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Characterizing The Roles Of Neutral Ceramidase In Cisplatin-Induced Kidney Injury., Sophia M. Sears Dec 2019

Characterizing The Roles Of Neutral Ceramidase In Cisplatin-Induced Kidney Injury., Sophia M. Sears

Electronic Theses and Dissertations

Cisplatin is a commonly used chemotherapeutic agent with a dose-limiting nephrotoxicity. 30% of patients given cisplatin develop acute kidney injury (AKI). AKI increases risk of chronic kidney disease (CKD) development and mortality. Patients that don’t develop clinical AKI are still at risk for long term declines in renal function. Currently, there are no FDA approved agents to treat or prevent cisplatin-induced kidney injury (CDDP-KI). In this study, we demonstrated that neutral ceramidase (nCDase) knockout provides protection from AKI in the high-dose model of CDDP-KI. However, in the repeated low dose cisplatin (RLDC) model of injury and we found nCDase knockout …


Visitor Characteristics, Attitudes, And Management Preferences Of The Bob Marshall Wilderness Complex, Samuel J. Rhodes Nov 2019

Visitor Characteristics, Attitudes, And Management Preferences Of The Bob Marshall Wilderness Complex, Samuel J. Rhodes

Electronic Theses and Dissertations

The Bob Marshall Wilderness Complex (BMWC) encompasses 3 federal wilderness areas and spans over 1.5 million acres of iconic mountains and valleys in northwestern Montana. Here visitors can find a plethora of recreation opportunity that give access to some of the most rugged country that can be found in the lower 48 states. However, managing wilderness areas comes with the challenge of both preserving the natural resources found within their borders and enabling opportunities for recreational experiences. Wilderness social scientists always have striven to determine the type of visitors coming to wilderness, and see what sorts of experiences they pursue. …


Genetic Diversity Of White-Tailed Deer Populations In Southwestern Pennsylvania And The Development Of A Forensics Panel, Melanie Quain Aug 2019

Genetic Diversity Of White-Tailed Deer Populations In Southwestern Pennsylvania And The Development Of A Forensics Panel, Melanie Quain

Electronic Theses and Dissertations

During the 20thcentury, white-tailed deer (Odocoileus virginianus) became scarce, prompting conservation efforts by hunters and wildlife managers with the goal to recover this species. Various strategies were implemented including reintroductions from areas that still had large deer populations, developing bag limits, seasonal restrictions, and habitat management. These efforts were highly successful across the United States.

Today, white-tailed deer are one of the most abundant and widely-distributed large-bodied mammals in North America. However, there are several important management concerns. In numerous states, including Pennsylvania, CWD negatively impacts deer populations and has become a major health concern. When …


Dual Inhibition Of The Pi3k/Akt And Mek5/Erk5 Pathways For The Treatment Of Breast Cancer, Thomas Douglas Wright Aug 2019

Dual Inhibition Of The Pi3k/Akt And Mek5/Erk5 Pathways For The Treatment Of Breast Cancer, Thomas Douglas Wright

Electronic Theses and Dissertations

Breast cancer is a heterogeneous disease state with several challenging frontiers. In particular, aberrations in the Phosphoinositide-3-kinase (PI3K) and Mitogen Activated Protein Kinase (MAPK) pathways have been linked to increased breast cancer proliferation and survival. It has been proposed that these survival characteristics are enhanced through compensatory signaling and crosstalk mechanisms. New evidence suggests that MEK5/ERK5, a member of the MAPK family, is a crucial component in the proliferation and survival of several aggressive cancers. We hypothesize that inhibiting both PI3K/Akt and MEK5/ERK5 pathways will decrease cell viability while maintaining limited collateral toxicity. In this study, we examined the effects …


Osmoregulation And Salinity Preference In Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Winyah Bay, Sc, Usa, Jessica Wingar Aug 2019

Osmoregulation And Salinity Preference In Juvenile Sandbar Sharks (Carcharhinus Plumbeus) In Winyah Bay, Sc, Usa, Jessica Wingar

Electronic Theses and Dissertations

Juvenile sandbar sharks (Carcharhinus plumbeus) have been caught in salinities ranging from 7 – 40. In Winyah Bay, a partially mixed estuary in Northeast SC, juvenile sandbar sharks tidally alternate between higher tides in middle bay and lower tides in lower bay. To assess salinity preference and duration in eight acoustically-tagged juvenile sandbar sharks in different salinities, acoustic receivers with salinity loggers were placed throughout Winyah Bay. Juvenile sandbar sharks were caught in salinities from 17.2 to 36.1 and acoustic detections were recorded from 11.5 to 24.7 by salinity loggers in middle bay. Smaller juvenile sandbar sharks used lower salinities, …


