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2025

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Articles 12151 - 12180 of 12446

Full-Text Articles in Life Sciences

A Novel Silver-Ruthenium-Based Antimicrobial Kills Gram-Negative Bacteria Through Oxidative Stress-Induced Macromolecular Damage, Patrick O. Tawiah Jan 2025

A Novel Silver-Ruthenium-Based Antimicrobial Kills Gram-Negative Bacteria Through Oxidative Stress-Induced Macromolecular Damage, Patrick O. Tawiah

Theses and Dissertations

The rise in drug-resistant bacteria, together with the decline in antibiotic development, requires new strategies for infectious disease control. Gram-negative pathogens are particularly challenging to combat due to their outer membrane. This study highlights the effectiveness of the silver-containing antimicrobial AGXX® against the Gram-negative bacterium Escherichia coli. AGXX® is a promising silver coating that presumably kills bacteria through the generation of reactive oxygen species (ROS). However, neither AGXX®’s mode of action is fully understood, nor have its effects on Gram-negative bacteria or bacterial response and defense mechanisms towards AGXX® been studied in detail. Here, I report that the bactericidal …


Converting Cover Crop Biomass To Biogas And Volatile Fatty Acids, Tuba Yasmin Lubna Jan 2025

Converting Cover Crop Biomass To Biogas And Volatile Fatty Acids, Tuba Yasmin Lubna

Theses and Dissertations

Cover crops are commonly used for their environmental benefits, including improved soil health and reduced soil erosion. However, there is limited use for the aboveground biomass, except for oilseed crops. The objectives of this study were to (1) characterize the selected winter cover crop biomass at three growth stages, (2) evaluate the biogas and volatile fatty acids (VFAs) yield, and (3) examine the concurrent alkali pretreatment and ensiling effects on biogas yield. Wild pennycress, golden pennycress, CoverCressTM, annual ryegrass, cereal rye, pea, and clover biomass were harvested at three growth stages. Results showed that biogas yield increased with …


Stress And Behavior In Beef Calves During Weaning, Kathleen E. Tierney Jan 2025

Stress And Behavior In Beef Calves During Weaning, Kathleen E. Tierney

Theses and Dissertations

Animal welfare in commercial livestock operations has been an increasing topic of concern. It is well known that stress can have significant behavioral and physiological repercussions. It is especially important in commercial operations to reduce stress, as animal efficiency is the leading priority. In an effort to reduce stress on animals and improve welfare in livestock operations, several studies have evaluated common husbandry practices. One of the most widely studied practices is weaning, which encapsulates the process of removing the young from the dam. Several studies have evaluated the effects of weaning on beef cattle through a variety of behavioral …


Exploring Biostimulant Efficacy Under Limited Fertilizer And Water In Utah's Watermelon Production, Evan Christensen, Milena Oliveira, Prakriti Nepal, Youping Sun Jan 2025

Exploring Biostimulant Efficacy Under Limited Fertilizer And Water In Utah's Watermelon Production, Evan Christensen, Milena Oliveira, Prakriti Nepal, Youping Sun

Plants, Soils and Climate Student Research

The western U.S. has recently experienced some of the driest conditions on record, and Utah has been in a multi-year drought (2019-2023) that affected the agricultural sector, including vegetable producers. While vegetables are not a primary agricultural crop in Utah, they are still an important part of the horticultural economy with 763 farms growing 6,138 acres. As the fourth largest acreage vegetable crop in Utah (almost 10% of the acreage) watermelon and related crops in the gourd family Cucurbitaceae (nearly 36% of total vegetable acreage) are important to vegetable growers. Watermelon is a water-intensive crop and requires an adequate supply …


Scalable Fabrication Of High-Payload Dendrimer-Based Nanoparticles For Targeted Atherosclerosis Therapy, Huari Kou, Lin Qi, Da Huang, Jiandong Wu, Honglan Shi, Hu Yang Jan 2025

Scalable Fabrication Of High-Payload Dendrimer-Based Nanoparticles For Targeted Atherosclerosis Therapy, Huari Kou, Lin Qi, Da Huang, Jiandong Wu, Honglan Shi, Hu Yang

