DEMAND AND PRICE-MARKUP FUNCTIONS FOR CANNED CLING PEACHES AND FRUIT COCKTAIL

This study formulates and estimates a six-equation model for canned cling peaches and fruit cocktail in which processors are viewed as price setters, with qualities not sold at the set price carried over to the next year. The system consists of two price-markup equations, two quantity-dependent demand equations and two inventory change identities. The three-stage least squares estimation results tend to support the behavioral hypotheses.Demand and Price Analysis,

Report on a visit to Mozambique

An ODA/DANIDA collaborative project in Mozambique is seeking to use collector boats to land and utilise shrimp by-catch usually discarded at sea by industrial trawlers. This resource is estimated to be 40,000 tonnes per year. This report documents a preliminary survey of the Zambezia province fishery in early 1991, by an NRI fish technologist and economist. The study sought to assess the economic feasibility of the proposed by-catch operation in the changing circumstances of the country and also the extent and nature of post-harvest losses in the traditional fishery

Consumer Demand for Food Commodities in the United States with Projections for 1980

This study analyzes the demand for food commodities in the United States in the postwar period using both time-series and cross-section data. Income-consumption relationships are based on data from 1955 and 1965 USDA household food consumption surveys. The analysis co cross section data emphasized: (1) effects of grouping observations, (2) choice between expenditures are quantities as the dependent variable, (3) effects of household size on income-consumption relationships, (4) shifts in the regression coefficients (intercepts and income elasticities) between 1955 and 1965, and (5) regional variations in the income-consumption relationships. A demand interrelationship matrix was developed for 49 commodities or commodity groups at the retail level. Commodities were classified into 15 separable groups and all direct and cross elasticities for commodities within a group were estimated directly. The cross elasticities corresponding to commodities outside a given group were estimated through assumptions of cardinal separability. The synthesis of demand interrelationships was achieved by the use of restrictions on demand equations for an individual consumer as suggested by Frisch (1959) and quantified by Brandow (1961). Consideration also was given to the measurement of time trends on consumption. Marketing margins were analyzed and demand interrelationships were developed at the farm level. Projections of 1980 consumption per capita were developed for individual commodities and group aggregates. These projections are based on a specification of constant real prices, exogenous projections of real income per capita, and continuation of past time trends for certain commodities.Demand and Price Analysis, Institutional and Behavioral Economics,

The Domestic and Export Markets for California Almonds

Crop Production/Industries, Marketing,

A Genome-Wide Over-Expression Screen Identifies Genes Involved in Phagocytosis in the Human Protozoan Parasite, Entamoeba histolytica

Functional genomics and forward genetics seek to assign function to all known genes in a genome. Entamoeba histolytica is a protozoan parasite for which forward genetics approaches have not been extensively applied. It is the causative agent of amoebic dysentery and liver abscess, and infection is prevalent in developing countries that cannot prevent its fecal-oral spread. It is responsible for considerable global morbidity and mortality. Given that the E. histolytica genome has been sequenced, it should be possible to apply genomic approaches to discover gene function. We used a genome-wide over-expression screen to uncover genes regulating an important virulence function of E. histolytica, namely phagocytosis. We developed an episomal E. histolytica cDNA over-expression library, transfected the collection of plasmids into trophozoites, and applied a high-throughput screen to identify phagocytosis mutants in the population of over-expressing cells. The screen was based on the phagocytic uptake of human red blood cells loaded with the metabolic toxin, tubercidin. Expression plasmids were isolated from trophozoites that survived exposure to tubercidin-charged erythrocytes (phagocytosis mutants), and the cDNAs were sequenced. We isolated the gene encoding profilin, a well-characterized cytoskeleton-regulating protein with a known role in phagocytosis. This supports the validity of our approach. Furthermore, we assigned a phagocytic role to several genes not previously known to function in this manner. To our knowledge, this is the first genome-wide forward genetics screen to be applied to this pathogen. The study demonstrates the power of forward genetics in revealing genes regulating virulence in E. histolytica. In addition, the study validates an E. histolytica cDNA over-expression library as a valuable tool for functional genomics

First-principles theory of ferroelectric phase transitions for perovskites: The case of BaTiO3

We carry out a completely first-principles study of the ferroelectric phase transitions in BaTiO$_3$. Our approach takes advantage of two features of these transitions: the structural changes are small, and only low-energy distortions are important. Based on these observations, we make systematically improvable approximations which enable the parameterization of the complicated energy surface. The parameters are determined from first-principles total-energy calculations using ultra-soft pseudopotentials and a preconditioned conjugate-gradient scheme. The resulting effective Hamiltonian is then solved by Monte Carlo simulation. The calculated phase sequence, transition temperatures, latent heats, and spontaneous polarizations are all in good agreement with experiment. We find the transitions to be intermediate between order-disorder and displacive character. We find all three phase transitions to be of first order. The roles of different interactions are discussed.Comment: 33 pages latex file, 9 figure

Noncommutative resolutions of ADE fibered Calabi-Yau threefolds

In this paper we construct noncommutative resolutions of a certain class of Calabi-Yau threefolds studied by F. Cachazo, S. Katz and C. Vafa. The threefolds under consideration are fibered over a complex plane with the fibers being deformed Kleinian singularities. The construction is in terms of a noncommutative algebra introduced by V. Ginzburg, which we call the "N=1 ADE quiver algebra"

Sustained NF-κB Activation and Inhibition in β-Cells Have Minimal Effects on Function and Islet Transplant Outcomes

The activation of the transcription factor NF-κB leads to changes in expression of many genes in pancreatic β-cells. However, the role of NF-κB activation in islet transplantation has not been fully elucidated. The aim of the present study was to investigate whether the state of NF-κB activation would influence the outcome of islet transplantation. Transgenic mice expressing a dominant active IKKβ (constitutively active) or a non-degradable form of IκBα (constitutive inhibition) under control of the rat insulin promoter were generated. Islets from these mice were transplanted into streptozotocin diabetic mice in suboptimal numbers. Further, the effects of salicylate (an inhibitor of NF-κB) treatment of normal islets prior to transplantation, and the effects of salicylate administration to mice prior to and after islet implantation were evaluated. Transplantation outcomes were not affected using islets expressing a non-degradable form of IκBα when compared to wild type controls. However, the transplantation outcomes using islets isolated from mice expressing a constitutively active mutant of NF-κB were marginally worse, although no aberrations of islet function in vitro could be detected. Salicylate treatment of normal islets or mice had no effect on transplantation outcome. The current study draws attention to the complexities of NF-κB in pancreatic beta cells by suggesting that they can adapt with normal or near normal function to both chronic activation and inhibition of this important transcription factor

Student Satisfaction and Performance in an Online Teacher Certification Program

The article presents a study which demonstrates the effectiveness of an online post baccalaureate teacher certification program developed by a Wisconsin university. The case method approach employing multiple methods and multiple data sources were used to investigate the degree to which pre-service teachers were prepared to teach. It was concluded that the study supports online delivery as an effective means of teacher preparation, but it was limited in the number of students followed into their first year of teaching