The Distinct Expressions Of Integrins Αdβ2 And Αmβ2 Differently Regulate Macrophage Migration In 3d Matrix In Vitro And In Tissue During Inflammation, Kui Cui Aug 2019

The Distinct Expressions Of Integrins Αdβ2 And Αmβ2 Differently Regulate Macrophage Migration In 3d Matrix In Vitro And In Tissue During Inflammation, Kui Cui

Electronic Theses and Dissertations

Chronic inflammation is an essential mechanism during the development of cardiovascular and metabolic diseases. The outcome of diseases depends on the balance between the migration and accumulation of macrophages in damaged tissues. Macrophage motility is highly regulated by adhesive receptors, integrins. Namely, intermediate expression of integrin supports macrophage migration, while a high integrin density inhibits it. Our studies are focused on evaluation of the contribution of related integrins αDβ2 and αMβ2 to macrophage migration and development of chronic inflammation.

We found that integrin αDβ2 is upregulated on M1-macrophages in vitro and …


Does Thermotolerance In Daphnia Depend On The Mitochondrial Function?, Rajib Hasan Aug 2019

Does Thermotolerance In Daphnia Depend On The Mitochondrial Function?, Rajib Hasan

Electronic Theses and Dissertations

Thermotolerance limit in aquatic organism is set by the ability to sustain aerobic scope to sudden temperature shifts. This study tested the genetic and plastic differences in thermotolerance of Daphnia that can be explained by the differences in the ability to retain mitochondrial integrity at high temperatures. Five genotypes with different biogeographic origins were acclimated to 18ᵒC and 25ᵒC. We developed a rhodamine 123 in-vivo assay to measure mitochondrial membrane potential and observed higher fluorescent in heat damaged tissues as the disruption of the mitochondrial membrane potential. Significant effects on temperature tolerance were observed with CCCP …


The Effects Of Branched Chained Amino Acid Supplementation On Acute Markers Of Fatigue And Performance, Joseph Walters Aug 2019

The Effects Of Branched Chained Amino Acid Supplementation On Acute Markers Of Fatigue And Performance, Joseph Walters

Electronic Theses and Dissertations

The purposes of this dissertation were to investigate the acute effects of branched-chain amino acids on psychological, physiological, and subsequent performance changes following high volume resistance training. The rationale for this study design was based on abrupt or contiguous training/ competitions that specific athletes encounter in a competitive season. This study design also sought to fill some gaps in the scientific literature concerning the efficacy of BCAAs for subjective fatigue in a resistance training paradigm. To address the purposes of this dissertation, a one-week study was conducted on resistance trained males, in which half of the subjects were randomly selected …


Plant Protein Prenylation In Environmental Responses And Protein Production., Parul Singh Aug 2019

Plant Protein Prenylation In Environmental Responses And Protein Production., Parul Singh

Electronic Theses and Dissertations

Lipid post-translational modifications enhance a protein’s interaction with membranes and other proteins. In this dissertation, I studied a recently identified Arabidopsis gene, PROTEIN PRENYLTRANSFERASE ALPHA SUBUNIT-LIKE (PPAL), by mapping a second-site mutation that rescues the original mutation phenotype and could be an additional factor involved in sugar homeostasis/sensing. I found that mutant phenotype associated with suppressor line was too weak and variable to consistently score, which resulted in not finding any linked markers. I also generated crosses between ppal-1 and ABA biosynthesis and signal transduction mutants to find any possible connection between these pathways and PPAL. By …


Exploring The Match Demands Of Division I Women’S Collegiate Soccer, Robert W. Sausaman Aug 2019

Exploring The Match Demands Of Division I Women’S Collegiate Soccer, Robert W. Sausaman

Electronic Theses and Dissertations

The purpose of this dissertation is to shed light on the physical demands of women’s soccer at the NCAA division I college level. Though research does exists describing the physical demands of women’s soccer, the vast majority seeks to explain the physical demands association with the professional and international level. This dissertation sought to: 1) examine the physical demands of NCAA division I women’s soccer and 2) observe changes in physical demands of two NCAA division I women’s soccer players over a four-year career using a case study approach.