Chemistry Faculty Research & Creative Works

Nanoparticle-based therapeutics hold promise for the treatment of atherosclerosis, but challenges such as low drug-loading capacity and a lack of scalable, controllable production hinder their clinical translation. Flash nanoprecipitation, a continuous synthesis method, offers a potential solution for scalable and reproducible nanoparticle production. In this study, we employed a custom-designed multi-inlet vortex mixer to perform cross-linking reaction-enabled flash nanoprecipitation, facilitating controlled and scalable synthesis of cross-linked Poly amidoamine (PAMAM) dendrimer nanoparticles. Notably, this approach allows simultaneous nanoparticle cross-linking and drug loading in a single step. The mannose moiety enabled specific targeting of macrophages via mannose receptors, enhancing the localization of …


Fecal Glucocorticoid Metabolite And T3 Profiles Of Orphaned Elephants Differ From Non-Orphaned Elephants In Zambia, Daniella E Chusyd, Janine L Brown, Steve Paris, Nicole Boisseau, Webster Mwaanga, Moses Kasongo, Lisa Olivier, Stephanie L Dickinson, Bailey Ortyl, Tessa Steiniche, Steven N Austad, David B Allison, Michael D Wasserman Jan 2025

Fecal Glucocorticoid Metabolite And T3 Profiles Of Orphaned Elephants Differ From Non-Orphaned Elephants In Zambia, Daniella E Chusyd, Janine L Brown, Steve Paris, Nicole Boisseau, Webster Mwaanga, Moses Kasongo, Lisa Olivier, Stephanie L Dickinson, Bailey Ortyl, Tessa Steiniche, Steven N Austad, David B Allison, Michael D Wasserman

Children’s Nutrition Research Center Staff Publications

Background: Elephants provide valuable insight into how early-life adverse events (ELAEs) associate with animal health and welfare because they can live to advanced ages, display extensive cognitive and memory capabilities, and rely heavily on social bonds. Although it is known that African savanna elephants that experienced ELAEs, such as being orphaned due to human activities, have altered behavioral outcomes, little is known regarding the physiological consequences associated with those stressors.

Methods: We compared fecal glucocorticoid (fGCM) and thyroid (fT3) metabolites as well as body condition scores (BCS) in rescued and rehabilitated orphaned (early-dry season: n = 20; late-dry season: n …


Mapping Epidermal And Dermal Cellular Senescence In Human Skin Aging, Grace T Yu, Clarisse Ganier, David B Allison, Tamara Tchkonia, Sundeep Khosla, James L Kirkland, Magnus D Lynch, Saranya P Wyles Jan 2025

Mapping Epidermal And Dermal Cellular Senescence In Human Skin Aging, Grace T Yu, Clarisse Ganier, David B Allison, Tamara Tchkonia, Sundeep Khosla, James L Kirkland, Magnus D Lynch, Saranya P Wyles

Children’s Nutrition Research Center Staff Publications

Single-cell RNA sequencing and spatial transcriptomics enable unprecedented insight into cellular and molecular pathways implicated in human skin aging and regeneration. Senescent cells are individual cells that are irreversibly cell cycle arrested and can accumulate across the human lifespan due to cell-intrinsic and -extrinsic stressors. With an atlas of single-cell RNA-sequencing and spatial transcriptomics, epidermal and dermal senescence and its effects were investigated, with a focus on melanocytes and fibroblasts. Photoaging due to ultraviolet light exposure was associated with higher burdens of senescent cells, a sign of biological aging, compared to chronological aging. A skin-specific cellular senescence gene set, termed …


Analisis Situasi Masalah Penyakit Infeksi Menular Seksual Di Kota Bogor Tahun 2024, Wardiman Wardiman, Ratna Djuwita, Bai Kusnadi Jan 2025

Analisis Situasi Masalah Penyakit Infeksi Menular Seksual Di Kota Bogor Tahun 2024, Wardiman Wardiman, Ratna Djuwita, Bai Kusnadi

