Digital Commons Network^™

Mulch And Groundcover Effects On Soil Temperature And Moisture, Surface Reflectance, Grapevine Water Potential, And Vineyard Weed Management, Christina M. Bavougian, Paul E. Read

Department of Agronomy and Horticulture: Faculty Publications

The objectives of this research were to identify alternatives to glyphosate for intra- row (under-trellis) vineyard floor management and to evaluate the potential for intra- row and inter-row (alleyway) groundcovers to reduce vegetative vigor of `Marquette' grapevines (Vitis spp.) in a southeast Nebraska vineyard. The experiment was a randomized factorial design with five intra-row treatments (crushed glass mulch [CG], distillers' grain mulch [DG], creeping red fescue [CRF], non-sprayed control [NSC], and glyphosate [GLY]) and three inter-row treatments (creeping red fescue [CRF], Kentucky bluegrass [KB], and resident vegetation [RV]). Treatments were established in 2010-2011 and measurements were conducted during 2012 …

Empirical Comparisons Of Different Statistical Models To Identify And Validate Kernel Row Number-Associated Variants From Structured Multi-Parent Mapping Populations Of Maize, Jinliang Yang, Cheng-Ting Yeh, Raghuprakash Kastoori Ramamurthy, Xinshuai Qi, Rohan L. Fernando, Jack C. M. Dekkers, Dorian J. Garrick, Dan Nettleton, Patrick Schnable

Department of Agronomy and Horticulture: Faculty Publications

Advances in next generation sequencing technologies and statistical approaches enable genomewide dissection of phenotypic traits via genome-wide association studies (GWAS). Although multiple statistical approaches for conducting GWAS are available, the power and cross-validation rates of many approaches have been mostly tested using simulated data. Empirical comparisons of single variant (SV) and multi-variant (MV) GWAS approaches have not been conducted to test if a single approach or a combination of SV and MV is effective, through identification and cross-validation of trait-associated loci. In this study, kernel row number (KRN) data were collected from a set of 6,230 entries derived from the …

Quantifying Variance Across Spatial Scales As Part Of Fire Regime Classifications, Rheinhardt Scholtz, Samuel D. Fuhlendorf, Sherry A. Leis, Joshua J. Picotte, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

The emergence of large-scale fire classifications and products informed by remote sensing data has enabled opportunities to include variability or heterogeneity as part of modern fire regime classifications. Currently, basic fire metrics such as mean fire return intervals are calculated without considering spatial variance in a management context. Fire return intervals are also only applicable at a particular grain size (defined as the spatial unit of interest) even though they are typically applied homogeneously. In this study, we utilized a 29-yr fire occurrence database to show how spatial variance changes with respect to grain as postulated by Wiens (1989) when …

Phosphate Deficiency Negatively Affects Early Steps Of The Symbiosis Between Common Bean And Rhizobia, Mariel C. Isidra-Arellano, Maria Del Rocio Reyero-Saavedra, Maria Del Socorro Sanchez-Correa, Lise Pingault, Sidharth Sen, Trupti Joshi, Lourdes Girard, Norma A. Castro-Guerrero, David G. Mendoza-Cozatl, Marc Libault, Oswaldo Valdes-Lopez

Department of Agronomy and Horticulture: Faculty Publications

Phosphate (Pi) deficiency reduces nodule formation and development in different legume species including common bean. Despite significant progress in the understanding of the genetic responses underlying the adaptation of nodules to Pi deficiency, it is still unclear whether this nutritional deficiency interferes with the molecular dialogue between legumes and rhizobia. If so, what part of the molecular dialogue is impaired? In this study, we provide evidence demonstrating that Pi deficiency negatively affects critical early molecular and physiological responses that are required for a successful symbiosis between common bean and rhizobia. We demonstrated that the infection thread formation and the expression …

