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Time-windows-based filtering method for near-surface detection of leakage from geologic carbon sequestration sites

Description: We use process-based modeling techniques to characterize the temporal features of natural biologically controlled surface CO{sub 2} fluxes and the relationships between the assimilation and respiration fluxes. Based on these analyses, we develop a signal-enhancing technique that combines a novel time-window splitting scheme, a simple median filtering, and an appropriate scaling method to detect potential signals of leakage of CO{sub 2} from geologic carbon sequestration sites from within datasets of net near-surface CO{sub 2} flux measurements. The technique can be directly applied to measured data and does not require subjective gap filling or data-smoothing preprocessing. Preliminary application of the new method to flux measurements from a CO{sub 2} shallow-release experiment appears promising for detecting a leakage signal relative to background variability. The leakage index of ?2 was found to span the range of biological variability for various ecosystems as determined by observing CO{sub 2} flux data at various control sites for a number of years.
Date: February 28, 2010
Creator: Pan, L.; Lewicki, J.L.; Oldenburg, C.M. & Fischer, M.L.
Partner: UNT Libraries Government Documents Department

Measurement of background translocation frequencies in individuals with clones

Description: In the leukemia case the unseparated B and T lymphocytes had a high translocation frequency even after 0.0014, respectively. After purging all clones from the data, the translocation frequencies for Bio 8 and Bio 23 were 0.00750.0014 and 0.0073 metaphases were scored for chromosomal aberrations,, specifically reciprocal translocations, using fluorescence in situ hybridization (FISH). Metaphase spreads were used from two healthy, unexposed individuals (not exposed to radiation, chemotherapy or radiotherapy) and one early B- precursor acute lymphocytic leukemia (ALL) patient (metaphase spreads from both separated T lymphocytes and unseparated B and T lymphocytes were scored). All three individuals had an abnormally high translocation frequency. The high translocation frequencies resulted from clonal expansion of specific translocated chromosomes. I show in this thesis that by purging (discounting or removing) clones from the data of unexposed individuals, one can obtain true background translocation frequencies. In two cases, Bio 8 and Bio 23, the measured translocation frequency for chromosomes 1, 2 and 4 was 0.0124 purging all of the clones from the data. This high translocation frequency may be due to a low frequency of some clones and may not be recognized. The separated T lymphocytes had a higher translocation frequency than expected.
Date: August 1, 1996
Creator: Wade, M.J.
Partner: UNT Libraries Government Documents Department

A test of aquatic macroinvertebrate sub-sampling using a gridded screen

Description: The Biological Resource Evaluations Team of Los Alamos National Laboratories assessed the reliability of a gridded screen sub-sampling technique to estimate aquatic macroinvertebrates in total samples. Benthic macroinvertebrates were collected by kick sampling three riffles areas in Guaje Canyon, Los Alamos County, New Mexico during July and August, 1994. The study included 4,144 macroinvertebrates from samples consisting of 442 to 1005 individuals. The entire samples were spread onto a gridded screen, and 100 macroinvertebrates were randomly selected for identification. To simplify the results, identified macroinvertebrates were assigned to one of six categories: plecoptera, ephemeroptera, trichoptera, coleoptera, diptera, and non-insects. Three sub-samples were taken from each of six full samples. These counts were used as predicted values, while the total sample counts were used as actual values. Single-factor ANOVA tests showed no significant differences between predicted to actual (PTA) values. However, PTA differences indicated that lab-sorting was a more reliable method than live-sorting without a narcotizing agent. Large samples and large numbers in macroinvertebrate categories were tentatively linked with greater PTA differences. PTA differences were less than 5% in 80% of our trials and less than 10% in 95% of our trials. Despite the relatively small size of sub-samples, sub-samples included 60% of taxa found in the total samples. This sub-sampling technique provides accurate estimates of total sample composition in stream reaches rich enough to easily yield the required 100 individuals.
Date: December 31, 1994
Creator: Cross, S. P.
Partner: UNT Libraries Government Documents Department

Rates of ingestion and their variability between individual calanoid copepods: Direct observations

