Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
- Publication
- Publication Type
Articles 1 - 30 of 34
Full-Text Articles in Life Sciences
Impact Of The Degree Of Urbanization On Bird Abundance And Diversity, Gabrielle Doyle, Sheila Garcia, Sophie Kidd, Tra'dayja Smith
Impact Of The Degree Of Urbanization On Bird Abundance And Diversity, Gabrielle Doyle, Sheila Garcia, Sophie Kidd, Tra'dayja Smith
Fall Showcase for Research and Creative Inquiry
Bird diversity and abundance in Farmville, Virginia. Sampling twice a day, four days a week.
Effects Of Invasive Species On Post-Fire Ceanothus Spinosus Seedling Establishment, Nina Duchild, Frank W. Ewers, Stephen D. Davis
Effects Of Invasive Species On Post-Fire Ceanothus Spinosus Seedling Establishment, Nina Duchild, Frank W. Ewers, Stephen D. Davis
Featured Research
This study compared seedling establishment of the native chaparral species Ceanothus spinosus in two different burn sites at Pepperdine University following the Woolsey Fire of November 2018. One site was a low-density fuel site, and experienced a “cool burn,” and the other site was a high-density fuel site and experienced a “hot burn.” In the low-density fuel site, fire type-conversion had occurred, resulting in a dominance of exotic species. The high-density fuel site was populated by many native fire-following species and chaparral shrubs, exemplifying pristine post-fire conditions. Initially, I hypothesized that seedling success in the cool burn site would be …
Seedling And Resprout Survival Of Three Chaparral Species Following Woolsey Wildfire, Karagan L. Smith, Stephen D. Davis
Seedling And Resprout Survival Of Three Chaparral Species Following Woolsey Wildfire, Karagan L. Smith, Stephen D. Davis
Featured Research
Fire is a common natural disaster that effects Southern California. Combined with recent chronic drought, there has been an increase in the damage and frequency of these fires in recent years. Three chaparral species are common to the Pepperdine campus: Malosma laurina, Ceanothus spinosus, and Ceanothus megacarpus. The survival of these native species is essential because they are indicators for the changes that are occurring in our local ecosystem and provide further implications of how our ecosystem responds to natural disaster. Seedling recruitment and resprouting are mechanisms these chaparral species use to reestablish postfire. Postfire data have been recorded …
Post-Fire Soil Microbiome Recovery And Respiration In A Chaparral Ecosystem, Mari R. Irving, Stephen D. Davis
Post-Fire Soil Microbiome Recovery And Respiration In A Chaparral Ecosystem, Mari R. Irving, Stephen D. Davis
Featured Research
This study characterizes post-fire recovery of microbial and fungal populations adjacent to three keystone chaparral plant species affected by varying burn intensities via systematic measurement of soil respiration. The CO2 released from soil surrounding Ceanothus spinosus, Heteromeles arbutifolia and Malasma laurina affected by mild, severe or no heat during the Woolsey Fire of November 2018 were monitored and used as an indicator of microbial, fungal, and root activity. We hypothesized that soil which experienced less intense heat would exhibit higher rates of respiration based on preliminary data taken in March 2019. However, the opposite was observed from May through …
Photosynthetic Response Of Pentagramma Triangularis To Summer Desiccation, Brandon R. Grinovich, Stephen D. Davis
Photosynthetic Response Of Pentagramma Triangularis To Summer Desiccation, Brandon R. Grinovich, Stephen D. Davis
Featured Research
Ferns are thought to have been some of the first vascular plants to develop, perhaps on the order of 390 million years ago. Since then, ferns have speciated and developed innovative methods of survival especially in relation to water stress. Research conducted in 2016 by Helen Holmlund showed that eight California fern species fell into four primary classes of survival strategies, one of those being resurrection. Pentagramma triangularis is one of the resurrection-type ferns and is endemic to the western coast of the United States. As P. triangularis desiccates during the summer it enacts a physiological response by which it …
The Impact Of The Woolsey Fire On The Fungus Botryosphaeria Dothidea, Juan Arguijo
The Impact Of The Woolsey Fire On The Fungus Botryosphaeria Dothidea, Juan Arguijo
Featured Research
