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Full-Text Articles in Life Sciences

Metabolism Underlies Physiological Homeostasis In Drosophila, Omera B. Matoo, Cole R. Julick, Kristi Montooth Jun 2019

Metabolism Underlies Physiological Homeostasis In Drosophila, Omera B. Matoo, Cole R. Julick, Kristi Montooth

Faculty Publications in the Biological Sciences

Organismal physiology emerges from metabolic pathways and subcellular structures like the mitochondria that can vary across development and among individuals. Here, we tested whether genetic variation at one level of physiology can be buffered at higher levels of biological organization during development by the inherent capacity for homeostasis in physiological systems. We found that the fundamental scaling relationship between mass and metabolic rate, as well as the oxidative capacity per mitochondria, changed significantly across development in the fruit fly Drosophila. However, mitochondrial respiration rate was maintained at similar levels across development. Furthermore, larvae clustered into two types—those that switched ...


Life History Traits And Functional Processes Generate Multiple Pathways To Ecological Stability, John P. Delong, Torrance C. Hanley, Jean P. Gibert, Linda M. Puth, David M. Post Apr 2019

Life History Traits And Functional Processes Generate Multiple Pathways To Ecological Stability, John P. Delong, Torrance C. Hanley, Jean P. Gibert, Linda M. Puth, David M. Post

Faculty Publications in the Biological Sciences

Stability contributes to the persistence of ecological communities, yet the interactions among different stabilizing forces are poorly understood. We assembled mesocosms with an algal resource and one to eight different clones of the consumer Daphnia ambigua and tracked algal and Daphnia abundances through time. We then fitted coupled ordinary differential equations (ODEs) to the consumer–resource time series. We show that variation in different components of stability (local stability and the magnitude of population fluctuations) across mesocosms arises through variation in life history traits and the functional processes represented by ODE model parameters. Local stability was enhanced by increased algal ...


Morphological Changes In American Kestrels (Falco Sparverius) At Continental Migration Sites, Teresa E. Ely, Christopher W. Briggs, Shawn E. Hawks, Gregory S. Kaltenecker, David L. Evans, Frank J. Nicoletti, Jean-François Therrien, Olin Allen, John Delong Apr 2019

Morphological Changes In American Kestrels (Falco Sparverius) At Continental Migration Sites, Teresa E. Ely, Christopher W. Briggs, Shawn E. Hawks, Gregory S. Kaltenecker, David L. Evans, Frank J. Nicoletti, Jean-François Therrien, Olin Allen, John Delong

Faculty Publications in the Biological Sciences

Many American kestrel (Falco sparverius) populations are declining across North America. Potential causes include mortality from reduction in food availability, a changing climate, habitat degradation, an increase in avian predators, disease, and toxins. We analyzed American kestrel count and banding data from seven raptor migration sites throughout North America with at least 20 years of migration data. We used count data to determine the year at which the kestrel population began a significant decline and then used banding records to determine whether body mass and wing chord declined after this point. We found reductions in kestrel body mass at three ...


Detection Of Heteroplasmic Single Nucleotide Polymorphisms Using Melt Curve Analysis And Dual Labeled Fluorescent Probes, Emily Jezewski Apr 2019

Detection Of Heteroplasmic Single Nucleotide Polymorphisms Using Melt Curve Analysis And Dual Labeled Fluorescent Probes, Emily Jezewski

Honors Theses, University of Nebraska-Lincoln

Plant mitochondrial genomes are strange – they are unusually large, consist of huge amounts of non-coding DNA, and contain of several overlapping regions throughout the genome. The genome is made of several different sized linear and circular molecules and different mitochondria within a cell will have different pieces of the genome. Even if multiple mitochondria contain the same region of the genome, these sequences can differ by single nucleotide polymorphisms (SNPS). This is known as heteroplasmy. Heteroplasmy has been documented in Arabidopsis thaliana using whole-genome sequencing data. While heteroplasmy is well-documented, its existence in the mitochondrial genome is unexpected and it ...


