Life Sciences Commons^™

The Rate Of Fungal Pathogen Growth (Botryosphaeria Dothidea) 
In Stems Of The Chaparral Shrub Rhus Integrifolia, Jayla D. Simmons, Edward J. Ayala, Kamara J. Satcher, Stephen D. Davis, Karagan L. Smith, Talia A. Cao

Featured Research

The fungus Botryosphaeria dothidea will grow between one to five millimeters after a week on the chaparral species Rhus integrifolia. To test this, we inoculated six individual shrub located behind the greenhouse on Campus Walk Road . On each shrub we selected two branches, receiving adequate and equal sunlight and inoculated one branch with the fungus B. dothidea and the other with a plain gel in order to compare the growth with a control group. The data we collected at the end of the one week period was similar to our initial hypothesis. The shortest growth was on the …

Post-Drought Recovery In The Chaparral Shrub Ceanothus Spinosus, Katie C. Lindley, Kylie N. Smith, Nina R. Duchild, Stephen D. Davis, Karagan L. Smith, Talia A. Cao

Featured Research

This study investigated the abilities of Ceanothus spinosus, or greenbark ceanothus, to recover after a historic drought. This plant is one of the hardiest in the Santa Monica Mountains, providing soil stabilization and nutrients to other organisms in the ecosystem. In a previous investigation done during the drought, it was found that C. spinosus subjects growing in their natural habitat experienced significant dieback, with predawn water potentials falling as low as -7 MPa and native embolisms at an average of 47.17% (Ross et al., 2016). Other parameters tested were stomatal conductance, photosynthetic rate, and chlorophyll fluorescence. Compared to the …

Comparison Of Photosynthesis Among Three Chaparral Species In The Family Anacardiaceae, Catelyn T. Price, Sarah A. Holmes, Brandon T. Harris, Stephen D. Davis, Karagan L. Smith, Talia A. Cao

Featured Research

Recent argumentative data showed a lack of niche differentiation amongst three Banksia species in Australia conducted by Lamont and Bergl, and the Anacardiaceae family in the native chaparral of the Santa Monica Mountains are supposed to be significantly similar¹. Because of this we wanted to test if there would be a significant difference between the stomatal conductance, photosynthesis, and water potential in samples of the Rhus ovata, Rhus integrifolia, and Malosma laurina (Rhus laurina) species. We tested this idea by collecting the stomatal conductance and photosynthetic rates of each plant species in the same general location with …

Testing For The Presence Of Botryosphaeria Dothidea In Ceanothus Spinosus, Brandon R. Grinovich, Chelsea N. Puncochar, Katarina L. Carter, Stephen D. Davis, Rodney L. Honeycutt, Talia A. Cao, Karagan L. Smith

Featured Research

Botryosphaeria dothidea is an opportunistic fungus found in some of the cavitated branches of the vegetation in the Santa Monica Mountains. In this study, we focused on finding the presence of Botryosphaeria dothidea in Ceanothus spinosus located on Pepperdine University’s campus. We wanted to test this hypothesis because we observed a large amount of dieback in the Ceanothus spinosus population and wanted to identify a possible contributor. Because of the large number of cavitated branches the Ceanothus spinosus contained, we hypothesized they contained fungus. To test this, we took twenty samples of twenty different Ceanothus spinosus, isolated the fungus …

Frontline Experiences From Changing Fisheries Bycatch Paradigms, David Kerstetter

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

No abstract provided.

A Comparison Of Water Potential, Photosynthetic Rate, Electron Transport Rate, And Stomatal Conductance Between Native Malosma Laurina And Exotic Schinus Molle, Karagan L. Smith, Agatha C. Heng, Viridiana Hernandez-Lopez, Stephen D. Davis

Biology

Schinus molle is a relatively new invasive chaparral shrub in the Santa Monica Mountains and has only recently been observed to displace native shrubs like Malosma laurina. To investigate the probable cause of S. molle’s competitive displacement of M. laurina, we compared their water status, photosynthetic rates, electron transport rates, and stomatal conductance to water vapor diffusion during the fall months of 2016. We hypothesized that S. molle would physiologically outperform M. laurina indicated by higher photosynthetic rates, electron transport rates, stomatal conductance rates, and less negative water potential. We found that there was no significant difference between dry …