Study 1 examined the physical demands of twenty-three athlete from a …


Comparison Of The Survival And Growth Of West Gulf Coastal Plain Pine In East Texas, Jamie Hooker Aug 2019

Comparison Of The Survival And Growth Of West Gulf Coastal Plain Pine In East Texas, Jamie Hooker

Electronic Theses and Dissertations

West Gulf Coastal Plain provenance loblolly (Pinus taeda L.), longleaf (Pinus palustris Mill.), shortleaf (Pinus echinata Mill.), and slash pines (Pinus elliottii Engelm.) were planted in East Texas to compare initial growth and survival. Containerized seedlings were planted in December 2015 on three study sites in Shelby, Houston, and Cherokee counties using a randomized complete block design. Seedlings were measured in January-February 2016 and again January-February 2017, January 2018, and January 2019. Three years after planting, survival was best (76.4%) in Houston County and was lowest in Cherokee County (26.4). Damage by Texas leafcutter ants (Atta …


The Effects Of Urbanization On Avian Seed Dispersal Success Of Toxicodendron Radicans (Anacardiaceae), Aiden M. Stanley Aug 2019

The Effects Of Urbanization On Avian Seed Dispersal Success Of Toxicodendron Radicans (Anacardiaceae), Aiden M. Stanley

Electronic Theses and Dissertations

Urbanization is increasing at a dramatic rate as the human population increases. While it is well-known that urbanization tends to decrease species diversity (i.e., biotic homogenization), it is not known how urbanization affects the frequency and efficiency of species interactions. Seed dispersal is a plant-animal interaction that depends on disperser feeding rate, disperser diversity, probability of seed dispersal and germination. How these factors are affected by urbanization however is unknown. In this study, we evaluate how urbanization alters these factors. Urban sites had 2x higher feeding rate and 3x higher number of disperser species. The probability of seed dispersal however …


The Influence Of Strength In Load-Velocity Relationships In The Back Squat, Thaddeus Light Aug 2019

The Influence Of Strength In Load-Velocity Relationships In The Back Squat, Thaddeus Light

Electronic Theses and Dissertations

Load-velocity relationships may vary between people of different strength levels and across different loads. The purpose of this dissertation was to investigate how external loads influence the velocity characteristics of the back squat exercise, and the influence of strength on these variables. Healthy male students with a history of resistance training completed repetitions at specified intensities of their estimated one-repetition maximum (1RM) until they reached 1RM. Back squat 3D motion analysis was captured using four Vicon T010 cameras (Vicon Motion Systems Ltd.; Oxford, UK) and Vicon Nexus 1.8.5 software. Data were transported into R custom coding statistical analysis software (version …


Barbell Trajectory And Kinematics During Two International Weightlifting Championships, Aaron J. Cunanan Aug 2019

Barbell Trajectory And Kinematics During Two International Weightlifting Championships, Aaron J. Cunanan

Electronic Theses and Dissertations

Several methods have been used in the scientific literature to study the weightlifting pull. Broadly, these methods are used to measure kinematic or kinetic variables exhibited by the lifter, the barbell, or the lifter-barbell system. However, there is an apparent disconnect between weightlifting research and coaching practice that may reduce the perceived benefits of technique analysis among coaches and present some challenges for coaches who seek to incorporate technique analysis into their coaching practice. Differences and trends in the technique of competitive weightlifting performances are apparent from the available literature. However, there are also gaps in the literature due to …


Visual Opsin Diversity In Anurans, Leah Perez Aug 2019

Visual Opsin Diversity In Anurans, Leah Perez

Electronic Theses and Dissertations

Among major vertebrate groups, anurans are understudied with regards to their visual systems and how they function. This study sampled North American anurans representing diverse evolutionary and life histories and which likely possess visual systems adapted to meet different ecological needs. Using standard molecular techniques, sequences were obtained for four opsins—the protein component of visual pigments—expressed in anuran retinas. Amino acid sequences of the genes RH1, LWS, SWS1, and SWS2 were compared across taxa to identify variable sites, as such variation can shift the spectral sensitivity of visual pigments and thus alter dim-light and color vision. Some of the amino …


Designing And Sample Size Calculation In Presence Of Heterogeneity In Biological Studies Involving High-Throughput Data., Sudhir Srivastava Aug 2019

Designing And Sample Size Calculation In Presence Of Heterogeneity In Biological Studies Involving High-Throughput Data., Sudhir Srivastava

