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Central Mechanisms Regulating Pituitary-Adrenal Activity In Infant Guinea Pigs (Cavia Porcellus) During Exposure To Psychological Stressors: Independent And Combined Effects Of Maternal Separation And Novelty, Deborah Suzanne Maken Jan 2009

Central Mechanisms Regulating Pituitary-Adrenal Activity In Infant Guinea Pigs (Cavia Porcellus) During Exposure To Psychological Stressors: Independent And Combined Effects Of Maternal Separation And Novelty, Deborah Suzanne Maken

Browse all Theses and Dissertations

Separation from the maternal attachment figure, particularly when it occurs in a novel or threatening environment, reliably increases pituitary-adrenal activity in a number of species, and is thought to increase later susceptibility to psychopathology in humans. However, little is known about the central mechanisms mediating these effects. Therefore, I investigated cortisol and ACTH levels in plasma, corticotropin-releasing factor (CRF) mRNA expression in the hypothalamic paraventricular nucleus (PVN), and c-Fos activity in a circuit [medial amygdala (MeA)- bed nucleus of the stria terminalus (BNST)] thought to drive pituitary-adrenal activity during exposure to psychological stressors, as well as in the PVN. Measurements …


Genetic Differentiation In Ambystomatid Salamanders Across A Fragmented Landscape, Joseph E. Bartoszek Jan 2009

Genetic Differentiation In Ambystomatid Salamanders Across A Fragmented Landscape, Joseph E. Bartoszek

Browse all Theses and Dissertations

It is generally recognized that amphibian populations declining across the globe. Habitat loss is the primary cause of decline. The salamander family Ambystomatidae has experienced significantly more rapid decline than the average for amphibians. Coefficients of Conservatism (CoC) have been developed for amphibians in Ohio. These are based primarily on habitat requirements with high CoCs for amphibians with stringent habitat requirements (e.g. vernal pools associated with large, intact, undisturbed forest), and low CoCs for amphibians with less stringent habitat requirements. Genetic diversity in five species and one hybrid complex of ambystomatid salamander in southwest Ohio were examined and compared to …


Interfacial Modification Of Microcellular Carbon: Influence Of Ceramic And Carbon Nanotube Coatings, Anil Kumar Karumuri Jan 2009

Interfacial Modification Of Microcellular Carbon: Influence Of Ceramic And Carbon Nanotube Coatings, Anil Kumar Karumuri

Browse all Theses and Dissertations

Microcellular carbon is an emerging ultra lightweight and efficient thermal management material, which also has great potential as a reinforcement material for selected composites. However, these porous materials exhibit relatively low mechanical properties, and are susceptible to degradation in oxidizing environment. The scope of this research is to investigate surface modification approaches that can address these issues. Two specific objectives were: (1) to develop ceramic coatings to improve the survivability of carbon foams in high temperature applications, and (2) to develop and test modifications that can improve cellular composites involving carbon foam. It was seen that a mixed layer of …


Estimating The System Costs Of Wind Power Forecast Uncertainty, Judith Cardell, C. Lindsay Anderson, Chin Yen Tee Jan 2009

Estimating The System Costs Of Wind Power Forecast Uncertainty, Judith Cardell, C. Lindsay Anderson, Chin Yen Tee

Engineering: Faculty Publications

Uncertainty in forecasts of wind power generation raises concerns of integrating wind power into power system operations and electricity markets at acceptable costs. The analysis presented in this paper uses an optimal power flow (OPF) model in a Monte Carlo Simulation (MCS) framework to estimate the additional cost of power system operation with uncertain output from a wind farm. A base case dispatch is established along with alternate dispatches based upon a probability distribution of real time wind power generation. The cost of the uncertainty in wind power forecasts is then quantified in terms of the difference in production cost …


Fabrication Of Nanostructures For Improved Performance Of Electrochemical Sensors And For Reference Compensation In Localized Surface Plasmon Resonance Sensors, Prashanthi Para Jan 2009

