Biology Commons^™

Recent Advances In The Juvenile-To-Adult Phase Transition, Yifei Liao, Mingli Xu

Faculty Publications

The transition from the juvenile to adult vegetative phase in Arabidopsis thaliana is a fundamental developmental process that integrates morphological and physiological maturation. Despite extensive study, how vegetative phase change is regulated and how this phase transition is coordinated with plant physiology remain incompletely understood. This review synthesizes recent advances in the molecular regulation and physiological functions of vegetative phase change. We summarize how developmental traits—such as leaf shape, trichome distribution, and margin serration—are controlled through distinct downstream targets of the age-dependent miR156–SPL pathway. We further highlight emerging insights into how epigenetic factors dynamically modify chromatin states of key regulatory …

The Phoenix Flora: Plant Survival, Succession, And Putative Adaptation In The Post-Atomic Landscapes Of Hiroshima And Nagasaki, Gian Marco Ludovici, Paola Amelia Tassi, Alba Iannotti, Colomba Russo, Fausto D'Agostino, Matilde Neble Segade, Timothy Mousseau, Andrea Malizia

Faculty Publications

The atomic bombings of Hiroshima and Nagasaki in 1945 created a unique environment of acute, high-dose ionizing radiation, contrasting sharply with the chronic low-dose rate exposure in the Chernobyl and Fukushima Exclusion Zones. This stands in stark contrast to the chronic, low-dose rate contamination that defines the Chernobyl and Fukushima Exclusion Zones. While the long-term ecological effects of the latter are well-documented, a systematic synthesis of the floral response to the atomic bombings is lacking. This review integrates historical data with modern radio-ecological principles to analyze plant survival and succession. We document the remarkable recovery of vegetation, from the resprouting …

The Phoenix Flora: Plant Survival, Succession, And Putative Adaptation In The Post-Atomic Landscapes Of Hiroshima And Nagasaki, Gian Marco Ludo, Paola Amelia Tassi, Alba Iannotti, Colomba Russo, Fausto D'Agostino, Matilde Neble Segade, Timothy Mousseau, Andrea Malizia

Faculty Publications

The atomic bombings of Hiroshima and Nagasaki in 1945 created a unique environment of acute, high-dose ionizing radiation, contrasting sharply with the chronic low-dose rate exposure in the Chernobyl and Fukushima Exclusion Zones. This stands in stark contrast to the chronic, low-dose rate contamination that defines the Chernobyl and Fukushima Exclusion Zones. While the long-term ecological effects of the latter are well-documented, a systematic synthesis of the floral response to the atomic bombings is lacking. This review integrates historical data with modern radio-ecological principles to analyze plant survival and succession. We document the remarkable recovery of vegetation, from the resprouting …

Coral Larvae Have Unique Transcriptomic Responses To Pathogenic And Probiotic Bacteria, Erin M. Borbee, Isabella V. Changsut, Kira Bernabe, Alicia Schickle, David Nelson, Koty H. Sharp, Lauren E. Fuess

Arts & Sciences Faculty Publications

The growing prevalence of coral disease and other stressors threatens coral reefs, and evidence suggests these stressors not only affect adult corals but may also have impacts on early life stages. Yet, our understanding of coral larval physiology, including immunological function, is significantly limited. Here, we leverage the temperate coral experimental system Astrangia poculata to investigate the transcript-level response of A. poculata to exposure to pathogenic and probiotic bacteria. The bacteria tested in the experiment were the known coral pathogen (Vibrio coralliilyticus RE22) and a probiont (Phaeobacter inhibens S4) previously demonstrated to inhibit the pathogen’s growth. In this study, we …

Evaluating Species At Risk In Data-Limited Fisheries: A Productivity–Susceptibility Analysis For Marine Aquarium Fish, Gabrielle A. Baillargeon, Alice A. Wynn, Jemelyn Grace P. Baldisimo, Michael F. Tlusty, Andrew L. Rhyne