Genetic Architecture Of Common Bunt Resistance In Winter Wheat Using Genome-Wide Association Study, Amira M. I. Mourad, Ahmed Sallam, Vikas Belamkar, Ezzat Mahdy, Bahy Bakheit, Atif Abo El-Wafaa, P. Stephen Baenziger

Department of Agronomy and Horticulture: Faculty Publications

Background: Common bunt (caused by Tilletia caries and T. foetida) has been considered as a major disease in wheat (Triticum aestivum) following rust (Puccinia spp.) in the Near East and is economically important in the Great Plains, USA. Despite the fact that it can be easily controlled using seed treatment with fungicides, fungicides often cannot or may not be used in organic and low-input fields. Planting common bunt resistant genotypes is an alternative.

Results: To identify resistance genes for Nebraska common bunt race, the global set of differential lines were inoculated. Nine differential lines carrying nine …

Improving Fertilizer Recommendations For Nepalese Farmers With The Help Of Soil-Testing Mobile Van, Sunil Pandey, Netra Prasad Bhatta, Prakash Paudel, Rajan Pariyar, Kiran Hari Maskey, Janardan Khadka, Tuk Bahadur Thapa, Balaram Rijal, Dinesh Panday

Department of Agronomy and Horticulture: Faculty Publications

Smallholder farmers dominate agriculture in Nepal. These farmers have poor knowledge about agriculture and lack of support for soil management and integrated plant-nutrient systems. Focusing on the importance and need for soil-fertility management, a soil-testing mobile van program has recently been introduced in Nepal by Soil Management Directorate, Hariharbhawan. With the introduction of the mobile lab, famers can get their soil tested for nutrient deficiencies and fertilizer requirements at their doorsteps. Using mobile lab, spatial distributions of chemical properties, including pH, organic matter (OM), total nitrogen (N), available phosphorus (as P₂O₅), and available potassium (as K …

Influence Of Harvest Date On Seed Yield And Quality In Forage Kochia, Cody F. Creech, Blair L. Waldron, Corey V. Ransom, Dale R. Zobell, Joseph Earl Creech

Department of Agronomy and Horticulture: Faculty Publications

Forage kochia (Bassia prostrata) is used for rangeland reclamation and livestock and wildlife forage, but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies virescens and grisea. Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most accessions. Cultivar Snowstorm and breeding line Sahsel, both subsp. grisea, had the greatest 100-seed weights in November, 155 …

Identification Of Quantitative Trait Loci Conferring Resistance To Tan Spot In A Biparental Population Derived From Two Nebraska Hard Red Winter Wheat Cultivars, Gayan K. Kariyawasam, Waseem Hussain, Amanda Easterly, Mary Guttieri, Vikas Belamkar, Jesse Poland, Jorge Venegas, Stephen Baenziger, Francois Marais, Jack B. Rasmussen, Zhaohui Liu

Department of Agronomy and Horticulture: Faculty Publications

Tan spot, caused by Pyrenophora triticirepentis (Ptr), is a destructive foliar disease in all types of cultivated wheat worldwide. Genetics of tan spot resistance in wheat is complex, involving insensitivity to fungal-produced necrotrophic effectors (NEs), major resistance genes, and quantitative trait loci (QTL) conferring race-nonspecific and race-specific resistance. The Nebraska hard red winter wheat (HRWW) cultivar ‘Wesley’ is insensitive to Ptr ToxA and highly resistant to multiple Ptr races, but the genetics of resistance in this cultivar is unknown. In this study, we used a recombinant inbred line (RIL) population derived from a cross between Wesley and another …

Lignocellulosic-Based Bioenergy And Water Quality Parameters: A Review, Bharat Sharma Acharya, Humberto Blanco-Canqui

Department of Agronomy and Horticulture: Faculty Publications

High rates of crop residue removal as biofuel feedstocks could increase losses of nonpoint source pollutants, negatively affecting water quality. An alternative to residue removal can be growing dedicated bioenergy crops such as warm season grasses (WSGs) and short-rotation woody crops (SRWCs). Yet, our understanding of the implications of growing dedicated bioenergy crops on water quality is limited. Thus, we (i) synthesized and compared the impacts of crop residue removal, WSGs, and SRWCs on water quality parameters (i.e., sediment and nutrient runoff, and nutrient leaching) and (ii) identified research gaps for growing dedicated energy crops. Literature indicates that residue removal …

