Coal Combustion Waste Disposal Facility Design: Electric Power Cooperative Selby, South Dakota

A rural electric cooperative (REC) proposes to build a 700 megawatt (MW) coal fired base load electrical generating station in north-central South Dakota. The plant would consist of a supercritical pulverized coal boiler and a steam turbine generator. Solid wastes generated through the operation of the boiler and associated plant air pollution control systems would be disposed at an onsite landfill. A 202-acre landfill with 10 percent slopes is proposed to manage approximately 685 tons of waste each day; a design capacity of 15,000,000 yd3 is required for the anticipated 50-year life of the facility. The objective of this report is to provide an engineering design for a solid waste landfill that is environmentally sound and economically feasible. The design considers project site background information (soil, geology, and climate) and the regulatory requirements set forth in the State of South Dakota solid waste management rules. A variety of landfill liner, leachate collection, and cover system options were evaluated using the US EPA Hydrologic Evaluation of Landfill Performance (HELP) model. The HELP computer program is a hydrologic model of water movement across, into, through and out of landfills. A 24 in. thick compacted clay liner (CCL), a 48 in. thick CCL, and a composite liner consisting of a 60 mil high density polyethylene (HDPE) geomembrane overlying a compacted soil layer were evaluated with and without a leachate collection system. Two cover systems were evaluated to predict the performance of the closed landfill. Again, the HELP model was used to determine the predicted seepage rate through both 36 in. thick and 48 in. thick landfill cover systems and through the entire landfill. An economic evaluation of the various design options is also provided. The recommended design includes a 48 in. thick composite cover system and a 24 in. thick CCL bottom liner at a total estimated cost of $41,301 per acre. At present, no site specific hydrogeologic information is available; important characteristics such as hydraulic conductivity and hydraulic gradient are not known. Calculations using a range of aquifer parameters and the gradients were completed to provide an envelope of contaminant travel time values. The US EPA Optimal Well Locator (OWL) program was used to account for the effects of dispersion in determining the lateral spacing of wells. Based on the hypothetical landfill layout and groundwater flow regime depicted in this design study, the recommended monitoring network for the 202-acre site consists of 16 wells. Six wells would be either up- or side-gradient, while ten wells would be positioned downgradient. Downgradient wells would have a lateral spacing of approximately 70 m and would be located a maximum of 25 m from the landfill boundary. Calcium, sodium, boron, sulfate, bicarbonate and chloride are recommended as indicator parameters for the long-term monitoring of groundwater at the facility

Salinity, radon, and radon precursors in the soils of Grand Forks County, North Dakota

High levels of indoor radon have been observed in many areas of the Red River Valley and particularly in Grand Forks County of North Dakota. Data from the University of North Dakota (UND) Radon Monitoring Facility indicated more than 80% of the dwellings tested had radon levels greater than the United States Environmental Protection Agency (USEPA) action limit of 4 pCi/l. High radon levels may pose a health threat (USEPA, 1986) to valley residents. A review of existing data indicates that areas of the Red River Valley in North Dakota with elevated soil salinity also exhibit higher equivalent uranium (eU) concentrations than soils of lesser salinity. This study examined relationship between soil salinity, radon precursors, radon, and radon progeny in Grand Forks County, North Dakota. Approximately 75 soil-gas samples collected in Grand Forks County were analyzed for radon-222 using in an alpha particle scintillation counter. Radon concentrations observed in the soil gas samples ranged from about 200 to 1700 pCi/l. In addition to the soil gas samples, continuous soil samples were taken from approximately 0-1 meter and 1-2 meters at the location of each soil gas sample. Ninety-two soil samples were analyzed for uranium by fluorimetry, equivalent uranium (eU) by gamma-ray spectrometry, and for soil salinity. Equivalent uranium, equivalent thorium, potassium-40, and derivative maps were produced using aerial γ-ray data collected during the National Uranium Resource Evaluation (NURE) program in 1979. These maps, when compared to soil survey maps, show several similarities. Areas mapped as saline soils and nearby non-saline soils typically exhibit higher γ-radiation intensities than surrounding areas. Radon concentrations observed in the field appear to be consistent with concentrations predicted by calculations using NURE eU values. Results suggest that radium-226 is preferentially transported in the saline groundwater that is discharged from bedrock aquifers in Grand Forks County. Radium appears to be more soluble in water with high dissolved solids. In an aquifer with high dissolved solids water, competition for the few available sorption sites is high, and radium solubility is enhanced (Michel, 1990). The bedrock aquifers that discharge to the surface in Grand Forks County have total dissolved solids (TDS) values ranging from 4,000 to 10,000 parts-per-million (ppm); thus, it may be reasonable to expect that radium transport could occur under such conditions

A study of all-fluid, high-temperature-sensing probes

Fluidics concept applied to miniaturized all-fluid high temperature sensing probes for use in hypervelocity wind tunnel

