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A self-consistent approach to defining nonequilibrium radiation temperature is discussed using the distribution of the energy over microstates. We begin rigorously with ensembles of Hilbert spaces and end with practical examples based mainly on the far from equilibrium radiation of lasers. We show that very high, but not infinite, laser radiation temperatures depend on intensity and frequency. Heuristic definitions of temperature derived from a misapplication of equilibrium arguments are shown to be incorrect. More general conditions for the validity of nonequilibrium temperatures also are established.

The conformational dynamics of Met-enkephalin are studied using a variety of united and explicit atom force fields to compare and contrast the dynamical behavior predicted by these two types of force fields in biological systems. A comparison of these dynamical properties indicates that the explicit atom and united atom force fields produce significantly different peptide dynamical properties.

Multidimensional potential energy surfaces for systems larger than about 15 atoms are so complex that interpreting their topographies and the consequent dynamics requires statistical analyses of their minima and saddles. Sequences of minimum-saddle-minimum points provide a characterization of such surfaces. Two examples, [Ar.sub.19], and [(KCl).sub.32], illustrate how topographies govern tendencies to form glasses or 'focused' structures, for example, crystals or folded proteins. Master equations relate topographies to dynamics. The balance between glass-forming and structure-seeking characters of a potential energy surface seems governed by sawtooth versus staircase topography and the associated collectivity of the growth process after nucleation., Computational methods, particularly molecular dynamics (1), quenching (2-4), conjugate gradient minimization (5), and eigenvector-following (6-11) are now efficient enough to locate all the minima and all the important saddles on [...]

Study is presented to show that three related clusters of thirteen particles bound by pairwise Morse potentials with different ranges are the vehicles for relating the dynamics and kinetics of these clusters to the topographies of their energy landscapes. The analyses are based on the distribution of minima and saddles, on the asymmetrics of the barriers and the kinetics of passage among the energy bands that the distributions of minima display.

An empirical investigations force field to be used in molecular simulations is developed for two N-oxide species, N,N,N-trimethylamine-N-oxide (TMAO) and N-methylmorpholine-N-oxide (NMMO). The intra- and intermolecular force field is parametrized mainly on the basis of quantum-chemical calculations and is tested against available experimental spectroscopic, crystallographic, and liquid state data.

Emphasizes the importance of giving attention to the mission and the quality of the staffs in national laboratories in the U. S. Dilemmas concerning national laboratories; Laboratories serving the U. S. Departments of Commerce and Energy and the National Aeronautics and Space Administration; Reason the U. S. should have national or federal laboratories; Missions of the laboratories.

The authors propose an alternative mechanism to science court, a procedure created by the Task Force of the Presidential Advisory Group on Anticipated Advances in Science and Technology to resolve disputes which arise from scientific facts essential in public policy decisions. The mechanism proposed is modeled on mediation. Its primary aim is not to resolve conflicts but to bring out the facts though better communication, whether differences between scientists remained or not. The only similarity between the mediation mechanism and "science court" is the selection of issues which will be tackled. The issues must not only be significant to policy but should also have technical components which are important and disputed at the same time.

The article discusses the energy crisis in United States. Increased demand for petroleum is attributed to the 50% ownership of Arab nations of petroleum supply industry, very slow construction of U.S.-based refineries, slow expansion of U. S. domestic natural gas reserves and the closure of coal mines in Britain. Three conditions including commodity-limited economy, energy-limited commodity and free-energy-limited economy are discussed to examine the dependence of industrialized nations on physical resources. Internal adjustments to higher energy prices, formation of blocs, development of energy resources, selection of best model in economic and political analysis, trade balance,and recycling are recommended to assure the supply of energy and the protection of environment.

The article discusses a report based on a research by R. Stephen and Margaret F. Fells of the Chemistry Department at the University of Chicago about the energy cost of automobiles in the United States. The research aims to provide the Institute of Environmental Quality of State of Illinois with aid in making decisions on the disposal of automobile hulks and of solid waste in general. It also analyzes one aspect of how to use materials and energy from a thermodynamic perspective. The study concludes that recycling junked automobiles and reusing the scrap in the manufacture of new ones would realize reductions in total power consumption.

A new dynamical propensity rule for transitions of a system crossing the barrier from one potential minimum to one another is derived from dynamical system theory. The numerical evidence of the rule's validity by applying it to the rearrangements of a cluster of six argon atoms is presented.

The article focuses on the United Nations Conference on the Human Environment held in Stockholm, Sweden. The Secretary-General of the Conference was Maurice F. Strong. The theme constantly present in the conference was the reconciliation of environmental quality with economic development. Many delegates believe that economic development should not be promoted at the expense of environmental quality.

The article talks about thermodynamic analysis and the means for achieving thermodynamic and environmental thrift. An analysis of the potential stored in the environment, which are in the form of energy and order, and their possible uses are offered. It discusses the system used in thermodynamic analysis, which consists of the materials that become the manufactured object. The thermodynamics associated with the manufacture of automobiles is offered as an example of this analysis. The means for achieving thrift include recycling, extending the life of the machine, and comparing the real and ideal costs.

The article presents a discussion on human survival, focusing on the option of making the perpetuation of the human race a primary positive goal in a thermodynamic view. The choice to make survival a primary option is not going to deprive man of its freedom of choice or the task of determining over what to do next. Man in his lifetime is presented with countless numbers of alternative choices, and these choices are connected to another, affecting one another that collectively it determines history or the future of man. In man's effort to survive, there are two societal considerations that matter, the stable and the unstable considerations. For a society to survive it has to make a distinction between the two and focus on the keeping the distinction while maneuvering towards stability.

The author reflects on the physical, biological and legal aspects of the pollution problem in the U.S. He assessed public attitude towards the polluted air in the country. He argued that the pollution patterns of various cities and neighborhoods differ considerably. This could be attributed to various air pollution sources including the power and heat generation, industrial processes, wastes incineration and transportation. He categorized the pollutants according to how well they are monitored.

Evolution of protein structure from random coil to native is first represented topologically by its time-dependent sequences of discretized Ramachandran basins occupied by successive backbone residues. Introducing energetic and entropic criteria at each instant of observation transforms the description from a structurally ambiguous topological representation to an unambiguous geometric picture of the folding process. The method is applied with success to folding of [Beta]-lactoglobulin, traditionally perplexing because of its reputed nonhierarchical folding pattern. This molecule passes through a stage, ca. 0.1 [micro]s duration, of transient, 'flickering' [Alpha]-helical structure, until a bit of tertiary structure forms that stabilizes the system long enough to allow it to pass to its native [Beta]-sheet.