Epigenomic Plasticity Of Arabidopsis Msh1 Mutants Under Prolonged Cold Stress, Sunil Kumar Kenchanmane Raju, Mon-Ray Shao, Yashitola Wamboldt, Sally A. Mackenzie

Department of Agronomy and Horticulture: Faculty Publications

Dynamic transcriptional and epigenetic changes enable rapid adaptive benefit to environmental fluctuations. However, the underlying mechanisms and the extent to which this occurs are not well known. MutS Homolog 1 (MSH1) mutants cause heritable developmental phenotypes accompanied by modulation of defense, phytohormone, stress‐response, and circadian rhythm genes, as well as heritable changes in DNA methylation patterns. Consistent with gene expression changes, msh1 mutants display enhanced tolerance for abiotic stress including drought and salt stress, while showing increased susceptibility to freezing temperatures. Despite changes in defense and biotic stress‐response genes, msh1 mutants showed increasing susceptibility to the bacterial pathogen Pseudomonas syringae. …

The Open Source Gaitor Suite For Rodent Gait Analysis, Brittany Y. Jacobs, Emily H. Lakes, Alex J. Reiter, Spencer P. Lake, Trevor R. Ham, Nic D. Leipzig, Stacy L. Porvasnik, Christine E. Schmidt, Rebecca A. Wachs, Kyle D. Allen

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Locomotive changes are often associated with disease or injury, and these changes can be quantified through gait analysis. Gait analysis has been applied to preclinical studies, providing quantitative behavioural assessment with a reasonable clinical analogue. However, available gait analysis technology for small animals is somewhat limited. Furthermore, technological and analytical challenges can limit the effectiveness of preclinical gait analysis. The Gait Analysis Instrumentation and Technology Optimized for Rodents (GAITOR) Suite is designed to increase the accessibility of preclinical gait analysis to researchers, facilitating hardware and software customization for broad applications. Here, the GAITOR Suite’s utility is demonstrated in 4 models: …

Greenhouse Gas Emissions From Beef Feedlot Surface Materials As Affected By Diet, Moisture, Temperature, And Time, Bryan L. Woodbury, John E. Gilley, David B. Parker, Bobbi S. Stomer

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A laboratory study was conducted to measure the effects of diet, moisture, temperature, and time on greenhouse gas (GHG) emissions from feedlot surface materials (FSM). The FSM were collected from open-lot pens where beef cattle were fed either a dry-rolled corn (DRC) diet containing no wet distillers grains with solubles (WDGS) or a DRC diet containing 35% WDGS. The FSM were collected, air-dried or mixed with 3.0 L of water to represent dry or wet conditions, and then incubated at temperatures of 5°C, 15°C, 25°C, or 35°C. Static flux chambers were used to quantify GHG emissions over a 14-day period. …

Total Mercury Determination In Muscle And Liver Tissue Samples From Brazilian Amazon Fish Using Slurry Sampling, João Vitor De Queiroz, José Cavalcante Souza Vieira, Izabela Da Cunha Bataglioli, Alis Correia Bittarello, Camila Pereira Braga, Grasieli De Oliveira, Cilene Do Carmo Federici Padilha, Pedro De Magalhães Padilha

Department of Biochemistry: Faculty Publications

This paper presents a slurry sampling method for total mercury determination by graphite furnace atomic absorption spectrometry (GFAAS) in tissue of fish from the Amazon. The tissue samples were lyophilized and macerated, and then the slurry samples were prepared by putting 20 mg of tissue, added to a solution containing Triton X-100, Suprapur HNO₃, and zirconium nitrate directly in sampling vials of a spectrometer. Mercury standard solutions were prepared under the same conditions as the slurry samples. The slurry samples and the mercury standard solutions were sonicated for 20 s. Twenty microliters of slurry samples were injected into …