Southern California suffered a six-year drought in 2012 through 2018 during which the laurel sumac, Malosma laurina, experienced water stress and the fungus Botryosphaeria dothidea began to kill this plant, causing a massive dieback of this keystone chaparral species in the Santa Monica Mountains. Botryosphaeria is an opportunistic endophytic fungus that invades the xylem of woody type plants and waits till the plant starts to experience stress to proliferate. In November of 2018, the Woolsey fire burned up to 96,000 acres of vegetation. I ran tests at two sites on the Pepperdine University campus, the Baxter Ridge Site which …
Heteromeles Arbutifolia Associated Post-Fire Soil Microbiome Recovery And Respiration In A Chaparral Ecosystem, Gabrielle Boeger, Lauren Dedmon, Emma Thomsen, Alexander Soloniuk
Heteromeles Arbutifolia Associated Post-Fire Soil Microbiome Recovery And Respiration In A Chaparral Ecosystem, Gabrielle Boeger, Lauren Dedmon, Emma Thomsen, Alexander Soloniuk
Featured Research
The purpose of this post-Woolsey Fire project is to examine the relationship between soil respiration in areas of cool burns and hot burns relative to individuals of Heteromeles Arbutifolia. It was hypothesized that the soil subjected to a cooler burn would have greater respiration rates due to increased survival of microorganisms compared to a hotter burn. An Li-6800 CO2 Flux Chamber was used to collect measurements for several replicates. Significance was detected in the “Day 3” data, with the soil respiration higher at the cool burn site. Temperature and soil flux also varied directly. In the future experiments including increasingly …
Soil Respiration In Burned And Unburned Sites Of The Santa Monica Mountains, Sydney C. Jones, Micah S. Kim, Sierra H. Ball, Stephen D. Davis
Soil Respiration In Burned And Unburned Sites Of The Santa Monica Mountains, Sydney C. Jones, Micah S. Kim, Sierra H. Ball, Stephen D. Davis
Featured Research
Soil respiration (the flux of CO2 released by the soil due to microbial and root respiration and organic matter decomposition) can be affected by fire (Qu et al., 2009, Richards et al., 2012, Ryu et al., 2009). After the 2018 Woolsey Fire in the Santa Monica Mountains, we hypothesized that soil respiration would be greater in unburned soil than in burned soil. This is because fire can decrease soil nutrient concentration, which could decrease soil microbial concentration and also because fire could burn and kill soil microbes and roots. To test this relationship, we recorded soil respiration on three …
Physiological Performance Of Ceanothus Spinosus In Hot Burn And Cool Burn Sites, Rishi Gattu, Christian Hill, Chris Kulpaca
Physiological Performance Of Ceanothus Spinosus In Hot Burn And Cool Burn Sites, Rishi Gattu, Christian Hill, Chris Kulpaca
Featured Research
After the Woolsey Fire, many fire adapted plants will resprout. However, increased fire frequency has negatively impacted the reproduction of many native species, while enhancing the survivorship of many invasive species. We compared the physiological performance of Ceanothus spinosus resprouters in areas that burned hotter compared to areas that burned cooler. We hypothesized that resprouters in hotter burn sites would have better physiological performance than resprouters in cooler burn sites. The resprouters in hotter burn sites would have better performance because of decreased competition from invasive species. We measured physiological performance using a Li-Cor LI-6400, specifically photosynthesis, transpiration, and stomatal …
Comparative Fitness Of Post-Fire Transplant Stipa Pulchra And Wild Stipa Pulchra In Competition With Avena Fatua, Ashley Bonin, Madison Cook, Sara Head
Comparative Fitness Of Post-Fire Transplant Stipa Pulchra And Wild Stipa Pulchra In Competition With Avena Fatua, Ashley Bonin, Madison Cook, Sara Head
Featured Research
In the Spring Semesters of 2016 and 2017, research was conducted on the relative fitness of Stipa pulchra in the transplant garden on the Drescher campus at Pepperdine University. The first study in 2016 examined the fitness of Stipa pulchra and Avena fatua in the transplant and wild gardens after a five year drought in California. In the results of this experiment, the hypothesis was supported when observing that the wild S. pulchra depicted higher fitness that the transplant S. pulchra in areas of stomatal conductance, height, water potential, percent sun and dark-adapted fluorescence. The second study in 2017 investigated …
