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Ingestion of foreign objects into turbine engines by vortices

Description: Report presenting an investigation of the ingestion of foreign objects by vortices formed between engine inlet and ground surface using a 5000-pound-thrust axial-flow jet engine. Pebbles were projected into the air by the vortices and were drawn into the engine by the high-velocity inlet-air stream.
Date: February 1955
Creator: Rodert, Lewis A. & Garrett, Floyd B.
Partner: UNT Libraries Government Documents Department

Scientific Considerations of Olestra as a Fat Substitute

Description: Olestra is, a sucrose polyester, a noncaloric fat substitute, made from sucrose and several fatty acid esters. It has been approved by the FDA as a food additive used in preparing low-fat deep-frying foods such as savory snacks. Available literature on olestra was evaluated that had both positive and negative connotations. Clinical trials in numerous species of animals including humans were conducted to determine if olestra would affect the utilization and absorption of macro- and micronutrients; the effects of olestra on growth, reproduction, or its toxicity were also examined. The roles of olestra as a fat substitute, how it could effect on humans and the environment, and the potential impacts from its use in large amounts were assessed. Olestra can be removed from the environment by aerobic bacteria and fungi which may be isolated from activated sludge and soils.
Date: December 1999
Creator: Rattagool, Kullakan
Partner: UNT Libraries

Pediatric feeding disorders: Efficacy of multidisciplinary inpatient treatment of gastrostomy tube dependent children.

Description: Efficacy of multidisciplinary inpatient treatment of feeding disordered children was sought through retrospective chart review of 40 G-tube dependent children ages 22 months to 7 years. Premature births were 55% of the sample ranging from 23 to 36 weeks gestation. The majority of co-occurring medical conditions included congenital anomalies (50%), gastroesophageal reflux disease (25%) and chronic lung disease (25%). Treatment effect analyzed from pre and post treatment measures of oral and G-tube caloric intakes resulted in a significant difference from admission to discharge for both oral intake, t (39) = 5.76, p < 0.001, d = 1.02, and G-tube dependency, t(39) = 10.94, p < 0.001, d = 2.03 with both showing strong treatment effects. Results indicated a highly reliable and valid method of treating severe pediatric feeding disorders.
Date: August 2008
Creator: Cornwell, Sonya
Partner: UNT Libraries


Description: Potential airborne releases of radioactivity from facilities operated for the U. S. Department of Energy at the Savannah River Site could pose significant consequences to the public through the ingestion pathway. The Savannah River National Laboratory has developed a suite of technologies needed to conduct assessments of ingestion dose during emergency response, enabling emergency manager at SRS to develop initial protective action recommendation for state agencies early in the response and to make informed decisions on activation of additional Federal assets that would be needed to support long-term monitoring and assessment activities.
Date: December 11, 2007
Creator: Hunter, C
Partner: UNT Libraries Government Documents Department

Dosimetric Significance of the ICRP's Updated Guidance and Models, 1989-2003, and Implications for U.S. Federal Guidance

Description: Over the past two decades the U.S. Environmental Protection Agency (EPA) has issued a series of Federal guidance documents for the purpose of providing the Federal and State agencies with technical information to assist their implementation of radiation protection programs. Currently recommended dose conversion factors, annual limits on intake, and derived air concentrations for intake of radionuclides are tabulated in Federal Guidance Report No. 11 (FGR 11), published in 1988. The tabulations in FGR 11 were based on dosimetric quantities and biokinetic and dosimetric models of the International Commission on Radiological Protection (ICRP) developed for application to occupational exposures. Since the publication of FGR 11 the ICRP has revised some of its dosimetric quantities and its models for workers and has also developed age-specific models and dose conversion factors for intake of radionuclides by members of the public. This report examines the extent of the changes in the inhalation and ingestion dose coefficients of FGR 11 implied by the updated recommendations of the ICRP, both for workers and members of the public.
Date: September 10, 2003
Creator: Leggett, R.W.
Partner: UNT Libraries Government Documents Department

Modeling the Transport and Chemical Evolution of Onshore and Offshore Emissions and their Impact on Local and Regional Air Quality Using a Variable-Grid-Resolution Air Quality Model