Arts & Sciences Faculty Publications

The marine aquarium trade (MAT) is a significant global industry harvesting millions of wild-caught, live coral reef fishes for public and private aquaria markets in the United States and Europe annually, while supporting fisher livelihoods in the Indo-Pacific. This diverse and species-rich trade is considered data-limited, creating barriers to quantifying the current and future socio-ecological sustainability of the fishery. We present a revised and expanded productivity–susceptibility analysis (PSA) that serves as a holistic risk assessment to estimate the vulnerability of marine aquarium fish to overfishing. Our global analysis includes 306 species that are actively in trade. Improvements to the PSA …

Feeding Mechanics And Digestive Physiology Of Map Turtles, Michael Christopher Fulbright

Doctoral Dissertations

The objective of this research was to relate the form of the map turtle feeding apparatus to its function and digestive physiology. Female map turtles (Genus Graptemys) exhibit pronounced differences in their head shapes and prey bases in the wild. I measured voluntary bite force in megacephalic Pearl River map turtles (G. pearlensis) and microcephalic Sabine map turtles (G. sabinensis) along with a suite of morphological characteristics. I found that many morphological characteristics are good predictors of bite performance in both megacephalic and microcephalic map turtles, and that the commonly used metric of head width noted in other studies of …

Increased Neural Activity In The Bed Nucleus Of The Stria Terminalis Of Uninfected Canaries After Observation Of Infected Conspecifics, Madeleine Chang, Sophia Santangelo, Devon Comito, Bennett Hardy, Patricia C. Lopes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Recent evidence suggests that the immune system may be upregulated in anticipation of pathogen exposure, yet the neural mechanisms that respond to and signal impending infection risk remain poorly understood. We investigated neural responses to infection risk in uninfected hosts observing infected conspecifics, using the canary (Serinus canaria domestica)—Mycoplasma gallisepticum host–parasite system. We focused on five brain regions of interest, comprising three nodes of the social decision-making network—preoptic area, bed nucleus of the stria terminalis (BNST) and hippocampus—a stress modulatory region (paraventricular nucleus) and a visual processing region (nucleus rotundus). After 1 h of observing infected canaries, …

Insects And Arthropods And Their Role In Human Society, Emily Marie Perez-Medina

Whittier Scholars Program

With brightly colored exoskeletons, an excess of both eyes and legs, and seemingly  unpredictable behaviors, insects and arthropods come across as unusual and strange to general audiences. For this reason, they are often classified as “gross,” “ugly,” or “scary,” antagonists  in popular culture. What is not recognized when being represented to the masses is how much human society depends on their presence, and how a world without insects would be a world without most things humans know and love. In order to help reduce the stigma of these tiny, yet mighty creatures, this project serves as a call to action …

Colonization Of Southern Flying Squirrels (Glaucomys Volans) To Urban Nebraska: Range Expansion Or Human Assisted Translocation?, Jennifer Wettschreck, James Wilson, Robert E. Wilson, Abby May, Megan Cary, Jeffrey Huebschman, Sarah A. Sonsthagen

Biology Faculty Publications

Southern flying squirrels (Glaucomys volans; Linnaeus 1758) were first observed in Lincoln, Nebraska, in 2018, 80 km north of their described range. Given that southern flying squirrels are a species of concern within Nebraska, determining the origin of this new population (natural expansion or pet-trade) garnered interest from state biologists. Further, the recent colonization of Lincoln by southern flying squirrels presents a unique opportunity to investigate the genetic implications of a founding event on a small arboreal mammal. The Lincoln population had genetic characteristics suggestive of a single-event colonization with fewer rare alleles and lower genetic diversity than potential …

Bat Species Acoustic Detections And Mist Net Captures 2017, 2018, 2019, 2022, 2023, 2025., Laroy Brandt

Faculty Peer-Reviewed Publications

No abstract provided.