The Effect Of Drought On The Comparative Fitness Of Purple Needle Grass (Stipa Pulchra) In The Presence Of An Invasive Weed, Grace M. Palmer, Taylor M. Purdy, Stephen D. Davis

Biology

Studies on the relative health of Stipa pulchra, a California native perennial bunchgrass, were conducted at the transplant garden on the Drescher campus of Pepperdine University in the Spring semesters of 2016 and 2017. Following the trend of other perennial native grasses, Stipa pulchra is dwindling due to competition with Avena fatua and other invasive species introduced by human activities. In 2016, in the midst of historic five-year drought in California, stomatal conductance, dark adapted fluorescence, water potential, and height of S. pulchra and A. fatua were recorded and compared. As hypothesized, the wild S. pulchra exhibited greater overall fitness-- …

Neuronal Degeneration And Short-Term Memory Impairment After Tbi, Obiamaraije Igwe

Posters-at-the-Capitol

Traumatic brain injury (TBI) was associated with impaired short-term memory with causes of vehicle accidents and falls. Protein plaques containing fibrinogen (Fg), are associated with memory loss. After TBI, Fg in blood was higher than normal (>~2 mg/ml), which resulted in increased Fg in extravascular space. Therefore, Fg bonded to its endothelial receptor intercellular adhesion molecule-1 (ICAM-1). Fg then interacted with cellular prion protein (PrPC), which had a strong effect on the loss of memory and cognition. Mechanisms of Fg and PrPC complex formation and its functional implication are not known. This present study tested the level of Fg-PrPC …

Creating A Learning Community In The Sciences, Bart De Stasio, Beth De Stasio, Brian Piasecki

Diversity Conference 2017

Science is a collaborative discipline that is best learned through discussion, experimentation and group activity. But several groups of students—particularly students of color, first generation college students and some international students— are often marginalized in our classrooms, labs and are left out of study groups. Their voices aren’t heard, their points of view and interpretations aren’t always appreciated and the learning of these students is thwarted. To address these issues, we have been involved in forming and designing two groups that have been functioning for the past two years: LEDS (Lawrentians Enhancing Diversity in the Sciences) and BioCore, a supplementary …

Ecological And Organic Life Safety Concerns Of Hfo-1234yf, Alberni V. Ruiz

STAR Program Research Presentations

While at NOAA my research was directed by the inquiry of whether or not HFO-1234yf, a new compound being introduced into coolant system and replacing greenhouse gases HFC, is harmful to organic life. Using the computer program Matlab I was able to develop figures that represented the concentration of HFO-1234yf (HFO) in 12 different tower locations throughout the country. Comparing and contrasting concentrations of this HFO compound at each site led me to the question the possible harmful side effects this compound could bring to organic life due to the fact that concentration levels are increasing, with one factor being …

Resistance To Xylem Cavitation In Evergreen Ferns Correlates With Seasonal Dehydration Levels, Not Mechanical Strength, Helen I. Holmlund, Kaitlyn E. Sauer, Breahna M. Gillespie, Jarmila Pittermann, Stephen D. Davis

Biology

Ferns in the Santa Monica Mountains of southern California display a range of responses to severe drought. In this study, we further characterized the traits that may contribute to fern survival in a mediterranean-type climate. Due to anatomical differences between ferns and angiosperms, we predicted that ferns would exhibit no correlation between stipe mechanical strength and vulnerability to water stress-induced cavitation of stipe xylem. However, we predicted that ferns would show a correlation between seasonal water stress (minimum water potential) and cavitation resistance. Our results support these hypotheses; however, we must increase our sample size of evergreen fern species in …

Potential Recovery From Drought-Induced Dieback In A Keystone Chaparral Species, Malosma Laurina, Guinevere X. Mesh, Natalie M. Aguirre, Stephen D. Davis

Featured Research

After five years of protracted drought and water-related dieback and mortality, the coastal chaparral ecosystems of the Santa Monica Mountains have finally received increased precipitation. As a co-dominant plant species in this region, Malosma laurina (common name Laurel Sumac), provides an important indication of environmental change. This study examines the effect of the increased precipitation of the 2016-2017 rainy season on potential recovery from drought-induced dieback in M. laurina. This study shows a significant increase in tissue hydration levels and photosynthetic production of dieback plants during post-drought recovery (2017) and between irrigated control sites and dieback sites.

