Method for detecting pollutants

A method is described for detecting and measuring trace amounts of pollutants of the group consisting of ozone, nitrogen dioxide, and carbon monoxide in a gaseous environment. A sample organic solid material that will undergo a chemical reaction with the test pollutant is exposed to the test environment and thereafter, when heated in the temperature range of 100-200 C., undergoes chemiluminescence that is measured and recorded as a function of concentration of the test pollutant. The chemiluminescence of the solid organic material is specific to the pollutant being tested

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

Altered white matter connectivity associated with visual hallucinations following occipital stroke

Introduction: Visual hallucinations that arise following vision loss stem from aberrant functional activity in visual cortices and an imbalance of activity across associated cortical and subcortical networks subsequent to visual pathway damage. We sought to determine if structural changes in white matter connectivity play a role in cases of chronic visual hallucinations associated with visual cortical damage. Methods: We performed diffusion tensor imaging (DTI) and probabilistic fiber tractography to assess white matter connectivity in a patient suffering from continuous and disruptive phosphene (simple) visual hallucinations for more than 2 years following right occipital stroke. We compared these data to that of healthy age-matched controls. Results: Probabilistic tractography to reconstruct white matter tracts suggests regeneration of terminal fibers of the ipsilesional optic radiations in the patient. However, arrangement of the converse reconstruction of these tracts, which were seeded from the ipsilesional visual cortex to the intrahemispheric lateral geniculate body, remained disrupted. We further observed compromised structural characteristics, and changes in diffusion (measured using diffusion tensor indices) of white matter tracts in the patient connecting the visual cortex with frontal and temporal regions, and also in interhemispheric connectivity between visual cortices. Conclusions: Cortical remapping and the disruption of communication between visual cortices and remote regions are consistent with our previous functional magnetic resonance imaging (fMRI) data showing imbalanced functional activity of the same regions in this patient (Rafique et al, 2016, Neurology, 87, 1493–1500). Long-term adaptive and disruptive changes in white matter connectivity may account for the rare nature of cases presenting with chronic and continuous visual hallucinations.York University Librarie

Infrequent Shocks and Rating Revenue Insurance: A Contingent Claims Approach

Revenue insurance represents an important new risk management tool for agricultural producers. While there are many farm-level products, Group Risk Income Protection (GRIP) is an area-based alternative. Insurers set premium rates for GRIP on the assumption of a continuous revenue distribution, but discrete events may cause the actual value of insurance to differ by a significant amount. This study develops a contingent claims approach to determining the error inherent in ignoring these infrequent events in rating GRIP insurance. An empirical example from the California grape industry demonstrates the significance of this error and suggests an alternative method of determining revenue insurance premiums.Black-Scholes, contingent claim, grapes, insurance, jump-diffusion, option pricing, Risk and Uncertainty,

Post Merger Performance of Agricultural Cooperatives

Agricultural cooperatives are participating in mergers, acquisitions, strategic alliances, and joint ventures at a record pace. While post-post merger performance has been examined extensively for investor owned firms, this has not been the case for agricultural cooperatives since these firms do not have an explicit profit motive nor publicly traded stock. Results from a three-stage econometric model reveal that a major motivation for cooperatives to engage in these activities is to circumvent unique capital constraints, thus resulting in improved profitability. Furthermore, the decision to merge and financial performance are jointly endogenous, with profitability positively influenced and sales growth negatively influenced by the likelihood of merger.acquisitions, capital constraints, cooperatives, financial performance, joint ventures, mergers, probit modeling, strategic alliances, Agribusiness,