Description: The goals of this study were to determine rates of ingestion and fecal pellet release, and their variability, for individual planktonic copepods over extended periods of time (>20 min). Ingestions and rejections of individual cells of the diatom Thalassiosira eccentrica by a adult females of the calanoid Paracalanus aculeatus were directly quantified by observing individual copepods continuously at cell concentrations ranging from 0.1 to 1.2 mm{sup 3} l{sup {minus}1}. Average ingestion rates increased with increasing food concentration, but were not significantly different between 0.3 and 1.0 mm{sup 3} l{sup {minus}1} (9.8 and 32.7 {mu}g Cl{sup {minus}1}) of T.eccentrica. Rates of cell rejections were low and similar at 0.1 and 0.3. but were significantly higher at 1.0 mm{sup 3} l{sup {minus}1}. The coefficients of variation for average ingestion rates of individual copepods hardly differed between food concentrations, ranging from 17 to 22%, and were close to those for average fecal pellet release intervals which ranged from 15 to 21%. A comparison between individuals at each food concentration found no significant differences at 1.0; at 0.1 and 0.3 mm{sup 3} l{sup {minus}1}, respectively, ingestion rates of four out of five females did not differ significantly from each other. Average intervals between fecal pellet releases were similar at 0.3 and 1.0 mm{sup 3} l{sup {minus}1}. Fecal pellet release intervals between individuals were significantly different at each food concentration; these significant differences were attributed to rather narrow ranges of pellet release intervals of each individual female. Potential sources/causes of variability in the sizes and rates of copepods in the ocean are evaluated.
Date: December 1, 1995
Creator: Paffenhoefer, G.A.; Lewis, K.D.; Bundy, M.H. & Metz, C.
Partner: UNT Libraries Government Documents Department

Recent developments in ecological theory: hierarchy and scale

Description: Over the past decade, hierarchy and scale have been adopted as an ecological paradigm. Beyond this new awareness, however, a number of studies have attempted to test the underlying hierarchy theory and developed new analytical applications. The purpose of the present paper is to review these recent developments. Tests of the theory have focused on the prediction that ecological systems should not be uniformly distributed across scale, but grouped or lumped into discrete levels. The predicted breaks in spatial distribution have been found in vegetation transects. Vertebrate weight distributions are also distinctly aggregated, corresponding to the spatial scale at which each species operates. An important development of hierarchy theory has considered extrapolating information upscale. Simply stated, the dynamics of the higher level cannot be represented by the same functional form as its components. One cannot insert the mean parameter value for the components and predict higher level effects. Analytical methods, derived from hierarchy theory, have been developed deal with the problem.
Date: December 31, 1995
Creator: O`Neill, R.V.
Partner: UNT Libraries Government Documents Department

Cycle pattern of a R allelic variation. Progress report, 1 November 1978-31 January 1980

Description: Two R alleles vary in cycle fashion. The original, intensely pigmenting forms change to weakly acting ones which revert in turn to the original. Neither direction of change is correlated with recombination of flanking markers. The reversion frequencies do not differ from the respective frequencies of change in the forward direction. The changes are restricted in the life cycle to about the time of meiosis. Modifying tthe incidence of crossing over in the R region altered the frequency of reversion proportionately. These features of instability could result from switching by intrachromosomal recombination between alternative arrangements of an R segment associated with an inverted duplication.
Date: January 1, 1980
Creator: Kermicle, J.L.
Partner: UNT Libraries Government Documents Department

Characterization of a putative S-locus encoded receptor protein kinase and its role in self-incompatibility. Progress report

Description: The major results of our research effort include the determination of the S-Receptor Kinase (SRK) gene structure, the demonstration of S-haplotype-associated SRK polymorphisms and possible co-evolution of SRK and SLG, the characterization of the temporal and spatial expression patterns of SRK, and the demonstration that SRK has intrinsic serine/threonine kinase activity. Our results have indicated that SLG originated from an SRK-like gene by a gene duplication event and suggested a possible molecular basis for leaky S haplotypes. The data have allowed us to develop a model of self-incompatibility based on the interaction of SRK and SLG and the activation of SRK in response to self-pollination. More generally, the information that we have obtained is potentially relevant to understanding mechanisms of signalling inplants. Thus, the interaction of membrane-based receptor protein kinases with secreted forms of their extracellular domains may represent a generalized mechanism by which receptors signal across the plant cell wall.
Date: May 1, 1994
Creator: Nasrallah, J. B.
Partner: UNT Libraries Government Documents Department

