Life Sciences Commons^™

A 100-M-Scale Modeling Study Of A Gale Event On The Lee Side Of A Long Narrow Mountain, Halie Xue, Jian Li, Tingting Qian, Hongping Gu

Plants, Soils, and Climate Faculty Publications

In this study, a gale event that occurred on the lee side of a long narrow mountain was investigated, together with the associated mountain flows, using a realistic-case large-eddy simulation (LES) that is based on the Weather Research and Forecasting Model. The mountain is located on the southeastern Tibetan Plateau, where approximately 58 gales occur annually, mostly in the afternoons during the winter season. Benefitting from realistic topography and high horizontal resolution as fine as 111 m, the LES can replicate features similar to the wind fields observed during the gale period. Investigation of the early morning wind structure over …

Green Strategic Planning Approach For International Shipping Activities, Xiaofang Wu, Luoping Zhang, Huan Feng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Sustainability is a long-term and ultimate goal for international shipping, although it is slowly making progress. The shipping perspective that moves away from “port-to-port” operations to “door-to-door” services also requires international shipping to take a long-term and holistic view instead of fragmented efforts. How to achieve the long-term sustainability goal becomes a key issue for door-to-door international shipping. Hence, green strategic planning for door-to-door international shipping was proposed with green development that puts forward the eco-centric point of view as its basic theory for sustainability. This study used a strategic decision-making approach, a so-called multi-dimensional decision-making (MDDM), coupled with the …

Potential Distribution Of Six North American Higher-Attine Fungus-Farming Ant (Hymenoptera: Formicidae) Species, Sarah F. Senula, Joseph T. Scavetta, Joshua A. Banta, Ulrich G. Mueller, Jon N. Seal, Katrin Kellner

Biology Faculty Publications and Presentations

Ants are among the most successful insects in Earth’s evolutionary history. However, there is a lack of knowledge regarding range-limiting factors that may influence their distribution. The goal of this study was to describe the environmental factors (climate and soil types) that likely impact the ranges of five out of the eight most abundant Trachymyrmex species and the most abundant Mycetomoellerius species in the United States. Important environmental factors may allow us to better understand each species’ evolutionary history. We generated habitat suitability maps using MaxEnt for each species and identified associated most important environmental variables. We quantified niche overlap …

Divergent Phenotypic Response Of Rice Accessions To Transient Heat Stress During Early Seed Development, Puneet Paul, Balpreet K. Dhatt, Jaspreet Sandhu, Waseem Hussain, Larissa Irvin, Gota Morota, Paul E. Staswick, Harkamal Walia

Department of Agronomy and Horticulture: Faculty Publications

Increasing global surface temperatures is posing a major food security challenge. Part of the solution to address this problem is to improve crop heat resilience, especially during grain development, along with agronomic decisions such as shift in planting time and increasing crop diversification. Rice is a major food crop consumed by more than 3 billion people. For rice, thermal sensitivity of reproductive development and grain filling is well-documented, while knowledge concerning the impact of heat stress (HS) on early seed development is limited. Here, we aim to study the phenotypic variation in a set of diverse rice accessions for elucidating …

A Bifunctional Atpase Drives Tad Pilus Extension And Retraction, Courtney K. Ellison, Jingbo Kan, Jennifer L. Chlebek, Katherine R. Hummels, GaёL Panis, Patrick H. Viollier, Nicolas Biais, Ankur B. Dalia, Yves V. Brun

Publications and Research

A widespread class of prokaryotic motors powered by secretion motor adenosine triphosphatases (ATPases) drives the dynamic extension and retraction of extracellular fibers, such as type IV pili (T4P). Among these, the tight adherence (tad) pili are critical for surface sensing and biofilm formation. As for most other motors belonging to this class, how tad pili retract despite lacking a dedicated retraction motor ATPase has remained a mystery. Here, we find that a bifunctional pilus motor ATPase, CpaF, drives both activities through adenosine 5′-triphosphate (ATP) hydrolysis. We show that mutations within CpaF result in a correlated reduction in the rates of …