Towards The Synthetic Design Of Camelina Oil Enriched In Tailored Acetyl-Triacylglycerols With Medium-Chain Fatty Acids, Sunil Bansal, Hae Jin Kim, Gunnam Na, Megan E. Hamilton, Edgar B. Cahoon, Chaofu Lu, Timothy P. Durrett

Department of Biochemistry: Faculty Publications

The ability to manipulate expression of key biosynthetic enzymes has allowed the development of genetically modified plants that synthesise unusual lipids that are useful for biofuel and industrial applications. By taking advantage of the unique activities of enzymes from different species, tailored lipids with a targeted structure can be conceived. In this study we demonstrate the successful implementation of such an approach by metabolically engineering the oilseed crop Camelina sativa to produce 3-acetyl-1,2-diacyl-sn-glycerols (acetyl-TAGs) with medium-chain fatty acids (MCFAs). Different transgenic camelina lines that had been genetically modified to produce MCFAs through the expression of MCFA-specific thioesterases and …

Endosomal Escape Of Antisense Oligonucleotides Internalized By Stabilin Receptors Is Regulated By Rab5c And Eea1 During Endosomal Maturation, Colton M. Miller, W. Brad Wan, Punit P. Seth, Edward N. Harris

Department of Biochemistry: Faculty Publications

Second-generation (Gen 2) Antisense oligonucleotides (ASOs) show increased nuclease stability and affinity for their RNA targets, which has translated to improved potency and therapeutic index in the clinic. Gen 2 ASOs are typically modified using the phosphorothioate (PS) backbone modification, which enhances ASO interactions with plasma, cell surface, and intracellular proteins. This facilitates ASO distribution to peripheral tissues and also promotes cellular uptake after injection into animals. Previous work identified that Stabilin receptors specifically internalize PS-ASOs in the sinusoidal endothelial cells of the liver and the spleen. By modulating expression of specific proteins involved in the trafficking and maturation of …

Purification Of Hepatocytes And Sinusoidal Endothelial Cells From Mouse Liver Perfusion, Fatima Cabral, Colton M. Miller, Katrina M. Kudrna, Blake E. Hass, Jocelyn G. Daubendiek, Brianna M. Kellar, Edward N. Harris

Department of Biochemistry: Faculty Publications

This protocol demonstrates a method for obtaining high yield and viability for mouse hepatocytes and sinusoidal endothelial cells (SECs) suitable for culturing or for obtaining cell lysates. In this protocol, the portal vein is used as the site for catheterization, rather than the vena cava, as this limits contamination of other possible cell types in the final liver preparation. No special instrumentation is required throughout the procedure. A water bath is used as a source of heat to maintain the temperature of all the buffers and solutions. A standard peristaltic pump is used to drive the fluid, and a refrigerated …

A Tlr/Akt/Foxo3 Immune Tolerance–Like Pathway Disrupts The Repair Capacity Of Oligodendrocyte Progenitors, Taasin Srivastava, Parham Diba, Justin M. Dean, Fatima Banine, Daniel Shaver, Matthew Hagen, Xi Gong, Weiping Su, Ben Emery, Daniel L. Marks, Edward N. Harris, Bruce Baggentoss, Paul H. Weigel, Larry S. Sherman, Stephen A. Back

Department of Biochemistry: Faculty Publications

Cerebral white matter injury (WMI) persistently disrupts myelin regeneration by oligodendrocyte progenitor cells (OPCs). We identified a specific bioactive hyaluronan fragment (bHAf) that downregulates myelin gene expression and chronically blocks OPC maturation and myelination via a tolerance-like mechanism that dysregulates pro-myelination signaling via AKT. Desensitization of AKT occurs via TLR4 but not TLR2 or CD44. OPC differentiation was selectively blocked by bHAf in a maturation-dependent fashion at the late OPC (preOL) stage by a noncanonical TLR4/TRIF pathway that induced persistent activation of the FoxO3 transcription factor downstream of AKT. Activated FoxO3 selectively localized to oligodendrocyte lineage cells in white matter …