Visualization of monoamine oxidase in human brain

Description: Monoamine oxidase is a flavin enzyme which exists in two subtypes, MAO A and MAO B. In human brain MAO B predominates and is largely compartmentalized in cell bodies of serotonergic neurons and glia. Regional distribution of MAO B was determined by positron computed tomography with volunteers after the administration of deuterium substituted [11C]L-deprenyl. The basal ganglia and thalamus exhibited the greatest concentrations of MAO B with intermediate levels in the frontal cortex and cingulate gyrus while lowest levels were observed in the parietal and temporal cortices and cerebellum. We observed that brain MAO B increases with are in health normal subjects, however the increases were generally smaller than those revealed with post-mortem studies.
Date: December 31, 1996
Creator: Fowler, J.S.; Volkow, N.D.; Wang, G.J.; Pappas, N.; Shea, C.; MacGregor, R.R. et al.
Partner: UNT Libraries Government Documents Department

Addendum to the 1996 Gunnison Monitoring Report for the Gunnison, Colorado Wetlands Mitigation Plan

Description: This document is an addendum to the 1996 Gunnison Monitoring Report for the Gunnison, Colorado, Wetlands Mitigation Report, dated July 1997. The purpose of this addendum is to: (1) modify how information on plant height and plant species criteria are presented; and (2) provide more detailed information regarding the evaluation of the bare ground criteria at the Camp Ketle site. The information in this addendum is provided at the request of the Bureau of Land Management to aid in future monitoring and evaluation of the wetland mitigation sites.
Date: October 1, 1997
Partner: UNT Libraries Government Documents Department

Report on the biological monitoring program for Bear Creek at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee, 1989-1994

Description: The Bear Creek Valley watershed drains the area surrounding several closed Oak Ridge Y-12 Plant waste disposal facilities. Past waste disposal practices in the Bear Creek Valley resulted in the contamination of Bear Creek and consequent ecological damage. Ecological monitoring by the Biological Monitoring and Abatement Program (BMAP) was initiated in the Bear Creek watershed in May 1984 and continues at present. Studies conducted during the first year provided a detailed characterization of the benthic invertebrate and fish communities in Bear Creek. The initial characterization was followed by a biological monitoring phase in which studies were conducted at reduced intensities.
Date: April 1, 1996
Creator: Hinzman, R.L.; Beauchamp, J.J.; Cada, G.F. & Peterson, M.J.
Partner: UNT Libraries Government Documents Department

Biochemical and biophysical characterization of the major outer surface protein, OSP-A from North American and European isolates of Borrelia burgdorferi

Description: Lyme borreliosis, caused by the spirochete Borrelia burgdorferi, is the most common vector-borne disease in North America and Western Europe. As the major delayed immune response in humans, a better understanding of the major outer surface lipoproteins OspA and OspB are of much interest. These proteins have been shown to exhibit three distinct phylogenetic genotypes based on their DNA sequences. This paper describes the cloning of genomic DNA for each variant and amplification of PCR. DNA sequence data was used to derive computer driven phylogenetic analysis and deduced amino acid sequences. Overproduction of variant OspAs was carried out in E. coli using a T7-based expression system. Circular dichroism and fluorescence studies was carried out on the recombinant B31 PspA yielding evidence supporting a B31 protein containing 11% alpha-helix, 34% antiparallel beta-sheet, 12% parallel beta sheet.
Date: December 31, 1995
Creator: McGrath, B.C.; Dunn, J.J.; France, L.L.; Jaing, W.; Polin, D.; Gorgone, G. et al.
Partner: UNT Libraries Government Documents Department