Effect Of Spry Of Potassium Ratio And Cycocel On Physiological Traits Of Maize (Zea Mays L), Asmaa Mohammed Hussein, Eabdallah Yasin Ali

AUIQ Complementary Biological System

The aim of this work was to investigating the effect of foliar application of potassium (K) and the growth regulator Cycocel (CCC) on the physiological traits of maize (Zea mays L). The experiment was designed using a split-plot arrangement within a randomized complete block design (RCBD) with three replicates. The treatments included foliar application of potassium at concentrations of 500, 1000, and 1500 mg.L^–1, as well as three concentrations of the growth regulator Cycocel (0, 150, and 200 mg.L^–1). The results indicated a significant increase in Protein (P), phosphorus, and carbohydrate contents at the concentration of …

Exploring Biogeographical Ancestry Inference Of New York Residents Using A 45 Indel Panel, Amanda Martinez

Student Theses

Biogeographical ancestry (BGA) inference is an important tool in forensic science, providing supplemental information when comparison/reference DNA is not available for traditional DNA analyses. Insertion/deletion polymorphisms (INDELs) have been used in the last decade as ancestry-informative markers (AIMs) for BGA inference because they can be easily adapted to forensic-type samples and are determined using low cost and easy processing methods. Limited research has attempted to estimate ancestry and admixture in United States (U.S.) populations. This study evaluated the effectiveness of a 45- and 21- INDEL panel to measure population admixture proportions of four different origins (African, European, East Asian and …

Chronotropic Response To Intratracheal Versus Intravenous Atropine In Anesthetized Adult Patients: A Randomized Controlled Trial, Ammar H. Mahdi, Majid Alhamaidah, Myasar J. Mohammed, Hussein Ali Hussein, Hussein Alkhfaji

AUIQ Complementary Biological System

Atropine is a commonly used anticholinergic agent in anesthetic practice, administered primarily to counteract bradycardia. Rapid treatment of intraoperative bradycardia is clinically critical, as delays may lead to hemodynamic compromise. This study aimed to compare the onset, magnitude, and duration of the chronotropic response to atropine administered via the intravenous (IV) versus intratracheal (IT) route in anesthetized adult patients. A prospective, single-blind, randomized controlled study was conducted on 60 adult patients classified as American Society of Anesthesiologists (ASA) physical status I-II, scheduled for elective peripheral surgery under general anesthesia. Patients were randomly allocated into three equal groups (n = 20 …

Enhanced No₂ Gas Sensing Using Silver-Doped Cadmium Telluride Nanocrystalline Thin Films, Tunis Balasim Hassan

Karbala International Journal of Modern Science

Nitrogen dioxide (NO₂) is a toxic pollutant that necessitates sensitive and reliable monitoring systems. Conventional gas sensors often lack adequate responsiveness and fast recovery under changing conditions and therefore create a need for semiconductors with enhanced performance, especially at high industrial temperatures (around 250 °C). The study therefore aims to synthesis and evaluate silver-doped cadmium telluride (Ag:CdTe) thin films as NO₂ gas sensors. Pure CdTe and Ag:CdTe with silver concentrations of 5, 10, and 15 wt% were prepared by a co-precipitation process. XRD verified cubic symmetry with a progressive fall in crystallite size (6.67 nm to 5.46 nm at 15 …

The Concept 'Pollination' And Bee Pan-Trap Color And Uv Reflectance Determine The Taxonomic Compositions Of Bee Taxa Captures Across An Elevation Gradient And Seasons In The Jemez Mountains Of New Mexico, Esther A. Burton, Kelly B. Miller, Paul J. Watson, David C. Witherington, Steven Poe, David Lightfoot

Biology ETDs

This thesis examines the pollinator concept and tests how sampling methods shape bee communities. Chapter 1 provides a conceptual and philosophical analysis, arguing that pollination is a process and that pollinators are context-dependent functional roles rather than fixed taxonomic categories. It traces the concept’s development from natural history to ecological theory, introduces a dual-goal model separating plant reproduction from visitor foraging, and proposes a classification framework based on evidentiary certainty and pollination potential to resolve ambiguity in pollination research.

