Environmental Engineering Commons^™

Improved Soil Mixing And Delivery System For A Storm Runoff Simulator, William C. Alms, Thomas G. Franti, David P. Shelton

Department of Agricultural and Biological Systems Engineering: Faculty Publications

An earlier version of a storm runoff simulator to test conservation buffers reproduced target hydrographs and sedigraphs using uniform, fine sand; however, it was unable to uniformly mix and deliver native sediment. The objectives of this work reported were to create a method to process native agricultural sediment, mix a uniform sediment slurry at a target concentration, and create a control system that will deliver the slurry in varying flow rates corresponding to a target sedigraph. Eroded silty clay (14% sand) was scraped, dried, and processed with a hammer mill. A sand (93% sand) and loam (44% sand) were dried …

Identification Of Holocarboxylase Synthetase Chromatin Binding Sites In Human Mammary Cell Lines Using The Damid Technology, Dipika Singh, Angela K. Pannier, Janos Zempleni

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Holocarboxylase synthetase (HCS) is a chromatin protein that is essential for mediating the covalent binding of biotin to histones. Biotinylation of histones plays crucial roles in the repression of genes and repeats in the human genome. We tested the feasibility of DNA adenine methyltransferase identification (DamID) technology to map HCS binding sites in human mammary cell lines. Full-length HCS was fused to Dam for subsequent transfection into breast cancer (MCF-7) and normal breast (MCF-10A) cells. HCS docking sites in chromatin were identified by using the unique adenine methylation sites established by Dam in the fusion construct; docking sites were unambiguously …

Flocculation Of Wall-Deficient Cells Of Chlamydomonas Reinhardtii Mutant Cw15 By Calcium And Methanol, Matt Scholz, Takanori Hoshino, Mark R. Riley, Joel Cuello

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Flocculation is a common and inexpensive method for harvesting algae from solution. After nitrogen starvation, it was shown that 83 + 3% of the wall-deficient cells of the cw 15 mutant of Chlamydomonas reinhardtii flocculated from 12 mL samples within 15 min after the addition of 15 mM calcium chloride at pH 8.4. Only 24 2% of the wildtype strain flocculated under these conditions, thus demonstrating how a simple mutation might facilitate process design. The data suggested that algae grown in waters with similar calcium concentrations (e.g. certain wastewaters) might be harvested through simple pH adjustment. It was also discovered …

Performance Of Extended Shuttleworth‐Wallace Model For Estimating And Partitioning Of Evapotranspiration In A Partial Residue‐Covered Subsurface Drip‐Irrigated Soybean Field, Lameck O. Odhiambo, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Estimation of actual evapotranspiration (ET), especially its partitioning into plant transpiration (T) and soil evaporation (E), in agricultural fields is important for effective soil water management and conservation and for understanding the interactions between ET, T, and E with the management practices. Direct field measurements of ET, T, and E rates are difficult and costly; hence, mathematical models are used for estimating them. The objective of this study was to evaluate the practical applicability of the Shuttleworth‐Wallace (S‐W) model to estimate and partition ET in a subsurface drip‐irrigated soybean (Glycine max L. Merr.) field with partial residue cover. While its …

Irrigation Efficiency And Uniformity, And Crop Water Use Efficiency, Suat Irmak, Lameck O. Odhiambo, William L. Kranz, Dean E. Eisenhauer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

This Extension Circular describes various irrigation efficiency, crop water use efficiency, and irrigation uniformity evaluation terms that are relevant to irrigation systems and management practices currently used in Nebraska, in other states, and around the world. The definitions and equations described can be used by crop consultants, irrigation district personnel, and university, state, and federal agency personnel to evaluate how efficiently irrigation water is applied and/or used by the crop, and can help to promote better or improved use of water resources in agriculture.