Uncertainties in Organ Burdens Estimated from PAS

Description: To calculate committed effective dose equivalent, one needs to know the quantity of the radionuclide in all significantly irradiated organs (the organ burden) as a function of time following the intake. There are two major sources of uncertainty in an organ burden estimated from personal air sampling (PAS) data: (1) The uncertainty in going from the exposure measured with the PAS to the quantity of aerosol inhaled by the individual, and (2) The uncertainty in going from the intake to the organ burdens at any given time, taking into consideration the biological variability of the biokinetic models from person to person (interperson variability) and in one person over time (intra-person variability). We have been using biokinetic modeling methods developed by researchers at the University of Florida to explore the impact of inter-person variability on the uncertainty of organ burdens estimated from PAS data. These initial studies suggest that the uncertainties are so large that PAS might be considered to be a qualitative (rather than quantitative) technique. These results indicate that more studies should be performed to properly classify the reliability and usefulness of using PAS monitoring data to estimate organ burdens, organ dose, and ultimately CEDE.
Date: February 2, 2004
Creator: La Bone, T.R.
Partner: UNT Libraries Government Documents Department

Study of mathematical models of mutation and selection in multi-locus systems. Annual progress report, October 1, 1980-September 30, 1981

Description: During the past year, research has been devoted to two related studies of two-locus systems under natural selection and one on selection in haplo-diploid organisms. The principal results are: (1) Numerical studies were made of 2 locus selection models with asymmetric fitnesses. These were created by perturbing the fitness matrices of symmetric models whose results are known analytically. A complete classification of solved models has been made and all perturbations of these have been undertaken. The result is that all models lead to three classes of equilibrium structure. All are characterized by multiple equilbria with small linkage disequilibria under loose linkage and high complementarity equilibria under tight linkage. In some cases there is gene fixation at intermediate linkage. (2) It has been shown that selection may favor more recombination, contrary to the usual expectation, if multiple locus polymorphisms are maintained by a mechanism other than marginal overdominance. This may be the result of mutation-selection balance or frequency-dependent selection. (3) In a haplo-diploid system in which diploid males are lethal (as in bees and braconid wasps) the number of sex alleles that can be maintained depends both on breeding size and the number of colonies. Simulations show that the steady number is sensitive to the number of colonies but insensitive to the number of matings. Thirty-five to fifty colonies are sufficient to maintain very large numbers of sex alleles.
Date: January 1, 1981
Creator: Lewontin, R C
Partner: UNT Libraries Government Documents Department

Analyses of inter- and intra-patient variation in the V3 loop of the HIV-1 envelope protein

Description: The third hypervariable domain of the HIV-1 gp120 envelope protein (V3) has been the focus of intensive sequencing efforts. To date, nearly one thousand V3 loop sequences have been stored in the HIV sequence database. Studies have revealed that the V3 loop elicits potent type-specific immune responses, and that it plays a significant role in cell tropism and fusion . The immunogenic tip of the loop can serve as a type-specific neutralizing antibody epitope, as well as a cytotoxic T-cell epitope. A helper T-cell epitope that lies within the amino terminal half of the V3 loop has also been characterized. Despite the richness of the immunologic response to this region, its potential for variation makes it an elusive target for vaccine design. Analyses of sibling sequence sets (sets of viral sequences derived from one person) show that multiple forms of the immunogenic tip of the loop are found within most HIV-1 infected individuals. Viral V3 sequences obtained from epidemiologically unlinked individuals from North America and Europe show extensive variation. However, some amino acid positions distributed throughout the V3 loop are highly conserved, and there is also conservation of the charge class of amino acid able to occupy certain positions relative to the tip of the loop. By contrast, the sequences obtained from many countries throughout the African continent reveal that V3 is a remarkably fluid region with few absolute constraints on the nature of the amino acids that can occupy most positions in the loop. The high degree of heterogeneity in this region is particularly striking in view of its contribution to biologically important viral functions.
Date: September 17, 1991
Creator: Korber, B.; Myers, G. & Wolinsky, S.
Partner: UNT Libraries Government Documents Department

Differences in pulmonary responses of rats, other animals, and humans to chronic inhalation of silica and other particles

