Spectra data collected from a mixture defines an n-dimensional data space, and application of PCA techniques yields a subset of m-eigenvectors that effectively describe all variance in that data space. The relative purity andor concentration of oil-containing aliquots can be determined by cooling approximately equal volumes of two or more aliquots to a temperature near or below 0 degrees Celsius. In addition, methods are provided for supporting the survival and for activating natural interferon producing cells in vitro without exogenous IL-3 or GM-CSF. In use of the invention, should any design changes occur, only the parts as originally defined need to be modified, and the method is reapplied. The values for each of the three variables provide the equipment quantity for optimally allocating multi-service traffic concentrators. The hub is thus firmly attached to the patient, and no separate suturing is required.