3-O Sulfation Of Heparin Leads To Hepatotropism And Longer Circulatory Half-Life, Colton M. Miller, Yongmei Xu, Katrina M. Kudrna, Blake E. Hass, Brianna M. Kellar, Andrew W. Egger, Jian Liu, Edward N. Harris

Department of Biochemistry: Faculty Publications

Introduction: Heparins are common blood anticoagulants that are critical for many surgical and biomedical procedures used in modern medicine. In contrast to natural heparin derived from porcine gut mucosa, synthetic heparins are homogenous by mass, polymer length, and chemistry.

Materials & methods: Stable cell lines expressing the human and mouse Stabilin receptors were used to evaluate endocytosis of natural and synthetic heparin. We chemoenzymatically produced synthetic heparin consisting of 12 sugars (dodecamers) containing 14 sulfate groups resulting in a non-3-O sulfated structure (n12mer). Half of the n12mer was modified with a 3-O sulfate on a single GlcNS sugar producing the …

Role Of Selenof As A Gatekeeper Of Secreted Disulfide-Rich Glycoproteins, Sun Hee Yim, Robert A. Everley, Frank A. Schildberg, Sang-Goo Lee, Andrea Orsi, Zachary R. Barbati, Kutay Karatepe, Dmitry E. Fomenko, Petra A. Tsuji, Hongbo R. Luo, Steven P. Gygi, Roberto Sitia, Arlene H. Sharpe, Dolph L. Hatfield, Vadim N. Gladyshev

Department of Biochemistry: Faculty Publications

Selenof (15-kDa selenoprotein; Sep15) is an endoplasmic reticulum (ER)-resident thioredoxin-like oxidoreductase that occurs in a complex with UDPglucose: glycoprotein glucosyltransferase. We found that Selenof deficiency in mice leads to elevated levels of non-functional circulating plasma immunoglobulins and increased secretion of IgM during in vitro splenic B cell differentiation. However, Selenof knockout animals show neither enhanced bacterial killing capacity nor antigen-induced systemic IgM activity, suggesting that excess immunoglobulins are not functional. In addition, ER-to-Golgi transport of a target glycoprotein was delayed in Selenof knockout embryonic fibroblasts, and proteomic analyses revealed that Selenof deficiency is primarily associated with antigen presentation and ER-to-Golgi …

Long-Chain Omega-3 Polyunsaturated Fatty Acids Modulate Mammary Gland Composition And Inflammation, Saraswoti Khadge, Geoffrey M. Thiele, J. Graham Sharp, Timothy R. Mcguire, Lynell W. Klassen, Paul N. Black, Concetta Dirusso, James Talmadge

Department of Biochemistry: Faculty Publications

Studies in rodents have shown that dietary modifications as mammary glands (MG) develop, regulates susceptibility to mammary tumor initiation. However, the effects of dietary PUFA composition on MGs in adult life, remains poorly understood. This study investigated morphological alterations and inflammatory microenvironments in the MGs of adult mice fed isocaloric and isolipidic liquid diets with varying compositions of omega (ω)-6 and long-chain (Lc)-ω3FA that were pair-fed. Despite similar consumption levels of the diets, mice fed the ω-3 diet had significantly lower body-weight gains, and abdominal-fat and mammary fat pad (MFP) weights. Fatty acid analysis showed significantly higher levels of Lc-ω-3FAs …

Dietary Omega-3 And Omega-6 Polyunsaturated Fatty Acids Modulate Hepatic Pathology, Saraswoti Khadge, J. Graham Sharp, Geoffrey M. Thiele, Timothy R. Mcguire, Lynell W. Klassen, Michael J. Duryee, Holly C. Britton, Jordan Beck, Paul N. Black, Concetta Dirusso, James Talmadge

