Open Access. Powered by Scholars. Published by Universities.®

Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

29,276 Full-Text Articles 54,566 Authors 4,937,802 Downloads 335 Institutions

All Articles in Biology

Faceted Search

29,276 full-text articles. Page 1 of 974.

Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella 2022 University of New Mexico

Mixing It Up: The Impact Of Episodic Introgression On The Evolution Of High-Latitude Mesocarnivores, Jocelyn P. Colella

Biology ETDs

At high latitudes, climatic oscillations have triggered repeated episodes of organismal divergence by geographically isolating populations. For terrestrial species, extended isolation in glacial refugia – ice-free regions that enable terrestrial species persistence through glacial maxima – is hypothesized to stimulate allopatric divergence. Alternatively, upon glacial recession, divergent populations expanded from independent glacial refugia and often contacted other diverging populations. In the absence of reproductive isolating mechanisms, this biogeographic process may trigger hybridization and ultimately, gene flow between divergent taxa. My dissertation research aims to understand how these episodic periods of isolation and contact have impacted the evolution of high latitude species. To ...


Restoring Polyhyrdoxybutyrate (Phb) Depolymerase Expression In A Bald Mutant Of Streptomyces Sp. Sfb5a, Youmna Moawad 2021 Bridgewater College

Restoring Polyhyrdoxybutyrate (Phb) Depolymerase Expression In A Bald Mutant Of Streptomyces Sp. Sfb5a, Youmna Moawad

Honors Projects

Polyhydroxybutyrate (PHB) is a biodegradable, plastic-like polymer produced by some bacteria and degraded by others. The filamentous bacterium Streptomyces sp. SFB5A degrades PHB for growth using an extracellular PHB depolymerase, encoded by the phaZ gene. A morphological mutant of this bacterium, bld4, cannot form aerial filaments and cannot produce PHB depolymerase, despite having the phaZ gene. The inability to synthesize PHB depolymerase may be due to a mutation in a gene encoding one of its transcriptional regulators. A gene (lrp) coding for a potential transcriptional regulator is located 2,700 base pairs upstream from phaZ. Our goal was to clone ...


Local Environmental Variables Are Key Drivers Of Ant Taxonomic And Functional Beta-Diversity In A Mediterranean Dryland, Clara Frasconi Wendt, Ana Ceia-Hasse, Alice Nunes, Robin Verble, Giacomo Santini, Mário Boieiro, Cristina Branquinho 2021 Missouri University of Science and Technology

Local Environmental Variables Are Key Drivers Of Ant Taxonomic And Functional Beta-Diversity In A Mediterranean Dryland, Clara Frasconi Wendt, Ana Ceia-Hasse, Alice Nunes, Robin Verble, Giacomo Santini, Mário Boieiro, Cristina Branquinho

Biological Sciences Faculty Research & Creative Works

The decomposition of beta-diversity (β-diversity) into its replacement (βrepl) and richness (βrich) components in combination with a taxonomic and functional approach, may help to identify processes driving community composition along environmental gradients. We aimed to understand which abiotic and spatial variables influence ant β-diversity and identify which processes may drive ant β-diversity patterns in Mediterranean drylands by measuring the percentage of variation in ant taxonomic and functional β-diversity explained by local environmental, regional climatic and spatial variables. We found that taxonomic and functional replacement (βrepl) primarily drove patterns in overall β-diversity (βtot). Variation partitioning analysis showed ...


Physiological Processes, Chirag B. Raval 2021 CUNY City College

Physiological Processes, Chirag B. Raval

Open Educational Resources

Physiological Processes is designed to introduce fundamental concepts of physiology to biomedical engineering learners. Areas covered include: neural, muscular, cardiovascular, respiratory and renal system function; bioelectrical signals, capillary-level transport, organ-level exchange. Whenever possible, analysis will be quantitative in order to fulfill the course goals and to build the foundation for the subsequent biomedical engineering curriculum. This course is for Biomedical Engineering majors only.


The Periaqueductal Grey In Opioid Tolerance And Chronic Pain, Akila Ram 2021 Utah State University

The Periaqueductal Grey In Opioid Tolerance And Chronic Pain, Akila Ram

All Graduate Theses and Dissertations

Pain is the body’s natural warning system to indicate one is in an environment highly detrimental to survival. The body’s response to the sensation of pain is to immediately withdraw from this environment, ensuring continued survival. However, when pain lasts beyond the window in which it is useful, it no longer serves as a helpful warning system but instead degrades the quality of life. Chronic pain leads to patients seeking opioids to alleviate their condition and regain control of their lives. A severe negative side effect of the use of opioids to treat chronic pain is the development ...