Fabrication Of Nanostructures For Improved Performance Of Electrochemical Sensors And For Reference Compensation In Localized Surface Plasmon Resonance Sensors, Prashanthi Para

University of Kentucky Master's Theses

L‐glutamate is associated with several neurological disorders; thus, monitoring fast dynamics of L‐glutamate is of great importance in the field of neuroscience. Electrode miniaturization demanded by many applications leads to reduced surface area and decreased amounts of immobilized enzymes on coated electrodes. As a result, lower signal‐to‐noise ratios are observed for oxidase‐enzyme based sensors. To increase the signal‐to‐noise ratio we have developed a process to fabricate micro‐ and nano‐ structures on the microelectrode surface.

Localized surface‐plasmon resonances (SPR) has been extensively used to design label‐free biosensors that can monitor receptor‐ligand interactions. A major challenge with localized SPR sensors is that …


Sequencing, Analysis, And Annotation Of Expressed Sequence Tags For Camelus Dromedarius, Abdulaziz M. Al-Swailem, Maher M. Shehata, Faisel M. Abu-Duhier, Essam J. Al-Yamani, Khalid A. Al-Busadah, Mohammed S. Al-Arawi, Ali Y. Al-Khider, Abdullah N. Al-Muhaimeed, Fahad H. Al-Qahtani, Manee M. Manee, Badr M. Al-Shomrani, Saad M. Al-Qhtani, Amer S. Al-Harthi, Kadir C. Akdemir, Mehmet S. Inan, Hasan H. Otu Jan 2009

Sequencing, Analysis, And Annotation Of Expressed Sequence Tags For Camelus Dromedarius, Abdulaziz M. Al-Swailem, Maher M. Shehata, Faisel M. Abu-Duhier, Essam J. Al-Yamani, Khalid A. Al-Busadah, Mohammed S. Al-Arawi, Ali Y. Al-Khider, Abdullah N. Al-Muhaimeed, Fahad H. Al-Qahtani, Manee M. Manee, Badr M. Al-Shomrani, Saad M. Al-Qhtani, Amer S. Al-Harthi, Kadir C. Akdemir, Mehmet S. Inan, Hasan H. Otu

Department of Electrical and Computer Engineering: Faculty Publications

Despite its economical, cultural, and biological importance, there has not been a large scale sequencing project to date for Camelus dromedarius. With the goal of sequencing complete DNA of the organism, we first established and sequenced camel EST libraries, generating 70,272 reads. Following trimming, chimera check, repeat masking, cluster and assembly, we obtained 23,602 putative gene sequences, out of which over 4,500 potentially novel or fast evolving gene sequences do not carry any homology to other available genomes. Functional annotation of sequences with similarities in nucleotide and protein databases has been obtained using Gene Ontology classification. Comparison to available …


Genes Differentially Expressed By Cumulus Cells And Assays Using Same To Identify Pregnancy Competent Oocytes, Jose B. Cibelli, Amy E. Iager, Hasan H. Otu Jan 2009

Genes Differentially Expressed By Cumulus Cells And Assays Using Same To Identify Pregnancy Competent Oocytes, Jose B. Cibelli, Amy E. Iager, Hasan H. Otu

Department of Electrical and Computer Engineering: Faculty Publications

A genetic means of identifying "pregnancy competent" oocytes is provided. The means comprises detecting the level of expression of one or more genes that are expressed at characteristic levels (upregulated or downregulated) in cumulus cells derived from pregnancy competent oocytes. This characteristic gene expression level, or pattern referred to herein as the "pregnancy signature", also can be used to identify subjects with underlying conditions that impair or prevent the development of a viable pregnancy, e.g., pre-menopausal condition, other hormonal dysfunction, ovarian dysfunction, ovarian cyst, cancer or other cell proliferation disorder, autoimmune disease and the like. In preferred embodiments the …


Missouri River Recovery Program: Missouri River Basin Jan 2009

Missouri River Recovery Program: Missouri River Basin

United States Army Corps of Engineers, Omaha District

The Missouri River, the nation’s longest, travels more than 2,300 miles from Three Forks, Montana, to join the Mississippi River near St. Louis, Missouri. For centuries, the river has served as the center of life for the inhabitants of North America’s Great Plains. Following exploration and mapping by Lewis and Clark’s Corps of Discovery in the early 1800s, the Missouri River became the gateway to the West.

