Simulated obscuration data

Less is known about the interaction of the nucleosomes between themselves or with free DNA. The nucleosome-nucleosome interaction has recently been parameterized by using the surface charge density of the known crystal structure [39] in a point-charge model [51]. While in that work only electrostatic interactions were considered and the quantitative influence of the histone tails on the interaction potential still remains obscure, simulations based on this potential allowed to predict an ionic-strength dependent structural transition of a 50-nucleosome chromatin fragment that occurred at a salt concentration compatible with known experimental data (Ref. [65], see below). 

Using the concentration and obscuration measurements allow all of the kinetic parameters of interest to be identified. The simulated data is shown in Figures 1-2. The parameter estimation results corresponding to these measurements are given in Table 1. These results indicate that these measurements may provide enough process information to allow identification, even in the presence of measurement noise. This hypothesis is investigated experimentally in the next section. 

Maize Insect resistant 5.575 million pounds potentially less insecticide active ingredients in 2001 (14.927 million acres) Calculation of pesticide use in a simulation of high insect pest infestation based on historical data, assuming 100% pest control by insect resistant Bt maize. Rationale for the simulation were the low actual infestation levels in recent years that would have obscured the potential change in insecticide use under insect pressure. 

The great potential of the X-ray data for obtaining motional information has recently led to a molecular dynamics test197 of the standard refinement techniques that assume isotropic and harmonic motion. Since simulations have shown that the atomic fluctuations are highly anisotropic and, in some cases, anharmonic (see Chapt. VI.A.1), it is important to determine the errors introduced in the refinement process by their neglect. A direct experimental estimate of the errors resulting from the assumption of isotropic, harmonic temperature factors is difficult because sufficient data are not yet available for protein crystals. Moreover, any data set includes other errors that would obscure the analysis, and the specific correlation of temperature factors and motion is complicated by the need to account for static disorder in the crystal. As an alternative to an experimental analysis of the errors in the refinement of proteins, a purely theoretical approach has been used.197 The basic idea is to generate X-ray data from a molecular dynamics simulation... 

Most software connects plotted points with line segments (or splines) by default. This is often not appropriate. For example, if the points represent experimental data, only the points should be shown. Also, the joining of points obtained from process simulation on such a graph can obscure the maximum, minimum, and the shifts from one topology to another. More about these details is given in Chapter 14. 

Figure 12 Static Zr SSNMR spectra of [lnd2ZrCl2l. WURST-QCPMG spectra were acquired at a field of 21.1 T (A, C), and QCPMG experiments were acquired at 9.4 T (E). These spectra were constructed from several subspectra using the VOCS method of frequency-stepped acquisition. A one-site simulation of the 21.1 T spectrum is indicated by the unbroken gray line in (A), while a two-site simulation of the 21.1 T data is depicted by the unbroken and dashed gray lines in (B) and the unbroken gray line in (Q. A one-site simulation of the 9.4 T data is shown in (D), with a two-site simulation included as the unbroken gray line in (E). Note the satellite transitions in (E) that obscure the Zr powder pattern at 9.4 T. Reprinted with permission from Ref. [46]. Copyright The American Chemical Society 2009.

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