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Full-Text Articles in Life Sciences

Identifying Notch-Regulated Genes Using A Specific Notch Signaling Inhibitor, Hammed Gafar Jan 2025

Identifying Notch-Regulated Genes Using A Specific Notch Signaling Inhibitor, Hammed Gafar

EWU Masters Thesis Collection

Bone remodeling is a dynamic process that requires a balance between bone resorption by osteoclasts and bone formation by osteoblasts to maintain skeletal integrity. Disruptions to this equilibrium can lead to pathological conditions such as osteoporosis. Osteoclasts originate from macrophages, and their differentiation is regulated by several signaling pathways, notably the notch signaling pathway. Gamma-secretase, an enzyme crucial for initiating notch signaling, can be inhibited by DAPT. However, DAPT also targets non-Notch substrates, complicating the identification of genes specifically regulated by Notch. To address this limitation, this study employed IMR-1A, a selective Notch pathway inhibitor that disrupts the assembly of …


The Effects Of Strip Clearcutting On Natural And Artificial Northern Red Oak Regeneration In A Central Appalachian Hardwood Stand, Patrick Aaron Plaugher Jan 2025

The Effects Of Strip Clearcutting On Natural And Artificial Northern Red Oak Regeneration In A Central Appalachian Hardwood Stand, Patrick Aaron Plaugher

Graduate Theses, Dissertations, and Problem Reports (ETD)

There are well-known difficulties associated with regenerating oak stands throughout the Central Hardwoods region. To successfully regenerate oak, competitive sources of advance reproduction are required ahead of harvesting—a condition that is rarely present, especially on productive sites. While treatments that enhance seedling competitiveness (e.g., midstory removals, burning, vegetation control) are available, in practice, these are rarely implemented and/or effective because of large treatment costs and/or because they require delaying harvest.

As a potential alternative practice, we report the 10-yr results of a strip clearcut regeneration method. This method removes alternating 45-m wide strips across a mixed Appalachian hardwood …


Raman Spectroscopy For Rapid Quantification Of Macronutrients In Heirloom Beans, K. Chandler Williams Jan 2025

Raman Spectroscopy For Rapid Quantification Of Macronutrients In Heirloom Beans, K. Chandler Williams

Graduate Theses, Dissertations, and Problem Reports (ETD)

Quantification of macronutrients in food requires a large investment in facilities and instrumentation as well as ongoing expenses of labor, reagents, and hazardous waste disposal. These costs pose a significant barrier to determining macronutrient quantities in the thousands of uncharacterized landrace and heirloom crops and discourage traditional crop breeding projects from ensuring that their selected crops maintain desirable macronutrient profiles in addition to target agronomic traits. Our objective was to test whether a hand-held Raman spectrometer—a technology which has found use in plant disease diagnostics but remains largely overlooked in nutrient quantification-- could provide a feasible means for quantifying the …


Identification Of A Serine Protease Involved In Spinosad Degradation In The Yellow Fever Mosquito, Aedes Aegypti, Hongxiao Yu, Caixia Peng, Zhaohui Chen, Jie Li, Yunqi Li, Xiaojing Zhu, Yuqi Huang, Linlong Jiang, Pablo Sobrado, Jianqiang Lan, Yingying Guo, Qian Han Jan 2025

Identification Of A Serine Protease Involved In Spinosad Degradation In The Yellow Fever Mosquito, Aedes Aegypti, Hongxiao Yu, Caixia Peng, Zhaohui Chen, Jie Li, Yunqi Li, Xiaojing Zhu, Yuqi Huang, Linlong Jiang, Pablo Sobrado, Jianqiang Lan, Yingying Guo, Qian Han

Chemistry Faculty Research & Creative Works

Spinosad is a widely used insecticide effective in controlling Aedes aegypti populations, but the molecular mechanisms underlying resistance remain poorly understood. This study explores the role of a serine protease, AeaSP (AAEL002624), in the potential detoxification ability of spinosad. Our results showed the crude protein of Ae. aegypti degraded approximately 48% of spinosad in vitro within 1 h; based on our previous research, AeaSP was believed to be potentially involved in the degradation of spinosad. Subsequently, AeaSP was recombinantly expressed in vitro, and its enzymatic activity was tested using BAEE as a substrate, with a Michaelis constant (KM) of 0.88 …