As available water resources become scarcer, more emphasis is given to efficient use of irrigation water …

A Case Study Concerning The Effects Of Controller Response And Turning Movements On Application Rate Uniformity With A Self-Propelled Sprayer, Joe D. Luck, A. Sharda, Santosh Pitla, J. P. Fulton, S. A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The use of precision agriculture technologies such as automatic boom section control allows producers to reduce off-target application when applying herbicides. While automatic boom section control provides benefits, pressure differences across the spray boom resulting from boom section actuation may lead to off-rate application errors. Off-rate errors may also result from spray rate controller compensation for ground speed changes or velocity variation across the spray boom during turning movements. This project focused on characterizing application rate variation for three fields located in central Kentucky. GPS coordinates, boom control status, and nozzle pressure data (at 15 nozzle locations) were recorded as …

Glypican-3 Targeting Of Liver Cancer Cells Using Multifunctional Nanoparticles, James O. Park, Zachary Stephen, Conory Sun, Omid Veiseh, Forrest M. Kievit, Chen Fang, Matthew Leung, Hyejung Mok, Miqin Zhang

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Imaging is essential in accurately detecting, staging, and treating primary liver cancer (hepatocellular carcinoma [HCC]), one of the most prevalent and lethal malignancies. We developed a novel multifunctional nanoparticle (NP) specifically targeting glypican-3 (GPC3), a proteoglycan implicated in promotion of cell growth that is overexpressed in most HCCs. Quantitative real-time polymerase chain reaction was performed to confirm the differential GPC3 expression in two human HCC cells, Hep G2 (high) and HLF (negligible). These cells were treated with biotin-conjugated GPC3 monoclonal antibody (aGPC3) and subsequently targeted using superparamagnetic iron oxide NPs conjugated to streptavidin and Alexa Fluor 647. Flow cytometry demonstrated …

Cellular Arrays For Large-Scale Analysis Of Transcription Factor Activity, Abigail D. Bellis, Beatriz Peňalver-Bernabé, Michael S. Weiss, Michael E. Yarrington, Maria V. Barbolina, Angela K. Pannier, Jacqueline S. Jeruss, Linda J. Broadbelt, Lonnie D. Shea

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Identifying molecular mechanisms or therapeutic targets is typically based on large-scale cellular analysis that measures the abundance of mRNA or protein; however, abundance does not necessarily correlate with activity. We report a method for direct large-scale quantification of active pathways that employs a cellular array with parallel gene delivery of constructs that report pathway activity. The reporter constructs encode luciferase, whose expression is influenced by binding of transcription factors (TFs), which are the downstream targets of signaling pathways. Luciferase levels are quantified by bioluminescence imaging (BLI), which allows for rapid, noninvasive measurements. Activity profiles by BLI of 32 TFs were …

Microarray Analysis Of Gene Expression Profiles In Cells Transfected With Nonviral Vectors, Sarah A. Plautz, Gina Boanca, Jean-Jack M. Riethoven, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Inefficient gene delivery is a critical factor limiting the use of nonviral methods in therapeutic applications including gene therapy and tissue engineering. There have been few efforts to understand or engineer the molecular signaling pathways that dictate the efficacy of gene transfer. Microarray analysis was used to determine endogenous gene expression profiles modulated during nonviral gene transfer. Nonviral DNA lipoplexes were delivered to HEK 293T cells. Flow cytometry was used to isolate a population of transfected cells. Expression patterns were compared between transfected and nontransfected samples, which revealed three genes that were significantly upregulated in transfected cells, including RAP1A, …

Effects Of Warm-Mix Asphalt Additives On Asphalt Mixture Characteristics And Pavement Performance, Jun Zhang

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The primary objective of this research is to evaluate the feasibility of several WMA mixtures as potential asphalt paving mixtures for Nebraska pavements. To that end, three well-known WMA additives (i.e., Sasobit, Evotherm, and Advera synthetic zeolite) were evaluated. For a more realistic evaluation of the WMA approaches, trial pavement sections of the WMA mixtures and their HMA counterparts were implemented in Antelope County, Nebraska. More than one ton of field-mixed loose mixtures were collected at the time of paving and were transported to the NDOR and UNL laboratories to conduct comprehensive laboratory evaluations and pavement performance predictions of the …

Hydraulic Conductivity, Infiltration, And Runoff From No-Till And Tilled Cropland, Jessica H. Deck

Department of Environmental Engineering: Theses and Other Student Research

Infiltration and runoff are important processes that affect the efficiency of center pivot irrigation systems. No-till planting systems potentially influence the hydraulic properties of soils and the soil surface conditions. The result of long-term use of no-till could be higher infiltration and lower runoff from rainfall and irrigation.