A Survey Of Post-Fire Chaparral Species’ Densities Using Point Quarter Sampling, Emma C. Stenz, Brandon R. Grinovich, Catherine H. William, Michael E. Gayed, Stephen D. Davis, Grace Palmer
A Survey Of Post-Fire Chaparral Species’ Densities Using Point Quarter Sampling, Emma C. Stenz, Brandon R. Grinovich, Catherine H. William, Michael E. Gayed, Stephen D. Davis, Grace Palmer
Featured Research
The purpose of this observational study was twofold: to add to the existing data regarding the plant species composition of the Pepperdine hillsides and to set in place a foundation for post-fire chaparral recovery studies that will ensue over the coming years through various programs and classes. The 2018 Woolsey Fire burned nearly all of the natural environment surrounding Pepperdine University and the greater Malibu region, so it is a matter of urgency to take this opportunity to learn more about how this natural environment of the chaparral responds to a catastrophic event like fire. We focused primarily on facultative …
Carbon Dioxide Flux Rate For Cold Burn And Hot Burn Sites, Sophia Cheong, Alexander G. Grissom, Grace K. Lank
Carbon Dioxide Flux Rate For Cold Burn And Hot Burn Sites, Sophia Cheong, Alexander G. Grissom, Grace K. Lank
Featured Research
This experiment seeks to further expand modern understanding of post-fire ecology via systematic measurement of soil respiration within areas burned by cool, mild flames and hot, intense flames caused by the recent Woolsey Fire. We theorized that within hot burned areas, soil respiration would be less than that of the cool burned areas because the microbe population in the hot burned areas would be affected far more than those subjected to a cool burn. By measuring soil respiration with our Li-6800 CO2 soil flux chamber at each of the according disc sites within hot and cold burned areas we …
Comparison Of Postfire Seedling Recruitment Of 2019 In Three Key Chaparral Species, Karagan Smith, Reid Furukawa, Brett Muramoto, Stephen D. Davis
Comparison Of Postfire Seedling Recruitment Of 2019 In Three Key Chaparral Species, Karagan Smith, Reid Furukawa, Brett Muramoto, Stephen D. Davis
Featured Research
Fire is a common natural disaster that sweeps through Southern California. Combined with periods of acute, and most recent, chronic drought, we have seen an increase in the damage and frequency of these fires in recent years. Three chaparral species are common to the Pepperdine campus: Malosma laurina, Ceanothus spinosus, and Ceanothus megacarpus. The survival of these three native species is essential because they serve as biomarkers for the changes that are occurring in our local ecosystem and provide further implications for how our ecosystem is responding to natural disaster. Seedling recruitment is a mechanism that is used by …
The Presence Of Fungal Pathogen, Botryosphaeria Dothidea, In Post-Fire Malosma Laurina Resprouts, Georgiana Gibson, Sarah Parker, Lauren Van Tress
The Presence Of Fungal Pathogen, Botryosphaeria Dothidea, In Post-Fire Malosma Laurina Resprouts, Georgiana Gibson, Sarah Parker, Lauren Van Tress
Featured Research
Botryosphaeria dothidea is an opportunistic fungal pathogen that infects plants, causing cankers to form on branches and stems, ultimately causing cell cavitation and embolism in the plant. Botyrosphaeria dothidea was found in much of the chaparral vegetation present in the Santa Monica Mountains prior to the November 2018 fire. In this study, we focused on the presence of Botryosphaeria dothidea in the chaparral plant Malosma laurina on Pepperdine University’s campus in 2 different populations: unburned and resprouts. We looked at whether the November 2018 fires had eliminated the pathogen from post-fire Malosma laurina resprouts, using the unburned Malosma laurina population …
Post-Fire Competition Between Native Ceanothus Spinosus And Exotic Grasses, Katarina Carter, Nina Duchild
Post-Fire Competition Between Native Ceanothus Spinosus And Exotic Grasses, Katarina Carter, Nina Duchild
Featured Research
In our experiment, we investigated the post-fire competition between native Ceanothus spinosus and exotic grasses in low and high-density fuel sites. We hypothesized that C. spinosus seedlings in the high-density fuel site would be larger and more numerous than seedlings in the low-density fuel site, due to differences in competition from exotics. Our results showed that there was no significant difference in seedling height of C. spinosus in the high-density fuel site (5.33 ± 0.55 cm) and in the low-density fuel site (4.31 ± 0.51 cm). There was also no significant difference in the average number of seedlings in the …