Description: This semiannual report summarizes the research performed from 17 April through 16 October 2004. Major portions of the research in several of the project's current eight tasks have been completed, and the results obtained are briefly presented. We have successfully developed the meteorological inputs using the best possible modeling configurations, resulting in improved representation of atmospheric processes. Ingestion of satellite-derived sea surface temperatures in conjunction with the use of our new surface data assimilation technique have resulted in largely improved meteorological inputs to drive the MAQSIP-VGR. The development of the variable-grid-resolution emissions model, SMOKE-VGR, is also largely complete. We expect to develop the final configuration of the SMOKE-VGR during the upcoming reporting period. We are in the process of acquiring the newly released emissions database and offshore emissions data sets to update our archives. The development of the MAQSIP-VGR has been completed and a test run was performed to ensure the functionality of this air quality model. During the upcoming reporting period, we expect to perform the first MAQSIP-VGR simulations over the Houston-Galveston region to study the roles of the meteorology, offshore emissions, and chemistry-transport interactions that determine the temporal and spatial evolution of ozone and its precursors.
Date: October 16, 2004
Creator: Alapaty, Kiran
Partner: UNT Libraries Government Documents Department

Reliability of Current Biokinetic and Dosimetric Models for Radionuclides: A Pilot Study

Description: This report describes the results of a pilot study of the reliability of the biokinetic and dosimetric models currently used by the U.S. Nuclear Regulatory Commission (NRC) as predictors of dose per unit internal or external exposure to radionuclides. The study examines the feasibility of critically evaluating the accuracy of these models for a comprehensive set of radionuclides of concern to the NRC. Each critical evaluation would include: identification of discrepancies between the models and current databases; characterization of uncertainties in model predictions of dose per unit intake or unit external exposure; characterization of variability in dose per unit intake or unit external exposure; and evaluation of prospects for development of more accurate models. Uncertainty refers here to the level of knowledge of a central value for a population, and variability refers to quantitative differences between different members of a population. This pilot study provides a critical assessment of models for selected radionuclides representing different levels of knowledge of dose per unit exposure. The main conclusions of this study are as follows: (1) To optimize the use of available NRC resources, the full study should focus on radionuclides most frequently encountered in the workplace or environment. A list of 50 radionuclides is proposed. (2) The reliability of a dose coefficient for inhalation or ingestion of a radionuclide (i.e., an estimate of dose per unit intake) may depend strongly on the specific application. Multiple characterizations of the uncertainty in a dose coefficient for inhalation or ingestion of a radionuclide may be needed for different forms of the radionuclide and different levels of information of that form available to the dose analyst. (3) A meaningful characterization of variability in dose per unit intake of a radionuclide requires detailed information on the biokinetics of the radionuclide and hence is not feasible for many ...
Date: October 1, 2008
Creator: Leggett, Richard Wayne; Eckerman, Keith F & Meck, Robert A.
Partner: UNT Libraries Government Documents Department

Serotonin, Norepinephrine, and the Hypothalamic Ventromedial Nucleus: a Proposed Mechanism Mediating Hyperphagia and Obesity

Description: Serotonin has been implicated as a modulator of feeding behavior. This experiment was designed to alter brain serotonin levels through dietary means in hypothalamic ventromedial-lesioned and unlesioned rats. Daily food, water, and animal weights were measured. The purpose was to determine if VMH lesions altered the feeding pattern found in unlesioned rats. Although food intake for tryptophanenriched diets and tryptophan-deficient diets did not differ from their respective control groups, in some cases gross animal weights did differ significantly between experimental and control groups and between lesioned and unlesioned groups. A proposed model explains how a "low" energy signal and a "high" protein signal cycles amino acids through gluconeogenesis to comPensate for an energy deficit.
Date: May 1981
Creator: McDermott, Kathy Howard
Partner: UNT Libraries

Pediatric Feeding Disorders: A Controlled Comparison of Multidisciplinary Inpatient and Outpatient Treatment of Gastrostomy Tube Dependent Children

