IFN-gamma-mediated prevention of graft-versus-host disease: pharmacodynamic studies and influence on proliferative capacity of chimeric spleen cells

Recently we demonstrated that prolonged administration of IFN-gamma prevented the development of GVHD in a MHC-mismatched murine BMT model. Treatment with IFN-gamma allowed the development of mature donor-derived allo-tolerant immunocompetent cells in complete chimeric recipients. Here we present data on the pharmacodynamics of this cytokine-mediated protection against GVHD. Treatment with 50000 U IFN-gamma twice weekly for a period of 5 weeks, starting at the day of BMT, was shown to be the optimal treatment protocol, resulting in complete prevention of GVHD-related mortality. Treatment during 1 week with a three-fold higher weekly dose of IFN-gamma (50000 U six times) did not result in significantly improved survival. The start of IFN-gamma administration was a critical factor since a delay of 3 days from the time of BMT resulted in substantial GVHD-induced mortality. Furthermore, it was shown that IFN-gamma treatment inhibited the spontaneous and Con-A-induced proliferation of T cells at 7-14 days after BMT, which is the critical period for the initiation of acute GVHD. However, long-term survivors after IFN-gamma treatment showed a recovery of immunity in contrast to long-term survivors of saline-injected animals, as tested by Con-A responsiveness. It seems that injection of high dose IFN-gamma suppresses the response of potentially alloreactive donor T cells during what normally is the initiation phase of the GVH reaction (GVHR), resulting in the abrogation of GVHD.     

Rate of heat release and ignitability indices for surface linings

Dimensional analysis is applied to one form of fire growth in a compartment to derive two indices for the classification of linings, an ignitability index and a rate of heat release index, that can be combined into a fire growth parameter, which here is made proportional to the time to flashover in the internationally standardized Room/Corner Test. The ignitability index is the inverse of the time to ignition. The rate of heat release index is obtained by integrating the rate of heat release in time, weighted in such a way that the values of rate of heat release immediately after ignition are of higher importance than those at later times. Both indices are determined from test results of the Cone Calorimeter.     

Discrete Sequence Prediction and Its Applications

Learning from experience to predict sequences of discrete symbols is a fundamental problem in machine learning with many applications. We present a simple and practical algorithm (TDAG) for discrete sequence prediction. Based on a text-compression method, the TDAG algorithm limits the growth of storage by retaining the most likely prediction contexts and discarding (forgetting) less likely ones. The storage/speed tradeoffs are parameterized so that the algorithm can be used in a variety of applications. Our experiments verify its performance on data compression tasks and show how it applies to two problems: dynamically optimizing Prolog programs for good average-case behavior and maintaining a cache for a database on mass storage.A preliminary version of this work appeared in Laird (1992a).     

An energy policy for Australia: Extracts from the summary report and recommendations of the Task Force on Energy of The Institution of Engineers,Australia

Over the next few years, Australia must modify its dependence on natural oil and place greater reliance on other fossil fuels and renewable energy sources. The management of this transition is a major task, and can only be successfully achieved through a co-ordinated programme of action by Commonwealth and State Governments, supported by widespread public understanding of the issues involved.The recommendations in this report have arisen from the deliberations of the Task Force on Energy, which commenced work in 1975. The Task Force and its associated twelve working parties included many of the leading energy experts in Australia, in engineering, science and economics. They are associated with State Governments and energy instrumentalities, Commonwealth agencies, private enterprise, consulting engineering, universities and research bodies, but have co-operated in the work of the Task Force in their personal capacities. Overall, at least one hundred key specialists were associated with the working party studies. There was wide-ranging national co-operation in these studies, and information on critical energy issues throughout Australia was freely exchanged.     

Responsibility and the elderly: Applications to psychotherapy.

Based on the analysis of P. Brickman et al (see record 1982-30315-001), 4 models of psychotherapy are proposed. It is argued that a key element in clinical interventions with the elderly is the extent to which the intervention affects the elderly clients' perceived responsibility for the cause of and solution to their presenting complaints. The dangers of a medical model psychotherapeutic orientation that strips clients' feelings of control are discussed. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Our environment?options on the way into the future

The electric power industry faces a dilemma?the need to supply ever-increasing quantities of electric energy and power vital to mankind and, at the same time, to control pollution of the environment to viable limits. This subject?the great environmental debate and the power industry?was discussed at a special session during the 1970 IEEE Summer Power Meeting and EHV Conference by a panel of experts from the electric power industry, state and federal regulatory bodies, and the nuclear community. The program centered around the following lecture by Philip Sporn, reprinted here in full, in which he takes as his theme sentence Loren Eiseley's statement, ``Increasingly there is but one way into the future: the technological way.'     

Reactivity of heat-treated coals in carbon dioxide at 900 °C

Reactivities of sixteen 40 × 100 (U.S.) mesh U.S. coals charred to 1000 °C were measured in carbon dioxide at 900 °C. Chars derived from coals with less than 80% carbon, on a dry-ash-free basis, were the most reactive. These chars also gave the widest spread in reactivity. Plots of inorganic element content in the chars versus reactivity showed that magnesium and calcium are important to char reactivity. Six coals were acid-washed with hydrochloric acid and four coals were further demineralized with hydrofluoric acid. Most acid-treated coals showed a decrease in reactivity; but two coals of high rank increased in reactivity. This increase in reactivity is attributed to the creation of additional porosity as a result of mineral matter removal and thus a reduction in resistance to carbon dioxide diffusion to reactive sites. Two demineralized and two original coals were divided into four size ranges and chars were produced from each size of each coal. Gasification rates increased monotonically with decreasing particle size reacted.