A Post-Fire Comparison Of Resprouts To Unburned Malosma Laurina Shrubs In The Santa Monica Mountains Of Southern California, Anthony Joseph Adducci Ii, Sierra Jo Smith, Dylan Jesse Waddill
A Post-Fire Comparison Of Resprouts To Unburned Malosma Laurina Shrubs In The Santa Monica Mountains Of Southern California, Anthony Joseph Adducci Ii, Sierra Jo Smith, Dylan Jesse Waddill
Featured Research
Fire is a cornerstone to Mediterranean ecosystems but increased droughts, climate change and human interference has caused a shift in fire frequency and severity. This experiment accessed the physiological performance of Malosma laurina resprouts in burned areas compared to mature Malosma laurina in unburned areas. Specifically, we hypothesized that the stomatal conductance, photosynthesis rate, and electron transport rate of the burned resprouts would all be higher than the unburned shrubs as there are more nutrients available in the soil post-fire and the resprouts have a larger root to stem ratio. Using the LI-6400 Portable Photosynthesis System, we measured the physiological …
Post Fire Seedling And Resprout Survival Of Melasma Laurina, Matthew Sturtevant, Gil So
Post Fire Seedling And Resprout Survival Of Melasma Laurina, Matthew Sturtevant, Gil So
Featured Research
For this research project we set out to see how seedling and resprout survival rate of melasma laurina would fare in the post fire environment found around pepperdine. The expected seedling survival was set to be 1% and the resprout survival was at 100%. From our field research we found that the the seedling survival was 41% and the resprout 57.3%. By using a T-test we had a p value < 0.001 for both data sets, this means that our data deviated greatly from our expected data and meant that we had to reject our hypothesis.
Nitrate Removal And Patterns Of Ph-Induced Flocculation In High-Lipid Producing Algae Ochromonas Danica, Abigail E. Armstrong, Timothy Gsell Dr.
Nitrate Removal And Patterns Of Ph-Induced Flocculation In High-Lipid Producing Algae Ochromonas Danica, Abigail E. Armstrong, Timothy Gsell Dr.
Research Days
Algae have grown in popularity as a source for biofuels as some algae species, like Ochromonas danica, can produce energy-rich lipids for biofuels while simultaneously removing nutrients from wastewater. As such, use of biologic systems to mitigate pollutants are an attractive method of pollution control. Given the unique metabolic properties of O. danica, this organism is a promising candidate organism for this purpose. This study seeks to characterize the basic metabolic parameters of these algae as well as their population behaviors with attention to their growth rates and nitrate removal at varying pH over time. To do this, live cultures …
Preservation Of Ozark Glades: Soil Inocula And Plant Additions Effect On Arbuscular Mycorrhizal Fungi, Srikavi Premnath
Preservation Of Ozark Glades: Soil Inocula And Plant Additions Effect On Arbuscular Mycorrhizal Fungi, Srikavi Premnath
Show Your Stripes Research and Creative Showcase
Soil microbial communities can play a major role in the structure of natural plant communities, and restoring the soil microbial content can be important in restoring the plant community in prairies. In 2014, an experiment was set up to test whether soil inoculation along with native plant additions (Schizachyrium scoparium and Rudbeckia missouriensis) produce a similar restoration effect among glades, rocky grasslands found in south central Missouri. The following six inoculation treatments were set up in three sites: live inocula soil from well-restored glade sites, sterilized glade soil as a control, inoculated S. scoparium, uninoculated S. scoparium, inoculated R. missouriensis, …
The Relationship Between Diet And Evolution In Primates, Tori Spencer
The Relationship Between Diet And Evolution In Primates, Tori Spencer
Show Your Stripes Research and Creative Showcase