Jurnal Epidemiologi Kesehatan Indonesia

Abstrak

Infeksi menular seksual (IMS) masih menjadi tantangan kesehatan global, termasuk di Indonesia, terutama pada kelompok usia produktif 15-49 tahun. Di Kota Bogor, angka kasus IMS mengalami peningkatan, namum belum sepenuhnya menggambarkan kondisi yang sebenarnya. Penelitian ini bertujuan untuk menganalisis situasi IMS secara mendalam dan menetapkan prioritas masalah kesehatan menggunakan metode PAHO-adapted Hanlon, yang mengacu pada pembobotan Basic Priority Rating (BPR) berdasarkan lima kriteria utama, yaitu, A=Masalah utama; B=Keseriusan masalah; C=Efektivitas intervensi; E=Ketidakadilan; F=Kapasitas institusi dalam mengatasi masalah. Penelitian ini dilaksanakan di Dinas kesehatan Kota Bogor pada Oktober 2024 hingga Januari 2025, dengan pendekatan kualitatif dan kuantitatif, serta disajikan secara …


Accurate Body Weight Class Prediction From Mirna And Gene Expression In Blood And Saliva Samples, Kimberly Lettner Jan 2025

Accurate Body Weight Class Prediction From Mirna And Gene Expression In Blood And Saliva Samples, Kimberly Lettner

Master of Science in Forensic Science Directed Research Projects

miRNA interference on protein abundance related to glucose uptake and lipid production has been evaluated in biomedical research and linked to metabolic disorders like severe obesity. The direct regulation of protein abundance caused by miRNAs on a person’s metabolism can lead to an increased weight and overall size. Body size, measured by BMI, provides additional physical descriptions that can be combined with hair color, eye color, age, and skin pigment to aid investigations of unidentified remains or unknown suspects not found in a database. The purpose of this project was to evaluate the miRNA expression of target biomarkers in dried …


Biodistribution And Method Validation Of Xylazine In A Mouse Model Using Liquid-Chromatography-Quadrupole-Time Of Flight Mass Spectrometry, Julia E. Perschbacher Jan 2025

Biodistribution And Method Validation Of Xylazine In A Mouse Model Using Liquid-Chromatography-Quadrupole-Time Of Flight Mass Spectrometry, Julia E. Perschbacher

Master of Science in Forensic Science Directed Research Projects

Xylazine is a nonopioid veterinary sedative and an α2 adrenergic receptor agonist. It emerged in the opioid epidemic as an adulterant of illicit fentanyl. As xylazine becomes more involved in fatal overdoses, it is relevant to elucidate its biodistribution post-exposure due to its exacerbation of adverse events, namely respiratory depression, as xylazine’s contributions to existing adverse effects of synthetic opioids is understudied. A bioanalytical method to quantify xylazine and select metabolites in tissue using LC-QToF was validated and applied to a preclinical mouse model in order to characterize xylazine’s biodistribution in whole blood and six tissues at a dose known …


Associations Between Brain White Matter Hyperintensities And Diet Quality In Cognitive Aging: A Cross-Sectional Assessment, Carla V. Urdaneta Jan 2025

Associations Between Brain White Matter Hyperintensities And Diet Quality In Cognitive Aging: A Cross-Sectional Assessment, Carla V. Urdaneta

Honors Undergraduate Theses

Leukoaraiosis, or White Matter Lesions (WMLs)/White Matter Hyperintensities (WMHs), are often considered markers of aging and neurodegeneration. White matter hyperintensities appear as lighter, hyperintense regions on T2-weighted fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) scans and are physiologically characterized as demyelination and axonal loss reflected as microvascular lesions in cerebral white matter (Marseglia et. al., 2019). These anatomical landmarks are most seen in MRIs of elderly individuals. They can be associated with aging and cognitive decline, including affected frontal lobe function and episodic memory in the form of delayed recall performance and are linked to several cardiovascular risk factors, …


Comparative Semiotic Analysis Of Non-Verbal Communication: Apis Mellifera Waggle Dance And Human Kinesic Signaling Systems, Nishtha Tikalal Jan 2025

Comparative Semiotic Analysis Of Non-Verbal Communication: Apis Mellifera Waggle Dance And Human Kinesic Signaling Systems, Nishtha Tikalal