Description: The pulmonary carcinogenicity of quartz in rats supports the plausibility of silica-induced lung cancer in humans. However, pulmonary responses of rats to dusts differ from those of other rodents, and may differ from those of humans. Dust-exposed rats have a greater propensity than mice or hamsters for epithelial hyperplasia, metaplasia, and fibrosis. Lung tumors occur in rats, but not mice or hamsters, treated with quartz, or exposed chronically to several other dusts. There are few opportunities for directly comparing the susceptibilities of rats and humans to dust-induced lung tumors. Because of the uncertain human responses to silica and many other particles, the negative human lung cancer response to coal dust may provide the best opportunity to calibrate responses of rats against those of humans. Historical dust lung burdens in coal miners were in the range of those associated with carcinogenicity in rats exposed to several dusts, but the carcinogenicity of coal dust in rats is unknown. The usefulness of tumor data from rats for predicting human lung cancer risk from inhaled silica and other dusts remains uncertain.
Date: December 31, 1993
Creator: Mauderly, J. L.
Partner: UNT Libraries Government Documents Department

Alu repeats as markers for forensic DNA analyses

Description: The Human-Specific (HS) subfamily of Alu sequences is comprised of a group of 500 nearly identical members which are almost exclusively restricted to the human genome. Individual subfamily members share an average of 98.9% nucleotide identity with the HS subfamily consensus sequence, and have an average age of 2.8 million years. We have developed a Polymerase Chain Reaction (PCR) based assay using primers complementary to the 5 inch and 3 inch unique flanking DNA sequences from each HS Alu that allow the locus to be assayed for the presence or absence of the Alu repeat. The dimorphic HS Alu sequences probably inserted in the human genome after the radiation of modem humans (within the last 200,000-one million years) and represent a unique source of information for human population genetics and forensic DNA analyses. These sites can be developed into Dimorphic Alu Sequence Tagged Sites (DASTS) for the Human Genome Project. HS Alu family member insertions differ from other types of polymorphism (e.g. Variable Number of Tandem Repeat [VNTR] or Restriction Fragment Length Polymorphism [RFLP]) in that polymorphisms due to Alu insertions arise as a result of a unique event which has occurred only one time in the human population and spread through the population from that point. Therefore, individuals that share HS Alu repeats inherited these elements from a common ancestor. Most VNTR and RFLP polymorphisms may arise multiple times in parallel within a population.
Date: January 1, 1994
Creator: Batzer, M. A.; Alegria-Hartman, M. & Kass, D. H.
Partner: UNT Libraries Government Documents Department

Summer investigations into the metabolic diversity of the microbial world. Progress report, May 5, 1992--April 30, 1993

Description: The philosophy of the course described here is to underscore the essence of microbiology which is diversity>: diversity of morphology and cellular development, behavior, and metabolic and physiological functions. Emphasis is on microbes other than those customarily covered in conventional microbiology courses and includes: the archaebacteria, extremophiles, and array of obligate anaerobes, various phototrophs, and those microbes exhibiting complex developmental cycles. Also included are microbes carrying out a variety of transformations of organic and inorganic compounds, as well as those which normally occur in symbiotic association with other microbes or with higher forms of life.
Date: May 17, 1993
Creator: Breznak, J. & Dworkin, M.
Partner: UNT Libraries Government Documents Department

Molecular genetics of myosin motors in Arabidopsis. Progress report, [July 1, 1992--February 28, 1994]

Description: We have evidence for at least nine myosin-like genes in Arbidopsis, six of which have been cloned by a PCR-based method from genomic DNA, two have been isolated by genomic DNA cloning, and four have been identified by cDNA cloning. Most of our attention has been focused on the four myosin genes for which we have cDNA clones, and these cDNAs have now been sequenced to completion. Each of these myosins is similar in overall structure, with each containing the characteristic myosin head (motor) domain, which possesses ATP- and actin-binding motifs, a series of IQ repeats, which may be involved in calmodulin binding, a domain with a high probability of forming an alpha-helical coiled-coil secondary structure, which may allow the polypeptides to form dimers, and a variable tail domain, which may serve to define the specific cellular component that each myosin interacts with. One of these myosin genes, called MYA1, displays structural similarity to class of myosins that includes the yeast MYO2, mouse Dilute, and chicken p190 proteins, and this group of myosins is thought to play a role in intracellular trafficking of organelles. Because MYA1 is similar to this interesting class of myosins, we have chosen to conduct detailed studies of MYA1.
Date: June 1, 1994
Partner: UNT Libraries Government Documents Department