This literature review investigates the evolutionary relationship between diet and primate physiology, using both human and non-human primates as evidence of past and present examples. Special attention is devoted to physiological factors shaped by diet that have and may still cause differences between primate groups. Diet has heritable markers and can predisposition individuals to change both physically and behaviorally. Diet in primates appears to play a role in the teeth placement, brain size, shape and chemistry, taste and olfactory sense, to name a few. This information can be used to identify future human features that may continue to evolve as …
Selecting Phycoremediators For Consortia, Tori Spencer
Selecting Phycoremediators For Consortia, Tori Spencer
Show Your Stripes Research and Creative Showcase
Bioremediation is the process by which organisms remove and transform toxic compounds in a contaminated source. This is a waste management technique currently used to clean up man-made contamination. Many organisms act as natural remediators; in the case of algae, they are called phycoremediators who perform phycoremediaton. The term algae encompasses a variety of taxonomic groups and their diversity is still being realized; there are over 44,000 named species of the 72,000 species that we have identified. Some estimates calculate that there are over 200,000 diatom species alone. This diversity continues to be difficult to organize, which is problematic for …
Imaging Fluorescent Proteins In Plant Cells: A 12-Week Research-Project Oriented Cell Molecular Biology Laboratory, Michael Grubb, Bridget Mbula
Imaging Fluorescent Proteins In Plant Cells: A 12-Week Research-Project Oriented Cell Molecular Biology Laboratory, Michael Grubb, Bridget Mbula
Show Your Stripes Research and Creative Showcase
When plants are attacked by pathogenic fungi, plants defend themselves by "chewing" the fungal cell wall. Chitin, a main component of the fungal cell wall, is released and recognized by the plant cells to activate the innate immune response in the whole plant. The objective of this study is to investigate the cellular localization of the proteins encoded by two chitin-induced genes, Annexin 1 (ANN1) and SNAP33, from the genetic model Arabidopsis thaliana. The full-length cDNA (excluding stop codon) of ANN1 and SNAP33 were amplified from cDNA template and cloned into a binary vector pMDC83 to form a translational fusion …
The Relationship Between Insect Visitors And Chemical Fragrance Composition Of Cypripedium Parviflorum Var. Pubescens In Central Virginia., Ruth Elkins
Student Scholar Showcase
Due to its rarity, little is known regarding which insects pollinate Cypripedium parviflorum var. pubescens, large yellow lady slipper orchids, and why they do so when offered no reward. Insect identification and fragrance composition data have been collected from two populations of large yellow lady slippers in Central Virginia for more than a decade. This research analyzed data in order to determine potential relationships between visiting insects and fragrance compositions of the orchid. The results of this research can be used to establish and protect populations of Cypripedium parviflorum var. pubescens.
Alpha Mangostin As A Chemoprotective Agent Via Activation Of The P53 Pathway For Breast Cancer, Vanessa Van Oost
Alpha Mangostin As A Chemoprotective Agent Via Activation Of The P53 Pathway For Breast Cancer, Vanessa Van Oost
Scholar Week 2016 - present
Breast carcinoma is the most frequently diagnosed cancer among women and causes over 400,000 deaths yearly worldwide. Current treatments such as chemotherapy are not selective for cancerous tissues but are destructive to normal tissues as well. This causes a range of side effects including pain, nausea, hair loss, weakness, and more. Inactivation of p53 is an almost universal mutation within human cancer cells. The ability to activate the p53 pathway which protects cells from tumor formation is lost in 50% of cancers. Due to the prevalence of this mutation, p53 is a uniquely valuable target for applied research. Alpha mangostin …
Comparative Methodology For Analyzing Nitric Oxide Production In Raw 264.7 Murine Macrophages In Response To Lipopolysaccharide Treatment, Cassandra Robertson
Comparative Methodology For Analyzing Nitric Oxide Production In Raw 264.7 Murine Macrophages In Response To Lipopolysaccharide Treatment, Cassandra Robertson
Student Scholar Showcase