Honors Undergraduate Theses

There are many parallels between two seemingly disparate forms of non-verbal communication: the waggle dance of Apis mellifera (honeybees) and human kinesic signaling systems. Through a comparative semiotic analysis, this research aims to conduct a comparative semiotic analysis, investigating structural and functional similarities between these communication methods, challenging anthropocentric assumptions about meaning making in the natural world. This research employs a meta-synthesis approach, drawn from a methodological literature review to examine historical representations of bee-human relationships, semiotics of non-verbal communication, and the specific mechanisms of the waggle dance and human kinesics. This methodology involves systematic categorization and analysis of extracted …


Developing New Methods For Quantifying Karenia Brevis In Florida Waters, Antonia N. Ferguson Jan 2025

Developing New Methods For Quantifying Karenia Brevis In Florida Waters, Antonia N. Ferguson

Honors Undergraduate Theses

Harmful Algal Blooms (HABs), known as red tides, have long impacted Florida’s coastal ecosystems. Caused by the toxic dinoflagellate Karenia brevis, these blooms are named based on the characteristic red discoloration of coastal waters. Negative impacts of K. brevis range from fish kills, neurotoxic shellfish poisoning, and respiratory irritation in humans. Traditionally, K. brevis monitoring has been conducted weekly by Florida Fish and Wildlife Conservation Commission’s Fish and Wildlife Research Institute (FWC-FWRI) using light microscopy for cell identification and enumeration of collected water samples. However, this method is time-consuming, costly, and relies on deep taxonomic expertise for proper cell …


Salinity Effects On Cu(Ii) Bioremediation By Chlamydomonas Reinhardtii Microalgae, Jennifer Hughes Jan 2025

Salinity Effects On Cu(Ii) Bioremediation By Chlamydomonas Reinhardtii Microalgae, Jennifer Hughes

Honors Undergraduate Theses

Microalgae offer a sustainable approach to wastewater treatment by removing pollutants such as excess nutrients, CO₂, and heavy metals. Among various species, Chlamydomonas reinhardtii shows strong potential in removing Cu(II) ions from wastewater. In addition, salinity stress in C. reinhardtii has been linked to morphological and metabolic changes that enhance lipid and phytochemical production. While salinity stress has been studied for enhancing biofuel production, its impact on microalgal removal of heavy metals, particularly Cu(II), remains largely unexplored. Understanding how varying salinity conditions affect both algal growth and the efficiency of Cu(II) remediation could provide critical insights for improving integrated wastewater …


Characterization Of Major Foliar Fungal Species Affecting Cucurbits In South Dakota, Janani Perera Waduwarage Dona Jan 2025

Characterization Of Major Foliar Fungal Species Affecting Cucurbits In South Dakota, Janani Perera Waduwarage Dona

Electronic Theses and Dissertations

Cucurbit crops comprise the largest area in vegetable production in South Dakota (USDA 2022). Information on the prevalence, distribution, and fungicide sensitivity of their fungal pathogens are unknown. This study characterized the major foliar fungal species affecting cucurbits in South Dakota through a 2-year, state-wide survey. Between 2023 and 2024, 789 leaves were recovered from pumpkin, cucumber, watermelon, squash, and bottle gourd. Alternaria spp. (70.72% of leaves) Fusarium spp. (6.84%), Podosphaera xanthii (4.18%), both Alternaria spp. and Fusarium spp. (3.42%), and both Alternaria spp. and Podosphaera xanthii (1.90%), Stagonosporopsis spp. (1.27%) and other genera of fungi (4.94%) were identified using …


Spatiotemporal Habitat Use, Sex-Specific Movement, And Site Fidelity Of Walleye In Lake Sharpe, Sd, Carter S. Dollen Jan 2025

Spatiotemporal Habitat Use, Sex-Specific Movement, And Site Fidelity Of Walleye In Lake Sharpe, Sd, Carter S. Dollen

Electronic Theses and Dissertations

Walleye Sander vitreus are a popular sportfish among anglers in South Dakota with large economic impacts to local communities. A popular destination for Walleye anglers is Lake Sharpe, a 25,000-ha reservoir on the Missouri River, in central South Dakota. Gill net catches in Lake Sharpe show high annual variation, prompting concern that gill net catch rates may be poorly related to population abundance. A better understanding of Walleye movement and distribution could lead to increased precision in annual abundance estimates and improved active management that increases angler success. The goals of this study were: 1) determine spatiotemporal movement patterns of …


