Life Sciences Commons^™

Effects Of Short-Term Pesticides Exposure On Swimming Behavior, Tissue Morphology, Oxidative-Nitrative Stress, Antioxidant Expression, And Cellular Apoptosis In Kidneys Of Goldfish, Esmirna Cantú

Theses and Dissertations

The prevalence of pesticides in the aquatic environment continues to increase due to anthropogenic activities and poses a threat to aquatic organisms. The aim of this study was to determine the short-term exposure (one-week) of pesticide mixtures (metolachlor, linuron, isoproturon, tebucanazole, alconifen, atrazine, pendimethalin; azinphos-methyl) on swimming behaviors, kidney morphology, and expression of nitrotyrosine protein (NTP), dinitrophenyl protein (DNP), superoxide dismutase (SOD), catalase (CAT), renin, and cellular apoptosis in goldfish (Carassius auratus). Results indicated that both low- and high-dose pesticide mixtures decreased the distance swimming behavior. Histological analysis showed pesticide exposure alters kidney morphology. DNP, NTP, and renin expressions, and …

Aedes Aegypti Host Preference On Canines Versus Human Volatile Skin Compounds, Melissa Bernadette Rosalez

Theses and Dissertations

It is critical to understand how Aedes aegypti mosquitoes detect hosts through cues such as volatile skin compounds. In South Texas, evidence suggests that this mosquito is showing a feeding preference for canines over humans. This shift may impact the transmission of Dirofilaria immitis, canine heart worms, in local dog populations. Our study is set to explore Ae. Aegypti attraction to hosts using canine and human volatile compounds. Volatile skin compounds will be collected using a volatile collection system. Compounds will be analyzed using gas chromatography/mass spectrometry. It is anticipated that the main volatile skin compounds amongst humans are nonanal, …

Growth Rates, Morphology, And Potential For Mariculture Of The Southern Population Of Crassostrea Virginica In The Lower Laguna Madre, Texas, Jerad Lee Fuelling

Theses and Dissertations

The Eastern Oyster also known as Crassostrea virginica, is an important resource here in the United States. Historically, this species has been overfished, poorly managed, and plagued by disease. Oyster mariculture is a growing industry here in the United States and is a sustainable solution to producing oysters. Texas has become the last coastal state to legalize oyster mariculture which means there is now a vast coastline with many unique bay systems that are open to this industry. One bay system that is particularly unique is the Lower Laguna Madre which is a hypersaline lagoon. Little is known about …

Overexpression Of Ubtf Correlates With Aggressive Phenotypes Of Prostate Cancer Cells, Guillermo Andres Saldana

Theses and Dissertations

Prostate cancer (PrCa) is one of the most common malignancies in men globally and the second leading cause of cancer associated deaths in developed countries. Accumulating evidence have demonstrated involvement of various molecular and cellular factors in the development, progression and chemoresistance of PrCa and many of them were successfully established as potential molecular targets for therapy. Despite these advancements, the underlying mechanisms of PrCa occurrence is still unclear, which limits the diagnosis and therapy. Therefore, it is an urgent need to discover potential molecular targets which can be used in rational design of new strategies for the prevention and …

Chemical Investigation Of Dichloromethane Extract Of Aloe Vera Peels: An Agricultural Waste, Nazmul Huda

Theses and Dissertations

Aloe barbadensis Miller, commonly called Aloe Vera, is a widely popular succulent plant species cultivated across subtropical regions worldwide from India to the Tex-Mex border. Besides its historical uses, Aloe juice has garnered attention as a potential remedy for various ailments, particularly in treating various skin conditions and facilitating wound recovery, including obesity, diabetes, hepatitis, Crohn's disease, and ulcerative colitis. Regrettably, the agricultural practice following sap extraction involves discarding Aloe vera peels, constituting agricultural waste. As part of our continuous research on extraction, isolation, separation, and spectral characterization of value-added chemicals present in waste botanicals herein, …

Monitoring The Effectiveness Of Wildlife Exits And Bobcat Use Along A South Texas Highway, Jamie E. Langbein

Theses and Dissertations

Roadside exclusion fencing is commonly used to mitigate wildlife road mortalities and property damages caused by wildlife-vehicle collisions. A potential consequence is that animals may become trapped on the road by fencing. On State Highway 100 in South Texas, the Texas Department of Transportation installed ten wildlife exits (WE) allowing animals to exit the roadway through a modified opening in the fence. However, some individuals used the WE to access the roadway. In this study, a new design was implemented, with narrower openings, a ramp and a clear plastic one-way door. While the updated design prevented road access for wildlife, …