Descripción De Una Nueva Especie De Tetralicia Harrison (Hemiptera: Aleyrodidae) De Petén, Guatemala, José Francisco García-Ochaeta, Vicente Emilio Carapia-Ruiz Jan 2025

Descripción De Una Nueva Especie De Tetralicia Harrison (Hemiptera: Aleyrodidae) De Petén, Guatemala, José Francisco García-Ochaeta, Vicente Emilio Carapia-Ruiz

Insecta Mundi

Resumen

Se describe una nueva especie de Aleyrodidae, Tetralicia dubeyi Carapia-Ruiz y García-Ochaeta nueva especie, fue encontrada en el envés de las hojas de Hamelia patens Jacq. (Rubiaceae) en San José, Jobompiche, Petén, Guatemala. Esta nueva especie es incluida en el grupo abnormis del género Tetralicia Harrison. Se ilustran con fotografías las estructuras morfológicas del pupario, se discute la relación con especies cercanas y se proporciona una clave para la identificación de los grupos y especies del grupo abnormis.

Abstract

A new species of Aleyrodidae, Tetralicia dubeyi Carapia-Ruiz y García-Ochaeta new species, was found on the underside of the …


Descriptions Of Four New Species Of Leptophloeus Casey (Coleoptera: Laemophloeidae) From The United States, Michael C. Thomas, Kyle E. Schnepp Jan 2025

Descriptions Of Four New Species Of Leptophloeus Casey (Coleoptera: Laemophloeidae) From The United States, Michael C. Thomas, Kyle E. Schnepp

Insecta Mundi

Four new species of Leptophloeus Casey (Coleoptera: Laemophloeidae) are described: L. barbarus Thomas and Schnepp is described from Florida; L. glacialis Thomas and Schnepp is described from Alaska; L. peregrinus Thomas and Schnepp is described from Hawaii; and L. shoshone Thomas and Schnepp is described from Wyoming. Diagnoses and figures are provided for the new species.


On The Paratypes And Distribution Of Hemipeplus Quadricollis Pollock, 1999 (Coleoptera: Mycteridae: Hemipeplinae): Does It Occur In Peru?, Sajan Kc Jan 2025

On The Paratypes And Distribution Of Hemipeplus Quadricollis Pollock, 1999 (Coleoptera: Mycteridae: Hemipeplinae): Does It Occur In Peru?, Sajan Kc

Insecta Mundi

Hemipeplus quadricollis Pollock, 1999 (Coleoptera: Mycteridae: Hemipeplinae), was originally described from Rondonia State, Brazil, as its type locality, with 10 paratypes: eight from Brazil (Rondonia State) and two from Peru (Madre de Dios and Loreto departments). However, one of the paratypes from Peru (Madre de Dios) was later identified as a cryptic species, Hemipeplus pseudoquadricollis KC and Pollock, 2025. This raises questions about the single remaining paratype from Peru—whether the species truly occurs in Peru—and how many of the paratypes of H. quadricollis are actually H. quadricollis. In this study, all seven remaining paratypes of H. …


First Report Of Corn Leafhopper (Hemiptera: Cicadellidae) In The Usa Midwest Suction Trap Network, Doris M. Lagos-Kutz, Isabel Plasencia, Christopher H. Dietrich, Joseph Laforest, Brian Mccornack, Erin Hodgson, Raul T. Villanueva, Nicholas J. Seiter, Anthony M. Mcmechan, Michael S. Crossley, Steven J. Clough Jan 2025

First Report Of Corn Leafhopper (Hemiptera: Cicadellidae) In The Usa Midwest Suction Trap Network, Doris M. Lagos-Kutz, Isabel Plasencia, Christopher H. Dietrich, Joseph Laforest, Brian Mccornack, Erin Hodgson, Raul T. Villanueva, Nicholas J. Seiter, Anthony M. Mcmechan, Michael S. Crossley, Steven J. Clough

