Conformational studies of various hemoglobins by natural-abundance 13C NMR spectroscopy

Studies of variously liganded hemoglobins (both from human and rabbit) by natural-abundance 13C NMR spectroscopy have revealed apparent conformational differences that have been interpreted on the basis of two quaternary structures for the α2ß2 tetramer, and variable tertiary structures for the individual α and ß subunits. In solution, rabbit hemoglobins appear to have somewhat more flexibility than human hemoglobins

Pricing Weather Derivatives

This paper presents a general method for pricing weather derivatives. Specification tests find that a temperature series for Fresno, California follows a mean-reverting Brownian motion process with discrete jumps and ARCH errors. Based on this process, we define an equilibrium pricing model for cooling degree day weather options. Comparing option prices estimated with three methods: a traditional burn-rate approach, a Black-Scholes-Merton approximation, and an equilibrium Monte Carlo simulation reveals significant differences. Equilibrium prices are preferred on theoretical grounds, so are used to demonstrate the usefulness of weather derivatives as risk management tools for California specialty crop growers.derivative, jump-diffusion process, mean-reversion, volatility, weather, Demand and Price Analysis,

Transient heat and mass transfer analysis of supercritical cryogenic storage systems with spherical static heaters Final report

Transient heat and mass transfer analysis of supercritical cryogenic storage systems with spherical static heaters by computer progra

WEATHER DERIVATIVES: MANAGING RISK WITH MARKET-BASED INSTRUMENTS

Accurate pricing of weather derivatives is critically dependent upon correct specification of the underlying weather process. We test among six likely alternative processes using maximum likelihood methods and data from the Fresno, CA weather station. Using these data, we find that the best process is a mean-reverting geometric Brownian process with discrete jumps and ARCH errors. We describe a pricing model for weather derivatives based on such a process.Risk and Uncertainty,

Economic Performance in Alberta Dairy: An Application of the Mimic Model

Dairy production at the farm-level is undergoing a rapid transformation in preparation for more open competition in the future. However, the means by which dairy farms can best improve their economic performance is of some question. Using measures of allocative, technical, and overall efficiency as indicators of a latent "performance" variable, this study specifies and estimates a multiple-indicator, multiple-cause (MIMIC) model of Alberta dairy production. Variables thought to "cause" performance include herd size, milk yield, breeding and veterinary expense, capital-to-labour ratio, concentrate-to-forage ratio, and operator experience. The results show that gains in performance may be made through increased capital intensity, greater spending on breeding and herd health, and, albeit marginally, through increased milk yields. Despite current trends toward larger dairy herds, this may not be a fruitful avenue for future improvements in dairy efficiency.Livestock Production/Industries,

Cost and Efficiency in Alberta Dairy Production

This study investigates the relationships between farm size, milk yield, cost of production, and technical efficiency in the Alberta dairy industry. Estimates of a stochastic production frontier are obtained with two alternative methods; an iterative "average frontier: (AF) procedure and a maximum-likelihood composed error (CE) term method. An index of technical efficiency is calculated for every herd in the sample, with the AF method resulting in an average efficiency ratio of 85 percent, and the CE method producing an average efficiency ratio of 83 percent. Regressions of production cost on milk output, herd size, and efficiency are used to test for the effects of size economies, yield economies, and technical efficiency on production cost. These results suggest that herd expansion, on average, would lower the average cost of production throughout the province. Romain and Lambert use a similar method in a study of Quebec and Ontario dairy farmers which shows a limited potential to exploit economies of herd size. While not a formal test of the similarity of the two industries, the results of this study indicate a significant difference between the optimal structure of dairy production in Alberta and Quebec. Such regional differences will have important implications for the possible reapportionment of the national milk market, whether by regulatory or free-market mechanisms.Livestock Production/Industries,