Life Sciences Commons^™

Acute And Chronic Rejection: Compartmentalization And Kinetics Ff Counterbalancing Signals In Cardiac Transplants, Anupurna Kaul

ETD Archive

Heart disease is the major cause of mortality in the United States and other parts of the world. Heart transplantation is the treatment of choice for patients with end stage heart failure. However, transplanted organs fail due to either acute or chronic rejection. This acute and chronic rejection impacts distinct compartments of cardiac allografts. Acute rejection is characterized by infiltration of mononuclear cells whereas chronic rejection is characterized by progressive narrowing of coronary arteries. In a minor histoincompatibility mismatch mouse model we found hearts transplanted from male to female C57BL/6 mice undergo an acute rejection with diffuse interstitial infiltrates at …

Trypanosoma Brucei Telomere Functions In Antigenic Variation, Unnati M. Pandya

ETD Archive

Trypanosoma brucei is a protozoan parasite that causes sleeping sickness in humans and Nagana in cattle. They evade the host's immune defense by periodically switching their major surface antigen, variant surface glycoprotein (VSG), a phenomenon termed antigenic variation. Inside its mammalian host, bloodstream form (BF) T. brucei monoallelically expresses its major surface molecule VSG from the VSG Expression Sites (ESs) located at subtelomeric loci. Monoallelic VSG expression ensures effective antigenic variation and maximizes the efficiency of T. brucei pathogenesis. In the mid-gut of its insect host (tsetse), procyclic form (PF) T. brucei expresses procyclins as the major surface molecules and …

Study Of Role Of Ribosomal Protein L13a In Resolving Inflammation, Darshana Poddar

ETD Archive

Inflammation is an obligatory attempt of the host immune system to protect the body against infection. However, unregulated synthesis of pro-inflammatory products can have detrimental effects. Though mechanisms which contribute to inflammation are well appreciated, those that resolve inflammation are poorly understood. Therefore, understanding the molecular basis of such pathways will provide an entirely novel approach to treat and prevent inflammatory diseases. Transcript-selective translational control can regulate the expression of a set of inflammatory genes. We have identified one such mechanism in a novel animal model which relies on the abrogation of ribosomal protein L13a-dependent translational silencing by creating macrophage-specific …

Role Of Mtorc1 And Autophagy In The Regulation Of Chemoresistance In Leukemic B-Cells, Arishya Sharma

ETD Archive

Deregulated mTORC1 contributes to tumorigenesis and chemoresistance. However, mTORC1-specific inhibitors (rapalogs) show modest efficacy in the clinic, as they unleash the feedback inhibition on upstream, prosurvival pathways. An alternative approach is to target downstream functions of mTORC1. We investigated acquired resistance to fludarabine (Flu), a purine analog, active agent for chronic lymphocytic leukemia (CLL). Elevated phospho-p70S6k (T389), an mTORC1 activation marker, predicted Flu resistance in a panel of B-cell tumor lines, and primary CLL cells. However, the rapalogs induced moderate cell death in Flu-resistant (FluR) and primary CLL cells. Activation of oncogenic pathways, including mTORC1, induces profound metabolic reprogramming to …

Receptor Of Advanced Glycation Endproducts (Rage) Is Positively Correlated With Tumor Necrosis Factor-Α In Adolescents With Obesity, Tasnim Rahman, Daniel H. Conrad, Anshu Gupta

UROP Posters

Introduction: Obesity in childhood is associated with an increased prevalence of diabetes and other traditional cardiometabolic risk factors, suggesting an epidemic of premature cardiovascular disease among today’s youth. Glycotoxins, known as advanced glycationend products (AGE’s), activating via the membrane-bound receptors (mRAGE), have been implicated in the pathophysiology of inflammation, (increased tumor necrosis factor-α [TNF-α ]), insulin resistance and vascular dysfunction in adults, but the role of RAGE in the early stages of metabolic disorders is unknown. In this study, we assessed relationship of cardiometabolicrisk factors, mRNA expression of TNF-α and RAGE in peripheral monocytes in adolescents with obesity.