Consumer Agricultural Education: Starting At The High School Level Health Class, Cecilia Teresa Acosta

Agricultural Education and Communication

The purpose of this project is to analyze and understand the communication gap between the farmer and consumer in order to create a dialogue about misconceptions in the media. Often rumors in the media worry or mislead the consumer in his or her buying choices. In order for consumers to understand what they are buying, and critically analyze media information, it is necessary to teach agricultural education at the high school level health class. This project will showcase how to start this education in order to bridge the communication gap starting with five crucial and common food-packaging labels. These labels …

Applied Drug Development And Combinatorial Strategies For Antimicrobial Treatment, Steven K. Lai Hing

Andrews Research Conference

Streptococcus mutans JH1140 is a strain of bacteria which produces a lantibiotic product, named mutacin 1140. Mutacin 1140 has been shown to be effective at inhibiting Gram-positive bacterial infections caused by Staphylococcus aureus and Streptococcus pneumoniae. Mutacin 1140 is a ribosomally synthesized peptide antibiotic that undergoes extensive posttranslational modifications (PTM). We have found that Mutacin 1140 and an aminoglycoside, Kanamycin, when combined together, act synergistically against Staphylococcus aureus. This was determined by performing serial kill curve dilution overlays on solid media, followed up with kill curve by microdilution plate, and most recently confirmed with kill curve CFU count plates …

Capstone: The Biopsychosocial Approach To The Mind-Brain-Body Connection, Erica Stagliano

Research Day

Introduction

The mind-brain-body connection The relationship between the mind, brain, and body was the highlight of the Neurobehavioral Biomedical Sciences Masters Concentration. While the brain and body are concrete entities, the mind is more abstract and complex and is different from one individual to another. The idea of the mind encompasses opinions, personality, and emotion, which, although seemingly philosophical, have been shown to have a real impact on physical health.

Mental Health and Primary Care Primary care providers are becoming more involved in the role of managing mental health, particularly depression and suicidal patients. 50% of all patients who commit …

Pcom Biomedical Sciences Neuro-Behavior Track: Pilot Students' Perspective, Jenna Wynn, Catherine Tauro, Erica Stagliano

Research Day

INTRODUCTION: Three Master’s degree candidate students opted to pilot a neuro-behavior concentration track after completing the first year of core Biomedical Sciences courses.

METHODS: Courses from the Mental Health Counseling, School Psychology and Clinical Psychology programs as well as select classes from the second year Doctor of Osteopathic Medicine Clinical and Basic Neuroscience course were integrated into the curriculum. Routine discussions and additional clinical or research experiences enhanced the understanding and appreciation of the combination of courses from the various disciplines.

RESULTS: The integrated curriculum provides a unique angle to view the neuro-bio-psycho-social contributions to studying neuroscience …

The Effects Of Urbanization On Nitrogen Processing In Urban Streams, Peter Francissen, Dr. Kevin Geedey, Dr. Michael Reisner

Celebration of Learning

Urban stream syndrome is described as the deterioration of stream health in an urbanized watershed and is associated with the loss of ecosystem services, which in turn degrades downstream environments. One key symptom of the urban stream syndrome is reduced processing of inorganic nitrogen. Previous research suggests that as urbanization increases and water quality decreases, the uptake length (Sw) of inorganic N increases. This indicates that the stream is increasing the export of N downstream compared to in situ incorporation of N into the ecosystem. We measured uptake length (Sw) of NO3, using a pulse addition method, along 9 different …

