Spin diffusion in doubly spin polarized atomic deuterium

Using an extension of the Boltzmann equation for the Wigner distribution appropriate for dilute spin 1 systems, spin diffusion equations are derived in the limit of large nuclear polarization in the non-degenerate régime. As an example of a system to which this work may be applied, the domain of validity of the Boltzmann equation for doubly spin-polarized deuterium, D, is studied. The effect of a finite field gradient is discussed. A calculated spin wave spectrum for a model one-dimensional system in the presence of a gradient is presented. Analogous effects in spin 1/2 systems are compared and contrasted.This article appears in expanded from in K. A. Earle, Ph.D. thesis, Cornell University (1992).     

Integrating the implementation of the European Union Water Framework Directive and Floods Directive in Ireland

Water Framework Directive (WFD) statutory authorities and stakeholders in Ireland are now challenged with the issue of how the proposed programmes of measures in the newly required River Basin Management Plans - designed to protect and restore good ecology by reverting as closely as possible back to natural conditions - are to be implemented in a way that concurrently complies with other existing and emerging intersecting European Union legislation, such as the Floods Directive (FD). The WFD is driven largely by ecological considerations, whereas the FD and other legislation are more geared towards protecting physical property and mitigating public safety risks. Thus many of the same waterbodies, especially heavily modified waterbodies, arguably have somewhat competing policy objectives put upon them. This paper explores the means by which Ireland might best achieve the highest degrees of cost effectiveness, economic efficiency and institutional durability in pursuing the common and overarching objective of the WFD and FD - to ensure Irish waterways are put to their highest valued uses.     

Determination of nitrogen in vegetable oils

Summary Hydrolysis with alcoholic hydrochloric acid quantitatively converts the nitrogen of crude soybean lecithin to a water-dispersible form. This alcoholic-acid hydrolysis also converts the nitrogen in large amounts of crude soybean oil to a water-dispersible form which can then be separated and digested with a minimum amount of sulfuric acid by the Kjeldahl procedure. With careful control of both reagents and blank determinations, as little as 0.1 mg. of nitrogen can be measured with a precision of about 10%. The details of the method are given and it is applied to a series of soybean oils after various treatments and to three kinds of salad oils. Presented by Dr. R. T. Milner of the Northern Regional Research Laboratory at the Spring Meeting of the American Oil Chemists' Society at New Orleans, Louisiana, May 20–22, 1947. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry. Agricultural Research Administration, U. S. Department of Agriculture.     

Influence of an oligodendroglial component on the survival of patients with anaplastic astrocytomas: a report of Radiation Therapy Oncology Group 83-02

PURPOSE: Seven percent of patients with high grade gliomas enrolled in RTOG 83-02 had mixed astrocytoma/oligodenroglial elements on central pathology review. It has often been assumed that the most aggressive histologic component of a tumor determines biologic behavior; however in this trial, the survival of patients who had mixed glioblastomas/oligodenrogliomas was significantly longer than that of patients with pure glioblastomas (GBM). We therefore evaluated the effect of an oligodendroglial component on the survival of patients who had anaplastic astrocytomas (AAF) treated in the same trial. METHODS AND MATERIALS: One hundred nine patients who had AAF and 24 patients with mixed AAF/oligodendrogliomas (AAF/OL) were enrolled in a Phase I/II trial of randomized dose-escalation hyperfractioned radiotherapy plus BCNU. AAF/OL patients were older and more likely to have had more aggressive surgery than AAF patients. Other pretreatment characteristics were balanced between groups, as was assigned treatment. RESULTS: The median survival time for AAF was 3.0 years versus 7.3 years for AAF/OL (p = 0.019). In a multivariate analysis, adjusting for extent of surgical resection and age, an oligodendroglial component was an independent prognostic factor for survival. CONCLUSION: The results support the concept that AAFs with an oligodendroglial component have a better prognosis than pure AAF tumors, similar to the effect seen among patients with glioblastoma multiforme tumors. This better survival outcome should be taken into consideration in the design and stratification of future trials. Additionally, in contrast to patients with GBMs, patients who have AAF/OL have the potential for prolonged survival; therefore, late sequelae of treatment (both radiation and chemotherapy) must be weighed more heavily in the benefits to risks analysis.     

Prediction of rates of freezing, thawing or cooling in solids or arbitrary shape using the finite element method

The finite element method was formulated for the solution of three dimensional heat transfer problems in solids of arbitrary geometry with variable thermal properties. These variable properties can include latent heat effects. The accuracy of the method was tested against available analytical solutions and against experimental data for freezing of regular shapes. The method gave comparable predictions to finite difference methods for similar problems and precision was therefore more limited by the data uncertainties than by the numerical approximations inherent in the method. A simplified formulation investigated gave only slightly reduced accuracy yet much shorter computation times than the general formulation. The computer codes for both formulations are available from the authors.The flexibility of the method allows application to a wide variety of situations. For example, rates of chilling, freezing or thawing food or other solids of any shape under any type of external heat transfer environment can be predicted, heterogeneous composition can be taken into account in these predictions, and simultaneous heat and mass transfer can be considered.     

Degradation of acetic and propionic acids in the methane fermentation

A series of batch digestion experiments was performed to evaluate the effect of elevated acetic acid concentrations on the degradation of propionic acid and vice versa. Flask digesters were incubated at 37°C with acetic and propionic acids added at up to 2000 and 1500 mg 1⁻¹, respectively. It was found that increasing the concentration of either acid from low levels reduced the rate of its utilization and that increasing the acetic acid concentration from 1000 to 2000 mg 1⁻¹ significantly inhibited degradation of propionic acid added at 500 mg 1⁻¹. Good agreement was obtained from fitting the logistic equation to the measured data and between duplicate runs performed within the experiments. The observed inhibition of propionate degradation by acetate confirms several earlier reports of product inhibition in the literature and emphasizes the importance of controlling acid levels in maintaining satisfactory digester operation.     

Fatty acid composition of maturingVernonia anthelmintica (L.) Willd. seeds. dihydroxyoleic acid—A possible precursor of epoxyoleic acid

Quantitative measurements of epoxyoleic acid and co-occurring fatty acids in maturingVernonia anthelmintica (L.) Willd. seeds were made to elucidate partially the mode of epoxyoleic biosynthesis. Free (+)threo-12,13-dihydroxy-cis-9-octadecenoic acid was the major component at an intermediate maturation stage, and is believed to be dehydrated to free epoxyoleic acid before incorporation into glycerides. Presented before the Division of Biological Chemistry, Am. Chem. Soc. meeting in St. Louis, Mo., 1961. A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A.