Investigating The Localization Of Foxo4 Transcription Factor In U87mg Glioblastoma Cell Line, Millat Jahan

Theses and Dissertations

FOXO transcription factors perform diverse functions that have effects on significant biological processes like stem cell homeostasis, cell cycle, apoptosis, and cell fate determination. This research focuses on FOXO4 that is differentially localized in U87MG glioblastoma cells where FOXO4 is targeted to the nucleus. This research is aimed at investigating the mechanism and localization of FOXO4 in U87MG cell lines. Using chimeric fusion construct, we have mapped regions within FOXO factors that can determine specific cellular localization patterns. Finding the mechanism behind specific nuclear localization of FOXO4 can produce innovative data to better understand the distinctive subcellular localization patterns in …

The Effects Of Low Volume High-Intensity Interval Training Vs. Moderate-Intensity Interval Training With Blood Flow Restriction On Body Composition, Hormone Concentration, And Arterial Elasticity In Overweight And Obese Male Adults, Alexis Lopez

Theses and Dissertations

PURPOSE: This study compared the effects of HIIT and MIIT+BFR on the adaptations in body composition, salivary hormone concentration, peak oxygen uptake, anaerobic parameters, and arterial elasticity in young overweight and obese male adults.

RESULTS: There was a significant increase in total BMC (p<0.01), leg BMC (p<0.05), and trunk BMC (p<0.05) from baseline in response to HIIT. MIIT+BFR significantly increased LFM/TFM Ratio from baseline (p<0.01). HIIT significantly decreased AIx@75 (p<0.05) and CI (p<0.05). There was a significant increase in ISO 180o Away (p<0.05), Thor Begin. (p<0.01), and Thor Mid. (p<0.05) in response to HIIT. MIIT+BFR had a superior increase in Thor Mid. (p<0.05) and significantly increased ISO 180o Toward (p<0.01), VO2peak (p<0.05), and VO2peak:Time (p<0.05). In the last training session, HIIT significantly increased salivary leptin (p<0.05), but MIIT+BFR had a superior increase in salivary leptin (p<0.01) from pre- to post exercise.

CONCLUSION: HIIT significantly improved total BMC, leg BMC, trunk BMC, and AIx@75 but decreased CI from baseline. HIIT increased quad muscle strength, whereas MIIT+BFR increased hamstring muscle strength. HIIT and MIIT+BFR significantly increased peak torque in Thor Mid and salivary leptin. Only MIIT+BFR significantly improved VO2peak.

Fungal Plant Pathogens Affecting Crops In The Lower Rio Grande Valley, Isabel Martinez

Theses and Dissertations

The Lower Rio Grande Valley (LRGV) located in South Texas has a subtropical and humid environment which is conducive for plant disease. In Chapter 1, Southern blight caused by Athelia rolfsii was collected from Edinburg, Texas in tomato and bean crops. The present study focused on assessing the role of temperature on growth and sclerotia production. We found that there is an optimal growing temperature for both hyphal growth and sclerotia production. In Chapter 2, red rot fungal disease was collected from sugarcane in Texas. Morphology, pathogenicity, effects of temperature, and biocontrol agents were assessed. Isolate morphology closely resembled Fusarium …

Vertical Transmission Of Zika Virus In Monodelphis Domestica, Mohini Moulick

Theses and Dissertations

Zika Viral infection in pregnant women may lead to infants born with microcephaly and other neurological complications, making Zika viral research imperative. Prior research demonstrated Monodelphis domestica to be a unique animal model for Zika virus studies, and viral proteins were detected in brain tissue of juveniles after intracerebral inoculation of infants. We wanted to determine if we can detect a viral protein, non-structural protein 1 (NS1), in brain tissue after intraperitoneal inoculation and we found it to be possible through immunohistochemistry (IHC) analysis. We also investigated if inoculated dams (mothers) would give rise to Zika positive pups (natural inoculation), …

Effect Of Pre-Growth Conditions On Foodborne Pathogen Survival Kinetics In Fresh Produce, Avninder Kaur

Theses and Dissertations

World-wide consumption of fresh-cut produce has seen a dramatic increase over the past few decades. However, fresh-cut produce has been implicated in several illness outbreaks due to contamination with foodborne bacterial pathogens. Post-harvest contamination during handling and processing is considered rare but several influencing factors are often overlooked. Specifically, studies have reported the growth, survival, and death kinetics of foodborne bacterial pathogens such as E. coli O157: H7, Salmonella and Listeria monocytogenes in different fresh and fresh-cut produce. The effect of various factors such as storage temperature, time, and relative humidity are widely explored. It is increasingly evident that microbial …

