Digital Commons Network^™

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 …

Ecoevo-Maps: An Ecology And Evolution Assessment For Introductory Through Advanced Undergraduates, Mindi M. Summers, Brian A. Couch, Jennifer K. Knight, Sara E. Brownell, Alison J. Crowe, Katharine Semsar, Christian D. Wright, Michelle K. Smith

School of Biological Sciences: Faculty Publications

A new assessment tool, Ecology and Evolution–Measuring Achievement and Progression in Science or EcoEvo-MAPS, measures student thinking in ecology and evolution during an undergraduate course of study. EcoEvo-MAPS targets foundational concepts in ecology and evolution and uses a novel approach that asks students to evaluate a series of predictions, conclusions, or interpretations as likely or unlikely to be true given a specific scenario. We collected evidence of validity and reliability for EcoEvo-MAPS through an iterative process of faculty review, student interviews, and analyses of assessment data from more than 3000 students at 34 associate’s-, bachelor’s-, master’s-, and doctoral-granting institutions. The …

Rnai Doxxes Segregation Distorters On The X, Justin P. Blumenstiel, Colin D. Meiklejohn

School of Biological Sciences: Faculty Publications

Species with chromosomal sex determination are susceptible to an evolutionary tug-of-war over sex chromosome segregation. RNA silencing has been proposed to play a role in this intragenomic conflict. Reporting in Developmental Cell, Lin et al. (2018) demonstrate that RNA interference is key to this conflict as a genome defender. ... This work from Lin et al. (2018) provides exciting new evidence that RNA silencing may play a special role as a genome defense against native genes gone rogue. It will be interesting to see how these evolutionary games mediated by RNA silencing influence germline evolution and the dynamics of speciation.

What Types Of Instructional Shifts Do Students Experience? Investigating Active Learning In Science, Technology, Engineering, And Math Classes Across Key Transition Points From Middle School To The University Level, Kenneth Akiha, Emilie Brigham, Brain A. Couch, Justin Lewin, Marilyne Stains, Mackenzie R. Stetzer, Erin L. Vinson, Michelle K. Smith

School of Biological Sciences: Faculty Publications

Despite the need for a strong Science, Technology, Engineering, and Math (STEM) workforce, there is a high attrition rate for students who intend to complete undergraduate majors in these disciplines. Students who leave STEM degree programs often cite uninspiring instruction in introductory courses, including traditional lecturing, as a reason. While undergraduate courses play a critical role in STEM retention, little is understood about the instructional transitions students encounter upon moving from secondary to post-secondary STEM courses. This study compares classroom observation data collected using the Classroom Observation Protocol for Undergraduate STEM from over 450 middle school, high school, introductory-level university, …

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 …

Binary-State Speciation And Extinction Method Is Conditionally Robust To Realistic Violations Of Its Assumptions, Andrew G. Simpson, Peter J. Wagner, Scott L. Wing, Charles B. Fenster

School of Biological Sciences: Faculty Publications

Phylogenetic comparative methods allow us to test evolutionary hypotheses without the benefit of an extensive fossil record. These methods, however, make simplifying assumptions, among them that clades are always increasing or stable in diversity, an assumption we know to be false. This study simulates hypothetical clades to test whether the Binary State Speciation and Extinction (BiSSE) method can be used to correctly detect relative differences in diversification rate between ancestral and derived character states even as net diversification rates are declining overall. We simulate clades with declining but positive diversification rates, as well those in which speciation rates decline below …

Evidence For Trait-Based Dominance In Occupancy Among Fossil Taxa And The Decoupling Of Macroecological And Macroevolutionary Success, Peter Wagner, Roy E. Plotnick, S. Kathleen Lyons

School of Biological Sciences: Faculty Publications

Biological systems provide examples of differential success among taxa, from ecosystems with a few dominant species (ecological success) to clades that possess far more species than sister clades (macroevolutionary success). Macroecological success, the occupation by a species or clade of an unusually high number of areas, has received less attention. If macroecological success reflects heritable traits, then successful species should be related. Genera composed of species possessing those traits should occupy more areas than genera with comparable species richness that lack such traits. Alternatively, if macroecological success reflects autapomorphic traits, then generic occupancy should be a by-product of species richness …

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.