Succession Of Microbial Populations And Nitrogen-Fixation Associated With The Biodegradation Of Sediment-Oil-Agglomerates Buried In A Florida Sandy Beach, Boryoung Shin, Ioana Bociu, Max Kolton, Markus Huettel, Joel E Kostka

C-IMAGE Publications

The Deepwater Horizon (DWH) oil spill contaminated coastlines from Louisiana to Florida, burying oil up to 70 cm depth in sandy beaches, posing a potential threat to environmental and human health. The dry and nutrient-poor beach sand presents a taxing environment for microbial growth, raising the question how the biodegradation of the buried oil would proceed. Here we report the results of an in-situ experiment that (i) characterized the dominant microbial communities contained in sediment oil agglomerates (SOAs) of DWH oil buried in a North Florida sandy beach, (ii) elucidated the long-term succession of the microbial populations that developed in …

Defects In Mating Behavior And Tail Morphology Are The Primary Cause Of Sterility In Caenorhabditis Elegans Males At High Temperature, Emily M. Nett, Nicholas B. Sepulveda, Lisa N. Petrella

Biological Sciences Faculty Research and Publications

Reproduction is a fundamental imperative of all forms of life. For all the advantages sexual reproduction confers, it has a deeply conserved flaw: it is temperature sensitive. As temperatures rise, fertility decreases. Across species, male fertility is particularly sensitive to elevated temperature. Previously, we have shown in the model nematode Caenorhabditis elegans that all males are fertile at 20°C, but almost all males have lost fertility at 27°C. Male fertility is dependent on the production of functional sperm, successful mating and transfer of sperm, and successful fertilization post-mating. To determine how male fertility is impacted by elevated temperature, we analyzed …

Management Controls The Net Greenhouse Gas Outcomes Of Growing Bioenergy Feedstocks On Marginally Productive Croplands, Virginia L. Jin, Marty Schmer, Catherine E. Stewart, Robert B. Mitchell, Candiss O. Williams, Brian J. Wienhold, Gary Varvel, Ronald F. Follett, John Kimble, Kenneth P. Vogel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Bio-based energy is key to developing a globally sustainable low-carbon economy. Lignocellulosic feedstock production on marginally productive croplands is expected to provide substantial climate mitigation benefits, but long-term field research comparing greenhouse gas (GHG) outcomes during the production of annual versus perennial crop-based feedstocks is lacking. Here, we show that long-term (16 years) switchgrass (Panicum virgatum L.) systems mitigate GHG emissions during the feedstock production phase compared to GHG-neutral continuous corn (Zea mays L.) under conservation management on marginally productive cropland. Increased soil organic carbon was the major GHG sink in all feedstock systems, but net agronomic GHG outcomes …

A Model For The Prediction Of Antimicrobial Resistance In Escherichia Coli Based On A Comparative Evaluation Of Fatty Acid Profiles, Randal S. Stahl, Bledar Bisha, Sebabrata Mahapatra, Jeffrey C. Chandler

United States Department of Agriculture Wildlife Services: Staff Publications

Antimicrobial resistance is a threat to agricultural production and public health. In this proof-of-concept study, we investigated predicting antimicrobial sensitive/resistant (S/R) phenotypes and host sources of Escherichia coli (n = 128) based on differential fatty acid abundance. Myristic (14:0), pentadecanoic acid (15:0), palmitic (16:0), elaidic (18:19) and steric acid (18:0) were significantly different (α = 0.05) using a two-way ANOVA for predicting nalidixic acid, ciprofloxacin, aztreonam, cefatoxime, and ceftazidime S/R phenotypes. Additionally, analyses of palmitoleic (16:1), palmitic acid (16:0), methyl palmitate (i-17:0), and cis-9,10-methyleneoctadecanoic acid (19:0Δ) showed these markers were significantly different (α = 0.05) between isolates obtained from cattle …

Representative Economic Budgets For Nebraska Cow Herds, Glennis Mcclure, Jay Parsons