The Effects Of Caffeine On Activity Levels And Motor Behaviors In The Honeybee, Apis Mellifera, Johana Castro

Theses and Dissertations

Caffeine is produced by plants as a defense mechanism against herbivores and pathogens. However, caffeine was found in floral nectar, which contradicts nectar's role in attracting pollinators. Interestingly, low concentrations of caffeine were shown to increase alertness and locomotion in mammals and invertebrates, indicating it may enhance the productivity of pollinators. This investigation examined how caffeine affects activity levels and motor behaviors in the honey bee, Apis mellifera. To test overall activity, forager bees were collected and fed 1 M sucrose to satiation. The following day, bees received 10 µl of 1.0 M sucrose alone or with caffeine ranging from …

Understanding The Distribution And Abundance Of Asclepias Prostrata In South Texas, Elizabeth Ann Gonzalez

Theses and Dissertations

Asclepias prostrata, commonly referred to as prostrate milkweed, is a rare South Texas native plant species. In February of 2023, A. prostrata was listed as a federally endangered species by the U.S. Fish and Wildlife Service. Due to the limited available observations and literature for A. prostrata, this study was completed to bring new information that could be utilized for future restorative efforts. This study includes multiple field observations of the plant’s morphology, plant-insect interactions, extraction and transplanting of the species, and a seed viability study. Results indicate that although A. prostrata has many pressures that limit its …

Tamaulipan Thornforest Restoration: Factors Influencing Restoration Outcomes And Impacts Of Cover Crops During Replanting, Jerald Thomas Garrett

Theses and Dissertations

Though the rate of deforestation has slowed in recent years, it remains a primary cause of land cover change within forest ecosystems. The Lower Rio Grande Valley, Texas (LRGV) has lost nearly 95% of its native thornforest since the early 1900’s due to agricultural and urban expansion. The focus of this study is to assess the current vegetative state of restored thornforest sites located in the eastern LRGV and to evaluate the use of cover crops during replanting of native seedlings. Our assessment of restored thornforest sites revealed actively restored sites demonstrated higher overall averages of richness, abundance, and diversity …

Cover Crops Influence Arthropod Community Dynamics Through Seasonal Variation And Cascading Effects, Adegboyega Fajemisin

Theses and Dissertations

Chapter 1: This chapter gives an overview of how cover crops influence soil’s physical, chemical, and biological properties, and their role on mediating arthropod community dynamics with implications for pest management in the subsequent cash crop.

Chapter 2: This chapter examines the effects of cover-cash crop rotation on arthropod community dynamics on four growers fields in the Lower Rio Grande Valley, Texas. We assessed the impact of cover crops planted in the summer months on the subsequent cash crops planted in the winter. Our results showed that cover crops had a differential effect on the population of beneficials and herbivores …

The Role Of Tc-Ptp-Mediated Suppression Of Autophagy During Skin Carcinogenesis, Obed Asare

Theses and Dissertations

Ultraviolet B (UVB) radiation can distort cellular homeostasis and predispose the skin to carcinogenesis. Amongst the deteriorating effects of the sun’s UVB radiation on cellular homeostasis is the formation of DNA photoproducts such as cyclobutene pyrimidine dimers. These photoproducts can cause significant changes in the structure and conformation of the DNA, inducing gene mutations which may accumulate to trigger the formation of skin cancer. Photoproducts are typically repaired by nucleotide excision repair. Notwithstanding, when the repair mechanism fails, apoptosis ensues to prevent the accumulation of mutations and to restore cellular homeostasis. We have identified T-cell protein tyrosine phosphatase (TC-PTP) as …

Comparative Analysis Of Soil Properties, Microbial Community Composition, And Yield Responses To Cover Crops In Different Ecoregions Of South Texas, Daphne Zapsas

Theses and Dissertations

Comprehensive understanding of soil properties, their interdependencies, and the effects of management practices is crucial for designing sustainable agricultural strategies. By adopting site-specific and need-based practices that enhance soil health, farmers can optimize crop growth, increase yield, and contribute to long-term environmental sustainability. Cover crops have been recognized for enhancing soil fertility, promoting microbial activity, and increasing organic matter content. However, while their effectiveness is well documented in temperate regions with readily available water, their impact in water limited systems in subtropical regions remains mixed. The aim of this study is to assess soil conditions in four different farms across …

Biochar Reduces The Pupation And Eclosion Of A Specialist (Manduca Sexta) And A Generalist Pest (Spodoptera Frugiperda), Nischal Wagle

Theses and Dissertations

Chapter 1: This chapter incorporates detailed information about the biochar concept, its production, composition, and properties, harmful arthropods and their damage, the effect of soil on the arthropod community, and the application of biochar on arthropod control.