Quantifying Avian And Vegetation Communities On Agricultural Conservation Easement Wetlands In Eastern South Dakota, Katherine Millman Jan 2025

Quantifying Avian And Vegetation Communities On Agricultural Conservation Easement Wetlands In Eastern South Dakota, Katherine Millman

Electronic Theses and Dissertations

The Prairie Pothole Region of eastern South Dakota contains numerous small depressional wetlands, colloquially known as potholes, that provide important ecosystem services, including water storage, water quality improvement, and wildlife habitat. The Agricultural Conservation Easement Program (ACEP) was established by the U.S. Department of Agriculture to protect and restore wetlands and grasslands on private land through easements such as Wetland Reserve Easements. Although ACEP requires management practices intended to maintain or improve habitat quality, few studies have evaluated their effectiveness at supporting wildlife communities and vegetation integrity. To address this gap, we evaluated wetlands at 30 ACEP sites and 20 …


Enhancing Alfalfa Persistence In Rangelands: Evaluating Morphological Traits Of Medicago Sativa Subsp. Falcata Germplasm, Abdulallah Mohammed Alomair Jan 2025

Enhancing Alfalfa Persistence In Rangelands: Evaluating Morphological Traits Of Medicago Sativa Subsp. Falcata Germplasm, Abdulallah Mohammed Alomair

Electronic Theses and Dissertations

Rangelands cover nearly half of the Earth’s surface, representing about 54% (79 million km2), and occur in different types and climates worldwide. Alfalfa (Medicago sativa L.) is a major component in rangelands and covers about (320 thousand km2), representing about 0.4% of total global rangeland area. As a critical perennial legume crop, alfalfa can improve soil health by fixing approximately 336 kg/ha/year of nitrogen and sequestering up to 614 kg/ha/year of carbon, while enhancing livestock production due to its high content level of vitamins, magnesium, minerals, fiber, and protein. However, environmental stresses such as drought, freezing, and grazing limit alfalfa …


Epidemiological And Diagnostic Approaches For Soybean Cyst Nematode In South Dakota, Nabina Karki Jan 2025

Epidemiological And Diagnostic Approaches For Soybean Cyst Nematode In South Dakota, Nabina Karki

Electronic Theses and Dissertations

Soybean cyst nematode (SCN), Heterodera glycines (HG) Ichinohe, is an endoparasitic nematode and one of the major yield-limiting pathogens of soybean (Glycine max L.) in the United States. Soybean cyst nematode alone accounts for more than $1.5 billion economic loss annually in North America. First reported in the U.S.A. in 1954 in New Hanover County, North Carolina and later in 1995 in Union County, South Dakota. Prior to this study, SCN has spread in 34 counties in the state. As a soil pathogen, which can adapt to most soil conditions under soybean production and beside soybean, it is hosted on …


Evaluation Of Two Stem Boring Insects In South Dakota: A Survey Of Wheat Stem Sawfly And Determining The Impact Of Planting Date On Dectes Stem Borer Infestations In Sunflowers, Khuma Kumari Bhusal Jan 2025

Evaluation Of Two Stem Boring Insects In South Dakota: A Survey Of Wheat Stem Sawfly And Determining The Impact Of Planting Date On Dectes Stem Borer Infestations In Sunflowers, Khuma Kumari Bhusal

Electronic Theses and Dissertations

Wheat, Triticum aestivum L., and sunflower, Helianthus annuus L., are major crops in South Dakota that are threatened by stem-boring insect pests capable of reducing yield and harvestability. In wheat, the wheat stem sawfly, Cephus cinctus Norton, has long been recognized as a destructive pest in the Northern Great Plains, yet its actual distribution within South Dakota remained uncertain. To determine its presence, a two-year survey was conducted across the state from 2023–2024, during which one to four wheat fields per county were sampled using standardized sweep net transects. Wheat stem sawflies were collected only from Harding and Perkins Counties …


Soybean Meal And Soybean Hulls Inclusion In Swine Diets And The Effects On Performance, Carcass Characteristics, Nutrient Digestibility, Manure Nutrient Output, And Economic Impact, Joseph G. Halbur Jan 2025