Chapter 2 applies these ideas empirically by evaluating how pan-trap color and ultraviolet (UV) reflectance influence bee assemblages across elevation and …

From Cranes To Clinics: Genomic Epidemiology At The Human-Animal Interface, Sarah Shrum

Biology ETDs

Emerging infectious diseases represent a significant, increasing threat to human life, economic stability, and global security. The One Health framework, which promotes human health and wellness through the understanding that animal, environmental, and human health are interwoven, is critical to understanding pathogen emergence and transmission. This is underscored by the fact that roughly 60% of all human pathogens and 75% of emerging infectious disease are zoonotic, meaning they are transmitted from animals to humans.

The work presented in this dissertation integrates genomic epidemiology, ecological analysis, and One Health Surveillance approaches to characterize cross-species circulation of opportunistic yeast pathogens (Candida …

Characterizing A Potential Cbp/P300 Histone Acetyltransferase Homolog In Tardigrade Germline Specification And Development, Brittney Michelle Hartshorn

Honors Projects

Germline specification is a fundamental process that ensures the proper development of germ cells. Germline specification occurs either through germ cell determinants maternally inherited through the mechanism of preformation or through induction, where cell interaction and epigenetic modifications direct specification. Determining how these mechanisms evolved and diverged remains an important question in developmental biology. Despite research on germline regulation in model organisms such as Caenorhabditis elegans or Drosophila melanogaster, such regulation remains poorly understood in many other animal groups. Tardigrades are an emerging model system for investigating developmental mechanisms due to their phylogenetic placement and experimentally tractable embryos. CBP/P300 is …

Investigating Changes In The Stable Isotopic Composition Of Juniperus Osteosperma Over 34,000 Years Of Climatic Shifts, Lisa S. Garcia

Biology ETDs

Isotopic compositions of plants from the past provides empirical evidence for paleoclimatic shifts and plants physiologically response. This study used Neotoma paleomiddens (fossilized debris piles) collected from Death Valley National Park, which contained preserved abundant plant materials. These middens range from modern to >35,000 years and capture different climatic events in Earth history. Employing Juniperus osteosperma (Utah Juniper) leaves found in middens, I investigated variation in carbon and nitrogen stable isotopic composition. To help interpret paleomidden results, we used modern field and herbaria samples of Juniperus from a spatial gradient stretching across their geographic range. Results showed δ ¹³C …

Reassembling Riparian Ecosystems: Stream Restoration Effects On Vegetation, Arthropods, And Aquatic-Terrestrial Connectivity, Katelyn P. Driscoll

Biology ETDs

Riparian areas exist at the aquatic-terrestrial interface and provide disproportionate ecosystem services, yet multiple stressors have degraded these zones globally. Stream restoration seeks to reverse degradation, but rigorous evaluation of treatment effectiveness remains limited. I conducted a before-after-control-impact (BACI) study in the southern Rocky Mountains to evaluate two stream restoration treatments—beaver dam analogs (BDAs) and plug-and-ponds (P&Ps)—across three dimensions of riparian ecosystem response. Using Bayesian analysis, I quantified treatment effects on functional diversity and composition of riparian plant communities. Using generalized linear mixed models, I evaluated restoration effects on riparian arthropod abundance, richness and guild composition across lateral gradients and …

Patterns Of Molecular Evolution Driving Reproductive And Genomic Processes In Sauropsids, Taylor Green

Theses and Dissertations

Sexual reproduction is an important driver of genetic diversity and speciation through such forces as selection, mutation, and drift. Sauropsids are an appropriate clade to study shared molecular drivers of sexual and genomic evolution due to their genome architecture, sex determination mechanism (SDM) plasticity, and large syntenous genomic regions. Using comparative phylogenetic methods, I identify predictable patterns of selection in meiotic recombination genes and clade-specific drivers of recombination rate evolution. Then, leveraging whole genome sequencing, I demonstrate that American alligator genomes are characterized by an ancient loss of genetic diversity driven by drift and historic inbreeding. I also generate a …