Putting The I In Science, Naomi Kirkvold Apr 2019

Putting The I In Science, Naomi Kirkvold

Honors Expanded Learning Clubs

This club gets kids interested in science in ways that they may not have experienced in a classroom by doing weekly experiments.


Establishing Enhanced Learning Outcomes In Science For First Generational Undergraduate College Students, Marianna Burks Apr 2019

Establishing Enhanced Learning Outcomes In Science For First Generational Undergraduate College Students, Marianna Burks

Theses, Student Research, and Creative Activity: Department of Teaching, Learning and Teacher Education

First-generation students represent an increasing percentage of the demographic for college and university enrollment at both the undergraduate and graduate levels. Since 2001, results from the National Center for Education Statistics Longitudinal Study, indicates ‘higher percentages of first-generations college students attended public postsecondary institutions-76 vs. 72%’ (Redford & Hoyer, 2017). There is insufficient research, however, concerning how first-generation students’ needs are different, even unique, from those students who are second- generation and beyond attending college (National Center for Educational Statistics, 2017). Since this increase of students enrolling in post-secondary education, ‘understanding the needs of first-generation students is imperative more now than ...


The Ecological Niche Of Echinococcus Multilocularis In North America: Understanding Biotic And Abiotic Determinants Of Parasite Distribution With New Records In New Mexico And Maryland, United States, Sebastian Botero-Cañola, Altangerel Tsogtsaikhan Dursahinhan, Sara E. Rácz, Parker V. Lowe, John E. Ubelaker, Scott Lyell Gardner Apr 2019

The Ecological Niche Of Echinococcus Multilocularis In North America: Understanding Biotic And Abiotic Determinants Of Parasite Distribution With New Records In New Mexico And Maryland, United States, Sebastian Botero-Cañola, Altangerel Tsogtsaikhan Dursahinhan, Sara E. Rácz, Parker V. Lowe, John E. Ubelaker, Scott Lyell Gardner

Scott Gardner Publications & Papers

English abstract: Understanding the factors shaping the niche of parasites and its expression over geographical space and through time continues to be a modern scientific challenge with the results of research in this area directly influencing both theoretical and applied biology. This is especially important for proactive management of zoonotic parasites such as Echinococcus multilocularis, the etiologic agent of alveolar echinococcosis. Echinococcus multilocularis has a Holarctic distribution; with its geographic range and prevalence increasing recently in areas of the western Palearctic, while its distribution dynamics are poorly understood in the Nearctic. In this paper, we use an ecological niche modeling ...


Plant Mitochondrial Genome Evolution And Structure Has Been Shaped By Double-Strand Break Repair And Recombination, Emily Wynn Apr 2019

Plant Mitochondrial Genome Evolution And Structure Has Been Shaped By Double-Strand Break Repair And Recombination, Emily Wynn

Dissertations and Theses in Biological Sciences

Plant mitochondrial genomes are large but contain a small number of genes. These genes have very low mutation rates, but genomes rearrange and expand at significant rates. We propose that much of the apparent complexity of plant mitochondrial genomes can be explained by the interactions of double-strand break repair, recombination, and selection. One possible explanation for the disparity between the low mutation rates of genes and the high divergence of non-genes is that synonymous mutations in genes are not truly neutral. In some species, rps14 has been duplicated in the nucleus, allowing the mitochondrial copy to become a pseudogene. By ...


