Thioether-catalysed tandem synthesis of furans and cyclic ethers or lactones

Acyclic conjugated ynenediones tethered to an alcohol or carboxylic acid are converted into furanyl-substituted cyclic ethers or lactones in a single step by treatment with the tetrahydrothiophene. Modest levels of diastereocontrol can be achieved in some cases where the presence of a substituent on the tether results in the creation of a second stereogenic centre upon formation of the cyclic ether or lactone

Structural Change and Competition in Seven U.S. Food Markets

Recent trends in mergers and acquisitions in the U.S. food sector food manufacturers, wholesalers, and retailers raise concerns about market power. In the presence of market power, farmers may receive lower than competitive farm prices, and consumers may pay higher than competitive retail prices. This study presents empirical tests of market power at the national level for seven food categories: beef, pork, poultry, eggs, dairy, fresh fruit, and fresh vegetables. At the national level, our tests provide evidence of competitive conduct in both the sale of final food products and the purchase of farm ingredients.retail food and farm prices, market power, structural change, cointegration, Agribusiness, Industrial Organization,

Will Fat Taxes Cause Americans to Become Fatter? Some Evidence from US Meats

Price and income elasticities of fat from meats are estimated by decomposing composite demand for meat into the produ ct of total calories, the fraction of calories eat as fat, and a residual measure of quality. This demand-characteristic system provides estimates of the impact of prices and income on the fraction of calories eaten as fat as well as their affect on the total consumption of fat. Empirical estimates of the comp ensated own-price elasticities of meats suggest that a fat tax designed to raise revenues to finance nutritional education efforts may increase the total consumption of fat.Agricultural and Food Policy, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety,

Consequences of BSE disease outbreaks in the Canadian beef industry

This study examines farm to wholesale prices spreads to measure the impact of the BSE disease outbreak on the Canadian beef industry. The study uses structure break tests developed by Gregory and Hansen (1996) and Hansen (1992) examine possible breaks within co integrating relationships. The study finds evidence that the industry began realignment as a result of the UK BSE disease outbreak, and the Canadian BSE disease outbreak was simply the largest realignment of the process beginning with the UK disease outbreak. However, the only statistically significant break was the BSE disease outbreak itself in May 2003. Stability was not restored until the border was reopened in 2005. Specific results indicated that the processing sector exploited the border closure in May 2003 to enhance its market power and that the system returned to a competitive one after the border re-opened in July 2005.Beef industry, price transmission, BSE, market power, parameter instability, cointegration with structural break, Agribusiness, Agricultural and Food Policy, Agricultural Finance, GA, IN,

Stability radius and internal versus external stability in Banach spaces: an evolution semigroup approach

In this paper the theory of evolution semigroups is developed and used to provide a framework to study the stability of general linear control systems. These include time-varying systems modeled with unbounded state-space operators acting on Banach spaces. This approach allows one to apply the classical theory of strongly continuous semigroups to time-varying systems. In particular, the complex stability radius may be expressed explicitly in terms of the generator of a (evolution) semigroup. Examples are given to show that classical formulas for the stability radius of an autonomous Hilbert-space system fail in more general settings. Upper and lower bounds on the stability radius are provided for these general systems. In addition, it is shown that the theory of evolution semigroups allows for a straightforward operator-theoretic analysis of internal stability as determined by classical frequency-domain and input-output operators, even for nonautonomous Banach-space systemsComment: Also at http://www.math.missouri.edu/~stephen/preprint

THE RELATIONSHIP BETWEEN PRICE STABILIZATION AND CYCLES IN THE CANADIAN WHEAT MARKET

In this study, moving average price stabilization schemes were analyzed under the assumption of rational expectations. It was shown that moving average price schemes may induce cyclical behavior into market prices where no cyclical pattern previously existed. Moving average price stabilization schemes are important to Canadian agricultural policy analysis because they are a characteristic of stabilization programs in Canada. Indeed, the Agricultural Stabilization Act, introduced in 1975, and the Gross Revenue Insurance Program, introduced in 1991, use moving average prices to calculate returns to producers.Demand and Price Analysis,

Time variation in the inflation passthrough of energy prices

From Bayesian estimates of a vector autoregression (VAR) which allows for both coefficient drift and stochastic volatility, we obtain the following three results. First, beginning in approximately 1975, the responsiveness of core inflation to changes in energy prices in the United States fell rapidly and remains muted. Second, this decline in the passthrough of energy inflation to core prices has been sustained through a recent period of markedly higher volatility of shocks to energy inflation. Finally, reduced energy inflation passthrough has persisted in the face of monetary policy which quickly became less responsive to energy inflation starting around 1985.

CONSISTENT AGGREGATION IN FOOD DEMAND SYSTEMS

Two aggregation schemes for food demand systems are tested for consistency with the Generalized Composite Commodity Theorem (GCCT). One scheme is based on the standard CES classification of food expenditures. The second scheme is based on the Food Guide Pyramid. Evidence is found that both schemes are consistent with the GCCT.Demand and Price Analysis,

BSE Disease Outbreaks, Structural Change and Market Power in the Canadian Beef Industry

This study examines farm to wholesale prices spreads to measure the impact of the Bovine Spongiform Encephalopathy (BSE) disease outbreak on the Canadian beef industry. The study uses structure break tests developed by Gregory and Hansen (1996) and Hansen (1992) examine possible breaks within cointegrating relationships. The study finds evidence that the industry began a realignment as a result of the UK BSE disease outbreak, and the Canadian BSE disease outbreak was simply the largest realignment of the process beginning with the UK disease outbreak. However, the only statistically significant break was the BSE disease outbreak itself in May 2003. Stability was not restored until the border was reopened in 2005. Specific results indicated that the processing sector exploited the border closure in May 2003 to enhance its market power and that the system returned to a competitive one after the border re-opened in July 2005.BSE, market power, Canada, beef industry, Agribusiness, Industrial Organization, International Relations/Trade,