Historically, the dynamic and untamed Missouri River has produced violent floods in the spring and summer with erosive forces that ate away its banks and turned its waters the color of mud.

Since …


Missouri River Recovery Program: Emergent Sandbar Habitat Jan 2009

Missouri River Recovery Program: Emergent Sandbar Habitat

United States Army Corps of Engineers, Omaha District

This Value Engineering (VE) Report summarizes the events of the April 6-8, 2009 VE workshop facilitated by GeoVal, Inc. for the U.S. Army Corps of Engineers (USACE) Omaha District, Nebraska. The Missouri River Recovery Program - Emergent Sandbar Habitat Value Engineering Study focuses on the assessment of the Missouri River Recovery Program (MRRP) Habitat Creation Project with specific focus on the creation of emergent sandbar habitats, examining current plans and programs to seek out alternative approaches and ideas that will improve the overall performance of the program.

The MRRP seeks to mitigate near-term losses of Missouri River habitats and recover …


Missouri River Recovery Program: Putting The Pieces Together: Mrrp Main Programs Jan 2009

Missouri River Recovery Program: Putting The Pieces Together: Mrrp Main Programs

United States Army Corps of Engineers, Omaha District

The Missouri River Recovery Program (MRRP) is a comprehensive effort led by the U.S. Army Corps of Engineers in partnership with the U.S. Fish and Wildlife Service, Tribes, states, other federal agencies and non-governmental organizations to develop and implement actions to create a healthy Missouri River.

The MRRP consists of:

-The Missouri River Bank Stabilization and Navigation Project (BSNP) Fish
and Wildlife Mitigation Project

- The Amended Biological Opinion and the Corps’ Record of Decision related
to the Master Water Control Manual for the Missouri River

- The 2007 Water Resources Development Act

Each of these guiding authorities set out …


Farm Tractor Rollover Protection: Why Simply Getting Rollover Protective Structures Installed On All Tractors Is Not Sufficient, Roger M. Hoy Jan 2009

Farm Tractor Rollover Protection: Why Simply Getting Rollover Protective Structures Installed On All Tractors Is Not Sufficient, Roger M. Hoy

Department of Agricultural and Biological Systems Engineering: Faculty Publications

In North America, agricultural is one of the most hazardous occupations, trailing only mining and construction in likelihood of experiencing a serious injury or fatality. Without quoting specific statistics, roughly one-half of the serious injuries experienced each year involve an agricultural tractor, and roughly one-half of the serious injuries involving tractors are rollovers. It is well established that when a tractor is equipped with a rollover protective structure (ROPS) and seatbelt, and both are utilized, serious injuries rarely, if ever occur, in the event of an overturn. In fact, tractor overturns are the leading cause of agricultural fatalities in the …


Switchgrass For Bioethanol And Other Value-Added Applications: A Review, Deepak R. Keshwani, Jay J. Cheng Jan 2009

Switchgrass For Bioethanol And Other Value-Added Applications: A Review, Deepak R. Keshwani, Jay J. Cheng

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Switchgrass is a promising feedstock for value-added applications due to its high productivity, potentially low requirements for agricultural inputs and positive environmental impacts. The objective of this paper is to review published research on the conversion of switchgrass into bioethanol and other value-added products. Environmental benefits associated with switchgrass include the potential for carbon sequestration, nutrient recovery from runoff, soil remediation and provision of habitats for grassland birds. Pretreatment of switchgrass is required to improve the yields of fermentable sugars. Based on the type of pretreatment, glucose yields range from 70% to 90%, and xylose yields range from 70% to …