Description: The efficacy of multidisciplinary inpatient and outpatient treatment for transitioning children with severe pediatric feeding disorders from gastrostomy tube dependency to oral nutrition was investigated utilizing caloric and fluid intakes as an outcome measure. The study involved 29 children ages 12 months to 5 years of age with gastrostomy tube dependency. Treatments were provided by speech therapists, occupational therapist, dietician and psychologist for a 30 day period. Four treatment groups were evaluated and average intakes compared at 4 observation periods including pretreatment, initiation of treatment, completion of treatment at 30 days and 4 month follow-up. Children receiving inpatient treatment for feeding disorders evidenced significant differences in oral caloric intake from pretreatment to discharge than outpatient treatment (p < .01) and wait list control group (p = .04). Oral caloric intake from discharge to 4 month follow up yielded no significant differences indicating treatment gains were maintained. Change in environment and caretaker showed a significant effect for the inpatient group (d = 1.89). Effects of treatment by age and weight at 4 month follow up were also analyzed.
Date: December 2010
Creator: Cornwell, Sonya L.
Partner: UNT Libraries

Role of Parental Anxiety on Pediatric Feeding Disorders

Description: The proposed study examined the relationship between parental anxiety, measured both subjectively (via self-report questionnaires) and objectively (via salivary cortisol) and the child's feeding progress. Children diagnosed with a feeding disorder were recruited with their parents at Our Children's House at Baylor (n=19; 11 females, 8 males). The patients and their parents were housed in the clinic for an eight-week intensive multidisciplinary pediatric feeding disorder treatment program. Calorie intake was recorded daily as outcome measures of treatment progression. Parental anxiety was measured by the Pediatric Inventory for Parents (PIP), state anxiety on the State Trait Anxiety Inventory (STAI), and by salivary cortisol at three different time points. The present study attempted to examine whether parental feeding (phase three of treatment program) would continue to cause a decrease in the child's caloric intake. In averaging ten meals prior to parental feeding in comparison to the average of ten meals following parental feeding, there was no significant difference as measured by a t-test. Paired t-tests examined parental anxiety from time one to time two and found that salivary cortisol increased significantly t(15) = -6.07, p = .000 from Time 1 (M = 2.30, SD = 1.64) to Time 2 (M = 5.24, SD = 2.58). This demonstrated that while parental anxiety increased as measured by salivary cortisol, the children continued to make improvements. This may be the result of the multidisciplinary feeding program which encompassed a strong behavioral component and parent training. Even though the current results did not demonstrate a direct relationship between parental stress and caloric intake, parental stress as measured by salivary cortisol did increase.
Date: May 2009
Creator: Didehbani, Nyaz
Partner: UNT Libraries

A fugacity-based indoor residential pesticide fate model

Description: Dermal and non-dietary pathways are potentially significant exposure pathways to pesticides used in residences. Exposure pathways include dermal contact with residues on surfaces, ingestion from hand- and object-to-mouth activities, and absorption of pesticides into food. A limited amount of data has been collected on pesticide concentrations in various residential compartments following an application. But models are needed to interpret this data and make predictions about other pesticides based on chemical properties. In this paper, we propose a mass-balance compartment model based on fugacity principles. We include air (both gas phase and aerosols), carpet, smooth flooring, and walls as model compartments. Pesticide concentrations on furniture and toys, and in food, are being added to the model as data becomes available. We determine the compartmental fugacity capacity and mass transfer-rate coefficient for wallboard as an example. We also present the framework and equations needed for a dynamic mass-balance model.
Date: June 1, 2002
Creator: Bennett, Deborah H.; Furtaw, Edward J. & McKone, Thomas E.
Partner: UNT Libraries Government Documents Department

Uncertainties in Cancer Risk Coefficients for Environmental Exposure to Radionuclides. An Uncertainty Analysis for Risk Coefficients Reported in Federal Guidance Report No. 13