This potential was investigated in Nebraska on two center pivot irrigated sites; Fillmore County and Phelps County, one furrow irrigated site; South Central Agriculture Laboratory (SCAL), and one dryland site; Rogers Farm. Paired treatments were used at each location, one that was no-till planted and one that used two to three operations …

Optimization And Economic Evaluation Of Industrial Gas Production And Combined Heat And Power Generation From Gasification Of Corn Stover And Distillers Grains, Ajay Kumar, Yaşar Demirel, David D. Jones, Milford Hanna

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Thermochemical gasification is one of the most promising technologies for converting biomass into power, fuels and chemicals. The objectives of this study were to maximize the net energy efficiency for biomass gasification, and to estimate the cost of producing industrial gas and combined heat and power (CHP) at a feedrate of 2,000 kg/h. Aspen Plusbased model for gasification was combined with a CHP generation model, and optimized using corn stover and dried distillers grains with solubles (DDGS) as the biomass feedstocks. The cold gas efficiencies for gas production were 57% and 52%, respectively, for corn stover and DDGS. The selling …

Use Of Passive Samplers To Evaluate Pharmaceutical Fate In Surface Waters, Delshawn L. Brown

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Emerging contaminants have been of importance in recent water research. Wastewater treatment plants (WWTPs) have proved ineffective at handling present-day antibiotic loads from hospital and municipal sources. Kolpin et al. (2002) performed a study that identified pharmaceuticals in numerous waters downstream from effluent discharge. Though present in trace levels, concern has been raised regarding pharmaceutical persistence in natural environments. In the present study, uptake rates were quantified in the laboratory for 25 pharmaceutical compounds using Polar Organic Chemical Integrative Samplers (POCIS). Twenty new uptake rates were determined for compounds that have no previously reported literature values. POCIS was also used …

Nebraska Water And Energy Flux Measurement, Modeling, And Research Network (Nebflux), Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Surface energy and water vapor fluxes play a critical role in understanding the response of agro‐ecosystems to changes in environmental and atmospheric parameters. These fluxes play a crucial role in exploring the dynamics of water and energy use efficiencies of these systems. Quantification of the fluxes is also necessary for assessing the impact of land use and management changes on water balances. Accomplishing these goals requires measurement of water vapor and energy exchanges between various vegetation surfaces and microclimates for long‐enough periods to understand the behavior and dynamics involved with the flux transfer so that robust models can be developed …

2010 Nebraska Water Monitoring Programs Report, Marty Link

Nebraska Department of Environmental Quality: Reports

The Nebraska Department of Environmental Quality (NDEQ) is charged with monitoring, assessing, and to the extent possible, managing the state’s water resources. The purpose of this work is to protect and maintain good quality water and encourage or execute activities to improve poor water quality. Monitoring is done on the over 18,000 miles of flowing rivers and streams, our greater than 280,000 acres of surface water in lakes and reservoirs, and the vast storage of groundwater in Nebraska’s aquifers.

Numerically Predicting Seepage Gradient Forces And Erosion: Sensitivity To Soil Hydraulic Properties, Garey A. Fox, Derek M. Heeren, Glenn V. Wilson, E. J. Langendoen, Amanda K. Fox, Maria L. Chu-Agor

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Research has suggested that streambank seepage can be an important mechanism of bank instability; however, limited information is available on the level of soil characterization necessary to accurately predict seepage gradient forces and erosion. The objective of this research was to quantify the expected range of predicted seepage gradients for various degrees of site characterization. Uncertainty analysis on seepage gradient predictions was performed relative to variability in soil hydraulic properties. A two-dimensional unsaturated/saturated groundwater flow model was used to simulate a homogeneous soil layer for sand and loamy sand soils packed at various bulk densities, ρ_b. A pedotransfer …

On The Dynamics Of Canopy Resistance: Generalized Linear Estimation And Relationships With Primary Micrometeorological Variables, Suat Irmak, Denis Mutiibwa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The 1‐D and single layer combination‐based energy balance Penman‐Monteith (PM) model has limitations in practical application due to the lack of canopy resistance (r_c) data for different vegetation surfaces. r_c could be estimated by inversion of the PM model if the actual evapotranspiration (E_Ta) rate is known, but this approach has its own set of issues. Instead, an empirical method of estimating r_c is suggested in this study. We investigated the relationships between primary micrometeorological parameters and rc and developed seven models to estimate r_c for a nonstressed maize canopy on an hourly …