Electronic Theses and Dissertations

The designing and determination of sample size are important for conducting high-throughput biological experiments such as proteomics experiments and RNA-Seq expression studies, thus leading to better understanding of complex mechanisms underlying various biological processes. The variations in the biological data or technical approaches to data collection lead to heterogeneity for the samples under study. We critically worked on the issues of technical and biological heterogeneity. The quantitative measurements based on liquid chromatography (LC) coupled with mass spectrometry (MS) often suffer from the problem of missing values (MVs) and data heterogeneity. We considered a proteomics data set generated from human kidney …


Transforming Moss P. Patens With Lignin Peroxidase Through Heterologous Protein Expression., Jesse Lee Rozsa Aug 2019

Transforming Moss P. Patens With Lignin Peroxidase Through Heterologous Protein Expression., Jesse Lee Rozsa

Electronic Theses and Dissertations

Lignin peroxidase is an enzyme secreted by white-rot fungi Phanerochaete chrysosporium. Our laboratory is attempting to produce several lignin degrading enzymes in our protein expression system that utilizes the moss, Physcomitrella patens. During our experiments we discovered that this particular species of fungus produces altered splicing variants that are not represented in the previously reported reference sequence. Despite several attempts to produce a positive transformant containing a desired transgene encoding; lignin peroxidase, production of the proper construct eluded our efforts, possibly due to toxic effects associated with lignin peroxidase expression. Our laboratory has created a stepping stone for other laboratories …


Characterization Of A More Clinically Relevant Human Leukemia Xenograft Model To Examine Perturbation Of Met/Sam Metabolism As A Novel Therapeutic Paradigm For Mll-R Leukemia In Vivo., Aditya Barve Aug 2019

Characterization Of A More Clinically Relevant Human Leukemia Xenograft Model To Examine Perturbation Of Met/Sam Metabolism As A Novel Therapeutic Paradigm For Mll-R Leukemia In Vivo., Aditya Barve

Electronic Theses and Dissertations

Acute myeloid leukemia (AML), is a heterogeneous clonal disorder characterized by an accumulation of malignant myeloid progenitors in the bone marrow (BM), hindering normal hematopoiesis. AML exhibits dramatic heterogeneity in terms of cytogenetics, morphology, and chemotherapeutic sensitivity. Therefore, the investigation of novel, efficacious AML therapeutics will require advanced preclinical in vivo model systems, capable of recapitulating patient specific disease heterogeneity, and induction chemotherapy outcomes. A major focus and eventual outcome of this work was the establishment and development of a more clinically relevant mouse xenograft model of patient AML, that efficiently harbors patient derived xenografts (PDXs), and unlike more prevalent …


Arachidin 3 Modulation Of Lipid Metabolism In Rotavirus Infections, Stormey Wisdom Jun 2019

Arachidin 3 Modulation Of Lipid Metabolism In Rotavirus Infections, Stormey Wisdom

Electronic Theses and Dissertations

Rotavirus (RV) can cause severe and deadly gastroenteritis in young children, infants, and immunocompromised individuals. Previous studies have shown that arachidin 3 (A3) inhibits RV replication, and that RV replication is dependent on the presence of lipids. This study investigated the alteration of lipid metabolism by A3 in RV infected HT29.f8 cells. A decrease in the RV regulation of lipid biosynthesis genes was observed with the addition of A3 using qRT-PCR. Also, immunofluorescent and histochemical staining for neutral fats, a major component of cellular lipid droplets, revealed an increased accumulation with both RV and RV+A3 when compared to no virus …


Molecular Characterization Of The Putative Nucleotide- Binding And Hydrolyzing Activities Of The Ellis Van Creveld (Evc) Protein, Giang Nguyen May 2019

Molecular Characterization Of The Putative Nucleotide- Binding And Hydrolyzing Activities Of The Ellis Van Creveld (Evc) Protein, Giang Nguyen

Electronic Theses and Dissertations

Ellis–van Creveld (EvC) syndrome is a rare autosomal recessive disorder that is characterized by short-limb dwarfism, extra fingers or toes, malformed teeth and nails, and congenital heart defects. Mutations in two genes, EVC and EVC2, which are located on chromosome 4, have been shown to be responsible for EvC syndrome. The protein products of these genes, EVC and EVC2 physically interact and together, they are tethered to the base of the primary cilium of cells. This multi-protein assembly positively regulates the Sonic and Indian hedgehog signaling pathways by promoting downstream processes after activation of the smoothened receptor (Smo), by the …


