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The highly reducing chemical environments within coastal marsh soils provide favorable conditions for pyrite (FeS) formation. However, when exposed and oxidized, pyrite can bring about adverse effects by creating extremely acidic conditions within the marsh ecosystem. Therefore, evidence of pyrite formation within these marshes would caution against dredging activities in these areas and should be considered when making land management decisions. This study investigated saline and brackish marsh types within the Barataria Bay basin located in Lafourche Parish, Louisiana. Previous studies, based on such indirect biogeochemical approaches as Fe-based methods and sulfur speciation, have determined the presence of pyrite in these marsh soils. In this study, we used scanning electron microscopy and X-ray diffraction (XRD) to find pyrite crystals in marsh soils as evidence of pyrite formation in the coastal marshes. Pyrite framboids (6 to 8 μm diameter) were found within saline marsh soils. Pyrite crystals were found in close association with organic material. The XRD analysis confirmed the presence of pyrite in both saline and brackish marsh samples. The differential X-ray diffraction (DXRD) patterns revealed that pyrite crystals were more abundant within the coarser soil fraction (2-20 μm) compared with the finer soil fraction (

The study of nitrogen (NH{sub 4}{sup +}) diagenesis associated with hydrocarbon occurrences is intended to aid in predicting favorable areas of petroleum exploration and recovery by establishing a better understanding of the interaction of organic maturation products with clastic sedimentary sequences. This research has indicated that fixed-NH{sub 4} in clays preserves anomalous NH{sub 4}{sup +} abundances, thus recording a significant reaction in the maturation of hydrocarbons which correlates with the oil window. Fixed-NH{sub 4} concentrations are independent of total organic carbon content, but increase with organic maturity in source rocks (up to T{approx}140 C). The authors have found anomalously high fixed-NH{sub 4} concentrations in oil and gas reservoirs, and in sandstones that may have acted as migration conduits for a nearby oilfield. The remainder of the project period will be spent completing publications, and finalizing the interpretation of results on fixed-NH{sub 4} in the Salton Sea (SSDP) and Monterey Fm. The data that authors have collected from these areas will allow them to examine the effect of high temperatures and high-N organic matter (prevalent on the west coast) on levels of NH{sub 4}-fixation. The authors will also develop some preliminary ideas on the mechanism of NH{sub 4}{sup +} oxidation responsiblemore » for high-N{sub 2} (gas) reservoirs such as Sorrento Field, Colorado.« less

Phenotype and gene frequencies are presented for eight polymorphic systems among the Nubians of South Egypt, namely, acid phosphatase, glucose-6-phosphate dehydrogenase, adenylate kinase, 6-phosphogluconate dehydrogenase, esterase D, phosphoglucomutase I, peptidase A, and haptoglobin. Eleven systems, namely, albumin, ceruloplasmin, hemoglobin, lactate dehydrogenase, isocitrate dehydrogenase, phosphohexose isomerase, malate dehydrogenase, peptidase B and C, phosphoglucomutase II, and transferrin were found to be monomorphic. A single electrophoretic variant of phosphohexose isomerase were observed.

The sensitivity and specificity of isoelectric focusing (IEF) and immunoblotting have been combined for the routine typing of the plasma protein alpha-1 acid glycoprotein (Orosomucoid, ORM). Optimized conditions have been determined for a reliable classification of different ORM phenotypes. Phenotypic patterns of ORM in simple IEF gels correspond to those observed by other techniques. Addition of 6 M urea in a thin-layer IEF gel revealed additional, informative microheterogeneity in the ORM system, which cannot be detected in simple IEF gels. Applying the improved method, 239 White and 181 Black Americans have been screened to determine the distribution of ORM allele frequencies. Two common alleles, ORM*1 and ORM*2, have been observed and their frequencies are 0.5592 and 0.4408, and 0.6160 and 0.3840 in Whites and Blacks, respectively. Family studies confirm the genetic basis of this variation which is compatible with autosomal, codominant inheritance.