Soybean Meal And Soybean Hulls Inclusion In Swine Diets And The Effects On Performance, Carcass Characteristics, Nutrient Digestibility, Manure Nutrient Output, And Economic Impact, Joseph G. Halbur

Electronic Theses and Dissertations

The increasing demand for soybean production in the Midwest, driven by new soybean crushing plants, may reduce the cost of soybean meal (SBM), making it a more accessible and economically viable feed ingredient in swine diets. Replacing dried distillers grains with solubles (DDGS) with SBM and soy hulls at different inclusion rates may influence growth performance, carcass traits, nutrient digestibility, manure nutrient output, pelleting energy use, and economic returns in wean-to-finish pigs. Two experiments were conducted to evaluate these effects. In the first, 566 pigs (PIC × Terminal Duroc, 8.45 and 7.25 kg, 6 weeks of age) were housed in …


Management Strategies To Improve Gastrointestinal Health And Productivity Of Native And Dairy-Derived Steers Fed In Confinement, Becca B. Grimes Francis Jan 2025

Management Strategies To Improve Gastrointestinal Health And Productivity Of Native And Dairy-Derived Steers Fed In Confinement, Becca B. Grimes Francis

Electronic Theses and Dissertations

The objective of this dissertation was to evaluate strategies to mitigate metabolic disorders in confinement fed steers. The first study was conducted on yearling beef steers to investigate the effect of a rumen buffer, calcium magnesium carbonate (CMC), when fed with or without tylosin phosphate (TYL), on growth performance, rumination activity and liver abscess prevalence. Supplementation of a rumen buffer was not an effective alternative to a feed-grade antimicrobial for the control of liver abscesses in beef steers. Supplementation of CMC reduced DMI, thus negatively influencing BW and ADG. No associative effects of CMC and TYL were observed for any …


Impact Of Natural Feed Additives And Monensin Sodium On Growth Performance In Feedlot Cattle, Thiago Lauro Maia Ribeiro Jan 2025

Impact Of Natural Feed Additives And Monensin Sodium On Growth Performance In Feedlot Cattle, Thiago Lauro Maia Ribeiro

Electronic Theses and Dissertations

The objective of this dissertation was to investigate how phytogenic feed additives and a pulse feeding monensin sodium strategy would affect growth performance in the receiving and finishing feedlot phases. Three randomized complete block design feedlot experiments and one pooled analysis were conducted to determine the effects of the feed additives and management strategies used in newly weaned and finishing beef cattle. The objective of these experiments were 1) determine if a blend of capsicum oleoresin, clove essential oil, and garlic essential oil (CCG) influences cattle performance, sera metabolites or health outcomes during the feedlot receiving phase; 2) determine if …


Discovery Of Photosynthetic Oxic N2-Fixation In Cyanobacteria Using Wet Lab And Machine Learning Approaches, James A. Young Iii Jan 2025

Discovery Of Photosynthetic Oxic N2-Fixation In Cyanobacteria Using Wet Lab And Machine Learning Approaches, James A. Young Iii

Electronic Theses and Dissertations

No abstract provided.


In The Footsteps Of Moose: Using Non-Invasive Techniques To Identify Cause-Specific Calf Mortalities And Evaluate Moose (Alces Alces) Movements Pertaining To Mineral Lick Locations On Ancestral Lands Of The Grand Portage Ojibwe, Anna B. Weesies Jan 2025

In The Footsteps Of Moose: Using Non-Invasive Techniques To Identify Cause-Specific Calf Mortalities And Evaluate Moose (Alces Alces) Movements Pertaining To Mineral Lick Locations On Ancestral Lands Of The Grand Portage Ojibwe, Anna B. Weesies

Electronic Theses and Dissertations

Following a sharp moose (Alces alces; mooz, Anishinaabemowin, Ojibwe language) population decline in northeastern Minnesota during the early 2000s, the Grand Portage Band of Lake Superior Chippewa initiated a long-term moose collaring effort to assess survival and mortality causes. Moose are a culturally important species to the Band, with annual subsistence hunts held on the Reservation and adjacent 1854 Ceded Territory. Continued research guides culturally appropriate management decisions aimed at bolstering calf and adult survival, helping to preserve this moose in Minnesota today and for subsequent generations. Chapter 1 identifies cause-specific calf mortality rates in this multi-predator system using minimally …


Characterizing A Free-Roaming Cat Population To Predict Predation Of Threatened Species In An Island Ecosystem, Sarah Gheida Jan 2025

Characterizing A Free-Roaming Cat Population To Predict Predation Of Threatened Species In An Island Ecosystem, Sarah Gheida

Electronic Theses and Dissertations

No abstract provided.