Insecta Mundi

Corn leafhopper, Dalbulus maidis (DeLong and Wolcott) (Hemiptera: Cicadellidae), is native to Central and South America, but invasive in the United States. This species is a threat to corn, Zea mays L., one of the main crops of economic importance in the US, because it is also a vector of three pathogens responsible for corn stunt diseases complex: corn stunt spiroplasma (CSS), maize bushy stunt phytoplasma (MBSP), and maize rayado fino virus (MRFV). Therefore, monitoring the dispersal of this pest is necessary to document its geographic expansion and anticipate the incidence of corn stunt disease. Based on trap catches obtained …


Distributional Records Of False Click Beetles (Coleoptera: Eucnemidae) From Western North Carolina, John M. Leavengood Jr., Robert L. Otto, Mary Kait Brown Jan 2025

Distributional Records Of False Click Beetles (Coleoptera: Eucnemidae) From Western North Carolina, John M. Leavengood Jr., Robert L. Otto, Mary Kait Brown

Insecta Mundi

Two new state records (North Carolina) and eight total species of false click beetles (Coleoptera: Eucnemidae) are reported from a survey site in western North Carolina. Updated distributions are provided for each species.


Group And State-Specific Estimation In Animal Movement Models Using A Bayesian Approach, Anita Bhandari Sharma Jan 2025

Group And State-Specific Estimation In Animal Movement Models Using A Bayesian Approach, Anita Bhandari Sharma

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This research study investigates statistical approaches for modeling the movement patterns of white-tailed deer in Louisiana using GPS tracking data. We start by classifying the latent behavioral states using a hidden Markov model (HMM) and then integrate those inferred states into a state-dependent step selection framework to evaluate the land cover preferences. Standard HMMs, however, assume the same movement patterns for all animals, overlooking the differences due to characteristics such as sex, age, breeding season, etc.

To address this limitation, we extend the modeling framework to incorporate the group-level structure defined by similar characteristics or conditions to assess whether such …


Geometric Modeling, Reconstruction And Evaluation Of Maize Leaf Morphology In 3d, Zhaocheng Xiang Jan 2025

Geometric Modeling, Reconstruction And Evaluation Of Maize Leaf Morphology In 3d, Zhaocheng Xiang

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Maize is a vital crop for global food security, yet quantitative characterization of its three-dimensional (3D) morphology remains a major challenge due to the geometric complexity of curved leaf structures and occlusions during data collection. This work presents an integrated framework for the digital reconstruction, parametric modeling, and functional analysis of maize leaf morphology and canopy architecture, advancing the precision and interpretability of phenotyping and modeling in smart agriculture.

First, we propose a descriptive and parametric model that represents maize leaves through three fundamental components: midrib, cross-section, and blade contour. Each is described by geometric curves and controlled by biologically …


All For One And One For Gall: Getting Kids Excited About Plant-Insect Interactions, Natalie D. Tessicini Jan 2025

All For One And One For Gall: Getting Kids Excited About Plant-Insect Interactions, Natalie D. Tessicini

Department of Entomology: Distance Master of Science Projects

Insect biodiversity is on a decline globally. In order to care about insects, the population must know about them. Creating interest starts with young children and students, using age-appropriate resources and lesson plans. Ensuring that future generations are curious about entomology and not driven away from it is integral to building a future where the public protects the environment. I will add to the available tools by creating my own non-fiction children’s book on under-explored entomology topics.


Cell Competition Eliminates Aneuploid Human Pluripotent Stem Cells, Amanda I. Ya Jan 2025

Cell Competition Eliminates Aneuploid Human Pluripotent Stem Cells, Amanda I. Ya

Dartmouth College Ph.D Dissertations

Aberrant mitotic chromosome segregation results in the generation of cells with aneuploidy, an incorrect number of chromosomes. Aneuploidy can compromise the viability of the developing embryo and is the leading cause of pregnancy loss, failed embryo implantation, and congenital birth defects. Yet, widescale analysis of human embryos from in vitro fertilization (IVF) clinics suggests that aneuploidy is common, with upwards of 70% of preimplantation embryos being aneuploid.