Plant Sterol And Policosanol Characterization Of Hexane Extracts From Grain Sorghum, Corn, And Their Ddgs, Caolina Leguizamón, Curtis L. Weller, Vicki L. Schlegel, Timothy P. Carr Jan 2009

Plant Sterol And Policosanol Characterization Of Hexane Extracts From Grain Sorghum, Corn, And Their Ddgs, Caolina Leguizamón, Curtis L. Weller, Vicki L. Schlegel, Timothy P. Carr

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Plant sterols (PS) and policosanols (PC) have been attributed with plasma cholesterol-lowering properties in humans. Hexane extracts from grain sorghum, corn and their distillers dried grain with solubles (DDGS), an important co-product of ethanol production, contain these health promoting compounds, which could be used to develop health promoting dietary products. However, limited information is currently available regarding optimal methods of extraction and their influence on plant sterol or PC levels and compositions. Therefore, the objective of this study was to quantify lipids, particularly PS and PC extracted from grain sorghum and its DDGS using reflux and Soxtec methods. Corn and …


Thermal Degradation Kinetics Of Distillers Grains And Solubles In Nitrogen And Air, Lijun Wang, Ajay Kumar, Milford Hanna, Curtis L. Weller, D. D. Jones Jan 2009

Thermal Degradation Kinetics Of Distillers Grains And Solubles In Nitrogen And Air, Lijun Wang, Ajay Kumar, Milford Hanna, Curtis L. Weller, D. D. Jones

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The pyrolysis and oxidation kinetics of distillers grains and solubles were determined using thermogravimetric analysis. The starting temperature of pyrolysis and oxidation of distillers grains and solubles increased with the increase of heating rate and initial moisture content. The pyrolysis and oxidation of distillers grains and solubles were completed at 650°C and 850°C, respectively, which were independent of the heating rate and the initial moisture content. The residual weights of distillers grains and solubles after pyrolysis and oxidation were 27.15% and 5.49% of the original dry mass of distillers grains and solubles. Thermogravimetrical analysis data was used to determine kinetic …


Indirect Land Use Emissions In The Life Cycle Of Biofuels: Regulations Vs. Science, Adam J. Liska, Richard K. Perrin Jan 2009

Indirect Land Use Emissions In The Life Cycle Of Biofuels: Regulations Vs. Science, Adam J. Liska, Richard K. Perrin

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Recent legislative mandates have been enacted at state and federal levels with the purpose of reducing life cycle greenhouse gas (GHG) emissions from transportation fuels. This legislation encourages the substitution of fossil fuels with “low-carbon” fuels. The burden is put on regulatory agencies to determine the GHG-intensity of various fuels, and those agencies naturally look to science for guidance. Even though much progress has been made in determining the direct life cycle emissions from the production of biofuels, the science underpinning the estimation of potentially significant emissions from indirect land use change (ILUC) is in its infancy. As legislation requires …


Sorghum Distillers Dried Grain Lipid Extract Increases Cholesterol Excretion And Decreases Plasma And Liver Cholesterol Concentration In Hamsters, Jia Tse Hoi, Curtis L. Weller, Vicki Schlegel, Susan L. Cuppett, Ji-Young Lee, Timothy P. Carr Jan 2009

Sorghum Distillers Dried Grain Lipid Extract Increases Cholesterol Excretion And Decreases Plasma And Liver Cholesterol Concentration In Hamsters, Jia Tse Hoi, Curtis L. Weller, Vicki Schlegel, Susan L. Cuppett, Ji-Young Lee, Timothy P. Carr