An Integrated Wetland Condition Index And Environmental Metric Framework For The Prairie Pothole Region, Mercedes L. Batalla Jan 2025

An Integrated Wetland Condition Index And Environmental Metric Framework For The Prairie Pothole Region, Mercedes L. Batalla

Electronic Theses and Dissertations

The USDA-NRCS Agricultural Conservation Easement Program (ACEP) assists landowners with protecting, restoring, and enhancing wetlands. Evaluating wetland conservation efforts is crucial for informing future management decisions. However, assessment frameworks vary across regions and among stakeholders. The Prairie Pothole Region is an ecologically unique landscape characterized by its abundance of wetlands that provide important ecosystem services. To evaluate wetlands enrolled in ACEP, I sampled forty-five semi-permanent wetlands in the Prairie Pothole Region from July – August 2023 and 2024. I selected and sampled twenty-six wetlands enrolled in ACEP. Nineteen additional wetlands not enrolled in ACEP were also sampled; these included nine …


The Formation And Degradation Of Carboxysomes During Heterocyst Development In Filamentous Cyanobacteria, Maxwell Anton Jakubiak Jan 2025

The Formation And Degradation Of Carboxysomes During Heterocyst Development In Filamentous Cyanobacteria, Maxwell Anton Jakubiak

Electronic Theses and Dissertations

Photosynthetic carbon (CO2) fixation and solar-powered nitrogen (N2) fixation are foundational biochemical processes that introduce essential elements into the biosphere. While atmospheric dinitrogen gas (N2) is unusable to most organisms, diazotrophs utilize the nitrogenase enzyme to reduce N2 to ammonia. Because all known nitrogenases are highly susceptible to irreversible oxygen inactivation, N2 fixation is generally incompatible with oxygenic photosynthesis. However, several cyanobacteria are both photosynthetic and diazotrophic, balancing these opposing metabolisms by temporally or spatially separating the respective enzymes. Anabaena sp. PCC 7120 is a model multicellular cyanobacterium that grows in filaments of photosynthetic vegetative cells, which respond to nitrogen …


Isolation, Characterization & Identification Of Cultivable Field Pea Seed Bacteria In South Dakota, Diana Wairimu Njuguna Jan 2025

Isolation, Characterization & Identification Of Cultivable Field Pea Seed Bacteria In South Dakota, Diana Wairimu Njuguna

Electronic Theses and Dissertations

Pea (Pisum sativum L.) is a legume, cultivated on over 25 million acres, particularly in Canada, France, China, Russia, and the United States. Its seeds harbor microbiota including bacteria and fungi, either on the surface (epiphytes) or within seed tissues (endophytes). These microbes can be pathogenic or beneficial, enhancing seedling metabolism and protection from environmental stresses. Characterizing beneficial seed microbiota enables development of microbial inoculants for seed treatment. Seeds from 12 varieties (green or yellow seed coats) were harvested from Sturgis and Dakota Lakes in 2021. Epiphytes were extracted using sonication followed by grinding the seeds to obtain endophytes. Isolates …


Cover Cropping Strategies For Improving Weed Suppression, Yashar Askarzadeh Jan 2025

Cover Cropping Strategies For Improving Weed Suppression, Yashar Askarzadeh

Electronic Theses and Dissertations

Cover crops (CCs) play an essential role in sustainable agriculture by providing multiple ecosystem services. However, adoption remains low due to concerns about economic returns, management complexity, and potential yield reductions in cash crops. Applying CCs uniformly across fields without accounting for spatial variability can result in inconsistent outcomes. A precision cover cropping system (PCCS), which incorporates site-specific management zones (MZs), offers a more targeted approach to improving performance while minimizing costs and uncertainties. This study explores the interaction between CCs and field variability through complementary field and greenhouse experiments. The field experiment demonstrates that field heterogeneity significantly influences CC …