Nitric Oxide Sensors For Biological Applications, Nicole M. Iverson, Eric M. Hofferber, Joseph A. Stapleton

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nitric oxide (NO) is an essential signaling molecule within biological systems and is believed to be involved in numerous diseases. As a result of NO’s high reaction rate, the detection of the concentration of NO, let alone the presence or absence of the molecule, is extremely difficult. Researchers have developed multiple assays and probes in an attempt to quantify NO within biological solutions, each of which has advantages and disadvantages. This review highlights many of the current NO sensors, from those that are commercially available to the newest sensors being optimized in research labs, to assist in the understanding and …

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 …

Phenotypic Responses To Interspecies Competition And Commensalism In A Naturally Derived Microbial Co-Culture, Nymul Khan, Yukari Maezato, Ryan S. Mcclure, Colin J. Brislawn, Jennifer M. Mobberley, Nancy Isern, William B. Chrisler, Lye Meng Markillie, Brett M. Barney, Hyun-Seob Song, William C. Nelson, Hans C. Bernstein

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The fundamental question of whether different microbial species will co-exist or compete in a given environment depends on context, composition and environmental constraints. Model microbial systems can yield some general principles related to this question. In this study we employed a naturally occurring co-culture composed of heterotrophic bacteria, Halomonas sp. HL-48 and Marinobacter sp. HL- 58, to ask two fundamental scientific questions: 1) how do the phenotypes of two naturally co-existing species respond to partnership as compared to axenic growth? and 2) how do growth and molecular phenotypes of these species change with respect to competitive and commensal interactions? We …

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 …

Special Issue: Microbial Community Modeling: Prediction Of Microbial Interactions And Community Dynamics, Hyun-Seob Song

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Microbial communities are networks of species, the interaction structure of which dynamically reorganizes in a varying environment. Even in a static condition, community dynamics are often difficult to predict due to highly nonlinear interspecies interactions. Understanding the fundamental principles of microbial interactions is therefore key for predicting and harnessing community function and properties. As extensively reviewed previously, mathematical models and computational methods that can predictively link interactions to community behaviors are indispensable tools for achieving this goal [1].

Impacts Of Cover Crops On Soil Physical Properties: Field Capacity, Permanent Wilting Point, Soil-Water Holding Capacity, Bulk Density, Hydraulic Conductivity, And Infiltration, Suat Irmak, Vivek Sharma, Ali T. Mohammed, Koffi Djaman

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Field experiments were carried out to quantify the effects of cover cropping on soil physical properties. Field capacity (FC), permanent wilting point (PWP), soil-water holding capacity (SWHC), bulk density (  b), saturated and unsaturated hydraulic conductivity (Ks and Kus, respectively), and infiltration rates were measured and compared for four land cover treatments [cover crop without seed maize (CC), seed maize followed by cover crop (SCCC), bare soil, and seed maize without cover crop (SC)] in three large-scale production fields (~64 ha each) with silt loam soil in the 2012-2013, 2013-2014, 2014-2015, and 2015-2016 cover crop growing seasons. All production …

Synthesis, Secretion, And Perception Of Abscisic Acid Regulates Stress Responses In Chlorella Sorokiniana, Maya Khasin, Rebecca E. Cahoon, Sophie Alvarez, Richard Beckeris, Seong-Il Eyun, Qidong Jia, Jean-Jack Riethoven, Kenneth Nickerson, Wayne R. Riekhof

Kenneth Nickerson Papers

Abscisic acid (ABA) is a phytohormone that has been extensively characterized in higher plants for its roles in seed and bud dormancy, leaf abscission, and stress responses. Genomic studies have identified orthologs for ABA-related genes throughout the Viridiplantae, including in unicellular algae; however, the role of ABA in algal physiology has not been characterized, and the existence of such a role has been a matter of dispute. In this study, we demonstrate that ABA is involved in regulating algal stress responses. Chlorella sorokiniana strain UTEX 1230 contains genes orthologous to those of higher plants which are essential for ABA …

Temporal Variation In Predation Risk May Explain Daily Rhythms Of Foraging Behavior In An Orb-Weaving Spider, J. Colton Watts, Thomas C. Jones, Ashley Herrig, Madeleine Miller, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Daily rhythms occur in numerous physiological and behavioral processes across an immense diversity of taxa, but there remain few cases in which mechanistic links between rhythms of trait expression and organismal fitness have been established. We construct a dynamic optimization model to determine whether risk allocation provides an adaptive explanation for the daily foraging rhythm observed in many species using the orb-weaving spider Cyclosa turbinata as a case study. Our model predicts that female C. turbinata should generally start foraging at lower levels of energy reserves (i.e., should be less bold) during midday when predators are most abundant. We also …

Presence Of Fruits Decreases Probability Of Retaining Flowers In A Sequentially Flowering Plant, Shivani Jadeja, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Both intrinsic and extrinsic plant processes affect the fate of flowers along an inflorescence in sequentially flowering plants. We investigated whether the intrinsic process of competition for limited resource between fruits and flowers owing to resource preemption or sink strength of basal fruits, or architectural effects due to posi- tional differences in the probability of retaining flowers, explains a lower probability of retaining distal flowers inYucca glauca. Further, we investigated how the extrinsic process of seed herbivory interacts with the plant’s intrinsic processes of flower retention. We carried out a field experiment to compare flower retention among nine combi- nations …