Methods: Thirty …

Drought-Induced Mortality In Malosma Iaurina And Ceanothus Megacarpus In Response To California's Changing Climate, Stefano Berrios, Stefani Francisco, Olivia Kim

Featured Research

The hypothesis of this research and experiment is that Malosma laurina is better adapted to drought than Ceanothus megacarpus due to its adaptation of deep roots. This addressed the question of which plants are better adapted to drought and by which adaptations are they superior. We decided to choose these two types of chaparral due to their differences in adaptations: Malosma laurina having deep roots and Ceanothus megacarpus utilizing cavitation resistance. Our method of investigation was to study the findings of scientific journal articles and to conduct our own experiment involving the mortality of Malosma laurina on the Pepperdine University …

Comparison Of Downstream Cell Survival Responses In Huvecs And Hlecs During Vegf Signaling, Haley M. Smith, Thomas Vandergon

Featured Research

Angiogenesis and lymphangiogenesis are vital processes that allow the formation of new blood and lymph vessels from existing vessels to bring oxygen and vital nutrients to the body. These processes occur through Vascular Endothelial Growth Factor (VEGF) signaling to vascular endothelial cells where they bind to cell surface receptors. There are a variety of responses to these signals including cell proliferation, migration and survival. In this study Human Umbilical Vascular Endothelial Cells (HUVECs) and Human Lymphatic Endothelial Cells (HLECs) were stressed with Tunicamycin and supplemented with various VEGF signals to examine how cell survival pathways might respond during VEGF signaling. …

Reduced Ability Of Drought-Effected Plants To Assimilate Carbon Dioxide, Adrian Alvarado, Francisco De Mendiola, Julia Namkoong, Yunni Zhai

Featured Research

As a group, we hypothesized that plants affected by the drought will absorb less CO2 compared to those that are irrigated regularly by Pepperdine University. In order to test this out we used the Carbon Dioxide CO2 transmitter which analyzed the carbon dioxide levels and conduction of three leaves that are under the drought and three leaves that are fully irrigated. The results were outstanding. As we hypothesized, the irrigated leaves had significantly higher CO2 and photosynthesis values than the leaves that were in the drought. The results are clearly reflected in the data, and consistent with the initial hypothesis. …

What You Can Do About The Negative Effects Of Methane, Jb Maza, Laurel Rodewald, Ashley Thurmond

Featured Research

Our central objective was to investigate the apparent rise in methane emissions and whether or not they are having a negative effect on the environment. By themselves, methane emissions are natural and self-regulating (and thus do not cause damage to the atmosphere), but our thesis is that a build up of methane emissions as a result of increased human activity/negligence poses a threat to the environment, and needs to be addressed in the quest to live sustainably. In our research, we chose to focus specifically on one source of methane emissions: permafrost, both because there is a significant amount of …

Initial Post-Fire Resprout Success Of Q. Agrifolia, J. Californica, And P. Racemosa In Sycamore Canyon, Frida Morales, Sawyer Mcgale, Drew Bowers, Zahra Madraswala, Michael Mori

Featured Research

Resprouting after fire and during a drought can be one of the greatest challenges a plant faces. This phenomena was observed and recorded in three different species of trees: P. racemosa, Q. agrifolia, and J. californica, all located in the Sycamore Canyon study site in Pt. Mugu State Park. P. racemosa was hypothesized to initially be the most successful post fire resprouter. The rationale for this is that the DBH and deciduous factor would cause the tree's vascular system to survive and possess usable starches to power resprouting. The data was analyzed and found to support the hypothesis.

Community Structure And Differential Mortality Of Chaparral During Extreme Drought, Keb Doak, Allison Hubbard, Alawna Jamison

Featured Research

We have set out to find, in extreme drought, which species of chaparral are dominant and why they are dominating. We thought that the indicator species of chaparral, Adenostoma fasciculatum, would have highest relative density, relative frequency, and dominance in our research area. Additionally, plants with higher water potential values would have lower percentages of mortality. Chaparral with stronger ability to fluoresce (higher Fv/Fm value) would have lower mortality percentages due to their ability to dissipate excess energy, and therefore reduce water loss. By analyzing our vegetation area using point-quarter sampling system, we were able to record data that show …

Effects Of Personal Gardens On The Reduction Of Atmospheric Co2 And Climate Change, Jacqueline N. Brody, Paige L. Elson, Brittany V. New

Featured Research

This study aims to explore the long-term benefits of home gardening if every student at Pepperdine were to hypothetically sustain their own home garden in the state of California and the effect that this would have on state carbon absorption as a means of decreasing atmospheric CO2 and reducing further climate change.