Description: Federal Guidance Report No. 13 (FGR 13) provides risk coefficients for estimation of the risk of cancer due to low-level exposure to each of more than 800 radionuclides. Uncertainties in risk coefficients were quantified in FGR 13 for 33 cases (exposure to each of 11 radionuclides by each of three exposure pathways) on the basis of sensitivity analyses in which various combinations of plausible biokinetic, dosimetric, and radiation risk models were used to generate alternative risk coefficients. The present report updates the uncertainty analysis in FGR 13 for the cases of inhalation and ingestion of radionuclides and expands the analysis to all radionuclides addressed in that report. The analysis indicates that most risk coefficients for inhalation or ingestion of radionuclides are determined within a factor of 5 or less by current information. That is, application of alternate plausible biokinetic and dosimetric models and radiation risk models (based on the linear, no-threshold hypothesis with an adjustment for the dose and dose rate effectiveness factor) is unlikely to change these coefficients by more than a factor of 5. In this analysis the assessed uncertainty in the radiation risk model was found to be the main determinant of the uncertainty category for most risk coefficients, but conclusions concerning the relative contributions of risk and dose models to the total uncertainty in a risk coefficient may depend strongly on the method of assessing uncertainties in the risk model.
Date: January 1, 2007
Creator: Pawel, David; Leggett, Richard Wayne; Eckerman, Keith F & Nelson, Christopher
Partner: UNT Libraries Government Documents Department

Recommended ALIs and DACs for 10 CFR part 220: A consistent numerical set

Description: Appendix B to 10 CFR Part 20 contains numerical data for controlling the intake of radionuclides in the workplace or in the environment. These data, derived from the recommendations of the International Commission on Radiological Protection (ICRP), do not provide a numerically consistent basis for demonstrating compliance with the limitation on dose stated in the regulation. This situation is largely a consequence of the numerical procedures used by the ICRP which did not maintain, in a strict numerical sense, the hierarchial relationship among the radiation protection quantities. In this work recommended values of the quantities in Appendix B to CFR Part 20 are developed using the dose coefficients of the applicable ICRP publications and a numerical procedure which ensures that the tabulated quantities are numerically consistent.
Date: May 1, 1996
Creator: Eckerman, K.F.
Partner: UNT Libraries Government Documents Department

Toxicological Benchmarks for Wildlife

Description: Ecological risks of environmental contaminants are evaluated by using a two-tiered process. In the first tier, a screening assessment is performed where concentrations of contaminants in the environment are compared to no observed adverse effects level (NOAEL)-based toxicological benchmarks. These benchmarks represent concentrations of chemicals (i.e., concentrations presumed to be nonhazardous to the biota) in environmental media (water, sediment, soil, food, etc.). While exceedance of these benchmarks does not indicate any particular level or type of risk, concentrations below the benchmarks should not result in significant effects. In practice, when contaminant concentrations in food or water resources are less than these toxicological benchmarks, the contaminants may be excluded from further consideration. However, if the concentration of a contaminant exceeds a benchmark, that contaminant should be retained as a contaminant of potential concern (COPC) and investigated further. The second tier in ecological risk assessment, the baseline ecological risk assessment, may use toxicological benchmarks as part of a weight-of-evidence approach (Suter 1993). Under this approach, based toxicological benchmarks are one of several lines of evidence used to support or refute the presence of ecological effects. Other sources of evidence include media toxicity tests, surveys of biota (abundance and diversity), measures of contaminant body burdens, and biomarkers. This report presents NOAEL- and lowest observed adverse effects level (LOAEL)-based toxicological benchmarks for assessment of effects of 85 chemicals on 9 representative mammalian wildlife species (short-tailed shrew, little brown bat, meadow vole, white-footed mouse, cottontail rabbit, mink, red fox, and whitetail deer) or 11 avian wildlife species (American robin, rough-winged swallow, American woodcock, wild turkey, belted kingfisher, great blue heron, barred owl, barn owl, Cooper's hawk, and red-tailed hawk, osprey) (scientific names for both the mammalian and avian species are presented in Appendix B). [In this document, NOAEL refers to both dose (mg contaminant per ...
Date: January 1, 1993
Creator: Sample, B.E. Opresko, D.M. Suter, G.W.
Partner: UNT Libraries Government Documents Department

Development of an Ingestion Pathway Model for AXAIRQ

Description: AXAIRQ is a dose mode code used for prospective accident assessment at the Savannah River Site and is primarily used to show regulatory compliance. For completeness of pathway analysis, an ingestion model, AXINGST, has been developed for use with, and incorporation in, AXAIRQ. Currently available ingestion models were referenced as a basis for AXINGST. AXINGST calculates a conservative ingestion dose following an atmospheric release of radionuclides and includes site specific variables where applicable.
Date: January 13, 1999
Creator: Simpkins, A. A.
Partner: UNT Libraries Government Documents Department