Sequence-Dependent Fluorescence of Cyanine Dyes on Microarrays

Cy3 and Cy5 are among the most commonly used oligonucleotide labeling molecules. Studies of nucleic acid structure and dynamics use these dyes, and they are ubiquitous in microarray experiments. They are sensitive to their environment and have higher quantum yield when bound to DNA. The fluorescent intensity of terminal cyanine dyes is also known to be significantly dependent on the base sequence of the oligonucleotide. We have developed a very precise and high-throughput method to evaluate the sequence dependence of oligonucleotide labeling dyes using microarrays and have applied the method to Cy3 and Cy5. We used light-directed in-situ synthesis of terminally-labeled microarrays to determine the fluorescence intensity of each dye on all 1024 possible 5′-labeled 5-mers. Their intensity is sensitive to all five bases. Their fluorescence is higher with 5′ guanines, and adenines in subsequent positions. Cytosine suppresses fluorescence. Intensity falls by half over the range of all 5-mers for Cy3, and two-thirds for Cy5. Labeling with 5′-biotin-streptavidin-Cy3/-Cy5 gives a completely different sequence dependence and greatly reduces fluorescence compared with direct terminal labeling

Global variation in diabetes diagnosis and prevalence based on fasting glucose and hemoglobin A1c

Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) are both used to diagnose diabetes, but these measurements can identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening, had elevated FPG, HbA1c or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardized proportion of diabetes that was previously undiagnosed and detected in survey screening ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the age-standardized proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c was more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global shortfall in diabetes diagnosis and surveillance

Worldwide trends in underweight and obesity from 1990 to 2022: a pooled analysis of 3663 population-representative studies with 222 million children, adolescents, and adults

Background Underweight and obesity are associated with adverse health outcomes throughout the life course. We estimated the individual and combined prevalence of underweight or thinness and obesity, and their changes, from 1990 to 2022 for adults and school-aged children and adolescents in 200 countries and territories. Methods We used data from 3663 population-based studies with 222 million participants that measured height and weight in representative samples of the general population. We used a Bayesian hierarchical model to estimate trends in the prevalence of different BMI categories, separately for adults (age ≥20 years) and school-aged children and adolescents (age 5–19 years), from 1990 to 2022 for 200 countries and territories. For adults, we report the individual and combined prevalence of underweight (BMI <18·5 kg/m2) and obesity (BMI ≥30 kg/m2). For schoolaged children and adolescents, we report thinness (BMI <2 SD below the median of the WHO growth reference) and obesity (BMI >2 SD above the median). Findings From 1990 to 2022, the combined prevalence of underweight and obesity in adults decreased in 11 countries (6%) for women and 17 (9%) for men with a posterior probability of at least 0·80 that the observed changes were true decreases. The combined prevalence increased in 162 countries (81%) for women and 140 countries (70%) for men with a posterior probability of at least 0·80. In 2022, the combined prevalence of underweight and obesity was highest in island nations in the Caribbean and Polynesia and Micronesia, and countries in the Middle East and north Africa. Obesity prevalence was higher than underweight with posterior probability of at least 0·80 in 177 countries (89%) for women and 145 (73%) for men in 2022, whereas the converse was true in 16 countries (8%) for women, and 39 (20%) for men. From 1990 to 2022, the combined prevalence of thinness and obesity decreased among girls in five countries (3%) and among boys in 15 countries (8%) with a posterior probability of at least 0·80, and increased among girls in 140 countries (70%) and boys in 137 countries (69%) with a posterior probability of at least 0·80. The countries with highest combined prevalence of thinness and obesity in school-aged children and adolescents in 2022 were in Polynesia and Micronesia and the Caribbean for both sexes, and Chile and Qatar for boys. Combined prevalence was also high in some countries in south Asia, such as India and Pakistan, where thinness remained prevalent despite having declined. In 2022, obesity in school-aged children and adolescents was more prevalent than thinness with a posterior probability of at least 0·80 among girls in 133 countries (67%) and boys in 125 countries (63%), whereas the converse was true in 35 countries (18%) and 42 countries (21%), respectively. In almost all countries for both adults and school-aged children and adolescents, the increases in double burden were driven by increases in obesity, and decreases in double burden by declining underweight or thinness. Interpretation The combined burden of underweight and obesity has increased in most countries, driven by an increase in obesity, while underweight and thinness remain prevalent in south Asia and parts of Africa. A healthy nutrition transition that enhances access to nutritious foods is needed to address the remaining burden of underweight while curbing and reversing the increase in obesit

Global variations in diabetes mellitus based on fasting glucose and haemogloblin A1c

Fasting plasma glucose (FPG) and haemoglobin A1c (HbA1c) are both used to diagnose diabetes, but may identify different people as having diabetes. We used data from 117 population-based studies and quantified, in different world regions, the prevalence of diagnosed diabetes, and whether those who were previously undiagnosed and detected as having diabetes in survey screening had elevated FPG, HbA1c, or both. We developed prediction equations for estimating the probability that a person without previously diagnosed diabetes, and at a specific level of FPG, had elevated HbA1c, and vice versa. The age-standardised proportion of diabetes that was previously undiagnosed, and detected in survey screening, ranged from 30% in the high-income western region to 66% in south Asia. Among those with screen-detected diabetes with either test, the agestandardised proportion who had elevated levels of both FPG and HbA1c was 29-39% across regions; the remainder had discordant elevation of FPG or HbA1c. In most low- and middle-income regions, isolated elevated HbA1c more common than isolated elevated FPG. In these regions, the use of FPG alone may delay diabetes diagnosis and underestimate diabetes prevalence. Our prediction equations help allocate finite resources for measuring HbA1c to reduce the global gap in diabetes diagnosis and surveillance.peer-reviewe