Probe goal functions

The goal functions are used in Probe. Follow the procedure of Section 4.D.3. When you obtain the Probe plot of the transfer curve V(Vo) versus V Vin below, continue with this section ... 

Next, we would like to find the values of ViL, ViH, V0l, V0h. NMh, and NMl. Before we continue, we will instruct Probe to display the points used in the evaluation of goal functions. Select Tools and then Options from the Probe menu bar ... 

Probe draws a plot of the traces used in the goal function (dy/VO)) and V(VO) in this example), labels the locations of the points used in the goal function (Pi and P2 in this example), and then displays the value of the goal function. The value of Vqh is 4.5868 volts. Select Window and then New to obtain a new Probe window ... 

Goal functions can be used to obtain numerical data from Probe graphs. The result of evaluating a goal function is a single numerical value. 

We will now evaluate the goal function. In Probe, select Trace and then Eval Goal Function ... 

Probe plots the trace V(VO), locates the 3dB point, and then marks the point on the plot. Note that the plot of V(VO) is not in decibels. The plot is generated only if you have Probe set to display the plot used for the evaluation. If this option is not set, a small dialog box will appear and tell you the result of the goal function. To check the setting, select Tools and then Options from the Probe menus ... 

It is with each of these reactions in mind that researchers probe the functionality of SCR catalysts with a goal of developing functional models that predict their behavior under a wide range of conditions. 

Quantitative analysis using FAB is not straightforward, as with all ionisation techniques that use a direct insertion probe. While the goal of the exercise is to determine the bulk concentration of the analyte in the FAB matrix, FAB is instead measuring the concentration of the analyte in the surface of the matrix. The analyte surface concentration is not only a function of bulk analyte concentration, but is also affected by such factors as temperature, pressure, ionic strength, pH, FAB matrix, and sample matrix. With FAB and FTB/LSIMS the sample signal often dies away when the matrix, rather than the sample, is consumed therefore, one cannot be sure that the ion signal obtained represents the entire sample. External standard FAB quantitation methods are of questionable accuracy, and even simple internal standard methods can be trusted only where the analyte is found in a well-controlled sample matrix or is separated from its sample matrix prior to FAB analysis. Therefore, labelled internal standards and isotope dilution methods have become the norm for FAB quantitation. 

NMR is a powerful and versatile tool for structural studies of biological RNAs and complexes they form with other nucleic acids, proteins, and small molecules. The goal of these studies is to determine the role that structure and dynamics play in biological function. NMR has the capacity to determine high-resolution structures, as well as to map RNAiligand interfaces at low resolution. Most structures of RNA and RNA-ligand complexes are under 20 KDa in size however, recent advances allow for determination of solution structures of complexes up to 40 kDa. NMR can also probe dynamic motions in RNA on micro- to millisecond time scales. A number of biologically relevant internal motions such as... 

The usual goal of the STS experiment is to probe the DOS distribution of a sample surface. Eq. (14.4) means that this measurement is meaningful only when the tip DOS as a function of energy over the range of measurement is known a priori. Otherwise, the sample DOS does not have a definitive relation to the tunneling spectrum. If the tip DOS is a constant, then Eq. (14.4) implies... 

The generation, stability, and function of tyrosyl radicals in ribonucleotide reductase, PGH synthase, and galactose oxidase continue to be active areas of research. The difficulties encountered in preparing and handling these proteins, as well as in probing the physical properties and reactivity of their metal-phenoxyl radical active sites, make the preparation and investigation of stable phenoxyl radical metal model complexes an attractive goal. 

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