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The article describes two linear programming solutions to the assembly-line balancing problem. The balancing problem arises from a number of operations that must be performed sequentially with partial ordering constraints. The linear constraints are in variables that can be evaluated in linear objective functions. The linear programs developed to solve the balancing problem involve large numbers of constraint equations, variables, special integer variables. This makes complex the computations to develop an algorithm needed to solve the problem.

Recombination occurs at high frequencies in all examined retroviruses. The previously determined homologous recombination rate in one retroviral replication cycle is 4% for markers 1.0 kb apart in spleen necrosis virus (SNV). This has often been used to suggest that approximately 30 to 40% of the replication-competent viruses with 7- to 10-kb genomes undergo recombination. These estimates were based on the untested assumption that a linear relationship exists between recombination rates and marker distances. To delineate this relationship, we constructed three sets of murine leukemia virus (MLV)-based vectors containing the neomycin phosphotransferase gene (neo) and the hygromycin phosphotransferase B gene (hygro). Each set contained one vector with a functional neo and an inactivated hygro and one vector with a functional hygro and an inactivated neo. The two inactivating mutations in the three sets of vectors were separated by 1.0, 1.9, and 7.1 kb. Recombination rates after one round of replication were 4.7, 7.4, and 8.2% with markers 1.0, 1.9, and 7.1 kb apart, respectively. Thus, the rate of homologous recombination with 1.0 kb of marker distance is similar in MLV and SNV. The recombination rate increases when the marker distance increases from 1.0 to 1.9 kb; however, the recombination rates with marker distances of 1.9 and 7.1 kb are not significantly different. These data refute the previous assumption that recombination is proportional to marker distance and define the maximum recombining population in retroviruses.

Health care is entering into the era of value management--delivering high quality products and services at a reasonable price. This concept of delivery will have a definite effect on an organization's management strategies and tactics, especially in the area of information systems. Much re-evaluation of an organization's requirements for its information systems wil happen. As a result, a value-managed organization will place a greater demand on its information systems.

This article represents the first in a series examining the information management needs, both now and in 1988, of hospital CFOs. Future articles will focus on the management concerns of CFOs in relation to information, their current and projected use of information management products for long-range, strategic planning, and criteria for systems design. All these articles are based on HFMA members' opinions as voiced in a recent national poll. In all, more than 600 CFOs and data processing professionals responded to a recent survey sponsored by HFMA, HBO & Company, and Amherst Associates.