Regulation Of Vaccinia Virus Replication: A Story Of Viral Mimicry And A Novel Antagonistic Relationship Between Vaccinia Kinase And Pseudokinase, Annabel T. Olson Apr 2019

Regulation Of Vaccinia Virus Replication: A Story Of Viral Mimicry And A Novel Antagonistic Relationship Between Vaccinia Kinase And Pseudokinase, Annabel T. Olson

Dissertations and Theses in Biological Sciences

Poxviruses employ sophisticated signaling pathways that thwart cellular defense mechanisms and simultaneously ensure viral factors are modulated properly. Yet, our understanding of these complex signaling networks are incomplete. For example, the vaccinia B1 kinase plays a vital role in inactivating the cellular antiviral factor BAF, and is suggested to orchestrate other pathways. B1 is highly conserved among poxviruses and exhibits a remarkable degree of similarity to VRKs, a family of cellular kinases, suggesting that the viral enzyme has evolved to mimic VRK activity. Indeed, B1 and VRKs have been demonstrated to target a shared substrate, the DNA binding protein BAF ...


Status Of The Plains Harvest Mouse (Reithrodontomys Montanus Griseus) In Eastern Nebraska, Keith Geluso, Greg D. Wright Mar 2019

Status Of The Plains Harvest Mouse (Reithrodontomys Montanus Griseus) In Eastern Nebraska, Keith Geluso, Greg D. Wright

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

In eastern Nebraska, current status of the Plains Harvest Mouse (Reithrodontomys montanus griseus) is not well understood. Infrequent captures during the last century have led to a paucity of information regarding this taxon, and some researchers postulate that its distribution has contracted in the state. In 2008, we conducted a field survey for R. m. griseus in eastern Nebraska, amassed prior specimen records, and examined most of the specimens for this subspecies from the state to better understand its distribution, natural history, and subspecific status. In our field efforts, we only captured a single individual despite > 8,000 trap nights ...


Enzyme Kinetics Of Dutpase From The Planarian Dugesia Ryukyuensis, Shahanoor Alam, Hideaki Moriyama Mar 2019

Enzyme Kinetics Of Dutpase From The Planarian Dugesia Ryukyuensis, Shahanoor Alam, Hideaki Moriyama

Faculty Publications in the Biological Sciences

Objective: Planarians including Dugesia ryukyuensis (Dr) have strong regenerative abilities that require enhanced DNA replication. Knockdown of the DUT gene in Dr, which encodes deoxyuridine 5′-triphosphate pyrophosphatase (dUTPase), promotes DNA fragmentation, inhibits regeneration, and eventually leads to death. dUTPase catalyzes the hydrolysis of dUTP to dUMP and pyrophosphate. dUTPase is known to prevent uracil misincorporation in DNA by balancing the intracellular ratio between dUTP and dTTP, and contributes to genome stability. Nevertheless, the catalytic performance of Dr-dUTPase has not been reported.

Results: To confirm the catalytic activity of Dr-dUTPase, we cloned and expressed Dr-DUT in E. coli. Then, we ...


Microbial Community Of Saline, Alkaline Lakes In The Nebraska Sandhills Based On 16s Rrna Gene Amplicon Sequence Data, Nicole A. Fiore, David D. Dunigan Ph. D., Julie J. Shaffer, Ryan Roberts, Sanjay Antony-Babu, Bradley A. Plantz, Kenneth W. Nickerson, Andrew K. Benson, Karrie A. Weber Mar 2019

Microbial Community Of Saline, Alkaline Lakes In The Nebraska Sandhills Based On 16s Rrna Gene Amplicon Sequence Data, Nicole A. Fiore, David D. Dunigan Ph. D., Julie J. Shaffer, Ryan Roberts, Sanjay Antony-Babu, Bradley A. Plantz, Kenneth W. Nickerson, Andrew K. Benson, Karrie A. Weber

Faculty Publications in the Biological Sciences

The Nebraska Sandhills region contains over 1,500 geochemically diverse interdunal lakes, some of which are potassium rich, alkaline, and hypersaline. Here, we report 16S rRNA amplicon pyrosequencing data on the water and sediment microbial communities of eight alkaline lakes in the Sandhills of western Nebraska.