Department of Biochemistry: Faculty Publications

Recent evidence has suggested that dietary polyunsaturated fatty acids (PUFAs) modulate inflammation; however, few studies have focused on the pathobiology of PUFA using isocaloric and isolipidic diets and it is unclear if the associated pathologies are due to dietary PUFA composition, lipid metabolism or obesity, as most studies compare diets fed ad libitum. Our studies used isocaloric and isolipidic liquid diets (35% of calories from fat), with differing compositions of omega (ω)-6 or long chain (Lc) ω-3 PUFA that were pair-fed and assessed hepatic pathology, inflammation and lipid metabolism. Consistent with an isocaloric, pair-fed model we observed no significant difference …

Adenosine Has Two Faces: Regionally Dichotomous Adenosine Tone In A Model Of Epilepsy With Comorbid Sleep Disorders, Ted J. Warren, Timothy A. Simeone, D. David Smith, Ryan Grove, Jiri Adamec, Kaeli K. Samson, Harrison M. Roundtree, Deepak Madhavan, Kristina A. Simeone

Department of Biochemistry: Faculty Publications

Objective: Adenosine participates in maintaining the excitatory/inhibitory balance in neuronal circuits. Studies indicate that adenosine levels in the cortex and hippocampus increase and exert sleep pressure in sleep-deprived and control animals, whereas in epilepsy reduced adenosine tone promotes hyperexcitability. To date, the role of adenosine in pathological conditions that result in both seizures and sleep disorders is unknown. Here, we determined adenosine tone in sleep and seizure regulating brain regions of Kv1.1 knockout (KO) mice, a model of temporal epilepsy with comorbid sleep disorders.

Methods: 1) Reverse phase-high performance liquid chromatography (RP-HPLC) was performed on brain tissue to determine levels …

Influenza D Virus M2 Protein Exhibits Ion Channel Activity In Xenopus Laevis Oocytes, Evan Kesinger, Jianing Liu, Aaron Jensen, Catherine P. Chia, Andrew Demers, Hideaki Moriyama

School of Biological Sciences: Faculty Publications

A new type of influenza virus, known as type D, has recently been identified in cattle and pigs. Influenza D virus infection in cattle is typically asymptomatic; however, its infection in swine can result in clinical disease. Swine can also be infected with all other types of influenza viruses, namely A, B, and C. Consequently, swine can serve as a "mixing vessel" for highly pathogenic influenza viruses, including those with zoonotic potential. Currently, the only antiviral drug available targets influenza M2 protein ion channel is not completely effective. Thus, it is necessary to develop an M2 ion channel blocker capable …

Mitochondrial Dysfunction And Infection Generate Immunity–Fecundity Tradeoffs In Drosophila, Justin L. Buchanan, Colin D. Meiklejohn, Kristi L. Montooth

School of Biological Sciences: Faculty Publications

Physiological responses to short-term environmental stressors, such as infection, can have long-term consequences for fitness, particularly if the responses are inappropriate or nutrient resources are limited. Genetic variation affecting energy acquisition, storage, and usage can limit cellular energy availability and may influence resourceallocation tradeoffs even when environmental nutrients are plentiful. Here, we utilized Drosophila mitochondrial– nuclear genotypes to test whether disrupted mitochondrial function interferes with nutrient-sensing pathways, and whether this disruption has consequences for tradeoffs between immunity and fecundity. We found that an energetically-compromised genotype was relatively resistant to rapamycin—a drug that targets nutrient-sensing pathways and mimics resource limitation. Dietary …

Energy Demand And The Context-Dependent Effects Of Genetic Interactions Underlying Metabolism, Luke A. Hoekstra, Cole R. Julick, Katelyn M. Mika, Kristi L. Montooth