Deer Droppings As A Diverse Invertebrate Habitat, Allison Furr, Dr. Kevin Geedey

Celebration of Learning

This project was performed at Augustana's Green Wing Environmental Laboratory and studied the richness and diversity of soil invertebrates in two conditions, deer poop enriched and surrounding soil. Soil invertebrates play an important role in soil quality which greatly affects ecosystems. The hypothesis of this study was that the diversity and richness would be the higher in the poop enriched soil samples. Soil samples were collected, Burlese funnels were used to collect the invertebrates, the invertebrates were examined under the microscope, and were assigned to taxa. The number of taxa (richness) and the number of individuals in each taxa (Simpson's …

A Behavioral Prerequisite For The Genetic Analysis Of Auditory Feature Detection Mechanisms In Female Crickets, Rebecca L. Blisko

Senior Honors Projects

Sexual dimorphism is exhibited across all cricket species and is a central aspect of the mating processes of these insects. Only male crickets possess wing structures and pattern generators in the central nervous system that allow them to produce a mating call that is unique to their species in order to attract conspecific females. Conspecific females possess an auditory feature detection circuit in the central nervous system that is capable of detecting the species-specific frequency and temporal pattern of sound pulses within a male call. In order for dimorphic differences in mating behavior to result in successful continuation of a …

The New Penicillin?, Nikki Huynh

Nikki Huynh

Comparative Fitness Of Transplanted Nassella Pulchra: A Study Of Native And Invasive Grasses, Grace Palmer, Yash Pandey, Isabelle Panos

Featured Research

Previous study of the fitness of California, perennial N. pulchra was conducted at the transplant garden on the Drescher campus of Pepperdine University in the spring of 2016. A follow up study was conducted to understand how the recent increase in rainfall has affected the comparative health of N. pulchra in the transplant garden and in the wild, as well as the health of the invasive, annual grass A. fatua. The height, water potential, photoprotection, and stomatal conductance were measured in transplant N. pulchra, wild N. pulchra, and the competing A. fatua. It was hypothesized that A. fatua …

A Comparative Study Of Adults Vs. Resprouts’ Stomatal Conductance And Xylem Water Potential In Malosma Laurina, Lauren Dam, Brinna Lee, Sarah Dahlberg, Stephen Davis

Featured Research

The purpose of this study is to compare the stomatal conductance and xylem water potential between adults and resprouts of Malosma laurina growing at the Drescher Campus at Pepperdine University. Our data suggest that stomatal conductance and xylem water potential of adult and resprout M. laurina are not significantly different (p = 0.09312, p = 0.7064 respectively), implying that M. laurina at that study site has had sufficient time to recover from the drought due to the increased levels of rainfall.

Solar Tracking Fitness In Native Lupulinus Succulentus Vs. Non-Native Malva Sylvestris, Kathryn Maidlow, Logan Scott

Featured Research

For this experiment, we hypothesized, that while both native and non-native species use solar tracking, the native species Lupulinus succulentus (bluebonnet) will solar track to increase light levels with low leaf temperatures; however, the non-native species Malva sylvestris (cheeseweed) will solar track to increase light levels with an elevated leaf temperature over the native species. Solar tracking was also hypothesized as a significant benefit to each plant species, thus we assumed that if a leaf was prevented from solar tracking that we would see a difference between the solar trackers and non-solar trackers of each species. We decided to use …

Reflectance, Transmittance, And Absorbance Values In Salvia Apiana
 Result In Better Performance Than Salvia Mellifera In Drought- Like Conditions, Haley Bekins, Caroline Boone, Kristen Hardin

Featured Research

Salvia apiana, due to the physically lighter color and thickness of the leaves, will have higher reflectance values, lower transmittance values, and lower absorbance values than Salvia mellifera. These measurements exemplify characteristics of a better adapted species for droughts, and then the absorption values can be used to calculate more information on the species like ERT. We measured transmittance and reflectance of six leaves from randomly selected plants of both species through the use of an integrating sphere. After obtaining the R and T value of each plant, we calculated the leaf absorbance,α. This was done by using the …

Dark-Adapted Fluorescence And Stomatal Conductance After Dcmu (3-(3,4-Dichlorophenyl)-1, 1-Dimethylurea)) Exposure On Malva Parviflora Plants, Piueti Maka, Mia Bryant, Isabelle Sarwono