Cornhusker Economics

In 2017, the University of Nebraska-Lincoln Institute of Agricultural and Natural Resources (IANR) and Nebraska Extension made a commitment to implement a multidisciplinary Beef Systems Initiative (BSI). BSI is administered by the Center for Grassland Studies and is comprised of six projects designed to develop and support implementation of beef production systems that optimize feed resource use, natural resource conservation, and producer success in Nebraska through improved management of perennial grasslands and systems of integrated crop-beef cattle production. In addition to BSI, a parallel project funded by the Foundation for Food and Agriculture Research (FFAR) is studying the best practices …

A "Choose-Your-Own" Classroom-Based Activity That Promotes Scientific Inquiry About Rna Interference, Jeremy L. Hsu

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

RNA interference (RNAi), the process that results in the degradation of a target gene’s mRNA, is a fundamental part of eukaryotic gene regulation and is also an important molecular technique that allows for experimental manipulation of gene expression without altering DNA sequences. Despite the importance of RNAi, there have been relatively few lecture-based activities designed to teach about the consequences of this process and counter common misconceptions. I present here an inquiry-based activity that is centered around a “choose your own experiment” design where students generate hypotheses and critically evaluate their ideas by choosing several simulated experiments. The activity presents …

Isolation Of Metrosideros (`Ohi`A) Taxa On O`Ahu Increases With Elevation And Extreme Environments, Elizabeth A. Stacy, Tomoko Sakishima, Heaven Tharp, Neil Snow

Life Sciences Faculty Research

Species radiations should be facilitated by short generation times and limited dispersal among discontinuous populations. Hawaii’s hyper-diverse, landscape-dominant tree, Metrosideros, is unique among the islands’ radiations for its massive populations that occur continuously over space and time within islands, its exceptional capacity for gene flow by both pollen and seed, and its extended life span (ca. >650 years). Metrosideros shows the greatest phenotypic and microsatellite DNA diversity on O`ahu, where taxa occur in tight sympatry or parapatry in mesic and montane wet forest on 2 volcanoes. We document the nonrandom distributions of 12 taxa (including unnamed morphotypes) along elevation gradients, …

Genetic Taster Status As A Mediator Of Neural Activity And Swallowing Mechanics In Healthy Adults, Angela M. Dietsch, Ross M. Westemeyer, William G. Pearson Jr., Douglas H. Schultz

Center for Brain, Biology, and Behavior: Faculty and Staff Publications

As part of a larger study examining relationships between taste properties and swallowing, we assessed the influence of genetic taster status (GTS) on measures of brain activity and swallowing physiology during taste stimulation in healthy men and women. Twenty-one participants underwent videofluoroscopic swallowing study (VFSS) and functional magnetic resonance imaging (fMRI) during trials of high-intensity taste stimuli. The precisely formulated mixtures included sour, sweet-sour, lemon, and orange taste profiles and unflavored controls. Swallowing physiology was characterized via computational analysis of swallowing mechanics plus other kinematic and temporal measures, all extracted from VFSS recordings. Whole-brain analysis of fMRI data assessed blood …

Seed‐To‐Seedling Transitions Exhibit Distance‐Dependent Mortality But No Strong Spacing Effects In A Neotropical Forest, Philippe Marchand, Liza S. Comita, S. Joseph Wright, Richard Condit, Stephen P. Hubbell, Noelle G. Beckman

Biology Faculty Publications

Patterns of seed dispersal and seed mortality influence the spatial structure of plant communities and the local coexistence of competing species. Most seeds are dispersed in proximity to the parent tree, where mortality is also expected to be the highest, because of competition with siblings or the attraction of natural enemies. Whereas distance‐dependent mortality in the seed‐to‐seedling transition was often observed in tropical forests, few studies have attempted to estimate the shape of the survival‐distance curves, which determines whether the peak of seedling establishment occurs away from the parent tree (Janzen–Connell pattern) or if the peak attenuates but remains at …

Alanyl-Trna Synthetase Quality Control Prevents Global Dysregulation Of The Escherichia Coli Proteome, Paul Kelly, Nicholas Backes, Kyle Mohler, Christopher Buser, Arundhati Kavoor, Jesse Rinehart, Gregory Phillips, Michael Ibba