School of Biological Sciences: Faculty Publications

Genetic effects are often context dependent, with the same genotype differentially affecting phenotypes across environments, life stages, and sexes.We used an environmental manipulation designed to increase energy demand during development to investigate energy demand as a general physiological explanation for context-dependent effects of mutations, particularly for those mutations that affect metabolism. We found that increasing the photoperiod during which Drosophila larvae are active during development phenocopies a temperature-dependent developmental delay in a mitochondrial-nuclear genotype with disrupted metabolism. This result indicates that the context-dependent fitness effects of this genotype are not specific to the effects of temperature and may generally result …

Evolutionary Origins Of Vocal Mimicry In Songbirds, Maria Goller, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Vocal learning is an important behavior in oscines (songbirds). Some songbird species learn heterospecific sounds as well as conspecific vocalizations. The emergence of vocal mimicry is necessarily tied to the evolution of vocal learning, as mimicry requires the ability to acquire sounds through learning. As such, tracking the evolutionary origins of vocal mimicry may provide insights into the causes of variation in song learning programs among songbirds. We compiled a database of known vocal mimics that comprised 339 species from 43 families. We then traced the evolutionary history of vocal mimicry across the avian phylogeny using ancestral trait reconstruction on …

Time-Lagged Effects Of Weather On Plant Demography: Drought And Astragalus Scaphoides, Brigitte Tenhumberg, Elizabeth E. Crone, Satu Ramula, Andrew J. Tyre

School of Biological Sciences: Faculty Publications

Temperature and precipitation determine the conditions where plant species can occur. Despite their significance, to date, surprisingly few demographic field studies have considered the effects of abiotic drivers. This is problematic because anticipating the effect of global climate change on plant population viability requires understanding how weather variables affect population dynamics. One possible reason for omitting the effect of weather variables in demographic studies is the difficulty in detecting tight associations between vital rates and environmental drivers. In this paper, we applied Functional Linear Models (FLMs) to long-term demographic data of the perennial wildflower, Astragalus scaphoides, and explored sensitivity of …

Near Infrared Fluorescent Single Walled Carbon Nanotubes As Tissue Localizable Biosensors, Nicole M. Iverson, Michael S. Strano, Nigel F. Strano, Thomas P. Mcnicholas

Department of Agricultural and Biological Systems Engineering: Faculty Publications

A nanosensor for detecting an analyte can include a sub strate, a photoluminescent nanostructure, and a polymer interacting with the photoluminescent nanostructure. The nanosensor can be used in in vivo for biomedical applications.

Evaluation Of Critical Nitrogen And Phosphorus Models For Maize Under Full And Limited Irrigation Conditions, Koffi Djaman, Suat Irmak

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Proper nitrogen (N) fertiliser application rates and timing of application, coupled with optimum irrigation management can improve the sustainability of maize production and reduce the risk of environmental contamination by nutrients. The impact of full and limited irrigation and rainfed conditions on in-season maize (Zea mays L.) shoot biomass nutrient concentration and critical N and phosphorus (P) indices were evaluated using a combination of measured nutrients and critical N and P models in south central Nebraska in 2009 and 2010. Four irrigation treatments [fully-irrigated treatment (FIT), 75% FIT, 60% FIT and 50% FIT) and rainfed] were imposed. Irrigation regimes …

Impact Of Vegetative Treatment Systems On Multiple Measures Of Antibiotic Resistance In Agricultural Wastewater, Lisa M. Durso, Daniel N. Miller, Christopher G. Henry

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Wastewater is an important vector of antibiotic resistant bacteria and antibiotic resistance genes (ARB/G). While there is broad agreement that ARB/G from agricultural (ag) wastewaters can be transported through the environment and may contribute to untreatable infectious disease in humans and animals, there remain large knowledge gaps surrounding applied details on the types and amounts of ARB/G associated with different agricultural wastewater treatment options and different ag production systems. This study evaluates a vegetative treatment system (VTS) built to treat the wastewater from a beef cattle feedlot. Samples were collected for three years, and plated on multiple media types to …