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Isolated mismatch

DWI negative scans can be obtained in one of three pathophysiological situations i) Hypoperfusion is present and can be detected by PI, but is not severe enough to cause diffusion changes. This situation represents a lesion that consists of an isolated mismatch without... [Pg.127]

Another way to improve the analysis of complex matrices can be the combination of a multidimensional system with information-rich spectral detection (31). The analysis of eucalyptus and cascarilla bark essential oils has been carried out with an MDGC instrument, coupling a fast second chromatograph with a matrix isolation infrared spectrometer. Eluents from the first column were heart-cut and transferred to a cryogenically cooled trap. The trap is then heated to re-inject the components into an analytical column of different selectivity for separation and subsequent detection. The problem of the mismatch between the speed of fast separation and the... [Pg.229]

Status epilepticus occurs because the brain fails to stop an isolated seizure. The exact reason for this failure is unknown and probably involves many mechanisms. A seizure is likely to occur due to a mismatch of excitatory and inhibitory neurotransmitters in the brain. The primary excitatory neurotransmitter in the brain is glutamate. Glutamate stimulates postsynaptic N-methyl-D-aspartate (NMDA) receptors in the brain, causing an influx of calcium into the cells and depolarization of the neuron. Sustained depolarization may maintain SE and eventually cause neuronal injury and death.7 The primary... [Pg.462]

There was still some room for uncertainty on this retention-retention mechanism. The argument was, if the unobserved tt-allyl Mo complex (such as 77 or B in Scheme 2.18) was more highly reactive towards sodium malonate than experimentally observed tt-allyl Mo complexes (such as 71, 74, and 80), the reaction should proceed through inversion (since there is an equilibrium between the two tt-allyl Mo complexes via the o-allyl complex.) If so, when the isolated Mo-complex 71 was subjected to the reaction, 71 must be equilibrated to the enantiomer of 71 via the o-allyl complex prior to reaction with a nucleophile. Therefore, reaction from the Mo complex 71 should proceed with less stereoselectivity than that from a mismatched branched carbonate. This hypothesis was examined, as shown in Scheme 2.26. [Pg.73]

As described above, it is probably adequately clear that the vibrational spectroscopy of water is complicated indeed One can simplify the situation considerably by considering dilute isotopic mixtures. Thus one common system is dilute HOD in D2O. The large frequency mismatch between OH and OD stretches now effectively decouples the OH stretch from all other vibrations in the problem, meaning that the OH stretch functions as an isolated chromophore. Of course the liquid is now primarily D2O instead of H2O, which has slightly different structural and dynamical properties, but that is a small price to pay for the substantial simplification this modification brings to the problem. [Pg.61]

Total RNA is isolated from the lymphocytes according to standard procedures and used as a template for radioactive labeled cDNA synthesis. The purified cDNA is used as probe for cDNA expression arrays. The advantages of this method as compared to other array systems are as follows (1) Radioactive-labeled probes are more sensitive than fluorescent-labeled probes and therefore need less sample RNA. (2) The primers used in the cDNA synthesis match the genes represented on the array. (3) The primer sequences are longer compared to other array systems, which increases the hybridization fidelity of RNA to the matching correct set of genes and therefore reduces mismatch reactions. [Pg.452]

An efficient kinetic resolution was also observed during the (—)-sparteine-mediated deprotonation of the piperidin-2-yhnethyl carbamate rac-112 (equation 25). By treatment of rac-112 with s-BuLi/(—)-sparteine (11), the pro-S proton in (/ )-112 is removed preferentially to form the lithium compound 113, which undergoes intramolecular cyclo-carbolithiation, and the indolizidinyl-benzyllithium intermediate 114 was trapped with several electrophiles. The mismatched combination in the deprotonation of (5 )-112, leading to cp/-113, does not significantly contribute to product formation. Under optimized conditions [0.75 equivalents of s-BuLi, 0.8 equivalents of (—)-sparteine, 22 h at —78°C in diethyl ether] the indolizidine 115 was isolated with 34% yield (based on rac-112), d.r. = 98 2, e.r. = 97 3 optically active (5 )-112 was recovered (46%, 63% ee). [Pg.1079]

The cultivated potato and many of its relatives are amenable to eell and tissue culture procedures, ineluding protoplast isolation and fusion. Somatic cell fusions have frequently been used to eombine the genomes of Solarium speeies that are sexually ineompatible because of pollen-stylar interactions or mismatched EBN numbers. Somatic fusion circumvents sexual reproduetion and results in novel eombinations of not only nuclear genomes, but also cytoplasmic genomes (Trabelsi et al., 2005 Bidani et al., 2007 Lovene et al., 2007). However, recalcitrant genotypes... [Pg.39]

One problem which arises when a detector array is attached to the face of a multi-layer module is the inability of the detector material to absorb forces generated by a mismatch of coefficient of thermal expansion between the detector array material and the module. Furthermore, it is difficult to isolate a fault that may be attributable to either the detector elements, module wiring or processing elements. [Pg.310]


See other pages where Isolated mismatch is mentioned: [Pg.128]    [Pg.128]    [Pg.77]    [Pg.245]    [Pg.20]    [Pg.25]    [Pg.171]    [Pg.245]    [Pg.245]    [Pg.12]    [Pg.69]    [Pg.821]    [Pg.391]    [Pg.228]    [Pg.160]    [Pg.74]    [Pg.53]    [Pg.108]    [Pg.72]    [Pg.468]    [Pg.660]    [Pg.1500]    [Pg.572]    [Pg.544]    [Pg.150]    [Pg.245]    [Pg.246]    [Pg.207]    [Pg.139]    [Pg.57]    [Pg.672]    [Pg.20]    [Pg.623]    [Pg.227]    [Pg.452]    [Pg.500]    [Pg.218]    [Pg.135]    [Pg.326]    [Pg.113]   
See also in sourсe #XX -- [ Pg.127 , Pg.128 ]




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