Parallel measurements

Before we leave the enhancement of the + R effect of S02Me by octet expansion, it is appropriate to mention its stereochemical aspect. This was examined by Kloosterziel and Backer in the later of their two papers to which reference has already been made78. They measured the pKa value of 4-methylsulfonyl-3,5-xylenol 25 and compared its acidity with that of 4-methylsulfonylphenol. Parallel measurements were made with 4-CN and 4-N02... 

Measurements of polymerization rate and parallel measurements on the resultant polymer microstructure in the butadiene/DIPIP system cannot be reconciled with the supposition that only one of the above diamine solvated complexes (eg. Pi S) is active in polymerization 162). This is probably true of other diene polymerizations and other diamines. The observations suggest a more complex system than described above for styrene polymerization in presence of TMEDA, This result is clearly connected with the increased association number of uncomplexed diene living ends which permits a greater variety of complexes to be formed. 

The aim of the study was to check this possibility. A quartz nanobalance was chosen as a sensitive tool (Sauerbrey 1964). The device allows monitoring of the mass attached to the surface of quartz oscillators (Facci et al. 1993). The method is simple, cheap, and sensitive (as it should be for practical applications) and allows one to make parallel measurements in different media, also permitting a differential scheme of measurements. 

The solid or dashed lines correspond to modified Michaelis-Menten kinetics assuming activation with one and inhibition with two molecules bound according to Eq. (15). Solid symbols represent average value of n = 3-5 parallel measurements made with one single cell preparation. (Adapted from Ref. [58].)... 

The current trends toward miniaturization and the need of massively parallel measurements led to the development of biochips. In this area, biocatalyzed and electrogenerated chemiluminescence reactions appear attractive and represent an alternative to fluorescence detection which is still widespread used despite the numerous problems of quantitative measurements and interference fluorescence emission. 

A typical example of such parallelized measurements is given in Figure 20. For a variety of inhibitors, the binding inhibition assay is given for a thrombin inhibition Figure 20 shows the binding curves obtained in parallel from 96 wells37. 

In a thorough study by Balia and coworkers, it was shown that in slightly acidic aqueous solution (25 °C, /jl = 1.0 KN03), the mechanism is very similar to that followed in aprotic media (36). Parallel measurement of the 02 consumption and quinone formation confirmed the following stoichiometry up to 35% conversion ... 

Pigments were separated on a normal (150 X 4 mm i.d., particle size 5 /tin) and on a microbore ODS column (150 X 2 mm i.d., particle size 4 jttm) using gradient elution. The steps of gradient elution are shown in Table 2.7. Carotenoids were detected at 440 nm. Columns were not thermostated and separations were performed at room temperature (20 2°C). The mean and the relative standard deviation of retention time and peak area were computed from three parallel measurements. The carotenoids capsanthin, zeaxanthin and j0-carotenein and the extracts were tentatively identified comparing their retention time with those of authentic standards. 

Fig. 3 Activation difference between the rapid visual information processing (RVIP) and control tasks in smokers after administration of placebo and nicotine patches. The graphs show the percent change in activation (from baseline) during performance of each task in smokers in the two drug conditions. After receiving nicotine, smokers demonstrated better task performance and more task-related activity in the parietal (A and B) and occipital (C and D) cortices compared to the parallel measures after they received placebo (Kumari et al. 2003)...

Figure 5 is the case of a mixture NBS 706 (98.5 %) and PS 411000 (1.5 %). The value of M of the mixture l s about 8 % higher than that of NBS 706, bu both values of M are nearly the same. Both normalized chromatograms have similar shapes as in the case of Figure 1. However, the sequential U test (Figure 6) revealed after the third pair of parallel measurements that the MWD of the mixture is different from that of NBS 706.

Figures 7 and 8 show the normalized chromatograms of NBS 706 and of the mixture of NBS 706 and ESBRITE. Molecular weight averages of each pair of runs can be regarded as Identical within the experimental errors. The chromatograms in Figure 7 were judged to be Identical by the sequential U test of four pairs of parallel measurements. Only two pairs of runs were necessary for the decision of disagreement in the case of Figure 8.

