Pseudo-high resolution

Special features high linear dynamic range simultaneous isotope analysis zoom lens, fixed collectors pseudo high resolution simultaneous isotope analysis simultaneous isotope analysis... 

Since polyatomic interferences are mainly located on the higher mass side of the peak of interest, pseudo high resolution mode can be applied in MC-ICP-MS.Thereby, the source slit is changed whereas the collector slit is not adjusted. In this way, the flat section of the spectral peak is maximized and finally there is no need to place a slit in front of every single collector of the MC device when measuring the analyte signal on one side (Figure 2.14(c)). 

The protein-DNA interactions have been analyzed in detail at high resolution in the complex between the 434 repressor fragment and the ORl containing 20mer DNA. A pseudo-twofold symmetry axis relates the halves of this complex. The symmetry is not exact since the nucleotide sequence of the DNA is slightly different in each half (see Table 8.2). However, the interactions between one protein subunit and one half of the DNA are very similar to those between the second subunit and the other half of the DNA since most of the bases that interact with the protein are identical in both halves. Details of the interaction are very similar to those in the complex with the palindromic synthetic 14mer of DNA shown in Figures 8.14 and 8.15. The base pairs at one end of the DNA, 1-14, 2-13, etc. are called base pairs 1, 2, etc. 

The NADP-IDH from Escherichia coli has been thoroughly studied. It is a dimeric protein of two identical 40-kDa subunits. High-resolution X-ray crystal structures have been determined for the enzyme with and without substrate [16,17], and for the pseudo-Michaelis complex of the enzyme with isocitrate and NADP [18], Structures of sequential intermediates formed during the catalytic action of IDH are also available [19], Additionally, the kinetic and catalytic mechanisms have been determined in detail [20], Amino acid residues which are involved in interactions with substrate, coenzyme, metal ions, and catalysis have been identified [10,21],... 

The first structural location of the taxane binding site [42] placed it in the interprotofilament space, thus supporting the biochemical results. However, this changed when the first high resolution 3D structure of the paclitaxel-tubulin complex was solved by electron-crystallography of a two-dimensional zinc-induced tubulin polymer [5]. The fitting of this structure into a three-dimensional reconstruction of microtubules from cryoelectron microscopy allowed a pseudo atomic resolution model of microtubules [43] in which the paclitaxel binding site was placed inside the lumen of the microtubules hidden from the outer solvent. 

Although structural studies of enveloped viruses have lagged behind those of nonenveloped viruses, progress in combining high-resolution cryo-EM results with independently derived atomic structures of virion components has provided pseudo-atomic resolution structures. In terms of whole virus particles, the greatest advances have been accomplished with spherical icosahedral enveloped viruses from the... 

The molecular formula of a molecule can also be defined by high resolution mass spectrometry (hrms). The observed mass for the molecular ion or pseudo molecular ion must normally be within 5ppm of the calculated mass for El (electron impact) measurements, or within lOppm for Cl (chemical ionization) measurements. It is important to note that high resolution mass spectrometry confirms that some molecules of a particular molecular formula are present in the sample, but does not give any indication of purity. Some other evidence of compound purity will therefore be required. 

With a chromatographic technique capable of routinely yielding preparative fractions, quantitative and C FT NMR was the major spectroscopic tool used for chemical characterization. The established utility of and C NMR for characterization of coal products is documented well. Unfortunately, high-resolution C FT NMR is not quantitative normally under operating conditions used typically. (It should be noted that quantitative FT NMR measurements also are not obtained routinely. The problem of variable spin lattice relaxation times (Ti s) is present also in FT NMR. In addition, the greater signal intensity of NMR in comparison with C FT NMR poses an additional potential problem of detector linearity in the FT NMR receiver.) For C FT NMR, variable spin lattice relaxation times (Ti s) and nuclear Over-hauser effects (a result of pseudo random noise decoupling) usually... 

Baldwin reported the detection of the [M-I]" ion in FAB mass spectra of synthetic cyclostellettamines obtained as iodide salts. Unequivocal proof of their structures was obtained by high resolution atomic pressure chemical ionisation (APCI)-MS experiments on the [M+H] pseudo-molecular ion of the corresponding uncharged bis-tethrahydropyridine obtained by reduction of cyclostellettamines [44]. 

Ritterazine B (27), [< ]D 43° (CH3OH), showed the (M + H)+ ion at m/z 899.5873 in the high-resolution FAB+ve, which agreed with the pseudo-molecular formula C54H79N2O9. The eastern hemisphere of ritterazine B (27) was found to contain a saturated ring D, a 5/5 spiroketal system, and an OH group at C-12. The western hemisphere of 27 was identical to that of ritterazine A (26). 

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