Generation Of Full-Length Wild-Type Gata4 Protein And Characterization Of Its Binding To Unc-45 Domains, Morgan Anderson May 2019

Generation Of Full-Length Wild-Type Gata4 Protein And Characterization Of Its Binding To Unc-45 Domains, Morgan Anderson

Electronic Theses and Dissertations

Striated muscle UNC-45 (SM UNC-45) protein acts as a chaperone for cardiac and skeletal muscle myosins; regulating their folding, assembly into thick filaments, interaction with other sarcomeric proteins, and degradation. GATA4 is an important transcription factor that regulates the expression of several cardiac muscle proteins, including myosin. A previous study demonstrated for the first time that SM UNC-45 (also known as UNC-45B) physically interacted with GATA4. The major revelation from this study is that SM UNC-45 has the potential to exert both short-term (protein level) and long-term (gene level) controls over myosin and therefore muscle structure and function. The aim …


Role Of The Glycerophosphocholine Acyltransferase, Gpc1, In Phosphatidylcholine (Pc) Biosynthesis And Remodeling In Saccharomyces Cerevisiae, Sanket Anaokar May 2019

Role Of The Glycerophosphocholine Acyltransferase, Gpc1, In Phosphatidylcholine (Pc) Biosynthesis And Remodeling In Saccharomyces Cerevisiae, Sanket Anaokar

Electronic Theses and Dissertations

Biomembranes are permeable barriers that enclose the cell and the intracellular organelles in a cell. The selective nature of these robust barriers acts as the first line of defense towards the harsh factors that can compromise cell survival. Biomembranes primarily consist of membrane lipids that are organized into layers to form a dynamic bilayer structure. The dynamic nature of the membrane requires the synchronized modulation of lipid composition through de novo synthesis, degradation, intracellular movement, and remodeling. Phospholipids are the major membrane lipid class, and phosphatidylcholine (PC) is the most abundant phospholipid in most eukaryotic biomembranes.

PC is primarily produced …


The Effects Of Constructed Wetlands On Metal Solubilization And Bioavailability In Passive Mine Remediation, Elizabeth Cochran May 2019

The Effects Of Constructed Wetlands On Metal Solubilization And Bioavailability In Passive Mine Remediation, Elizabeth Cochran

Electronic Theses and Dissertations

The legacy of coal mining in Appalachia has left many watersheds impacted by abandoned mine drainage. The drainage degrades streams, groundwater and habitats with acidity and toxic heavy metals. The Lowber Passive Remediation System has been in operation since 2004 to remediate high amounts of dissolved Fe, SO4, Al, and Mn. The site consists of six settling ponds and an extensive wetlands at the finish. This study investigated the resolubilization of Fe and Mn in the wetlands and the role of bacteria in resolubilization. During three seasons, field measurements of water quality and lab analysis of Fe, Mn, …


Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates May 2019

Effects Of Temperature On Microbial Parameters Associated With Decaying Plant Litter In A Stream Microcosm Experiment, Hunter David Pates

Electronic Theses and Dissertations

Increases in mean surface air temperature under climate-change predictions are expected to affect microbial activity, as well as carbon dynamics in aquatic ecosystems. I explored responses of litter-associated decomposers along temperature ranges typical of temperate streams in laboratory microcosms simulating stream conditions. The objectives of this study were to determine (1) whether the effects of temperature on stream leaf-associated microorganisms can be explained by the Metabolic Theory of Ecology (MTE); (2) if the effects of temperature are the same across temperatures commonly found in temperate streams; and (3) if there are differences in the magnitude of responses to temperature among …


Microplastics In The Digestive System Of The Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) In Winyah Bay, Sc, Elise Virginia Pullen May 2019

Microplastics In The Digestive System Of The Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae) In Winyah Bay, Sc, Elise Virginia Pullen

Electronic Theses and Dissertations

The digestive tracts and livers of adult male Atlantic sharpnose sharks (N=16), Rhizoprionodon terraenovae, from Winyah Bay, South Carolina were examined for ingested microplastics. R. terraenovae is a small, locally abundant, coastal mesopredatory elasmobranch belonging to the family Carcharhinidae. Microfibers comprised the largest categories of plastics (94% of the total), and were found in 100% of sharks examined. The number of micro- and other plastics ranged from 34 to 75 per individual and totaled 927. The majority of plastics (40%) were blue in coloration, and 55% were <1 mm in length. Microplastics were observed on both the interior and exterior of the organs examined, and three microfibers were embedded within the stomach lining, an observation not previously reported in marine vertebrates and one which represents a potential pathway for the translocation of ingested microplastics.