Mitotic chromosome missegregation during post-zygotic development results in mosaic embryos made up of both diploid and aneuploid cells. Strikingly, upon transplant for pregnancy, mosaic embryos have been reported to result in healthy birth …


Engineering Extracellular Vesicles (Evs) To Combat Infection And Inflammation In Cystic Fibrosis, Sharanya Sarkar Jan 2025

Engineering Extracellular Vesicles (Evs) To Combat Infection And Inflammation In Cystic Fibrosis, Sharanya Sarkar

Dartmouth College Ph.D Dissertations

Cystic Fibrosis (CF) is a multisystemic genetic disorder caused by mutations in the CFTR gene, resulting in chronic pulmonary infections, hyperinflammation, and progressive lung damage. Among the pathogens that colonize CF lungs, Pseudomonas aeruginosa (P. aeruginosa) is predominant, infecting over 50% of adults with CF and developing antibiotic resistance over time. Current modulator therapies fail to address persistent bacterial infections, chronic inflammation, or irreversible lung damage, underscoring the need for novel therapeutic strategies. In our previous in vitro studies, we demonstrated that extracellular vesicles (EVs) secreted by primary Human Bronchial Epithelial Cells (HBECs) inhibit P. aeruginosa growth by reducing the …


Biochemical And Molecular Analysis Of Anr-Dependent Microoxic Fitness Factors In Pseudomonas Aeruginosa, Stacie E. Balsam Jan 2025

Biochemical And Molecular Analysis Of Anr-Dependent Microoxic Fitness Factors In Pseudomonas Aeruginosa, Stacie E. Balsam

Dartmouth College Ph.D Dissertations

Pseudomonas aeruginosa is a prominent opportunistic pathogen that is often found in microoxic environments like sites of infection and colony biofilms. P. aeruginosa can grow at oxygen (O2) at concentrations as little as 3 μM and also grows anaerobically by generating energy using nitrate as an alternate electron acceptor. An important way P. aeruginosa adapts to low O2 is through Anr, a transcription factor that upregulates many genes important for microoxic and anoxic fitness.

Specifically, Anr regulates mhr which encodes a hemerythrin protein (Mhr) that binds O2 with affinities relevant to microoxia and is also necessary for full fitness of …


Spatial Analysis Of American Chestnut (Castanea Dentata) Distribution And Ecology In Kentucky’S Federal Lands, Jacob Raymond Pease Jan 2025

Spatial Analysis Of American Chestnut (Castanea Dentata) Distribution And Ecology In Kentucky’S Federal Lands, Jacob Raymond Pease

Murray State Theses and Dissertations

Anthropogenic factors have been the cause of the decline of tree species across the globe. From unsustainable logging and development to disease and improper management, threats to forests have taken their toll. The American chestnut (Castanea dentata) was once an integral basal tree species in Appalachian forests, but chestnut blight drove the species to functional extinction by the mid-1900s. The recent creation of genetically modified chestnuts gives hope for future restoration of the species throughout its historical range. Despite blight resistance, effective restoration will require optimal site selection for finding and planting chestnuts, which will maximize limited resources. …


Equine Hair Cortisol Concentration And The Effects Of Season, Storage Method, And Personality Traits, Savannah M. Rivers, Grace A. Robertson, Thomas Powell, Lydia O'Sullivan, Shea Porr Jan 2025

Equine Hair Cortisol Concentration And The Effects Of Season, Storage Method, And Personality Traits, Savannah M. Rivers, Grace A. Robertson, Thomas Powell, Lydia O'Sullivan, Shea Porr

Murray State Theses and Dissertations

Stress exists everywhere, for survival, adaptation is necessary. These adaptations directly reflected the stresses the animal experienced and demonstrated the ability to cope. An animal that could not cope could not survive. Stressful experiences resulted in behavior patterns for each animal. Consistent behavior can be defined as personality [1]; therefore, stress could directly influence personality by changing behavior.

