Two programs have been written which permit analysis of multiple continuous-rate enzyme-cascade assays conducted with the use of an ELISA spectrophotometer and a synthetic chromogenic substrate. Because the product of the first reaction functions as the enzyme in the second reaction, production of chromophore continuously accelerates and it is the rate of acceleration which serves to measure the rate of the initial reaction in the system. The first program determines the rate of acceleration using linear regression to analyze the reaction curves as a function of the square of time. The second program, using a Simplex algorithm, determines the parameters which establish the assay standard curve by fitting the rate data to the Hill equation. Used together, these programs facilitate the analysis of many kinetic experiments conducted simultaneously.
A computer program package has been constructed for use in patient survival analyses for chronic diseases based on aggregated data. The central concept of the analyses--the relative survival rate--is the ratio of the observed survival rate of the patients to the survival rate expected in a group in the general population similar to the group of patients at the beginning of the follow-up (interval), with respect to age, sex and calendar time. This quantity is used to measure patient survival adjusted for the effect of mortality attributable to the competing risks of death without employing information on causes of death of individual patients. The package contains three alternative methods of estimating the relative survival rates, two different ways of estimating the expectation of life for the patients, and five methods of testing the relative survival patterns using information on the whole follow-up period. Conventional survival and competing risk analysis can also be performed with the package. It is hoped that the package will facilitate standardization of statistical methodology and terminology in long-term survival studies for chronic diseases.
The glomerular capillary wall of the kidney behaves as an electronegatively charged structure consisting of three layers, the lamina densa and the two laminae rarae, which are differently chrrged. Thus, a three layer model is proposed to analyse the transport of charged macromolecules across this wall.
A program has been written to determine T-score profile patterns, thus allowing the immediate assessment of morphological similarities and differences between taxa. For a given data set, the program will produce T-scores, T-score correlation coefficients and associated significance statistics, weighted means and standard deviations for all input variables, and a graphic display of the T-score profile pattern(s). This program should prove to be of great interest to physical anthropologists, zoologists and other researchers in the life sciences with an interest in taxonomy, systematics and phylogeny.
A microcomputer program has been developed to aid field and laboratory anthropologists and demographers estimate biological dynamics of human populations.