Focused Electron-Beam-Induced Deposition For Fabrication Of Highly Durable And Sensitive Metallic Afm-Ir Probes, Wen Qian, Shuo Sun, Jingfeng Song, Charles Nguyen, Stephen Ducharme, Joesph A. Turner

Stephen Ducharme Publications

We report on the fabrication of metallic, ultra-sharp atomic force microscope tips for localized nanoscale infrared (IR) spectrum measurements by using focused electron-beam-induced deposition of platinum or tungsten. The tip length can be controlled by changing the duration time of the electron beam. Probes of 12.0 ± 5.0 nm radius-of-curvature can be routinely produced with high repeatability and near-100% yield. The near-field-enhancement appears stronger at the extremity of the metallic tip, compared with commercial pristine silicon-nitride probe tip. Finally, the performance of the modified metallic tips is demonstrated by imaging PVDF and PMMA thin films, which shows that spatial resolution …

Real Potential, Jennifer Mckitrick

Department of Philosophy: Faculty Publications

There's a student in my philosophy class who has "real potential." I might express this thought in any of the following ways: "She is potentially a philosopher"; "She is a potential philosopher"; "She has the potential to be a philosopher." The first way uses a cognate of "potential" as an adverb to modify "is." The second ways uses "potential" as an adjective to modify "philosopher." However, the third way uses "potential" as a noun to refer to something that the student has. What kind of thing is this potential? One worry about even asking this question is that this nominalization …

Feminist Metaphysics: Can This Marriage Be Saved?, Jennifer Mckitrick

Department of Philosophy: Faculty Publications

Feminist metaphysics is simultaneously feminist theorizing and metaphysics. Part of feminist metaphysics concerns social ontology and considers such questions as, What is the nature of social kinds, such as genders? Feminist metaphysicians also consider whether gendered perspectives influence metaphysical theorizing; for example, have approaches to the nature of the self or free will been conducted from a masculinist perspective, and would a feminist perspective yield different theories? Some feminist metaphysicians develop metaphysical theories with the aim of furthering certain social goals, such as gender equality.

Despite these and other intriguing research projects, feminist metaphysics faces challenges from two flanks: one …

Neonchocotyle Violantei N. Sp. (Monogenea, Hexabothriidae) From Pseudobatos Lentiginosus (Rhinopristiformes, Rhinobatidae) Of Yucatán, Gulf Of Mexico = Neonchocotyle Violantei N. Sp. (Monogenea, Hexabothriidae) Do Pseudobatos Lentiginosus (Rhinopristiformes, Rhinobatidae) De Yucatán, Golfo Do México, Guadalupe Quiterio-Rendon, Scott Monks, Griselda Pulido-Flores

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Abstract

Neonchocotyle violantei n. sp. (Monogenea: Hexabothriidae) infects the gill of the Atlantic guitarfish, Pseudobatos lentiginosus (Rhinopristiformes, Rhinobatidae) from littoral waters of Celestún, Yucatán, Mexico. It is assigned to Neonchocotyle because it has, among other features, an asymmetrical haptor, a seminal receptacle, a smooth oötype, and an egg with two elongate filaments. It differs from Neonchocotyle pastinacae, the only congener, by having a small body (821 long by 315 wide, length to width = 2.6:1), two pairs of microhooks between the haptoral appendix suckers, extracaecal (submarginal) vaginal pores, and 5-9 testes. This is the first record of a species …

A New Species Of Acanthobothrium (Eucestoda: Onchobothriidae) In Aetobatus Cf. Narinari (Myliobatidae) From Campeche, México = Uma Nova Espécie De Acanthobothrium (Eucestoda: Onchobothriidae) Em Aetobatus Cf. Narinari (Myliobatidae) De Campeche, México, Erick Rodríguez-Ibarra, Griselda Pulido-Flores, Juan Violante-González, Scott Monks

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Abstract

The helminthological examination of nine individuals of Aetobatus cf. narinari (spotted eagle ray; raya pinta; arraia pintada) revealed the presence of an undescribed species of cestode of the genus Acanthobothrium. The stingrays were collected from four locations in México: Laguna Términos, south of Isla del Carmen and the marine waters north of Isla del Carmen and Champotón, in the State of Campeche, and Isla Holbox, State of Quintana Roo. The new species, nominated Acanthobothrium marquesi, is a category 3 species (i.e, the strobila is long, has more than 50 proglottids, the numerous testicles greater than 80, and has …