Investigation Into The Evolution Of Heterogeneity Within Secondary Replicons And Their Maintenance In Genus Variovorax, Christopher Ne Ville 2021 California State University - San Bernardino

Investigation Into The Evolution Of Heterogeneity Within Secondary Replicons And Their Maintenance In Genus Variovorax, Christopher Ne Ville

Electronic Theses, Projects, and Dissertations

Approximately 10% of all bacterial genomes sequenced thus far contain a secondary replicon. This considerable genetic reservoir contains many potentially mobilizable elements, allowing for the formation of many unique secondary replicons. This property of bacterial populations vastly increases the genomic diversity available to species that effectively take up and maintain these replicons. Members of the genus Variovorax have extensive heterogeneity in genome architecture, including sequenced isolates containing plasmids, megaplasmids, and chromids. Using available Illumina data on the NCBI database, we have completed these assemblies using 3rd generation sequencing methods on 17 members of this genus. We have sequenced, assembled ...


Characteristics Of Non-Fatal Attacks By Black Bears: Conterminous United States, 2000–2017, Janel M. Scharhag, Cady Sartini, Shawn M. Crimmins, Scott E. Hygnstrom, Jeffrey B. Stetz 2021 University of Wisconsin-Stevens Point

Characteristics Of Non-Fatal Attacks By Black Bears: Conterminous United States, 2000–2017, Janel M. Scharhag, Cady Sartini, Shawn M. Crimmins, Scott E. Hygnstrom, Jeffrey B. Stetz

Human–Wildlife Interactions

Attacks on humans by bears (Ursus spp.) have increased in recent decades, as both human and bear populations have increased. To help mitigate the risk of future attacks, it is important to understand the circumstances in past attacks. Information and analyses exist regarding fatal attacks by both American black bears (Ursus americanus) and brown bears (U. arctos) as well as non-fatal attacks by brown bears. No similarly thorough analyses on non-fatal attacks by black bears are available. Our study addressed this information gap by analyzing all (n = 210) agency-confirmed, non-fatal attacks by black bears in the 48 conterminous United States ...


Zebrafish Blunt-Force Tbi Induces Heterogenous Injury Pathologies That Mimic Human Tbi And Responds With Sonic Hedgehog-Dependent Cell Proliferation Across The Neuroaxis, James Hentig, Kaylee Cloghessy, Manuela Lahne, Yoo Jin Jung, Rebecca A. Petersen, Ann C. Morris, David R. Hyde 2021 University of Notre Dame

Zebrafish Blunt-Force Tbi Induces Heterogenous Injury Pathologies That Mimic Human Tbi And Responds With Sonic Hedgehog-Dependent Cell Proliferation Across The Neuroaxis, James Hentig, Kaylee Cloghessy, Manuela Lahne, Yoo Jin Jung, Rebecca A. Petersen, Ann C. Morris, David R. Hyde

Biology Faculty Publications

Blunt-force traumatic brain injury (TBI) affects an increasing number of people worldwide as the range of injury severity and heterogeneity of injury pathologies have been recognized. Most current damage models utilize non-regenerative organisms, less common TBI mechanisms (penetrating, chemical, blast), and are limited in scalability of injury severity. We describe a scalable blunt-force TBI model that exhibits a wide range of human clinical pathologies and allows for the study of both injury pathology/progression and mechanisms of regenerative recovery. We modified the Marmarou weight drop model for adult zebrafish, which delivers a scalable injury spanning mild, moderate, and severe phenotypes ...


Investigating Local Adaptation To Hypoxia Stress In The Eastern Oyster Through Comparative Transcriptomics, Heather Nichole Smith 2021 Louisiana State University and Agricultural and Mechanical College

Investigating Local Adaptation To Hypoxia Stress In The Eastern Oyster Through Comparative Transcriptomics, Heather Nichole Smith

LSU Master's Theses

Climate change represents one of the most important challenges to biodiversity, therefore it is important to understand the mechanisms that allow species to respond to rapid environmental change. Here, we compared two populations of eastern oysters, Crassostrea virginica, from the Gulf of Mexico to study the mechanisms underlying hypoxia tolerance. Using a common garden experiment and comparative transcriptomics, we identified sets of genes involved in the hypoxia response and found differences in both the timing and baseline expression of hypoxia-responsive genes between tolerant and sensitive populations, consistent with a scenario of local adaptation. These genes include the signaling transcription factor ...