Measuring Performance Of A Weedy Species (Nicotania Glauca) Vs. A Native Species (Venegasia Carpesioides) On The Pepperdine Campus, Emily J. Blair, Zach G. Coffman, Celina Y. Jones

Featured Research

This study investigated four different mechanisms of growth performance of a native chaparral species, Venegasia carpesioides, and a weedy species, Nicotiana glauca. The research group hypothesized that one or more of the following variables would be higher for the weedy species than the native species: photosynthetic rate, conductance, fluorescence, and electron transport rate (ETR). This hypothesis was formulated in order to provide a plausible explanation for why weedy species often outcompete native species when grown in proximity to each other, especially in a chaparral environment experiencing drought conditions. This hypothesis was tested by obtaining two groups of each species and …

Water Analysis Of The Malibu Lagoon And Pacific Ocean, Emily E. K. Kelly, Jillian S. Unruh, Maxwell K. Gamboa

Featured Research

This experiment tested the waters of the Malibu Lagoon and the Pacific ocean to compare levels of E.coli. We hypothesized that greater amount of E.coli would be present in the waters of the Malibu Lagoon. Because of the runoff and pollution existing in the lagoon, we predicted that higher levels of this bacteria would be found there. This study is significant because many organisms living in these waters can be negatively effected by large levels of E.coli. We used the most probable number method to determine the amounts of bacteria. A collection of samples from three testing sites in both …

Climate Change And Drought In California, Jake Szarzynski, Wei Zhang, Brennan Tatem

Featured Research

we believe that there is a correlation between the increasing frequency and duration of droughts in California and climate change. The first step to solving any problem, such as a drought, is to identify the cause of the problem. As a result of the research conducted, we can determine that it is possible that climate change is a leading cause to droughts. We hope that by providing evidence that climate change is causing droughts, people will become aware that climate change does have negative results that we experience on a daily basis. We used several different scholarly resources when conducting …

Coreopsis Gigantea And Ice Plant Relationship On Point Dume, Lizzie Fichtner, Mccartney Ruff, Sean Hanson

Featured Research

This study looks to determine the affects of the non-native ice plant on the native Coreopsis gigantea located at Point Dume in Malibu, California. After examining the size of the Coreopsis we were able to identify that they were smaller in height when growing next to the ice plant and greater height when farther away. We concluded that the Coreopsis does survive next to the ice plant, however its growth is restricted. Through our research we discovered many factors that could attribute to the growth difference, yet further research is necessary to decipher the main one.

Post-Fire Recovery Of Juglans Californica In Sycamore Canyon: Gas Exchange Performance Of Unburned Mature And Burned Epicormic And Basal Resprouts, Taylor Stucky, Gabby Gurule-Small

Featured Research

Sycamore Canyon experienced a fire during April of 2013. This allowed for the comparison of burned and unburned individuals in the area. Based on its resprouting types and abundance in the area, Juglans californica made for a good test species. A total of eighteen individuals were tagged and used with a LiCor6400-XT to find fluorescence, Jmax, Vcmax, TPU, gm, photosynthesis, and conductance. Leaf samples were sent to California State University, Bakersfield for Nitrogen analysis to obtain PPNUE and percent nitrogen (with specific leaf area). These data were compared between unburned mature, and burned basal and epicormic resprouts. ANOVA testing established …

Seedling Survival After Novel Drought-Induced Germination In Ceanothus Megacarpus, Amanda M. Burns