Reproductive Genetics Of Caenorhabditis Nematodes, Dharani U. Matharage

Theses and Dissertations

Variation in reproductive traits and genome evolution reflects the interaction between selection, environment, and life-history. In the genus Caenorhabditis, recombination rate and sperm size exhibit a striking variation between strains and species. Here, Iintegrate three projects investigating recombination rate variation and recombination plasticity in C. elegans and sperm size divergence across Caenorhabditis species. First, I quantify recombination rates in two genetically distinct strains, N2 and CB4856, with different levels of laboratory adaptation using fluorescent markers spanning across gene-rich and gene-poor regions of the chromosome IV. I identify significant differences in recombination rate between the two strains within both gene-rich and …

Increasing Evolution Acceptance Among Religious Adults Through Targeted Education, Jamie Jensen

ScholarsArchive Data

These data come from a study measuring the effectiveness of the Shareable Home Application for Reconciling Evolution (SHARE) tool, which consists of five short videos addressing the nature of science, compatibility between doctrine of the Church of Jesus Christ of Latter-day Saints and evolution, evolutionary mechanisms, and evidence for evolution, including human evolution.

From Miocene Origins To Ecological Diversification: Unraveling Evolutionary Dynamics Of North American Asters (Symphyotrichum), Sushil Dahal

Theses and Dissertations

Symphyotrichum, a plant genus traditionally treated within the genus Aster L., comprises >100 species of annual or perennial plants in the Compositae family Asteraceae. One of the most diverse genera in the southeastern US flora, the genus extends across the Americas, the Caribbean as well as eastern Eurasia. Despite its presence across the major American biomes and with distinctive floristic characteristics, several question regarding Symphyotrichum remains obscure. This research project focuses on exploring diverse aspects of Symphyotrichum systematics, biogeography and evolution. I tested three main hypotheses: (1a) Symphyotrichum originated ancestrally across Mexico and eastern North America in the Miocene ( …

Assessing Biotic And Abiotic Drivers Of Hybridization And Species Delimitation In A Highly Reticulate Syngameon, Nicholas John Engle-Wrye

Theses and Dissertations

Hybridization, or the flow of genetic materials between varieties or species, shapes evolution by generating novel genotypes, altering allele frequencies, and driving diversification. Yet, the rate at which hybridization occurs is heterogeneous across the tree of life and the ecological and evolutionary factors that govern its occurrence remain poorly understood. This dissertation examines how conserved biotic and abiotic niches influence hybridization and uses integrative methods to delimit species boundaries within Heuchera (Saxifragaceae), a genus notable for widespread interspecific gene flow and cryptic morphological diversity. Results reveal that hybridization is most frequent where pre- and postzygotic barriers are weak, as with …

Cortical Bone Density And Thickness Assessment Of Intraradicular Sites In Adolescent Patients Using Cbct Imaging, Sara Endo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Background: The indications for the use of cone beam computed tomography (CBCT) in orthodontics has grown since it was first introduced and dentists are discovering new ways that 3D images enhance diagnosis and treatment planning. Evaluating bone quality and quantity can be measured as bone density and thickness in CBCT imaging and is helpful for temporary anchorage device (TAD) placement in orthodontic treatment. TADs rely on primary stability and are commonly used in orthodontic treatment to increase anchorage and expand the limit that nonsurgical orthodontics can provide.