Stress research helped analyze and identify animal personality traits, especially horses. Human-horse pairings partially relied on personality traits and, when considered, often led to improvements in welfare [2]. There are various tools to assess personality, one being Equine Personality Assessment [3]. The …


Understanding Bird Diversity: A Modeling Approach In An Urban And Wetland Ecosystem, Clay Bliznick Jan 2025

Understanding Bird Diversity: A Modeling Approach In An Urban And Wetland Ecosystem, Clay Bliznick

Murray State Theses and Dissertations

The global increase in anthropogenically-driven shifts of land cover has resulted in losses to many natural communities such as prairies and wetlands. These ecosystems take on artificially-derived characteristics such as croplands, buildings, and roads to the extent that they no longer resemble the areas they once were. This process often results in the loss of biodiversity, ecological integrity, and valuable ecosystem services in these environments. Attempts to restore the condition and function of these disturbed areas are often implemented, but due to the complexity of factors driving these restorations, there is often a lack of practical insight needed to optimize …


Wildlife Distribution Mapping And Analysis In Gorongosa National Park, Mozambique, Using Site And Satellite Imagery Data, Pinho Joaquim Munhequeira Mr Jan 2025

Wildlife Distribution Mapping And Analysis In Gorongosa National Park, Mozambique, Using Site And Satellite Imagery Data, Pinho Joaquim Munhequeira Mr

Murray State Theses and Dissertations

One of Mozambique's most important conservation sites, Gorongosa National Park has seen critical ecological changes over the past several decades resulting from climate variability, habitat loss, and political instability. This research integrates Geographic Information Systems (GIS) and remote sensing to examine the relationship between vegetation dynamics and wildlife population, and distribution. The main goals of this study are to evaluate the spatial distribution of particular wildlife species: buffalo (Syncerus caffer), elephant (Loxodonta africana), hippopotamus (Hippopotamus amphibius), and zebra (Equus quagga), and determine the impact of vegetation density and land cover on their …


Unraveling Reproductive Complexity: Integrative Assessment Of White Crappie Pomoxis Annularis Spawning Dynamics In Kentucky Lake, Emily A. Freeman Jan 2025

Unraveling Reproductive Complexity: Integrative Assessment Of White Crappie Pomoxis Annularis Spawning Dynamics In Kentucky Lake, Emily A. Freeman

Murray State Theses and Dissertations

In large reservoirs such as Kentucky Lake, White Crappie Pomoxis annularis exhibit complex reproductive dynamics, including variable annual recruitment and frequent skipped or partial spawning events. This study investigates the energetic and environmental factors influencing spawning success in Jonathan Creek, a northern embayment of Kentucky Lake. Using a dual sampling approach, I combined citizen science angler-caught fish during the pre-spawn with trap netting in shallow spawning areas to capture crappie during the full reproductive cycle. Physiological, biometric, and egg analyses revealed that spawning success was driven more by pre-spawn energetic conditions than by the conditions during the spawn. Elevated water …


Introduction To Hydroponics- 2025-2026 Workshop Handbook, Stacy A. Adams Jan 2025

Introduction To Hydroponics- 2025-2026 Workshop Handbook, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Hydroponically grown plants grow faster than traditional production systems, with greater productivity, greater palatability, and having optimal visual character. Three principal components of a system include the plant support platform, a nutrient solution reservoir, and an interface for the root-solution. This publication provides in-depth explanation to system design, evaluation of water quality, nutrient formulation, and prototype systems that can be easily constructed for those wanting to explore hydroponics, such as educators, organizational leaders, or home enthusiasts.