H/L Ratio As A Measurement Of Immune Function In Terrapene Ornata Species, Vesa Govori Mar 2019

H/L Ratio As A Measurement Of Immune Function In Terrapene Ornata Species, Vesa Govori

Honors Theses, University of Nebraska-Lincoln

White blood cells are a key part of the immune system, and changes in white cell count can reveal the overall state of health and the immune systems functional ability of a species. White blood such as heterophils and lymphocytes are essential for being able to fight off infections. Analyzing different cell ratios has been commonly done before as a way to observe immune function in bird species as well as other species. Understanding that there are different functions between the different white blood cells provides an extra interesting perspective to what could be happening in the immune system function ...


Escaping Death: Naloxone's Chemical Nature And Potential To Combat The Opioid Epidemic, Abigale Miller Mar 2019

Escaping Death: Naloxone's Chemical Nature And Potential To Combat The Opioid Epidemic, Abigale Miller

Honors Theses, University of Nebraska-Lincoln

Naloxone is a life-saving drug with the ability to reverse an opioid overdose. As the opioid epidemic’s death toll rises, we can turn to Naloxone as a tool to combat the crisis. The epidemic, born of corruption, has a wide reach among the people of the United States, with especially firm grasps on middle-aged people, sufferers of chronic pain, white Americans and those living in the eastern portion of the country. Naloxone’s elegant design saves lives by effectively competing for a position on an opioid biding receptor in the brain to almost instantly end an overdose and restore ...


Student Perceptions Of Reasons For Lecture And Active Learning, Calan Koch Mar 2019

Student Perceptions Of Reasons For Lecture And Active Learning, Calan Koch

Honors Theses, University of Nebraska-Lincoln

With perceived student resistance to active learning in the classroom, instructors are hesitant to implement such methods into their classroom structure despite how effective they may be. This research seeks to understand student perceptions related to the transition to higher prevalence of active learning techniques. We aimed to find answers to how students perceive the ideal classroom to be structured, what reasons they perceive for lecture and active learning components, and possible explanations to concerns of groupwork during class time. We analyzed 64 interviews with undergraduate biology students at the University of Nebraska- Lincoln, developed coding rubrics from commonly found ...


The Nature Of Science As A Foundation For Fostering A Better Understanding Of Evolution, Craig E. Nelson, Lawrence C. Scharmann, Jean Beard, Lawrence I. Flammer Feb 2019

The Nature Of Science As A Foundation For Fostering A Better Understanding Of Evolution, Craig E. Nelson, Lawrence C. Scharmann, Jean Beard, Lawrence I. Flammer

Faculty Publications: Department of Teaching, Learning and Teacher Education

Misunderstandings of the nature of science (NOS) contribute greatly to resistance to evolutionary theory especially among non-scientific audiences. Here we delineate three extended instructional examples that make extensive use of NOS to establish a foundation upon which to more successfully introduce evolution. Specifically, these instructional examples enable students to consider evolutionary biology using NOS as a lens for interpretation of evolutionary concepts. We have further found, through our respective research efforts and instructional experiences, that a deep understanding of NOS helps students understand and accept the scientific validity of evolution and, conversely, that evolution provides an especially effective context for ...


Persistent Viral Reservoirs In Lymphoid Tissues In Siv-Infected Rhesus Macaques Of Chinese-Origin On Suppressive Antiretroviral Therapy, Summer Siddiqui, Stefanie Perez, Yong Gao, Lara Doyle-Meyers, Brian T. Foley, Qingsheng Li, Binhua Ling Jan 2019

Persistent Viral Reservoirs In Lymphoid Tissues In Siv-Infected Rhesus Macaques Of Chinese-Origin On Suppressive Antiretroviral Therapy, Summer Siddiqui, Stefanie Perez, Yong Gao, Lara Doyle-Meyers, Brian T. Foley, Qingsheng Li, Binhua Ling