161. The Potential Role Of Extensor Muscle Fatigue In The Onset Of Intervertebral Disc Degeneration: A Novel In Vivo Model, Mary Beth M. Grabowsky, Nicholas A. Pallota, Matthew W. Connelly, Brett Van Etten, Rebecca A. Wachs, Max Alley, Joseph C. Glennon, Andrew H. Dubin, John W. German, Richard L. Uhl, Eric H. Ledet

Department of Agricultural and Biological Systems Engineering: Faculty Publications

BACKGROUND CONTEXT: Occupation is strongly correlated to low back pain (LBP). Specific occupational activities associated with low back pain include poor posture, whole body vibration, and repetitive lifting. These activities have a common link: they result in fatigue of the primary spinal extensor musculature. This fatigue may lead to increased intervertebral loading - a stimulus for disc degeneration. If true, this association could provide a vital connection between detrimental physical activities and LBP. However, the link between muscle fatigue and increased load across the disc space has never been quantified in vivo.

PURPOSE: The purpose of this study was to …

Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. Van Dewalle, William R. Rathje, Rodney Debuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it's approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, …

Nebraska Agricultural Water Management Demonstration Network (Nawmdn): Integrating Research And Extension/Outreach, Suat Irmak, Jennifer M. Rees, Gary L. Zoubek, Brandy S. Van Dewalle, William R. Rathje, Rodney Debuhr, Dan Leininger, Darrel D. Siekman, James W. Schneider, Andrew P. Christiansen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Maximizing the net benefits of irrigated plant production through appropriately designed agricultural water management programs is of growing importance in Nebraska, and other western and Midwestern states, because many areas are involved in management and policy changes to conserve irrigation water. In Nebraska, farmers are being challenged to practice conservation methods and use water resources more efficiently while meeting plant water requirements and maintaining high yields. Another challenge Nebraska experiences in it's approximately 3.5‐million‐ha irrigated lands is limited adoption of newer technologies/tools to help farmers better manage irrigation, conserve water and energy, and increase plant water use efficiency. In 2005, …

Development Of The Mask Scentometer, A Comparison Of Ambient Odor Assessment Methods, And Their Application In Ground Truthing Atmospheric Dispersion Models, Christopher G. Henry

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

This dissertation is organized as four stand-alone papers. Paper No. 1 describes the development of the Mask Scentometer and reports dilution ratios measured during use by twelve different people. Dilution ratios at the Mask Scentometer’s five dilution-to-threshold (D/T) settings were found to be 0.35, 1, 2, 4.5 and 18. In Paper No.’s 2 and 4, ambient odor assessment methods were compared in both controlled laboratory conditions and in the field. Laboratory analysis of ambient air samples using dynamic triangular forced-choice olfactometry (DTFCO) did not correlate well with any of the ambient odor assessment methods. Average intensity-predicted D/T was roughly five …

Nutrient And Bacterial Transport In Runoff From Soil And Pond Ash Amended Feedlot Surfaces, John E. Gilley, Jason R. Vogel, Elaine D. Berry, Roger Eigenberg, David B. Marx, Brian L. Woodbury

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The addition of pond ash (fly ash that has been placed in evaporative ponds and subsequently dewatered) to feedlot surfaces provides a healthier environment for livestock and economic advantages for the feedlot operator. However, the water quality effects of pond ash amended surfaces are not well understood. The objectives of this field investigation were to: (1) compare feedlot soil properties, and nutrient and bacterial transport in runoff, from pond ash amended surfaces and soil surfaces; (2) compare the effects of unconsolidated surface materials (USM) (loose manure pack) and consolidated subsurface materials (CSM) (compacted manure and underlying layers) on nutrient and …

Impact Of Microclimatic Data Measured Above Maize And Grass Canopies On Penman‐Monteith Reference Evapotranspiration Calculations, Suat Irmak, Lameck O. Odhiambo

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Estimation of reference evapotranspiration (ET_ref) using measured microclimatic data and the Penman‐Monteith (PM) method provides a powerful means of quantifying actual plant evapotranspiration (ET_a) needed for use in various disciplines. When applying the PM method to estimate ET_ref, it is desirable to measure the required microclimatic data over a reference grass or alfalfa surface rather than above non‐reference surfaces. However, in reality, establishing and maintaining a reference surface for long periods of time is a difficult task. Other surface energy balance systems, such as the Bowen ratio energy balance system (BREBS), eddy covariance system, …

Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water availability for irrigation throughout the world has been reduced in recent years due to a combination of frequent droughts and competition for water resources among agricultural, industrial, and urban users. In addition, some major agricultural areas face moderate to significant reductions of rainfall, or changes in timing of stream flow due to changes in timing of snowmelt, as a result of global climate change. Under such conditions, sophisticated irrigation water management will be required to optimize water use efficiency and maintain sufficient levels of crop productivity and quality. A key factor to achieve these targets is the estimation of …

Magnitude And Trends Of Reference Evapotranspiration Rates In South Central Nebraska: Daily, Monthly, Growing Season Total, And Annual Total, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Reference evapotranspiration (ET_ref ) is used to determine the actual water use (ET_a) rate for various crops and is one of the key variables that needs to be determined accurately for effective irrigation management. This extension circular provides information on the magnitude and temporal distribution of daily, monthly, annual, and growing season alfalfa-reference evapotranspiration (ET_ref)) in south central Nebraska. It also discusses why long-term average ET_ref values may not represent non-average years or be accurate enough for irrigation management.

The most common way to calculate actual crop water use (ET_a) for a …

Integration Of An Extended Octagonal Ring Transducer And Soil Coulterometer For Identifying Soil Compaction, Santosh Pitla, L. G. Wells, S. A. Shearer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The soil coulterometer is an “on‐the‐go” electro‐mechanical system which collects impedance force data at multiple depths using an oscillating coulter. During the initial testing (summer 2006), only vertical soil impedance force data was collected using a pressure sensor. To improve the performance of the coulterometer, an extended octagonal ring transducer was integrated into the system to collect both the horizontal and vertical impedance forces given by the soil. In the summer of 2007, data was collected using the revised sensor from a typical central Kentucky field setting in a 0.8‐ha (2‐acre) plot. Four passes were made with the coulterometer. Seventy …

Estimating Percent Residue Cover Using The Line-Transect Method, David P. Shelton, Paul J. Jasa

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Leaving crop residue on the soil surface is one of the easiest and most cost-effective methods of reducing soil erosion. Research in Nebraska and other midwestern states has shown that leaving as little as 20 percent of the soil surface covered with crop residue can reduce soil erosion by one-half of what it would be from residue-free conditions. Greater amounts of residue cover will further reduce erosion. Many Conservation Plans specify crop residue management or residue left on the soil surface as the primary erosion control method. Generally, the amount of cover required after planting ranges from 30 percent to …

Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water availability for irrigation throughout the world has been reduced in recent years due to a combination of frequent droughts and competition for water resources among agricultural, industrial, and urban users. In addition, some major agricultural areas face moderate to significant reductions of rainfall, or changes in timing of stream flow due to changes in timing of snowmelt, as a result of global climate change. Under such conditions, sophisticated irrigation water management will be required to optimize water use efficiency and maintain sufficient levels of crop productivity and quality. A key factor to achieve these targets is the estimation of …

Regional Co2 And Latent Heat Surface Fluxes In The Southern Great Plains: Measurements, Modeling, And Scaling, W. J. Riley, Sebastien C. Biraud, Margaret S. Torn, Marc L. Fischer, David P. Billesbach, Joe A. Berry

Department of Agricultural and Biological Systems Engineering: Faculty Publications

[1] Characterizing net ecosystem exchanges (NEE) of CO2 and sensible and latent heat fluxes in heterogeneous landscapes is difficult, yet critical given expected changes in climate and land use. We report here a measurement and modeling study designed to improve our understanding of surface to atmosphere gas exchanges under very heterogeneous land cover in the mostly agricultural U.S. Southern Great Plains (SGP). We combined three years of site-level, eddy covariance measurements in several of the dominant land cover types with regional-scale climate data from the distributed Mesonet stations and Next Generation Weather Radar precipitation measurements to calibrate a land surface …

Facilitating Use Of The Odor Footprint Tool By Nebraska Pork Producers, Rick R. Stowell

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The goal of this project was to make Odor Footprint Tool (OFT) resources readily usable by pork producers and their technical advisors as a planning and screening tool when siting swine facilities. Detailed odor footprints for five specified sizes of swine facilities were developed for twenty-four locations throughout Nebraska: six regional sites and three “localized” sites within each region. Each odor footprint shows the predicted odor annoyance-free frequency as a function of the distance from the facility. Footprints developed using localized weather data differed only slightly from footprints produced using weather data from a regional site when the general topography …