Greenhouse Management For The Smaller Structure--Educational And Hobby, Stacy A. Adams Jan 2025

Greenhouse Management For The Smaller Structure--Educational And Hobby, Stacy A. Adams

Department of Agronomy and Horticulture: Faculty Publications

Greenhouses used for teaching or by hobbyist are smaller than those used for commercial production or found in the retail environment. Structural materials, covering, mechanical equipment, and control systems often are packaged as a kit made available through greenhouse suppliers. Supplier construction services may not be available, in which buyers must use local contractors to complete the installation. Greenhouses are unique structures that differ greatly from sheds or other outbuildings. They have coverings that allow maximum light transmittance, protected from UV degradation, and can handle wide inside to outside temperature extremes. This extension circular provides valuable information on the character, …


Morphology And Synaptic Connections Of A T7 Bipolar Cell In Mouse Retina, Lauren Groen Jan 2025

Morphology And Synaptic Connections Of A T7 Bipolar Cell In Mouse Retina, Lauren Groen

Williams Honors College, Honors Research Projects

This project will aim to identify ribbon outputs and post-synaptic partners of type 7 bipolar cells in a mouse retina. Using the software WebKnossos, a three-dimensional skeleton of three to four type 7 bipolar cells will be traced. Ribbon synapses will then be located along the cells' axon terminals, and the types of cells that are receiving the synaptic output will be identified. The goal of this project is to provide a better understanding of how type 7 bipolar cells interact with other neurons in the inner plexiform layer (IPL) of the retina.


Exploring The Effects Of Road Salt On Earthworm Species, Alea Mry Koston Jan 2025

Exploring The Effects Of Road Salt On Earthworm Species, Alea Mry Koston

Williams Honors College, Honors Research Projects

This study examines the effects of two road salts, sodium chloride (NaCl) and calcium magnesium acetate (CMA), on the health of two earthworm species: Eisenia fetida and Lumbricus terrestris. Over a 4-week period, approximately 168 earthworms were exposed to varying concentrations of either NaCl, CMA, or mixed ratios of both, with a control group included for comparison. The experiment involved monitoring the changes in earthworm weight and measuring their contraction rates to determine physiological responses. Statistical analysis revealed no significant differences in weight or activity between NaCl and CMA treatments for either species. However, higher concentrations of NaCl resulted in …


The Impact Of Seasonal Variation On Body Morphology In Temnothorax Curvispinosus, Chelsea Kalb Jan 2025

The Impact Of Seasonal Variation On Body Morphology In Temnothorax Curvispinosus, Chelsea Kalb

Williams Honors College, Honors Research Projects

This study examines how seasonal variations affect the morphology of Temnothorax curvispinosus (acorn ants) by comparing workers hatched in the spring and in the fall. Colonies will be collected from the Bath Nature Preserve in May and September to represent the different seasonal groups. Morphological traits, such as the head, mesosoma, gaster, antennae, and leg, will be measured using a microscope and an image analysis software. The morphological measurements from each group will then be compared using ANOVA. By exploring how environmental variation influences developmental outcomes in acorn ants, this research contributes to our understanding of phenotypic plasticity and insect …


Pesticide And Pathogen Exposure Causes Idiosyncratic Gene Expression Responses Across Four Diverse North American Bumble Bee Species, Rubén Martín-Blázquez, Sydney A. Cameron, Austin C. Calhoun, James P. Strange, Ben M. Sadd Jan 2025

Pesticide And Pathogen Exposure Causes Idiosyncratic Gene Expression Responses Across Four Diverse North American Bumble Bee Species, Rubén Martín-Blázquez, Sydney A. Cameron, Austin C. Calhoun, James P. Strange, Ben M. Sadd

Faculty Publications – Biological Sciences

Bumble bee (Bombus Latreille) populations of certain species have declined precipitously in North America over several decades. Hypotheses for declines include exposure to the pathogen Nosema bombi and neonicotinoid pesticides. Importantly, populations of some bumble bee species remain stable despite their presumed exposure to these same stressors. We hypothesise that declining and stable species exhibit distinct responses to N. bombi and neonicotinoids, detectable as differential gene expression profiles. To test this, we exposed larvae of Bombus occidentalis (declining) and B. impatiens (stable) to N. bombi and to the neonicotinoid imidacloprid, plus a combination of both. RNA-seq analysis revealed almost …