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Grain sorghum is a rich source of phytochemicals. In this study, male hamsters were fed AIN-93M diets supplemented with a hexane-extractable lipid fraction from sorghum distillers dried grains with solubles (DDGS). Diets contained 0.0%, 0.5%, 1.0%, and 5.0% (w/w) DDGS lipid extract. After 4 wk, the 5.0% DDGS lipids group had significantly lower plasma non-HDL cholesterol and liver esterified cholesterol concentration. Fecal neutral sterol (i.e., cholesterol) excretion was significantly higher in the 5.0% DDGS lipids group compared to the other treatments (66% higher compared to controls). Bile acid excretion was not affected by DDGS lipid intake. Fecal cholesterol excretion was …


Antiproliferation Properties Of Grain Sorghum Dry Distiller’S Grain Lipids In Caco-2 Cells, Richard Zbasnik, Timothy P. Carr, Curtis L. Weller, Keum Taek Hwang, Lijun Wang, Susan L. Cuppett, Vicki Schlegel Jan 2009

Antiproliferation Properties Of Grain Sorghum Dry Distiller’S Grain Lipids In Caco-2 Cells, Richard Zbasnik, Timothy P. Carr, Curtis L. Weller, Keum Taek Hwang, Lijun Wang, Susan L. Cuppett, Vicki Schlegel

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Antiproliferative properties of lipids extracted from grain sorghum (GS) dry distiller’s grain (DDG) were analyzed to determine the feasibility of developing GS coproducts as a source for human health dietary ingredients. The lipid extract of GSDDG was delivered to human colon carcinoma (Caco-2) cells by solubilizing 0−1000 μg/mL of GS-DDG lipids in 100 μg/mL increments with micelles. A significant reduction in cell viability (25−50%) resulted at treatment levels of 400−1000 μg/mL GS-DDG lipids (p < 0.05). Alternatively, total protein levels of cells treated with 400, 500, and 600 μg/mL of GS-DDG lipid were not significantly different from the control, indicating cell growth during the treatment period. Total cell counts for the control were not significantly different from the GS-DDG lipid treated cells, but dead cell counts increased by 10% for the latter sample with a concomitant increase of the intercellular protein lactate dehydrogenase leakage (30−40%) in the medium. Preliminary analysis by the fluorescence-activated cell method (FACs) demonstrated that nonviable cells were in either the early apoptotic, late apoptotic, or necrotic stage post-treatment with 400, 500, and 600 μg/mL GS-DDG lipids. Physiochemical characterization of the GS-DDG lipids used for the antiproliferation study showed the presence of vitamin E (predominantly γ-tocopherol), triacylglycerides (predominantly linoleic acid), policosanols, aldehydes, and sterols (predominantly campesterol and stigmasterol), each of which or as synergistic/additive group of constituents may be responsible for the antiproliferative effect.


Grand Challenges For Biological Engineering, Jeong-Yeol Yoon, Mark R. Riley Jan 2009

Grand Challenges For Biological Engineering, Jeong-Yeol Yoon, Mark R. Riley

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Biological engineering will play a significant role in solving many of the world's problems in medicine, agriculture, and the environment. Recently the U.S. National Academy of Engineering (NAE) released a document "Grand Challenges in Engineering," covering broad realms of human concern from sustainability, health, vulnerability and the joy of living. Biological engineers, having tools and techniques at the interface between living and non-living entities, will play a prominent role in forging a better future. The 2010 Institute of Biological Engineering (IBE) conference in Cambridge, MA, USA will address, in part, the roles of biological engineering in solving the challenges presented …


Impact Of Microclimatic Data Measured Above Maize And Grass Canopies On Penman‐Monteith Reference Evapotranspiration Calculations, Suat Irmak, Lameck O. Odhiambo Jan 2009

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 (ETref) using measured microclimatic data and the Penman‐Monteith (PM) method provides a powerful means of quantifying actual plant evapotranspiration (ETa) needed for use in various disciplines. When applying the PM method to estimate ETref, 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 Jan 2009

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 …


Integration Of An Extended Octagonal Ring Transducer And Soil Coulterometer For Identifying Soil Compaction, Santosh Pitla, L. G. Wells, S. A. Shearer Jan 2009