Diversity And Phylogenetic Relationships Of European Species Of Crepidostomum Braun, 1900 (Trematoda: Allocreadiidae) Based On Rdna, With Special Reference To Crepidostomum Oschmarini Zhokhov & Pugacheva, 1998, Romualda Petkevičiūtė, Virmantas Stunžėnas, Alexander E. Zhokhov, Larisa G. Poddubnaya, Gražina Stanevičiūtė

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Background

Within the genus Crepidostomum Braun, 1900, identification of species and taxonomic decisions made only on the basis of adult morphology have resulted in great problems associated with evaluating actual diversity and validity of species. Life cycle data, while equal in importance to adult characters, are scarce, controversial or incomplete for most Crepidostomum spp. In this study, rDNA sequences generated from adult and larval Crepidostomum spp. and some other allocreadiid species were analyzed to reveal the diversity and phylogenetic relationships of the species and their host range. Detailed morphological description based on light microscopy, SEM tegumental surface topography and genetic …

Using Watershed Boundaries To Map Adverse Health Outcomes: Examples From Nebraska, Usa, Brittany Corley, Shannon L. Bartelt-Hunt, Eleanor Rogan, Donald Coulter, John Sparks, Lorena Baccaglini, Madeline Howell, Sidra Liaquat, Rex Commack, Alan S. Kolok

Department of Civil and Environmental Engineering: Faculty Publications

In 2009, a paper was published suggesting that watersheds provide a geospatial platform for establishing linkages between aquatic contaminants, the health of the environment, and human health. This article is a follow-up to that original article. From an environmental perspective, watersheds segregate landscapes into geospatial units that may be relevant to human health outcomes. From an epidemiologic perspective, the watershed concept places anthropogenic health data into a geospatial framework that has environmental relevance. Research discussed in this article includes information gathered from the literature, as well as recent data collected and analyzed by this research group. It is our contention …

Sustainable Waste-To-Energy Technologies: Bioelectrochemical Systems, Rami Ziara, Bruce Dvorak, Jeyamkondan Subbiah

Department of Civil and Environmental Engineering: Faculty Publications

The food industry produces a large amount of waste and wastewater, of which most of the constituents are carbohydrates, proteins, lipids, and organic fibers. Therefore food wastes are highly biodegradable and energy rich. Bioelectrochemical systems (BESs) are systems that use microorganisms to biochemically catalyze complex substrates into useful energy products, in which the catalytic reactions take place on electrodes. Microbial fuel cells (MFCs) are a type of bioelectrochemical systems that oxidize substrates and generate electric current. Microbial electrolysis cells (MECs) are another type of bioelectrochemical systems that use an external power source to catalyze the substrate into by-products such as …

Three-Dimensional Modeling Of Nitrate-N Transport In Vadose Zone: Roles Of Soil Heterogeneity And Groundwater Flux, Simin Akbariyeh, Shannon L. Bartelt-Hunt, Daniel D. Snow, Xu Li, Zhenghong Tang, Yusong Li

Department of Civil and Environmental Engineering: Faculty Publications

Contamination of groundwater from nitrogen fertilizers in agricultural lands is an important environmental and water quality management issue. It is well recognized that in agriculturally intensive areas, fertilizers and pesticides may leach through the vadose zone and eventually reach groundwater. While numerical models are commonly used to simulate fate and transport of agricultural contaminants, few models have considered a controlled field work to investigate the influence of soil heterogeneity and groundwater flow on nitrate-N distribution in both root zone and deep vadose zone.

In this work, a numerical model was developed to simulate nitrate-N transport and transformation beneath a center …

Comparative Study On The Performance Of Anaerobic And Aerobic Biotrickling Filter For Removal Of Chloroform, Bineyam Mezgebe, Keerthisaranya Palanisamy, George A. Sorial, Endalkachew Sahle-Demessie, Ashraf Aly Hassan, Jingrang Lu

Department of Civil and Environmental Engineering: Faculty Publications

Use of biotrickling filter (BTF) for gas phase treatment of volatile trihalomethanes (THMs) stripped from water treatment plants could be an attractive treatment option. The aim of this study is to use laboratory-scale anaerobic BTF to treat gaseous chloroform (recalcitrant to biological transformation) as a model THM and compare results with aerobic BTF. Additional investigations were conducted to determine the microbial diversity present within the BTFs. Chloroform is a hydrophobic volatile THM known to be difficult to biodegrade. To improve the degradation process, ethanol was used as a cometabolite at a different ratio to chloroform. The experimental plan was designed …