The purpose of this experiment is to develop comparative methodology for analyzing RAW 264.7 murine macrophage responses to bacterial lipopolysaccharide (LPS). These results will yield two endpoints relative to nitric oxide production: nitrites in solution from the Greiss assay, and protein expression of inducible nitric oxide synthase (iNOS). The RAW 264.7 cell line is a standard culture model of macrophage activity and stimulation with LPS induces inflammatory reactions. This process has evolved to kill ingested pathogens and activate local immune responses, including the production of nitric oxide, synthesized by iNOS. RAW 264.7 cells are stimulated with LPS doses from 1 …
A Chemical In Filter Paper Interferes With Trail Following Behavior In The Termite Reticulitermes Hesperus (Banks), Kathryn Vest
A Chemical In Filter Paper Interferes With Trail Following Behavior In The Termite Reticulitermes Hesperus (Banks), Kathryn Vest
Student Scholar Showcase
Termites follow chemical trails. In previous experiments we dissolved and diluted chemicals in acetone to test if they elicited trail following. Each trail was a straight line across the arena drawn with 10 µl using a glass capillary (Microcaps). We noticed a minor but stable response to trails laid with pure acetone. The response could be caused by contaminated acetone or by a chemical in the filter paper (Watman #5) that lined our arena (petri dish, 10cm diameter). We could confirm that the termites respond to acetone alone. Soxkhlet extraction for 8 hours removed the signal from the filter paper. …
Co-Occurrence Of Manganese Oxidase Genes Indicates Lateral Transfer Between Classes Of Proteobacteria, Jacob Olichney
Co-Occurrence Of Manganese Oxidase Genes Indicates Lateral Transfer Between Classes Of Proteobacteria, Jacob Olichney
Student Scholar Showcase
Pseudomonas putida GB-1 is a model organism for the study of manganese oxidation in bacteria, however, the frequency of co-localization of multiple known and suspected manganese oxidizing proteins, as well as their occurrence between species, is unknown. Eight different genes isolated from known manganese oxidizing bacteria (MnxG, MopA, McoA, PputGB1_2552, PputGB1_2553, MoxA, MofA, and Bacillus MnxG) were tested individually using BioPython and BLAST (Basic Local Alignment Search Tool) on multiple genomic databases. BLAST searches had an expect value cutoff of 1e-50, limiting gene homologs to those with high sequence similarity. The abundance of homologous genes across classes of proteobacteria point …
Effect Of Environmental Conditions On Biomass Of Symplocarpus Foetidus, Christy Lemay
Effect Of Environmental Conditions On Biomass Of Symplocarpus Foetidus, Christy Lemay
Student Scholar Showcase
Symplocarpus foetidus (skunk cabbage) is an obligate wetland plant that occurs sporadically in wetlands throughout Virginia. Its life cycle is well studied with flowers budding in late January to early February through a process known as thermogenesis that heats the soil surrounding the plant. Pollination of fruits by flies and distribution of fruits/seeds through wildlife. Leaves appear in March with full growth above ground by early May. The leaves die back by July. Reproduction and distribution is sensitive to disturbance and environmental factors such as soil moisture, hydrology, and seed distribution. We collected environmental data in eight designated wetland plots …
The Role Of Plastic Debris Found In The Loggerhead Sea Turtle's Digestive Tract & How It Effects The Reproduction Survival Rate, Taylor Clements
The Role Of Plastic Debris Found In The Loggerhead Sea Turtle's Digestive Tract & How It Effects The Reproduction Survival Rate, Taylor Clements
Spring Showcase for Research and Creative Inquiry
No abstract provided.
Pregnancy In Zoo-Managed African Elephants (Loxodonta Africana): Investigating Possible Hormonal And Metabolic Indicators Of Successful And Unsuccessful Pregnancies., Chelsi Marolf
UNO Student Research and Creative Activity Fair
Female African elephants (Loxodanta africana) in zoos in the United States currently have high rates of ovarian acyclicity and if they do become pregnant, the calf is often lost before or during birth. This issue likely stems from various metabolic and reproductive factors, including obesity, advanced age, and stress. While this is a complicated problem, analyzing certain hormones related to reproduction and nutrition in elephants might reveal biological indicators for successful and unsuccessful pregnancies in African elephants. The goal of this study is to create a range of hormone levels throughout a typical successful pregnancy, and to compare …