In conclusion, the sequential U test is useful for the judgement of identity between MWDs of a pair of polymer samples whose molecular weight averages are Identical within the experimental errors. Identity of MWDs of the two polymer samples was established with more than four pairs of parallel measurements, and the disagreement of MWDs with two to four pairs of parallel measurements. Though this statistical treatment is useful for the identification or differentiation of the MWDs of the pair of polymers, it can not detect small differences in shapes of the both chromatograms. 

The larger the amount of enzyme that can bind to the antibodies on the container s walls, the larger the amount of dye that is produced. Conversely, the larger the amount of the substance being assayed that is present in the sample, the smaller the amount of tracer that can be bound by the antibodies. Quantitative analysis can be carried out through parallel measurement using standards with a known concentration. 

Fig. 42. Magnetoelastic coefficient versus magnetic field applied parallel and perpendicular to the long axis of the cantilever (parallel measurement direction) of an as-sputtered TbFe/Fe multilayer deposited (a) without a dc field (H

A parallel setup is generally recommended, in which a different NMR tube is used for each measurement temperature (Table D3.1.1). However, when the amount of sample is limited, it may be necessary to use a serial rather than parallel experimental design. In a serial measurement, after measuring a sample at the first (lowest) temperature, it is transferred to the next warmest tempering block, held at the measurement temperature for the appropriate incubation time, and then remeasured. The process is repeated until the entire temperature range has been covered. Note that the solid fat content of a given sample is a function of thermal history, so serial and parallel measurements may give dissimilar results. 

At higher shear rates, Watanabe and Kotaka (1983) observed thixotropy, i.e. stress decay increasing as a function of shear rate, in PS-PB diblocks in dibutyl phthalate (DBP), which is a selective solvent for PS.The fact that the flow crossed over from plastic to viscous non-Newtonian on increasing the shear rate indicated the breakdown of the micellar lattice structure, rather than of the individual micelles. This was confirmed by parallel measurements on a cross-linked PB-PS system, where stress decay and recovery were also observed. Thus the... 

Figure 7.3 represents the stripping curves and the corresponding calibration plot (inset) for lead obtained for a iacc of 60 s and a 7strip of 1 pA. Each point in the calibration curve corresponds to the mean of three parallel measurements performed consecutively in the same cell without polishing the electrode. The error bars are the standard deviations of these measurements. Possible changes of graphite-epoxy electrode surface in contact with solution should have the effect of repeatability of the response. A DL of approximately 200 ppb of lead was determined... 

At this point, we had assembled a preliminary model of the human thrombin receptor that contained all three extracellular loops linked to the seven TM domains, as well as the N-terminus out to residue 75. Docking studies with agonist peptide SFLLRN, and additional mutagenesis experiments, were carried out in parallel. Measurement of the effects of site-specific mutations in human PAR-1 identified several key amino acids of the receptor as being important for activation (Table 1),... 

Fig. 1. Correlation of fertility with extent of nuclear DNA complementarity among heterothallic yeasts showing low to intermediate DNA relatedness. Mating responses parallel measurable DNA reassociation. These and other data suggest that strains showing 70% or greater DNA relatedness will, in most cases, represent members of the same biological species.10 37 P., Pichia /., Issatchenkia F., Filobasidiella.

The specificity of HG volume changes to schizophrenia is supported by parallel measurements in patients with affective psychosis or mania, where decreased HG volume was not found (Hirayasu et al., 2000 Kasai et al., 2003b McCarley et al., 2002 Salisbury et al., 2007). It is undetermined whether the volume change in schizophrenia precedes the onset of psychosis. Although some studies found a decreased volume at early onset of schizophrenia (Hirayasu et al., 2000 McCarley et al., 2002 Salisbury et al., 2007 Sumich et al., 2005), there is evidence that the volume deficit worsens with disease progression and drug treatment (Crespo-Facorro et al., 2004 Kasai et al., 2003b Salisbury et al., 2007). 

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