The Anti-Dipsogenic And Anti-Natriorexigenic Effects Of Estradiol, But Not The Anti-Pressor Effect, Are Lost In Aged Female Rats, Jessica Santollo, Jason A. Collett, Andrea A. Edwards 2021 University of Kentucky

The Anti-Dipsogenic And Anti-Natriorexigenic Effects Of Estradiol, But Not The Anti-Pressor Effect, Are Lost In Aged Female Rats, Jessica Santollo, Jason A. Collett, Andrea A. Edwards

Biology Faculty Publications

Estradiol (E2) inhibits fluid intake in several species, which may help to defend fluid homeostasis by preventing excessive extracellular fluid volume. Although this phenomenon is well established using the rat model, it has only been studied directly in young adults. Because aging influences the neuronal sensitivity to E2 and the fluid intake effects of E2 are mediated in the brain, we tested the hypothesis that aging influences the fluid intake effects of E2 in female rats. To do so, we examined water and NaCl intake in addition to the pressor effect after central angiotensin II treatment in young (3-4 months ...


Enhancing Existing Isolated Underpasses With Fencing Reduces Wildlife Crashes And Connects Habitat, Bridget M. Donaldson, Kaitlyn E. M. Elliott 2021 Virginia Transportation Research Council

Enhancing Existing Isolated Underpasses With Fencing Reduces Wildlife Crashes And Connects Habitat, Bridget M. Donaldson, Kaitlyn E. M. Elliott

Human–Wildlife Interactions

The impact of wildlife–vehicle collisions on drivers and wildlife populations has been gaining attention in the United States. Given the established success of wildlife crossings with fencing in reducing wildlife crashes and connecting habitat, information is needed on cost-effective means of implementation for departments of transportation. When wildlife crossings are constructed, they are often built into new road projects as a series of 2 or more underpasses and/or overpass structures connected by exclusionary fencing. Given limited transportation budgets and the prevalence of maintenance activities more so than new construction in many states, enhancing existing underpasses on previously constructed ...


Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam 2021 Louisiana State University and Agricultural and Mechanical College

Effects Of Salinity On Eastern Oysters: Locating Lower-Salinity Tolerant Populations And Defining Resource Zones Suitable To Restoration, Fisheries, And Aquaculture., Lauren Swam

LSU Master's Theses

Eastern oysters (Crassostrea virginica) provide valuable ecosystem services and support a productive commercial industry in the northern Gulf of Mexico. Declining abundance from water quality changes and other factors drives development of management and restoration strategies focused on a comprehensive, metapopulation approach. Identifying oyster resource zones based on water quality combined with selective breeding of oysters adapted to specific conditions provides strategies to support aquaculture development and ensure resilient oyster populations and high production. Using 2015-2019 satellite-derived continuous salinity and temperature data for coastal Louisiana, this work created maps defining oyster resource zones supportive of (1) broodstock sanctuary reefs, (2 ...


The Mayfly Newsletter, Donna Giberson 2021 Southwestern Oklahoma State University

The Mayfly Newsletter, Donna Giberson

The Mayfly Newsletter

The Mayfly Newsletter is the official newsletter of the Permanent Committee of the International Conferences on Ephemeroptera.


Assessing Climate Change Impacts On Live Fuel Moisture And Wildfire Risk Using A Hydrodynamic Vegetation Model, Wu Ma, Lu Zhai, Alexandria Pivovaroff, Jacquelyn Shuman, Polly Buotte, Junyan Ding, Bradley O. Christoffersen, Ryan G. Knox, Max Moritz, Rosie A. Fisher 2021 The University of Texas Rio Grande Valley

Assessing Climate Change Impacts On Live Fuel Moisture And Wildfire Risk Using A Hydrodynamic Vegetation Model, Wu Ma, Lu Zhai, Alexandria Pivovaroff, Jacquelyn Shuman, Polly Buotte, Junyan Ding, Bradley O. Christoffersen, Ryan G. Knox, Max Moritz, Rosie A. Fisher

Biology Faculty Publications and Presentations

Live fuel moisture content (LFMC) plays a critical role in wildfire dynamics, but little is known about responses of LFMC to multivariate climate change, e.g., warming temperature, CO2 fertilization, and altered precipitation patterns, leading to a limited prediction ability of future wildfire risks. Here, we use a hydrodynamic demographic vegetation model to estimate LFMC dynamics of chaparral shrubs, a dominant vegetation type in fire-prone southern California. We parameterize the model based on observed shrub allometry and hydraulic traits and evaluate the model's accuracy through comparisons between observed and simulated LFMC of three plant functional types (PFTs) under current ...


Stream Sediment Monitoring In Morehead Kentucky, Kristopher Krolikowski, Jen O'Keefe 2021 Morehead State University

Stream Sediment Monitoring In Morehead Kentucky, Kristopher Krolikowski, Jen O'Keefe

2021 Celebration of Student Scholarship - Oral Presentations

Sediment loads in stream systems play a big role in how overall runoff behaves. Streams naturally transport sediment at various ratios depending on precipitation. When vegetation is removed in upstream environments, sediment loads on streams increase. Sudden increases of sediments in streams can cause many issues, such as flooding or stream re-direction. In Morehead, KY, large-scale logging operations on the ridge above Knapp Avenue and on the ridge above the north end of Allen Avenue have caused increased sediment load in a small stream called Oxley Branch. This stream flows south parallel to Knapp Avenue and along the eastern property ...


