Minimization variables

Johnson, K., Swindell, A. Guidance in the setting of drug particle size specifications to minimize variability in absorption. Pharm. Res. 1996, 13, 1795-1798. 

It is important to carefully document core ADHD symptoms at baseline to provide a reference point from which to evaluate effectiveness of treatment. Improvement in individualized patient outcomes are desired, such as (1) family and social relationships, (2) disruptive behavior, (3) completing required tasks, (4) self-motivation, (5) appearance, and (6) self-esteem. It is very important to elicit evaluations of the patient s behavior from family, school, and social environments in order to assess the preceding. Using standardized rating scales (e.g., Conners Rating Scales-Revised, Brown Attention-Deficit Disorder Scale, and IOWA Conners Scale) in both children and adults with ADHD helps to minimize variability in evaluation.29 After initiation of therapy, evaluations should be done every 2 to 4 weeks to determine efficacy of treatment, height, weight, pulse, and blood pressure. Physical examination or liver function tests may be used to monitor for adverse effects. 

The ability of any experimental method to produce accurate and reproducible results and provide the sensitivity needed to discern differences between transport mechanisms depends on minimizing variability intrinsic to the method. However, formal error analysis is rarely undertaken, even for commonly used methods. Fawcett and Caton [45] performed an error analysis of the capillary method for determining diffusion coefficients more than 25 years after the method was introduced. The value of the analysis is that it reveals which factors contribute the greatest variability to the dependent variable of interest. In the case of transport studies, the dependent variable of primary interest is diffusant concentration, C(t), where... 

Luttinger-Tisza method is burdened by independent minimization variables, while analysis of the values of the Fourier components F k) makes it possible to immediately exclude no less than half of the variable set and to obtain a result much more quickly. Degeneracy of the ground state occurs either due to coincidence of minimal values of Vt (k) at two boundary points of the first Brillouin zone k = b]/2 and k = b2/2, or as a result of the equality Fj (k) = F2 (k) at the same point k = h/2. The natural consequence of the ground state degeneracy is the presence of a Goldstone mode in the spectrum of orientational vibrations.53... 

Drug/Food interactions To minimize variability, sirolimus should be taken consistently with or without food (see Administration and Dosage). 

Other main concerns raised by the experts also had to be managed in the laboratory to minimize variability ... 

The area under the dissolution curve (AUC=T6), was chosen as the major response to be optimized. Nevertheless, the results showed that it is necessary to study several properties to define the best formulation adequate powder flow, compression behaviour and particularly, a minimal variability of the dissolution parameters [3]. It was noted that good powder flow rate is not always related to an adequate compression behaviour [4]. 

There are some potential instrumental sources of error that could occur using this quantitation technique. It is critical to have minimal variability between each independent injection, as the quantitation is based on the comparison of the sample and standard areas. However, the current autosamplers are able to minimize this variability to less than 0.5% relative standard deviation (RSD). 

Taguchi classified robust designs according to the main objective when measuring the response in three basic types nominal-is-besf (minimal variability around a target value), larger-the-better (minimal variability for a maximum in the response) and smaller-the-bettef (minimal variability for a minimum in the response). 

As our objective is to maximise the s/n ratio, we select factor A at level 1 or 2 indistinctly, factor F at level 2 or 3, factor C at level 1 and factor D at level 2. With this selection we are sure to obtain minimal variability. However, we also need an average equal to 3.5. Table 2.18 summarises the Pareto ANOVA for the average and Figure 2.9 displays the contribution of each term when the average response of the experiments in the experimental matrix is considered. 

All the combinations shown in the table have minimal variability (high values of s/n ratio) but they lead to different average values. The closest average to the target is 3.54 for the combination A(2) B(3) C(l) D(2) F(3). The estimated s/n... 

Fluang X, Powell J, Mooney LA, Li C, Frenkel K (2001) Importance of complete DNA digestion in minimizing variability of 8-oxo-dG analyses. Free Rad Biol Med 31 1341-1351 Janata E (1982) Pulse radiolysis conductivity measurements in aqueous solutions with nanosecond time resolution. Radiat Phys Chem 19 17-21... 

Most modern minimization methods are designed to find local minima in the function by search techniques characteristically they assume very little knowledge of the detailed analytic properties of the function to be minimized, other than the fact that a minimum exists and therefore that, close enough to the minimum, the matrix of the second derivatives of the function with respect to the minimizing variables (the hessian matrix) is positive definite. 

Several studies have tested visual function after exposure to carbon monoxide. To minimize variability, McFarland et al. (1944) studied brightness discrimination in a small group of well-trained subjects. The subjects reported decreases in visual sensitivity at approximately 4.5% COHb. Another study reported no adverse effects on visual discrimination or depth perception in subjects with 8% or 12% COHb (Ramsey 1973). Luria and McKay (1979) reported no decrement in night vision with COHb of 9%. Davies et al. (1981) reported that at 7% COHb there was no effect on visual function. The studies described above used various visual paradigms, which could account for the differences in results. 

A basic concept in the Shewhart Chart methodology is the division of observations into rational subgroups to maximize variability between subgroups and to minimize variability within subgroups. As an example, if we are sampling four bottles from a filling line each... 

A comparative BA study is usually conducted in healthy humans, usually involving 12-30 volunteers depending upon the expected variability in the derived pharmacokinetic parameters. To minimize variability in derived parameters, the healthy volunteers should have certain characteristics such as age between 18 and 50 years, within normal weight range, and free from disease or any medication. The study protocol has to be approved by the institutional ethics committee. 

The minimization variables are the elements of the linear expansion coefficient matrix (T). 

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