Chapter 2: The comprehensive lab experiment was conducted with modified pupation media enriched with walnut shell biochar (Chapter II) to evaluate the effects of biochar on the pupation and eclosion success rates of a specialist (Manduca sexta) and a generalist pest (Spodoptera frugiperda). We found that the biochar treatment led to a significant reduction in pupal mass, adult mass, adult wingspan, body length, …

Soil Moisture Dynamics In Cover Cropping Systems: From Local To Global Scales, Manish Gautam

Theses and Dissertations

Cover cropping systems, which have gained recognition for their ability to enhance soil health and promote sustainability are also associated with potential risks related with declining soil moisture and pose a dilemma for farmers considering the adoption of cover crops in water deficit semi-arid settings worldwide. To address this pressing issue, we conducted a participatory cover cropping trial in the Lower Rio Grande Valley (LRGV) region, encompassing four different farms and supplemented this experiment with a meta-analysis to answer our soil moisture and climate parameters and quantify the impact of cover crops on soil moisture levels. The findings revealed that …

Red Snapper Abundance, Growth, And Movement At Different Structural Configurations In The Rio Grande Valley Artificial Reef, Marybeth J. Weihbrecht

Theses and Dissertations

The Rio Grande Valley (RGV) artificial reef was built with the goal of providing habitat for reef fish at various life stages. This study used fish trapping to analyze red snapper and grey triggerfish size and abundance in the RGV reef. Mark-recapture of red snapper was utilized to determine growth, movement, and site fidelity within the reef. Nine configurations of patches consisting of varying combinations and densities of concrete pyramids and low-profile modules were surveyed, as well as additional sites of cinder block palettes and concrete railroad ties. Red snapper and triggerfish abundance per trap hour varied significantly by site …

Road Mitigation Structure And Road Effect Zone Impacts On Rodent Community Composition, Activity, And Predator-Prey Dynamics In South Texas, Adam F. Sanjar

Theses and Dissertations

The effects of road mortality mitigation structures on rodent activity and rodent community composition are not fully understood, both on the regional scale of south Texas and in the broader field of road ecology. This is primarily due to the low conservation priority of most rodent species and the difficulty of noninvasively surveying for rodents effectively. This thesis focused on characterizing how rodents were impacted by both roads and mitigation structures in south Texas, and if rodents are a significant factor to consider when studying the road ecology of rodent predators in south Texas, particularly ocelots, bobcats (Lynx rufus …

Study Of Population Dynamics Of Sugarcane Aphid (Melanaphis Sacchari) In Rio Grande Valley, Texas, Neetu Khanal

Theses and Dissertations

Chapter 1: This chapter incorporates detailed information about the biotype concept, aphids, their types and their biotypes, importance of studying insect biotypes and their role in mediating host plant defenses.

Chapter 2: This chapter explains in detail about the biology, biotypes, feeding behavior, damage, and economic loss caused due to sugarcane aphid infestation. This chapter further elaborates on the need for studying population level differences and justifies the objectives and significance of this research study.

Chapter 3: This chapter provides information about the comprehensive work done on three different populations of sugarcane aphid collected from three different locations in Rio …

Structural And Functional Insight Of Helicobacter Pylori Translation Initiation Factor If1 (Hpif1) In Protein Biosynthesis And Rational Design Of New Antimicrobial Candidates, Asif Shahriar

Theses and Dissertations

Helicobacter pylori (H. pylori) is a Gram-negative bacterium that colonizes the human gastric mucosa and is associated with peptic ulcer disease and gastric cancer. Bacterial protein synthesis is a fundamental metabolic process occurring in all bacteria and is a validated target of antibiotics; however, the precise structural mechanism of H. pylori protein biosynthesis remains unknown. Protein synthesis contains four stages, and translational initiation is the most important and highly regulated critical step, involving three initiation factors (IF1, IF2, IF3) and other key components. IF1 plays a vital role in regulating this step by binding to the 30S ribosomal subunit cooperatively …

Sweet Potato In The Lower Rio Grande Valley: Evaluating Performance Across Several Cultivars, Jon Dale