Objectives: This study aims to assess the bone thickness and density at different …

A Tale Of Two Mammals: Tenrec Ecaudatus And Homo Sapiens, Debra Renee Kerr

UNLV Theses, Dissertations, Professional Papers, and Capstones

Most modern mammals maintain stable body temperatures (Tb) ~37ºC and high metabolic rates. Hibernators, like ground squirrels, are homeothermic during the active summer season, but are heterothermic during the hibernation season. During the hibernation season, ground squirrels follow a predictable pattern of torpor bouts interrupted by interbout arousals. Tenrecs are unusual because they are heterothermic and heterometabolic even during the active season. Previously, ground squirrel bile constituents were shown to be predictive of whether a squirrel is in the summer active or winter hibernation season. We found tenrec bile constituents were highly variable and not predictive of seasonal and metabolic …

Thermal Physiological Ecology Of The Relict Leopard Frog At Hot And Cold Springs, Robert P. Pelletier Iii

UNLV Theses, Dissertations, Professional Papers, and Capstones

The relict leopard frog (Rana onca) once ranged across drainages in southern Nevada, northwestern Arizona, and southwestern Utah. Following a decline, the species only persisted in a few geothermally influenced hot springs, which led to the perspective that hot springs were high-quality habitat. Rana onca has been under intensive, multiagency management and the species has been translocated to establish additional populations, including at cold-water sites. Three research studies are presented into the thermal physiological ecology of R. onca with the aim of informing conservation strategy. The research was focused at a thermally influenced hot spring and a cold-water spring to …

Junctional Actin As A Mechanical Hub For Supracellular Actomyosin Force Transmission During Apical Constriction, Jasneet Brar

UNLV Theses, Dissertations, Professional Papers, and Capstones

Apical constriction is a conserved morphogenetic mechanism that drives epithelial folding during development. During ventral furrow formation in Drosophila melanogaster, contractile actomyosin networks generate forces that reduce apical cell area resulting in tissue invagination. For these cell-scale forces to produce coordinated tissue-scale changes, contractile networks must be mechanically integrated across neighboring cells. Although adherens junctions are known to mediate this coupling, it is unclear how junctions are integrated into cortical actin cytoskeleton, which directly determines cell, and consequently tissue, shape. This thesis tests the hypothesis that supracellular actomyosin organization during apical constriction depends on distinct adherens junction based mechanical couplings: …

The Competition Between Splicing And 3′ Processing Shapes The Human Transcriptome, Lindsey V. Soles, Shuangyu Li, Liang Liu, Kristianna S.K. Sarkan, Erik G. Alvstad, Lusong Tian, Yoseop Yoon, Marielle Valdez, Ivan Marazzi, Yongsheng Shi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Eukaryotic pre-mRNA processing steps, including splicing and 3′ processing, are tightly coordinated, yet the underlying mechanisms remain incompletely understood. U1 snRNP has been proposed to inhibit 3′ processing at intronic polyadenylation (IPA) sites through a splicing-independent mechanism termed telescripting. In contrast, we discovered that disrupting splicing by using six different methods—targeting various key components such as U1 snRNP, U2 snRNP, U2AF, and SF3b—activates 3′ processing at thousands of IPA sites. Notably, splicing inhibition, especially of U1 snRNP, induced widespread premature transcription termination within gene bodies through both IPA-coupled and IPA-independent mechanisms. Inhibition of different splicing factors activated overlapping and distinct …

First Recombinant Expression, Purification, And Film Formation Of A Single Solitary Bee Silk Protein From Osmia Lignaria, Oran Wasserman, Kristin K. Durrant, Jackson J. Morley, Paula E. Oliveira, Mallory R. Wootton, Brianne E. Bell, Ethon D. Van Noy, Randolph V. Lewis, Justin A. Jones

Biology Student Research

Solitary bees account for most described bee species worldwide, with many spinning silk fibers to form protective cocoons during development; however, solitary bee silk proteins remain largely unexplored in recombinant systems and biomaterial fabrication. Here, we report the first recombinant expression and biomaterial formation from a solitary bee silk protein. Osmia lignaria silk fibroin 2 (OligF2) was expressed in Escherichia coli BL21(DE3) using an expression and purification scheme adapted from a recombinant hagfish intermediate filament (rHIF) workflow, yielding 0.34 g/L at ~70% purity. The purified OligF2 protein was cast into films at 0.75% and 1% (w/v). …