Effect of resolution

Werlen, R.C. Effect of Resolution on the Shape of Mass Spectra of Proteins Some Theoretical Considerations. Rapid Commun. Mass Spectrom. 1994, 8, 976-980. 

Magnetic sector instruments (Chap. 4.3) were used first to demonstrate the beneficial effects of resolution on ESI spectra of biomolecules. [96,103,104] Fourier transform ion cyclotron resonance (FT-ICR, Chap. 4.6) instruments followed. [105-107] The more recently developed orthogonal acceleration of time-of-flight (oaTOF, Chap. 4.2 and 4.7) analyzers also present an effective means to resolve all or at least most peaks. [108-110]... 

Figure 9 The Effect of Resolution upon Mass Accuracy. The Overlaid Spectra Were Calculated for the Same Molecular Formula C101H145N34O44, at Resolutions of 200, 2000, and Infinity 313...

Poe, R. and Rutan, S., Effects of resolution, peak ratio, and sampling frequency in diode-array fluorescence detection in liquid chromatography, Anal. Chim. Acta, 283, 245-253, 1993. 

Damrau, E., Normand, M.D., and Peleg, M. (1997). Effect of resolution on the apparent fractal dimension of jagged force-displacement relationships and other irregular signatures. 

Figure 4.54. Resolution Alfects the Quality of an Image. The effect of resolution on the quality of a reconstructed image is shown by an optical analog of x-ray diffraction (A) a photograph of the Parthenon (B) an optical diffraction pattern of the Parthenon (C and D) images reconstructed from the pattern in part B. More data were used to obtain image D than image C, which accounts for the higher quality of image D. [(A) Courtesy of Dr. Thomas Steitz. (B) Courtesy of Dr. David DeRosier).]...

Figure 9.6. Effect of resolution on SNR for FT-Raman spectra of nylon, when total measurement time is kept constant.

In Figure 10.8 appears one of the best known of all demonstrations of the effect of resolution on the image obtained by Fourier transformation. The Taylor and Lipson (1964) illustration shows how the transform of a general object, a duck, becomes increasingly less distinct and featureless as the diffraction information included in the Fourier transform decreases. In Figure 10.9 is another example of Fourier termination effects, but there applied, again using optical diffraction, to a more relevant case, a two-dimensional crystal. 

Figure 26 The effect of resolution on FTs. (a) A picture of a duck and its FT. (b) A back transform of the duck using only the low-resolution terms of the FT. Only the general shape of the duck is discernible the details are lost. Reproduced from the web-based book Book of Fourier, University of York, UK, with permission from Kewin Cowtan reimplemented by I. Karonen.

Figure 11 Effect of resolution settings on peak intensity, all other tactors being equal. Compound analyzed on Micromass Quattro II, 3- J.L injection with 70/30 ACN/0.1% acetic acid, flow rate = 0.25 mL/min, MetaChem Phenyl 3, 5 lm, 2.0 X 50 mm.

Figure 3.47 Resolution affects the quality of an image. The effect of resolution on the quality of a reconstructed image is shown by an optical analog of x-ray diffraction ...

N.D. Martinez (1991). Artifacts or attributes Effects of resolution on the Little Rock Lake food web. Ecol. Monogr., 61, 367-392. 

It is interesting to observe the effect of resolution on the energy distribution measurement. This is illustrated in Fig. 11, which shows in... 

Figure 4.1 shows the effect of resolution on the electron density for histidine residues in three kinase protein structures of varying resolution. In the highly resolved structure, the density reveals the clear shape of a histidine one can resolve atomic centers in the density. In the less well-resolved structures, the interpretation is more subjective. Even in the high-resolution structure, a flip around the exocyclic bond would still yield a model that fitted to the density reasonably well. 

Figure 5. The effects of resolution choice on molecular lattice construction using DOl as an example. [A] A plot of the total number of lattice points as a function of resolution, and (B] a plot of the H distribution as a function of resolution, indicating that H-distribution values begin to approach theoretical levels at resolutions less than or equal to 2.8 angstroms. (Reproduced from Ref. 15. Copyright 1988 American Chemical Society.)...

Figure 6. The effect of resolution choice on predictivity. Each point represents an error in the predicted pKi of one of five substituted benzenes (taken from Table II) using a HASL made from the other four compounds.

Figure 9. The effects of resolution choice on HASL predictivity using comparisons between learning set and test set DHFR inhibitor data. Plots compare predictivities for both sets at 2.. and 3.2-angstrom resolutions. Correlation coefficients (r) are shown for each plot. (Continued on next page)...

FIG U RE 3.6 Effect of resolution on accurate mass measurement of mixtnres. 

Figure 33. Effect of resolution on peak shapes A) The protonated molecular cluster of human insulin (CisrHjgjNftjOyvSj,) recorded with FABMS B) Calculated at a resolution of 6000 (10% valley definition) with the monoisotopic mass at m/ = 5804.6455 C) The unresolved cluster with an average mass at rn/j = 5808.61 (Reproduced from [226], with permission)...

FIGURE 5.7 MIR spectrum of talc (a) effect of resolution on band shape, (b) effect of resolution on signal-to-noise. 

Figure 2.15. Effect of resolution level for basic reconstruction of a MWCNT (cross section).

Fig. 3.31. Arg vasopressin - Theoretical effect of resolution on the shape of the M+2 peak at m/z 1086.4. Theoretical mass spectra of the [vasopressin+H] ion and the five indicated resolution values (FWHM) have been superimposed and the bar spectrum corresponds to infinite resolution. Adapted from Ref [64] with permission. John Wiley and Sons Ltd., 1994.

Many factors affect the photometric accuracy of Fourier transform spectrometers. They include the effect of resolution and apodization on the spectrum, the reproducibility of the single-beam spectra, the accuracy of the zero level, and the linearity of the transmittance (T) scale. Several spectrometer manufacturers have observed that the 100% line on their instmments may be reproduced to better than 0.1% and, as a result, have claimed that their instruments are accurate to 0.1 %T. This is not necessarily the case, however, as we show below. 

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