Faculty Publications in the Biological Sciences

Understanding HIV latent reservoirs in tissues is essential for the development of new strategies targeting these sites for eradication. Here, we assessed the size of latent reservoirs and the source of residual viruses in multiple lymphoid tissues of SIV-infected and fully suppressed rhesus macaques of Chinese-origin (cRMs). Eight cRMs were infected with SIVmac251 and treated with tenofovir and emtricitabine daily for 24 weeks initiated 4 weeks post-infection. Four of the eight animals reached sustained full viral suppression with undetectable viremia. The levels of cell-associated SIV DNA varied in peripheral blood mononuclear cells (PBMCs) and multiple lymphoid tissues, but with higher ...


Can Vegfc Form Turing Patterns In The Zebrafish Embyro?, Kenneth Y. Wertheim, Tina Roose Jan 2019

Can Vegfc Form Turing Patterns In The Zebrafish Embyro?, Kenneth Y. Wertheim, Tina Roose

Faculty Publications in the Biological Sciences

This paper is concerned with a late stage of lymphangiogenesis in the trunk of the zebrafish embryo. At 48 hours pos-fertilisation (HPF), a pool of parachordal lymphangioblasts (PLs) lies in the horizontal myoseptum. Between 48 and 168 HPF, the PLs spread from the horizontal myoseptum to form the throacic duct, dorsal longitudinal lymphatic vessel, and parachordal lymphatic vessel. This paper deals wit hthe potential of vascular endothelial growth factor C (VEGFC) to guide the differentiation of PLs into the mature lymphatic endothelial cells that form the vessels. We built a mathematical model to describe the biochemical interactions between VEGFC, collagen ...


Radiomic Feature Stability Across 4d Respiratory Phases And Its Impact On Lung Tumor Prognosis Prediction, Qian Du, Michael Baine, Kyle Bavitz, Josiah Mcallister, Xiaoying Liang, Hongfeng Yu, Jeffrey Ryckman, Lina Yu, Hengle Jiang, Sumin Zhou, Sumin Zhou, Chi Zhang, Dandan Zheng Jan 2019

Radiomic Feature Stability Across 4d Respiratory Phases And Its Impact On Lung Tumor Prognosis Prediction, Qian Du, Michael Baine, Kyle Bavitz, Josiah Mcallister, Xiaoying Liang, Hongfeng Yu, Jeffrey Ryckman, Lina Yu, Hengle Jiang, Sumin Zhou, Sumin Zhou, Chi Zhang, Dandan Zheng

Faculty Publications in the Biological Sciences

Radiomic analysis has recently demonstrated versatile uses in improving diagnostic and prognostic prediction accuracy for lung cancer. However, since lung tumors are subject to substantial motion due to respiration, the stability of radiomic features over the respiratory cycle of the patient needs to be investigated to better evaluate the robustness of the interpatient feature variability for clinical applications, and its impact in such applications needs to be assessed. A full panel of 841 radiomic features, including tumor intensity, shape, texture, and wavelet features, were extracted from individual phases of a four-dimensional (4D) computed tomography on 20 early-stage non-small-cell lung cancer ...


Ecological Pleiotropy And Indirect Effects Alter The Potential For Evolutionary Rescue, John P. Delong, Jonathan Belmaker Jan 2019

Ecological Pleiotropy And Indirect Effects Alter The Potential For Evolutionary Rescue, John P. Delong, Jonathan Belmaker

Faculty Publications in the Biological Sciences

Invading predators can negatively affect naïve prey populations due to a lack of evolved defenses. Many species therefore may be at risk of extinction due to overexploitation by exotic predators. Yet the strong selective effect of predation might drive evolution of imperiled prey toward more resistant forms, potentially allowing the prey to persist. We evaluated the potential for evolutionary rescue in an imperiled prey using Gillespie eco‐evolutionary models (GEMs). We focused on a system parameterized for protists where changes in prey body size may influence intrinsic rate of population growth, space clearance rate (initial slope of the functional response ...