Featured Research

As California is experiencing what is believed to be the worst drought in 500 years, monitoring the change of vegetation is of utmost importance. This spring we observed novel germination of Big Pod Ceanothus seedlings (Ceanothus megacarpus). Germination was novel in that seeds typically require a fire heat cue but in this particular case, germination was likely due to excessive soil temperatures resulting from drought-induced canopy reduction. This is a phenomenon not well known to science as Ceanothus megacarpus seedlings are typically not found between fire events. We believe this results from increased soil temperatures due to greater openings in …

Assessment Of P38 And Extracellular Signal-Regulated Kinase (Erk) In Regulating Apoptosis During Low And High Er Stress, Zachary G. Coffman

Featured Research

The endoplasmic reticulum (ER) is an important organelle within the cell that has many functions including protein folding. When the protein folding capabilities of the ER are compromised ER stress occurs. Extracellular signal-regulated kinases (ERKs) and p38 are MAP kinases that are induced as a result of ER stress. ERK is a protein that has been associated with cell proliferation and survival while p38 is a protein that has been associated with apoptosis, which is programmed cell death. The objective of this study was to measure ERK and p38 induction over time during low and high ER stress. Another objective …

Elevation’S Effect On Malosma Laurinais Leaf Size, Callyn E. Shelley, Nathan R. Gehring

Featured Research

Our hypothesis was that the average leaf size of Malosma laurinais would be different at high and low elevations due to the variance in temperature and solar radiation. This is especially relevant considering the severe drought conditions of California. Testing the factors of growth for chaparral may help ecologists to better understand how the plants cope with abnormalities in the ecosystem. Our study examined variance in Malosma laurinais leaf length, width, area, curvature, and thickness at high elevation (610 meters to 629 meters) and low elevation (27 meters to 53 meters) located along Sycamore Canyon. Differences were only significant in …

Flow-Induced Dilation Of Skeletal Muscle Feed Arteries: Relevance To Exercise Hyperemia, Brittni M. Moore, Jeffrey L. Jasperse

Featured Research

During exercise, an increase in blood flow to working skeletal muscle is accomplished by dilation of arteries and arterioles supplying the muscle. Arterioles, located within contracting muscle, are exposed to dilatory metabolites released by the muscle; however, the mechanism by which feed arteries, located external to the muscle, dilate is still unknown.

One potential mechanism for feed artery dilation is flow-induced dilation, occurring when arteries dilate in response to increased vascular wall shear stress. Shear stress is the frictional force between blood and the arterial wall, which increases when blood flow velocity increases. Data from previous in vitro experiments (8) …

Foliar Water Uptake And Resurrection: Mechanisms Of Drought Tolerance In Eight Species Of Ferns In The Santa Monica Mountains, Victoria M. Lekson

Featured Research

In a region where drought is severe, ecological surveys provide insight into the adaptations of organisms living on the edge of survival. In this study, the mechanisms of drought tolerance for eight species of ferns in the Santa Monica Mountains were assessed with a focus on foliar water uptake and resurrection strategies. We find that species are significantly different (P < 0.001) in their ability to absorb water through leaves (assessed gravimetrically) and correlate this to minimum seasonal water potential and hydrophobicity of leaf surfaces. Secondly, we irrigated Pentagramma triangularis in the field and tracked chloroplast recovery. We found possible evidence of embolism reversal. Taken together, this study explored the methods of survival of the most ancient family of vascular plants.

Evaluation Of The Three-Dimensional Patterns And Ecological Impacts Of The Invasive Old World Climbing Fern (Lygodium Microphyllum), Alexis Maldonado

Electronic Theses and Dissertations

Invasion by non-native species has had significant ecological and economic impacts on a global scale. In the state of Florida, Old World climbing fern (Lygodium microphyllum) is an invasive plant listed by FLEPPC as a category one invader with significant ecological impacts that threaten native plant diversity. This species relies on existing vegetative structures for support to climb into the forest canopy and forms dense mats that cover tree crowns. This subsequently affects the resources available to other species present. Quantifying the structural changes due to the presence of this species has proved logistically difficult, especially on a large spatial …

Approaches To Restoration: Assessing The Roles Of Structure And Function In Saltmarsh Restoration In Light Of Climate Change, Abby O. Pearson Ms

All Student Scholarship

The aim of this thesis is to review the current goals and methods for salt marsh restoration, to question how those goals and methods may change in light of global change, and to present a case study that offers a look at the kinds of information that can be gleaned by studying both structure and functionality in restoration.