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Mechanisms have evolved to prevent errors in replication, transcription, and translation of genetic material, with translational errors occurring most frequently. Errors in protein synthesis can occur at two steps, during tRNA aminoacylation and ribosome decoding. Recent advances in protein mass spectrometry have indicated that previous reports of translational errors have potentially underestimated the frequency of these events, but also that the majority of translational errors occur during ribosomal decoding, suggesting that aminoacylation errors are evolutionarily less tolerated. Despite that interpretation, there is evidence that some aminoacylation errors may be regulated, and thus provide a benefit to the cell, while others …

Embryogenic Cell Suspensions For High-Capacity Genetic Transformation And Regeneration Of Switchgrass (Panicum Virgatum L.), Christine A. Ondzighi-Assoume, Jonathan D. Willis, Wilson Kihugu Ouma, Sara M. Allen, Zachary King, Wayne A. Parrott, Wusheng Liu, Jason N. Burris, Scott C. Lenaghan, C. Neal Stewart

Agricultural and Environmental Sciences Faculty Research

Background

Switchgrass (Panicum virgatum L.), a North American prairie grassland species, is a potential lignocellulosic biofuel feedstock owing to its wide adaptability and biomass production. Production and genetic manipulation of switchgrass should be useful to improve its biomass composition and production for bioenergy applications. The goal of this project was to develop a high-throughput stable switchgrass transformation method using Agrobacterium tumefaciens with subsequent plant regeneration.

Results

Regenerable embryogenic cell suspension cultures were established from friable type II callus-derived inflorescences using two genotypes selected from the synthetic switchgrass variety ‘Performer’ tissue culture lines 32 and 605. The cell suspension cultures …

Sixteen Years Of Social And Ecological Dynamics Reveal Challenges And Opportunities For Adaptive Management In Sustaining The Commons, Josh Eli Cinner, J. D. Lau, Andrew G. Bauman, David A. Feary, Fraser A. Januchowski-Hartley, C. A. Rojas, M. L. Barnes, B. J. Bergseth, E. Shum, R. Lahari, J. Ben, N. A. J. Graham

Marine & Environmental Sciences Faculty Articles

Efforts to confront the challenges of environmental change and uncertainty include attempts to adaptively manage social–ecological systems. However, critical questions remain about whether adaptive management can lead to sustainable outcomes for both ecosystems and society. Here, we make a contribution to these efforts by presenting a 16-y analysis of ecological outcomes and perceived livelihood impacts from adaptive coral reef management in Papua New Guinea. The adaptive management system we studied was a customary rotational fisheries closure system (akin to fallow agriculture), which helped to increase the biomass of reef fish and make fish less wary (more catchable) relative to openly …

Assessing The Blood Meal Hosts Of Culex Quinquefasciatus And Aedes Taeniorhynchus In Isla Santa Cruz, Galápagos, Samoa Asigau, Sawsan Salah, Patricia Parker

Biology Department Faculty Works

No abstract provided.

Treehoppers (Hemiptera: Aetalionidae And Membracidae) From Madre De Dios Region, Peru, Chung-Ping Lin, Munetoshi Maruyama, Jo-Fan Wang, Paige E. Miller, Caroline S. Chaboo

Department of Entomology: Faculty Publications

A list of treehoppers (Aetalionidae and Membracidae) is presented from Madre de Dios region at the southeastern Amazon basin in Peru. The treehopper specimens were collected as by-catch in a survey of the beetles in the Villa Carmen Biological Station and Los Amigos Biological Station. The list comprises 44 species, 31 genera, 16 tribes and 9 subfamilies. Ten genera are new records to Peru. The images of representative specimens of each identified species and genera are provided to facilitate the identification of the local treehopper fauna.

Resumen: Se presenta una lista de los membrácidos (Aetalionidae y Membracidae) de la región …

Commentary: Acute Effects Of Exercise Mode On Arterial Stiffness And Wave Reflection In Healthy Young Adults: A Systematic Review And Meta-Analysis, J. Derek Kingsley, Yu Lun Tai

Health & Human Performance Faculty Publications and Presentations

No abstract provided.