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 …


N-Glycosylation Microheterogeneity And Site Occupancy Of An Asn-X-Cys Sequon In Plasma-Derived And Recombinant Protein C, Geun-Cheol Gil, William H. Velander, Kevin E. Van Cott Jan 2009

N-Glycosylation Microheterogeneity And Site Occupancy Of An Asn-X-Cys Sequon In Plasma-Derived And Recombinant Protein C, Geun-Cheol Gil, William H. Velander, Kevin E. Van Cott

Kevin Van Cott Publications

Human protein C (hPC) is glycosylated at three Asn-X-Ser/Thr and one atypical Asn-X-Cys sequons. We have characterized the micro- and macro-heterogeneity of plasma-derived hPC and compared the glycosylation features with recombinant protein C (tg-PC) produced in a transgenic pig bioreactor from two animals having approximately tenfold different expression levels. The N-glycans of hPC are complex di- and tri-sialylated structures, and we measured 78% site occupancy at Asn-329 (the Asn-X-Cys sequon). The N-glycans of tg-PC are complex sialylated structures, but less branched and partially sialylated. The porcine mammary epithelial cells glycosylate the Asn-X-Cys sequon with a similar efficiency as human hepatocytes …


Bess: BIofuel ENergy SYstems SImulator: Life Cycle Energy & Emissions Analysis Model For Corn-Ethanol Biofuel Production Systems -- User’S Guide For The Bess Model, Adam Liska, Haishun Yang, Daniel T. Walters, Kenneth Cassman, Terry Klopfenstein, Galen Erickson, Virgil R. Bremer, Richard K. Koelsch, Dan Kenney, Patrick Tracy Jan 2009

Bess: BIofuel ENergy SYstems SImulator: Life Cycle Energy & Emissions Analysis Model For Corn-Ethanol Biofuel Production Systems -- User’S Guide For The Bess Model, Adam Liska, Haishun Yang, Daniel T. Walters, Kenneth Cassman, Terry Klopfenstein, Galen Erickson, Virgil R. Bremer, Richard K. Koelsch, Dan Kenney, Patrick Tracy

Adam Liska Papers

The BESS model is a software tool to calculate the energy efficiency, greenhouse gas (GHG) emissions, and natural resource requirements of corn–to-ethanol biofuel production systems. The model provides a “cradle-to-grave” analysis of the production life cycle of biofuels from the creation of material inputs to finished products, producing an inventory of distributed GHG emissions from fossil fuels and a few key indirect emissions in the production life cycle. The model parameters can be set by the user to achieve the highest accuracy in evaluating a single corn-ethanol biorefinery and its surrounding feedstock crop production zone. The model equations and summary …


An Idealized Model And Systematic Process Study Of Oxygen Depletion In Highly Turbid Estuaries, Stefan A. Talke, Huib E. De Swart, Victor De Jonge Jan 2009

An Idealized Model And Systematic Process Study Of Oxygen Depletion In Highly Turbid Estuaries, Stefan A. Talke, Huib E. De Swart, Victor De Jonge

Civil and Environmental Engineering Faculty Publications and Presentations

The sensitivity of oxygen depletion in turbid estuaries to parameters like freshwater discharge, depth, and sediment availability is investigated using an idealized model. The model describes tidally averaged circulation and suspended sediment concentration (SSC), which are input into an advection–diffusion sink module of dissolved oxygen (DO). Based on the analysis of field data collected in the Ems estuary, the modeled oxygen depletion rates are proportional to SSC. The model is calibrated to the observed variation of DO with SSC and temperature. Modeled DO closely tracks changes to the estuarine turbidity zone (ETZ): increased channel depth, decreased freshwater discharge, and decreased …


Mathematical Modeling Of Growth Of Salmonella In Raw Ground Beef Under Isothermal Conditions From 10 To 45° C, Vijay K. Juneja, Martin Valenzuela Melendres, Lihan Huang, Jeyamkondan Subbiah, Harshavardhan Thippareddi Jan 2009