The Ecology Of Rural Roads: Effects, Management, And Research, Alisa W. Coffin, Douglas S. Ouren, Neil D. Bettez, Luís Borda-de-Água, Amy E. Daniels, Clara Grilo, Jochen A.G. Jaeger, Laetitia M. Navarro, Haiganoush K. Preisler, Emily Rauschert 2021 Cleveland State University

The Ecology Of Rural Roads: Effects, Management, And Research, Alisa W. Coffin, Douglas S. Ouren, Neil D. Bettez, Luís Borda-De-Água, Amy E. Daniels, Clara Grilo, Jochen A.G. Jaeger, Laetitia M. Navarro, Haiganoush K. Preisler, Emily Rauschert

Biological, Geological, and Environmental Faculty Publications

No abstract provided.


Ahr Expression On Rorc-Expressing Immune Cells Is Essential For I3c-Mediated Protection Against Colitis, Michal C. Williams 2021 University of South Carolina

Ahr Expression On Rorc-Expressing Immune Cells Is Essential For I3c-Mediated Protection Against Colitis, Michal C. Williams

Senior Theses

Colitis is an inflammatory bowel disorder (IBD) whose etiology is attributed to modification in the luminal microbiota and dysregulation in the immune response. Indole is a signaling molecule which is naturally produced by gut luminal microbiota. Indole-3- carbinol (I3C) is a compound commonly found in vegetables and a ligand for the aryl hydrocarbon receptor (AhR). Previous studies have detected decreased expression and activation on the AhR receptor in colitis patients, thought to possibly alter gut microbiota metabolism, subsequently promoting colitis. 1 AhR, expressed in a variety of immune and epithelial cells, contributes to gut homeostasis by affecting vital mediators such ...


College Of Natural Sciences Newsletter, July 2021, College Of Natural Sciences 2021 South Dakota State University

College Of Natural Sciences Newsletter, July 2021, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Volume 2, Issue 7.

Page 1 Dean's Message
Page 2 Celebrating Three Years
Page 3 Summer School Travel
Page 4 Media Coverage of CNS
Page 5 Chemistry Teachers Visit
Page 5 Remembering Dr. Warren Hein
Page 6 Research Spotlights: Undergraduate Summer Experiences
Page 7 Open PRAIRIE Data; Grants Awarded in CNS


Lead And Cadmium Detoxification By Halophilic Bacteria Isolated From Solar Salterns In Lebanon, Nadine G. Zmorrod N. G. Zmorrod, Nawal Al Hakawati, Ranya A. Amer, Hoda H. Yusef 2021 PhD Candidate , Faculty of Science , Beirut Arab University, Beirut, Lebanon

Lead And Cadmium Detoxification By Halophilic Bacteria Isolated From Solar Salterns In Lebanon, Nadine G. Zmorrod N. G. Zmorrod, Nawal Al Hakawati, Ranya A. Amer, Hoda H. Yusef

BAU Journal - Science and Technology

Water contamination by heavy metals has gained considerable attention globally. These inorganic pollutants can enter the aquatic environments via different routes thereby threatening biodiversity and human health. Lead and cadmium are hazardous pollutants where their removal by traditional techniques is identified to be costly and ineffective. However, bioremediation by extremophilic microorganisms is considered to be a promising technique as they have considerable potentials to grow in harsh environmental conditions. The present study deals with the isolation of halophilic bacterial isolates from solar salterns in North Lebanon. The isolate H1S9 was identified as Halomonas venusta H9 after showing tolerance to 500 ...


Yakety Sacs: Laryngeal Air Sac Usage In Great Apes, Chelsea Trenbeath 2021 Kennesaw State University

Yakety Sacs: Laryngeal Air Sac Usage In Great Apes, Chelsea Trenbeath

Master of Science in Integrative Biology Theses

Except for humans, extant great apes have evolutionarily conserved lateral ventricular air sacs extending from laryngeal saccules. Humans are the only species of Hominidae that lack this anatomical feature attached to the primary vocal apparatus. As we are the only species that produces spoken language, this association has led to the hypothesis that the loss of lateral ventricular air sacs was necessary for the evolution of spoken language. However, why these sacs are conserved in all other hominids remains unclear. Computer modeling has indicated that air sacs may increase resonance properties, but there are no data from great apes indicating ...


Digital Commons powered by bepress