Theses and Dissertations

In Texas’ subtropical, semiarid Lower Rio Grande Valley (LRGV), citrus and sugarcane cultures have dominated specialty crop production for more than a half-century. However, the future of these high-dollar crops is becoming uncertain with increases in exotic pathogens, intensifying urbanization and the overarching complexities of both climate change and binational governance of Rio Grande Basin waters. For these reasons, the region’s specialty crop sector needs to be ready for alternatives that could benefit both market outlets and reduced input dependencies. Sweet potato (Ipomoea batatas), commercially grown in various similar climates worldwide with limited water resources, could be one …

Population Genetics Among Rhipicephalus Sanguineus Ticks In The Lower Rio Grande Valley, Bianca Liana Guerra

Theses and Dissertations

Rhipicephalus sanguineus is a common tick species in the lower Rio Grande Valley of both human and veterinary concern. Two lineages of R. sanguineus have been described across the United States known as the tropical and temperate lineage. Both lineages can be differentiated morphologically, genetically, biologically, and by vector competence. The species name for both lineages has not been well established therefore this thesis will utilize their widely used identification. Both lineages have been identified in Texas. While the distribution of these lineages has been well-defined in some regions across the world, recent studies have observed sympatric populations in certain …

Effect Of Elevated Temperature And Roundup Exposure On Oxidative Stress And Antioxidant Status In The American Oyster, Afsana Chowdhury

Theses and Dissertations

Aquatic organisms are frequently exposed to various environmental stressors. In this study, we observed the short-term (1-week) combined dose-dependent effect of Roundup, a glyphosate-based herbicide, and high temperature (30°C) on the morphology of gills and digestive glands, expression of heat shock protein-70 (HSP70), dinitrophenyl protein (DNP), nitrotyrosine protein (NTP), antioxidant enzymes such as catalase (CAT) and superoxidase dismutase (SOD) in tissues of American oyster (Crassostrea virginica). Histological analyses showed an increase in mucous production in the gills and digestive glands, hemocyte aggregation in the connective tissues as well as structural change of the lumen in the digestive glands …

Factors Influencing The Faunal Recolonization Of Restored Thornscrub Forest Habitats, Audrey J. Hicks

Theses and Dissertations

Tamaulipan thornscrub forests have high ecological and economic value, yet over 90% of these forests have been lost, primarily due to agriculture and urban expansion, and they remain threatened, making them a conservation hotspot. For decades, federal, state, NGO, and corporate entities have been acquiring land and actively or passively restoring these forests, but results have been mixed and seldom monitored. This study characterized and quantified faunal communities of restored thornscrub forest habitats in south Texas and examined the relationships between restored faunal communities and key site characteristics and environmental factors. We surveyed and analyzed mammals, birds, Lepidoptera, and herptiles …

Estimating The Functional Consequences Of Intra-Specific Trichome Variation Of Tomato, Solanum Lycopersicum On The Specialist Herbivore, Manduca Sexta, Satinderpal Kaur

Theses and Dissertations

Chapter 1: Plants have a wide array of defenses against herbivores and hence they must confer trade-offs between growth and defense related traits. By using Solanum as a model genus, the major plant defense fitness trade-off hypotheses are reviewed in this chapter along with their assumptions and examples.

Chapter 2: This chapter provides an overview of the enormous intra-specific diversity in trichome morphology in tomato, Solanum lycopersicum. Also, the trichome sub-types are analyzed for the variations in density and dimensions in 10 varieties of tomato by using desktop scanning electron microscope.

Chapter 3: This chapter examines the functional consequences …

Wildlife Road Mortality Patterns In South Texas And Survey Methodology Improvement, Bradley E. Beer

Theses and Dissertations

Mortalities of wildlife caused by collisions with vehicles along roads are increasing in prevalence, threatening the existence of various species and populations. A better understanding of how mortalities change in response to natural and anthropogenic variables and efficient methods of obtaining mortality data are essential to mitigating such mortalities. This thesis investigates several key elements to improving road mortality surveys in south Texas. First, it was found that road mortality survey counts did not change under a pandemic-related lockdown and that 2 mortality survey observers detect more mortalities than 1. Analysis of brown pelican groundings on Texas State Highway 48 …

The Molecular Evolution Of Insect Opsin Genes, Maria Jose Cardenas Muedano

Theses and Dissertations

Opsins are part of the superfamily of G-coupled receptor proteins and together with chromophores, are responsible for initiating the signal transduction cascade responsible for animal vision. Since opsins have a critical role on visual perception these genes are crucial for a myriad of adaptive traits and behaviors and should show diverse signs of natural selection at the molecular level. Understanding the evolution of opsins across the wide diversity of insect groups will allow us to better understand the evolutionary pressure on insect opsins and serve as a model for both other gene systems and other taxonomic groups of animals that …