An Avian Survey Conducted At Five Water Sources Within The Northern Chihuahuan Desert On Indio Mountains Research Station, Texas, Geoffrey Hugh Wiseman

Open Access Theses & Dissertations

The objective of this study was to conduct an avian survey of five water sources (four ephemeral former cattle tanks and one perennial spring), determine how many species inhabit or use Indio Mountains Research Station, and show a hierarchal similarity between the survey sites. This survey was conducted in a Chihuahuan Desert scrub landscape on Indio Mountains Research Station (IMRS) in Hudspeth County, Texas. There have been no previous formal studies of the avifauna at IMRS. All species accounts or sightings have been from casual sightings.

Eighty-five avian species were recorded during this project bringing the total of avian species …

Effect Of Increased Temperature And Decreased Food Quality On Metabolism And Growth Of An Algivorous Cichlid, Tropheus Duboisi And Effect Of Food Habit On The Field Metabolism Of African Cichlids., Lesley Yu-Jung Kim

Browse all Theses and Dissertations

The metabolic rate of an organism is influenced by mass, temperature, and diet. Climate change is anticipated to increase ambient temperatures of aquatic systems and decrease the quality of food available to algivorous fish. We conducted a lab experiment and a field study to quantify the influence that temperature and diet have on standard and field metabolic rate of cichlids from Lake Tanganyika. The lab experiment demonstrated the effects of increased temperature and decreased food quality on the relative growth rate (RGR) and standard metabolic rate of an algivorous cichlid, Tropheus duboisi. We found that in all temperature treatments fish …

Instructional Scientific Humor In The Secondary Classroom, Francine Wizner

Legacy Theses & Dissertations (2009 - 2024)

This study is an examination of the manner in which educators employ scientific content humor and how that humor is perceived by their students. Content humor is a useful strategy in drawing the attention of students and improving their receptivity toward scientific information. It is also a useful tool in combating the growing distractions of the electronic classroom. Previous studies have found that humor has a positive effect on knowledge, memory, and understanding. However, few studies have been conducted below the undergraduate level and mainly quantitative measures of student recall have been used to measure learning. This study employed multiple …

Genetic Stock Identification And Migration In Black Sea Bass (Centropristis Striata) Along The Western Atlantic Coast And Gulf Of Mexico, Justin Francis Lewandowski

Theses and Dissertations

The black sea bass, Centropristis striata, is a member of the family Serranidae that is commercially important throughout its range, which extends throughout the western Atlantic (from Cape Cod, Massachusetts to Cape Canaveral, Florida) and Gulf of Mexico (from Mobile Bay, Alabama to Tampa Bay, Florida). There are two known subspecies, C. striata striata in the Atlantic and C. striata melana in the Gulf, and through behavioral and morphological evidence two separate stocks are managed in the Atlantic, north and south of Cape Hatteras, NC. Recent genetic studies on mitochondrial DNA (mtDNA) have supported this. To further investigate the relationships …

Full Issue: Volume 8, Number 1

The Science Journal of the Lander College of Arts and Sciences

No abstract provided.

Origins Of The Classical Gene Concept, 1900–1950: Genetics, Mechanistic, Philosophy, And The Capitalization Of Agriculture, Garland E. Allen

Biology Faculty Research

In the period of “classical genetics” (roughly 1915–1950), the common view of the gene was mechanistic—that is, genes were seen as individual, atomistic units, as material components of the chromosomes. Although it was recognized early on that genes could interact and influence each other’s expression, they were still regarded as individually functioning units, much like the chemists’ atoms or molecules. Although geneticists in particular knew the story was more complex, the atomistic gene remained the central view for a variety of reasons. It fit the growing philosophy of mechanistic materialism in the life sciences, as biologists tried to make their …