Variability for Biomass Production and Plant Composition in Sericea Lespedeza Germplasm. Final report on a Field and Laboratory Research Program, September 30, 1990--December 31, 1991

Description: Sericea lespedeza [Lespedeza cuneata] is a deep-rooted legume that can be established successfully on eroded and depleted croplands. It is tolerant of drought, high levels of aluminum, and low soil fertility; environmental conditions found throughout the southeastern region of the USA. Sericea lespedeza is capable of improving soil by increasing its organic matter and nitrogen content rapidly. A field with a four year stand of sericea lespedeza grown for soil conservation or biomass production may have over 7 Mg ha{sup {minus}1} of residues on the surface. Once established, sericea lespedeza maintenance costs are relatively small compared to other plants. While most herbaceous plants require nitrogen fertilization, sericea lespedeza fixes its own. Compared to most other crops, relatively few diseases and insect problems are associated with sericea lespedeza. A field experiment aimed at measuring biomass yield of 81 genotypes of sericea lespedeza over time and variation in biomass composition was conducted. Genotype R194-79-290-9 had the highest mean biomass yield and, consistently, ranked among the top four during the years that this study was conducted. Other genotypes that also had a good performance over the four years are the cultivar Serala and the breeding line 75-2-3. No significant differences were found among genotypes for percentage of crude protein content. There were significant differences among genotypes for neutral detergent fiber, hemicellulose, and holocellulose content. There were not significant differences among genotypes for acid detergent fiber, lignin and cellulose content. Further testing of the best genotypes should be conducted at several locations to determine the genotype to be released for the specific purpose of biomass production. Screening of accessions from the Plant Introduction System should be conducted to determine their variability for lignin and crude protein content.
Date: May 1, 1993
Creator: Mosjidis, J. A.
Partner: UNT Libraries Government Documents Department

Renewable hydrogen production for fossil fuel processing

Description: The objective of this mission-oriented research program is the production of renewable hydrogen for fossil fuel processing. This program will build upon promising results that have been obtained in the Chemical Technology Division of Oak Ridge National Laboratory on the utilization of intact microalgae for photosynthetic water splitting. In this process, specially adapted algae are used to perform the light-activated cleavage of water into its elemental constituents, molecular hydrogen and oxygen. The great potential of hydrogen production by microalgal water splitting is predicated on quantitative measurement of their hydrogen-producing capability. These are: (1) the photosynthetic unit size of hydrogen production; (2) the turnover time of photosynthetic hydrogen production; (3) thermodynamic efficiencies of conversion of light energy into the Gibbs free energy of molecular hydrogen; (4) photosynthetic hydrogen production from sea water using marine algae; (5) the original development of an evacuated photobiological reactor for real-world engineering applications; (6) the potential for using modern methods of molecular biology and genetic engineering to maximize hydrogen production. The significance of each of these points in the context of a practical system for hydrogen production is discussed. This program will be enhanced by collaborative research between Oak Ridge National Laboratory and senior faculty members at Duke University, the University of Chicago, and Iowa State University. The special contribution that these organizations and faculty members will make is access to strains and mutants of unicellular algae that will potentially have useful properties for hydrogen production by microalgal water splitting.
Date: September 1, 1994
Creator: Greenbaum, E.
Partner: UNT Libraries Government Documents Department

Enzymatic studies of radiation damage

Description: Progress is reported on studies related to molecular mechanisms for radiation damage to cells. Mung bean nuclease was shown to excise the A + T rich regions from different species of DNA exposed to premelting temperatures. This suggests an additional application of mung bean nuclease as a means of detection of slightly damaged reglons of DNA. A new sensitive method for the determination of nucleoside monophosphates and nucleoside 3', 5'-diphosphates was developed. The method was applied to the determination of the frequency of nucleosides appearing in the terminal position of an oligonucleotide. An argument serves biological unity of all nucaeases is presented. (auth)
Date: January 1, 1974
Creator: Laskowski, M Sr
Partner: UNT Libraries Government Documents Department