A Qualitative Case Study Of Student Persistence In A Bachelor Of Science In Forestry Program, Maxwell Holmes May 2019

A Qualitative Case Study Of Student Persistence In A Bachelor Of Science In Forestry Program, Maxwell Holmes

Electronic Theses and Dissertations

Educational leaders in forestry have been challenged to increase and diversify the pipeline of ‘society ready’ foresters. To meet these challenges, leaders must shift their focus to student retention. By understanding the factors that influence student engagement and persistence, these leaders will be better positioned to support students in forestry programs, thus positively impacting retention. This qualitative case study investigated student persistence of second-year forestry students in an undergraduate forestry program. The study was guided by Social Cognitive Theory and Social Capital Theory and explored the malleable psychosocial mechanisms of self-efficacy, sense of belonging, emotion, and well-being proposed by Kahu …


Comparison Of An Acute Bout Of Exercise To A Sugary Snack On Energy, Mood And Cognitive Performance, Erica Knowles May 2019

Comparison Of An Acute Bout Of Exercise To A Sugary Snack On Energy, Mood And Cognitive Performance, Erica Knowles

Electronic Theses and Dissertations

Low perceived energy and a decline in cognitive performance throughout the day are common issues, though exercise and food consumption are suggested to improve mood and cognition. The present study compares effects of acute exercise to consuming sugar on mood, energy, and cognitive performance. Subjects underwent blood glucose testing, completed an Abbreviated Profile of Mood States Questionnaire, and Automated Operation Span (OSPAN) and Digit Span tests to measure memory and attention. On two separate days subjects consumed candy or walked on a treadmill for 10 minutes, then measurements were repeated at 30-min, 60-min, and 120-min post. Two-way ANOVA over time …


Preference For Odor-Taste Mixtures Is Dependent On Previous Experience., Kelsey Allison Mcqueen May 2019

Preference For Odor-Taste Mixtures Is Dependent On Previous Experience., Kelsey Allison Mcqueen

Electronic Theses and Dissertations

The perception of flavors occurs when a tastant is simultaneously detected and associated with an odorant (i.e., odor-taste mixture). Sampling an odor and taste together results in a congruent odor-taste mixture. Mixing an odor and taste from different congruent odor-taste pairs results in incongruent odor-taste mixtures. Creation of a flavor percept requires sampling a novel chemosensory stimulus; however, mammals exhibit robust neophobic behavior when presented with new chemosensory stimuli. To determine preferences for novel odorants and experienced odor-taste mixtures, we employ a two-bottle brief-access preference task where two chemosensory stimuli are presented simultaneously. We found that rats show a preference …


Eyes In The Field, A Seat At The Table, A Voice At The Ranch : A Study On Optimal Farm Labor Conditions., Christine Wiggins-Romesburg May 2019

Eyes In The Field, A Seat At The Table, A Voice At The Ranch : A Study On Optimal Farm Labor Conditions., Christine Wiggins-Romesburg

Electronic Theses and Dissertations

The field of human resource development has twin obligations to promote the performance of organizations and the satisfaction and welfare of all workers. Nevertheless, agriculture appears to be an understudied industry in the field, despite this obligation and the potential for suffering experienced by workers performing crop work. This case study sought to understand the process through which a single agricultural operation fosters optimal conditions for workers engaged in labor-intensive crop production. This study found employees experienced better treatment compared to other agricultural operations, and that conditions were rich in both intrinsic and extrinsic factors. Intrinsic factors were marked by …


Pine, Aphids, And Parasitoid Wasps: Patterns Of Cospeciation And Host Switches In A Tri-Trophic System, Amber Bass May 2019

Pine, Aphids, And Parasitoid Wasps: Patterns Of Cospeciation And Host Switches In A Tri-Trophic System, Amber Bass

Electronic Theses and Dissertations

Ecological interactions may drive speciation events, and the processes that drive these speciation events can leave behind patterns in the phylogenies of interacting taxa. These patterns have been studied extensively in herbivores and host plants, as well as parasites and their hosts, but rarely in tri-trophic systems. Here, we examine three closely related groups of interacting taxa, including parasitoid wasps (Pauesia), aphid herbivores (Cinara), and pine trees (Pinus) to determine if the patterns between each interacting taxa indicate that cospeciation or host switches are more dominant. We create phylogenies of Cinara and Pauesia in the southeastern United States using ddRADseq …