Physics of cellular synthesis, growth and division annual status report, 1 apr. 1964 - 31 mar. 1965

Physics of cellular synthesis, growth, and division

Physics of cellular synthesis, growth and division Progress report, 1 Oct. 1965 - 31 Mar. 1966

Growth, division, structure, and function of bacterial cel

The physics of cellular synthesis, growth and division

Three areas of research in NASA'S University Program are described. Primitive terrestrial living cells were studied as a guide to the kind of cells to look for in extraterrestrial life. Experiments in zero gravity conditions are described with emphasis upon effects on small organisms. The effects of ionizing radiation on cells are studied so that it will be possible to predict dosages which can be tolerated by humans with no permanent damage

Relative Entropy in Biological Systems

In this paper we review various information-theoretic characterizations of the approach to equilibrium in biological systems. The replicator equation, evolutionary game theory, Markov processes and chemical reaction networks all describe the dynamics of a population or probability distribution. Under suitable assumptions, the distribution will approach an equilibrium with the passage of time. Relative entropy - that is, the Kullback--Leibler divergence, or various generalizations of this - provides a quantitative measure of how far from equilibrium the system is. We explain various theorems that give conditions under which relative entropy is nonincreasing. In biochemical applications these results can be seen as versions of the Second Law of Thermodynamics, stating that free energy can never increase with the passage of time. In ecological applications, they make precise the notion that a population gains information from its environment as it approaches equilibrium.Comment: 20 page

Now the wars are over: The past, present and future of Scottish battlefields

Battlefield archaeology has provided a new way of appreciating historic battlefields. This paper provides a summary of the long history of warfare and conflict in Scotland which has given rise to a large number of battlefield sites. Recent moves to highlight the archaeological importance of these sites, in the form of Historic Scotland’s Battlefields Inventory are discussed, along with some of the problems associated with the preservation and management of these important cultural sites

Pass-through estimates and the choice of an exchange rate index

We examine exchange rate pass-through into U.S. import prices in 29 manufacturing industries using eight exchange rate indexes. These indexes vary by the number currencies included; whether the weight on each currency is based on total trade with the United States or solely imports; and, whether the weights vary by industry. Our results indicate that pass-through is generally incomplete but varies across industries. Moreover, pass-through is sensitive to the exchange rate index. Using bootstrapped J tests we show that major currency indexes perform better than their broad currency counterparts. When using a major currency index, industry-specific exchange rate indexes are preferred to aggregate indexes.Foreign exchange rates

Constructing and using national and regional TWEXs: the case for chaining

The breakdown of the Bretton Woods system of fixed exchange rates spurred the development of trade-weighted exchange rates(TWEXs). These indexes measure changes in the average foreign exchange value of a currency over time. The construction of a TWEX index requires numerous decisions. Producers of TWEXs are revisiting many of their construction decisions because, with the advent of the single currency in Europe, all TWEXs will have to be modified. In addition, countries adopting the single currency may find it useful to develop their own TWEXs, similar to those that exist for regions within the United States. All commonly-used TWEXs are based on either a Laspeyres or Paasche price index. In the present paper we argue that producers of TWEXs should consider using the chain approach for the construction of their indexes because of an issue that affects TWEXs based on either Laspeyres or Paasche price indexes - the choice of base period. We illustrate this problem and show how it leads to different measures of exchange rate changes. A chain index, which links together the exchange rates and trade weights from year-to-year, eliminates the needs for a base period.Foreign exchange

Comparing manufacturing export growth across states: what accounts for the differences?

The expansion of United States manufacturing exports has spread unevenly across states. Cletus C. Coughlin and Patricia S. Pollard use shift-share analysis to account for the difference between a state’s manufacturing export growth and national manufacturing export growth between 1988 and 1998. Three effects are examined. The industry mix effect indicates that a state should have experienced export growth above the national average if its exports were relatively more concentrated in industries whose exports expanded faster than the national average. The destination effect indicates that a state should have experienced export growth above the national average if its exports were concentrated in foreign markets whose purchases from the United States expanded faster than the national increase in exports. The competitive effect is what remains after accounting for these two effects. Coughlin and Pollard find that the competitive effect, which in previous research was related to increases in human capital per worker, is the key determinant of a state’s relative export performance. Furthermore, the industry mix and destination effects, which are of similar importance, are generally dominated by the competitive effect in accounting for a state’s relative export performance.Manufactures ; Exports ; Regional economics