocides and between physical conditions. Tebuconazole showed a higher affinity for wood than the other biocides. For all biocides, wood affinity was highest and, thus, fluid affinity lowest, at lowest pressures. 相似文献
110.
Large-eddy simulations (LES) and Reynolds-averaged Navier-Stokes (RANS) simulations of the interaction of the second pulse with the first pulse in a double-injection event are presented in this study. The opposing effects of the turbulence generated by the first pulse to accelerate mixing of the second pulse, and the residual bulk velocity from the first pulse to accelerate penetration of the second pulse are analyzed. The LES results show greater influence of the turbulence whereas the RANS results show greater influence of the bulk velocity. 相似文献