Mathematical Modeling Of Growth Of Salmonella In Raw Ground Beef Under Isothermal Conditions From 10 To 45° C, Vijay K. Juneja, Martin Valenzuela Melendres, Lihan Huang, Jeyamkondan Subbiah, Harshavardhan Thippareddi

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The objective of this study was to develop primary and secondary models to describe the growth of Salmonella in raw ground beef. Primary and secondary models can be integrated into a dynamic model that can predict the microbial growth under varying environmental conditions. Growth data of Salmonella at nine different isothermal conditions — 10,15, 20, 25, 28, 32, 35, 42, and 45 °C were first fitted into primary models, namely the logistic, modified Gompertz, Baranyi, and Huang models. Performances of these models were evaluated by using various statistical criteria, namely mean square error (MSE), pseudo-R2, −2 log likelihood, …


Effect Of Timing Of A Deficit-Irrigation Allocation On Corn Evapotranspiration, Yield, Water Use Efficiency And Dry Mass, J. O. Payero, David D. Tarkalson, Suat Irmak, Don Davison, James L. Petersen Jan 2009

Effect Of Timing Of A Deficit-Irrigation Allocation On Corn Evapotranspiration, Yield, Water Use Efficiency And Dry Mass, J. O. Payero, David D. Tarkalson, Suat Irmak, Don Davison, James L. Petersen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Water regulations have decreased irrigation water supplies in Nebraska and some other areas of the USA Great Plains. When available water is not enough to meet crop water requirements during the entire growing cycle, it becomes critical to know the proper irrigation timing that would maximize yields and profits. This study evaluated the effect of timing of a deficit-irrigation allocation (150 mm) on crop evapotranspiration (ETc), yield, water use efficiency (WUE = yield/ETc), irrigation water use efficiency (IWUE = yield/irrigation), and dry mass (DM) of corn (Zea mays L.) irrigated with subsurface drip irrigation in the semiarid climate of …


Special Issue On Evapotranspiration Measurement And Modeling, Samuel Ortega-Farias, Suat Irmak, R. H. Cuenca Jan 2009

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 Jan 2009

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 …


Multi-Component Nanofibrous Scaffolds With Tunable Properties For Bone Tissue Engineering, Moncy V. Jose Jan 2009

Multi-Component Nanofibrous Scaffolds With Tunable Properties For Bone Tissue Engineering, Moncy V. Jose

All ETDs from UAB

Bone is a highly complex tissue which is an integral part of vertebrates and hence any damage has a major negative effect on the quality of life. Tissue engineering is regarded as an ideal route to resolve the issues related to the scarcity of tissue and organ for transplantation. Apart from cell line and growth factors, the choice of materials and fabrication technique for scaffold are equally important. The goal of this work was to develop a multi-component nanofibrous scaffold based on a synthetic polymer (poly(lactic-co-glycolide) (PLGA)), a biopolymer (collagen) and a biomineral (nano-hydroxyapatite (na-no-HA)) by electrospinning technique, which mimics …


Optical Nonlinear Interactions In Dielectric Nano-Suspensions, Ramy El-Ganainy Jan 2009

Optical Nonlinear Interactions In Dielectric Nano-Suspensions, Ramy El-Ganainy

Electronic Theses and Dissertations

This work is divided into two main parts. In the first part (chapters 2-7) we consider the nonlinear response of nano-particle colloidal systems. Starting from the Nernst-Planck and Smoluchowski equations, we demonstrate that in these arrangements the underlying nonlinearities as well as the nonlinear Rayleigh losses depend exponentially on optical intensity. Two different nonlinear regimes are identified depending on the refractive index contrast of the nanoparticles involved and the interesting prospect of self-induced transparency is demonstrated. Soliton stability is systematically analyzed for both 1D and 2D configurations and their propagation dynamics in the presence of Rayleigh losses is examined. We …