Featured Research

The purpose of this experiment was to determine the disturbance effect of indirect exposure to DCMU (3-[3,4-dichlorophenyl]-1,1-dimethylurea), a popular herbicide, on dark adapted fluorescence and stomatal conductance in Malva parviflora plants. We utilized a test site exposed to sunlight and free from other external interference. Two main apparatuses were used to collect data; stomatal conductance was measured by a leaf porometer, and dark-adapted fluorescence (Fv/Fm) was measured using a Pulse Modulated Fluorometer. Our data yielded significant comparison results for dark-adapted fluorescence (P0.05). Additionally, observations six days after disturbance showed a drastic presence of hollyhock rust (Puccinia malvacearum) and …

A Comparison Of Photoprotection In C3 Plants Between A Native And An Invasive Species, T. Cao, M. Field, K. Godon

Featured Research

Now more so than ever with the increasing demands placed upon plant species as a direct result of climate change, competition between native and invasive species determines which species are able to survive and reproduce. Biologically the two species, native and invasive, carry out the same functions yet it is in how they carry out said functions that they differ. Prior to the commencement of the study the belief was held that the invasive species (here Avena) would contain increased photoprotection than the native species (here Elymus) for it to possess a competitive advantage. Testing of the stated hypothesis including …

Photoprotection Adaptiveness In Native (Lupinus 
Succulentus) And Invasive (Malva Parviflora) Heliotropic Plants, Joseph Davidson, Cameron Juarez, Collin Scott

Featured Research

Addressed here is the question of whether invasive heliotropic plants can adapt better than native heliotropic plants, to conditions in which their solar tracking capabilities are hindered. In order to test this, a heliotropic species native to Southern California (Lupinus succulentus) was compared to a weedy heliotropic species invasive to Southern California (Malva parviflora). We hypothesized that the photoprotection mechanisms of M. parviflora would adapt better to being restrained as it is an invasive species and it was more abundant in the area. Values of Fv’/Fm’ and qN were measured in order to compare the efficacy …

Comparison Of Physiological Measurements And Water Potential Of Malosma Laurina During And After The Drought In Southern California, Nicolette Jessen, Kirstin Van Fleet, Rachel White

Featured Research

After 5 years of drought, southern California has recently experienced increases in precipitation. Malosma laurina is a chaparral shrub that displays vulnerability to fungal infection during severe drought conditions, particularly in its adult branches, resulting in severe dieback throughout the Santa Monica Mountains. M. laurina is known to produce resprout leaves during times of environmental stress that are less affected by the fungus based on its ability to maintain water status and thus are more capable of displaying resilience in more favorable environmental conditions. We hypothesize that the increase in rain will not be enough to alter the vitality of …

C-Myc’S Role On Methylation Of The Gata-2 Gene In Non-Small Cell Lung Carcinoma, Jonathan D. Hajduk

Student Scholar Showcase

Lung cancer accounts for more deaths per year than any other form of cancer, resulting in a total of 158,000 deaths per year in the U.S. Non-small cell lung cancer (NSCLC) is diagnosed in greater than 224,000 Americans every year. Methylation and subsequent downregulation of certain genes has been directly linked to the uncontrolled growth of NSCLC cells. Natural killer (NK) cells are key innate immune cells responsible for apoptosis of cells with incorrect genetic code. It is believed that one component of uncontrolled NSCLC growth is due to the NK cells’ inability to detect errors within NSCLC cells. Perhaps …

The Effect Of Water Levels On Crayfish Aggression, Emory B. Johnson, Sarah E. Blase

Seaver College Research And Scholarly Achievement Symposium

Crayfish are a very prevalent invasive species that affect many different environments all over the world. Crayfish, specifically Procambarus clarkii, are an invasive species that have currently taken a foothold in the Santa Monica mountains and are threatening native stream species. There is currently a severe drought occurring in the Santa Monica mountains. The drought has been reshaping many aquatic environments by limiting space and resources such as food and shelter. Crayfish are a very aggressive species and adversely affect the habitat they inhabit by rapidly colonizing, burrowing, and their voracious diets. Due to the adverse effects crayfish can have …