A Self-Marker-Like Protein Governs Hemocyte Allorecognition In Halocynthia Roretzi, Masaki Ema, Taizo Okada, Miki Takahashi, Masato Uchiyama, Hideo Kubo, Hideaki Moriyama, Hitoshi Miyakawa, Midori Matsumoto

School of Biological Sciences: Faculty Publications

Background: Self-incompatibility, fusion/non-fusion reactions, and contact reactions (CRs) have all been identified as allorecognition phenomena in ascidians. CR is a reaction characteristic of the hemocytes of Halocynthia roretzi, whereby they release phenol oxidase (PO) upon contact with non-self hemocytes. Thus, these cells may represent a primitive form of the vertebrate immune system. In the present study, we focused on the CR of H. roretzi hemocytes and sought to identify self-marker proteins that distinguish between self and non-self cells.

Results: We initially generated a CR-inducing monoclonal antibody against the complete hemocyte membraneprotein complement (mAb11B16B10). This antibody was identified based on the …

Assessment Of Benthic Macrofauna Community Within Intertidal Mudflats - Hurds Cove, Lynnhaven River, Virginia, M. Lisa Kellogg, Jennifer C. Dreyer

Reports

A total of 30 samples were collected from eight locations in Hurds Cove, Lynnhaven River, VA. All samples were rinsed over a 500-μm mesh sieve and all material retained on the sieve was analyzed to determine benthic macrofaunal community identity, abundance and biomass. With the exception of one sample with relatively high biomass (50.68 g AFDW m-2) attributable to a single (Rangia cuneata), biomass across all locations was low, ranging from 0.16-0.67 g AFDW m-2. At five of the eight locations, all measurable biomass was contributed by polychaete worms. At the other three locations, polychaetes accounted for 45-57% of total …

Expanding Virginia"S Oyster Industry While Minimizing User Conflict - Interim Report (Year 2 Of 3), Roger L. Mann, Marcia Berman, James Wesson, Melissa Southworth, Tamia Rudnicky

Reports

This study seeks to assess the sustainability of the public oyster fishery and the expansion of hatchery dependent oyster aquaculture in the Virginia portion of the Chesapeake Bay. Previous analyses have suggested that limitations in available shell resources will ultimately drive the future of the public fishery. The expansion of intensive aquaculture, already apparent in the Bay, suggests sustainability will be contingent upon the availability of bottom space and/or a shift in practices that minimize user conflict in leased areas.

Assessing The Morphology Of Vesicles In Inhibitory Symmetric Synapses In Safety And Fear Conditions In The Rat Lateral Amygdala, Valerie Kress

Honors Scholar Theses

There is a significant lack of research on vesicle morphology in inhibitory synapses in the rat lateral amygdala. Published research focuses heavily on excitatory synapses in different parts of the rat brain and even this research rarely focuses on the different vesicle types in axons. It is reported that in these axons, synaptic vesicles traditionally contain neurotransmitters while small dense core vesicles contain active zone proteins and large dense core vesicles contain neuropeptides. This study aims to find correlations between vesicle morphology, location, contents, and potential function of each of the different types of vesicle in inhibitory axons.

After reviewing …

Vintage Report 2019: North Willamette Valley, Gregory V. Jones

Linfield University Wine Studies Reports

This report describes the impacts of climate and phenology on vintage for the North Willamette Valley in Oregon in 2019. A relatively mild early winter in 2018 was followed by a cold and wet second half of winter in 2019 and then a wet, but warm, spring. The growing season saw a few mild frosts during late April, but started off warmer than average, moderating through mid-vintage with fewer than average heat spikes. Near-record precipitation amounts during late June and early July brought increased disease pressure to the region. The vintage will be remembered for the early rains in September …

Postharvest Heat Treatments To Inhibit Penicillium Digitatum Growth And Maintain Quality Of Mandarin (Citrus Reticulata Blanco), Diana B. Queb-Gonzalez, Aurelio Lopez-Malo, María E. Sosa-Morales, Rossana Villa-Rojas

