Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS) * at Purdue University in 1 957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dissemination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all con cerned if the printing and distribution of the volumes were handled by an interna tional publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Cor poration of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 36 (thesis year 1991) a total of 11,024 thesis titles from 23 Canadian and 161 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this important annual reference work. While Volume 36 reports theses submitted in 1991, on occasion, certain univer sities do report theses submitted in previous years but not reported at the time.

Weather affects cattle production through the health, well-being, and performance of pastureland, rangeland, and cattle, and any increased variation should be a concern for cattle producers. A multi-period linear programming (MLP) model is used to identify livestock management activities that maximize the present value of net returns over a multi-year planning horizon, given variation in prices and weather conditions in Southeast Wyoming. Historical data from the USDA-ARS High Plains Grasslands Research Station is used to estimate the impacts of growing season precipitation variation on livestock performance indirectly through impacts on forage production and directly through impacts on calf gain. The MLP model incorporates these relationships over a suite of precipitation forecasts and potential financial management decisions in order to determine the impact of precipitation changes on the viability of cattle producers in the region. Results indicate that precipitation variation negatively impacts profitability of cattle enterprises with dry years having larger negative impacts than positive impacts associated with wet years. Models based on static weather tend to over-estimate profitability when compared to models that include historical precipitation variation. In addition, sources of supplemental funds impact both the risk associated with profit variability and the responsiveness of profitability to precipitation and cattle price cycles.