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At present for analysis of the homogeneity of materials properties are becoming widely used various modifications of a scanning Kelvin probe. These methods allow mapping the spatial distribution of the electrostatic potential. Analysis of the electropotential profile is not sufficient to describe any specific physical parameters of the polymer nanocomposites. Therefore, we use an external energy impact, such as light. Purpose of paper is the modification of the Kelvin scanning probe and the conduct of experimental studies of the spatial distribution and response of the electrostatic potential of the actual polymer nanocomposites to the optical probing.Carried out the investigations on experimental Low density polyethylene composites. Carbon nanomaterials and nanoparticles of silicon dioxide or aluminum as fillers are used. As a result, maps of the spatial distribution of the electrostatic potential relative values and the surface photovoltage. Statistical analysis of the electrophysical and photoelectric properties homogeneity, depending on the component composition of the composites carried out. In addition, with reference to matrix polymers, the Kelvin scanning probe, in combination with the optical probing, made it possible to detect a piezoelectric effect. The latter, can used as a basis for the development of new methods for studying the mechanical properties of matrix polymers.

Background There are few comprehensive estimates of the cost of psoriasis in the United States. Objective We sought to quantify the incremental direct medical and indirect work loss costs associated with psoriasis. Methods A de-identified claims database from 31 self-insured employers during the period 1998 to 2005 was used. Patients with at least two psoriasis diagnosis claims (N = 12,280) were compared with 3 control subjects (matched on year of birth and sex) without psoriasis. Multivariate two-part regression analysis was used to isolate the incremental cost of psoriasis by controlling for comorbidities and other confounding factors. Results After multivariate adjustment, the incremental direct and indirect costs of psoriasis were approximately $900 and $600 ( P Limitations The database used in this study does not contain information on patient out-of-pocket costs or loss of productivity costs at work. Conclusion The incremental cost of psoriasis is approximately $1500 per patient per year, with work loss costs accounting for 40% of the cost burden.

Using kernel density estimation we find that over the 1990s business cycles in the United States and Great Britain the entire distribution of after-tax (disposable) income moved to the right while inequality declined. In contrast, Germany and Japan experienced less growth, a rise in inequality, and a decline in the middle mass of their distributions, that spread mostly to the right, much like in the United States over its 1980s business cycle. Inequality fell within the older populations of all four countries; inequality also fell within the younger populations of the United States and Great Britain, but it rose substantially in Germany and Japan.

Using data from the March Current Population Survey, summary inequality measures as well as kernel density estimations, we find gains from economic growth over the 1990s business cycle (1989-2000) were more equitably distributed than over the1980s business cycle (1979-1989). The entire distribution of household size-adjusted income moved upwards in the 1990s with profound improvements for African Americans, single mothers and those living in households receiving welfare. Most gains occurred over the growth period 1993-2000. Improvements in average income and income inequity over the latter period are reminiscent of gains seen in the first three decades after World War II.