Department of Food Science and Technology: Faculty Publications

Use of fungicides is a common practice as a postharvest treatment to control fruit decay. Nowadays, environment-friendly technologies, such as heat treatments, are viable replacements. This study evaluated the effects of post-harvest heat treatments (traditional and microwave-assisted) on mandarins intentionally inoculated with Penicillium digitatum. For the studied heat treatments, the target temperature was 50C, which was held for 2.5 min. After heating, mandarins were cooled and stored at 25C for 13 days. MW treatments effectively prevented mold growth during storage, while HW only delayed it. Control mandarins (without treatment) showed the highest significant weight loss. Neither thermal treatment nor storage …

Not All Fuel-Reduction Treatments Degrade Biocrusts: Herbicides Cause Mostly Neutral To Positive Effects On Cover Of Biocrusts, Lea A. Condon, Margaret L. Gray

Ecology Center Publications

In response to increasing fire, fuel‐reduction treatments are being used to minimize large fire risk. Although biocrusts are associated with reduced cover of fire‐promoting, invasive grasses, the impact of fuel‐reduction treatments on biocrusts is poorly understood. We use data from a long‐term experiment, the Sagebrush Steppe Treatment Evaluation Project, testing the following fuel‐reduction treatments: mowing, prescribed fire, and the use of two herbicides: one commonly used to reduce shrub cover, tebuthiuron, and one commonly used to combat cheatgrass, imazapic. Looking at sites with high cover of biocrusts prior to treatments, we demonstrate positive effects of the herbicide, tebuthiuron on lichens …

A Novel And Green Nanoparticle Formation Approach To Forming Low-Crystallinity Curcumin Nanoparticles To Improve Curcumin’S Bioaccessibility, Ali Ubeyitogullari, Ozan Ciftci

Department of Food Science and Technology: Faculty Publications

Health-promoting effects of curcumin are well-known; however, curcumin has a very low bioavailability due to its crystalline structure. The main objective of this study was to develop a novel green nanoparticle formation method to generate low-crystallinity curcumin nanoparticles to enhance the bioavailability of curcumin. Nanoporous starch aerogels (NSAs) (surface area of 60 m2/g, pore size of 20 nm, density of 0.11 g/cm3, and porosity of 93%) were employed as a mold to produce curcumin nanoparticles with the help of supercritical carbon dioxide (SC-CO2). The average particle size of the curcumin nanoparticles was 66 nm. Impregnation into NSAs decreased the crystallinity …

Docosahexaenoic Acid Consumption Impedes Early Interferon- And Chemokine-Related Gene Expression While Suppressing Silica-Triggered Flaring Of Murine Lupus, Abby D. Benninghoff, Melissa A. Bates, Preeti S. Chauhan, Kathryn A. Wierenga, Kristen N. Gilley, Andrij Holian, Jack R. Harkema, James J. Pestka

Animal, Dairy, and Veterinary Science Faculty Publications

Exposure of lupus-prone female NZBWF1 mice to respirable crystalline silica (cSiO₂), a known human autoimmune trigger, initiates loss of tolerance, rapid progression of autoimmunity, and early onset of glomerulonephritis. We have previously demonstrated that dietary supplementation with the ω-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) suppresses autoimmune pathogenesis and nephritis in this unique model of lupus flaring. In this report, we utilized tissues from prior studies to test the hypothesis that DHA consumption interferes with upregulation of critical genes associated with cSiO₂-triggered murine lupus. A NanoString nCounter platform targeting 770 immune-related genes was used to assess …

Visual Modulation Of Resting State Α Oscillations, Kelly Webster, Tony Ro

Publications and Research

Once thought to simply reflect passive cortical idling, recent studies have demonstrated that α oscillations play a causal role in cognition and perception. However, whether and how cognitive or sensory processes modulate various components of the α rhythm is poorly understood. Sensory input and resting states were manipulated in human subjects while electroencephalography (EEG) activity was recorded in three conditions: eyes-open fixating on a visual stimulus, eyes-open without visual input (darkness), and eyes-closed without visual input (darkness). We show that α power and peak frequency increase when visual input is reduced compared to the eyes open, fixating condition. These results …