No Evidence Of Immune Priming In Bumble Bee Hosts Against Novel Exposure To A Honey Bee Virus, Austin Calhoun, Ben M. Sadd Jan 2025

No Evidence Of Immune Priming In Bumble Bee Hosts Against Novel Exposure To A Honey Bee Virus, Austin Calhoun, Ben M. Sadd

Faculty Publications – Biological Sciences

Ongoing global change presents novel challenges to species persistence, including heightened emerging infectious diseases (EID) exposure. While invertebrates lack vertebrate acquired immunity, many species exhibit “immune priming” with enhanced protection to repeated pathogen exposures. This phenomenon could be critical for species of conservation concern, such as for wild bumble bees, where EID risk is amplified through contact with managed bee pollinators. We investigate the potential for immune priming against the honey bee-derived Israeli Acute Paralysis Virus (IAPV) in Bombus impatiens bumble bees. We test the hypothesis that prior pathogen-associated exposure affords greater resistance and tolerance upon secondary pathogen exposure, due …


Assessment Of The Genetic Population Structure And Extent Of Clonality In A Rare Serpentine Endemic, Lathyrus Biflorus T.W. Nelson & J.P. Nelson (Fabaceae), Using Ddrad Sequencing, Ashley Dickinson Jan 2025

Assessment Of The Genetic Population Structure And Extent Of Clonality In A Rare Serpentine Endemic, Lathyrus Biflorus T.W. Nelson & J.P. Nelson (Fabaceae), Using Ddrad Sequencing, Ashley Dickinson

Cal Poly Humboldt theses and projects

Lathyrus biflorus, or the two-flowered pea, is a rare herbaceous perennial restricted to a single population in Northern California. The species is considered critically imperiled but remains unprotected under state or federal endangered species acts. Despite its rarity, little is known about its life history, reproductive biology, or genetic diversity. Using genome-wide reduced representation sequencing, this study aimed to address these gaps by investigating the molecular evidence of clonality, the number and diversity of genets (unique genetic individuals which can be made up of one or many clonal units or ramets), and overall genetic health of the population. My …


Factors Influencing Elk Road Crossing Behavior, Brielle Christine Jaglowski Jan 2025

Factors Influencing Elk Road Crossing Behavior, Brielle Christine Jaglowski

Cal Poly Humboldt theses and projects

Highways fragment habitat and can impose barriers to wildlife. Installing wildlife crossing systems creates opportunities for safe animal movement, improved human safety, and reduced property damage. Research identifying key zones of connectivity can aid in providing recommendations for locations of these systems and other tools to improve highway safety. Although elk-vehicle collisions occur broadly across northwestern California, factors associated with these highway crossing zones have not been studied in this region. To address this gap in research, the objective of this study was to evaluate how environmental and structural factors influence the probability of elk (Cervus canadensis) crossing US-101 in …


Investigating The Refugial River Mouth Hypothesis: Assessing The Effects Of Low Salinity Conditions On The Microscopic Life Stages Of Nereocystis Luetkeana, Duncan Jackson Jan 2025

Investigating The Refugial River Mouth Hypothesis: Assessing The Effects Of Low Salinity Conditions On The Microscopic Life Stages Of Nereocystis Luetkeana, Duncan Jackson

Cal Poly Humboldt theses and projects

Populations of Nereocystis luetkeana (bull kelp) have experienced localized extinction events in northern California since 2014 due to multiple stressor events, including the area’s most severe marine heatwave (MHW) to-date. Previous surveys in the region observed that bull kelp recovered and persisted at river mouths following the 2014-2015 MHW, suggesting that river mouths may serve as refugia – the refugial river mouth hypothesis. My study aimed to assess this hypothesis and the long-term stability of these refugia by studying how freshwater influences communities at these sites and bull kelp recruitment. Field surveys of salinity fluctuation and kelp and sea urchin …