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Analysis Of Biodiesel Quality Using Reversed Phase High-Performance Liquid Chromatography, Kellyann M. Murphy May 2012

Analysis Of Biodiesel Quality Using Reversed Phase High-Performance Liquid Chromatography, Kellyann M. Murphy

Pomona Senior Theses

The alternative fuel biodiesel is produced from the transesterification of vegetable oils or animal fat to fatty acid methyl esters. Pomona has a reactor on campus that can be used to run this reaction and produce biodiesel. The use of biodiesel has been found to lower air pollutant and greenhouse gas emissions, but can be potentially harmful to the engines if it contains impurities. This paper proposes a method using high-performance liquid chromatography to test the quality of biodiesel. This method utilizes instrumentation and materials that are available in Pomona College's Chemistry Department, requires very little sample preparation, and is …


Implications Of Land Development On Nomadic Pastoralism: Ecological Relaxation And Biosocial Diversity In Human Populations, Hannah R. Bradley May 2012

Implications Of Land Development On Nomadic Pastoralism: Ecological Relaxation And Biosocial Diversity In Human Populations, Hannah R. Bradley

Scripps Senior Theses

Nomadic pastoralism is an ancient subsistence strategy, historically balanced and in continuity with sedentary societies. Sedentarization of nomads occurs normally because of ecological disasters, economic opportunities, urbanization, and government policy. In this paper, I examine the effect of changing land use patterns on nomadic pastoral populations in Asia, Africa, and the Middle East, using biogeographic methodology to further explore the contemporary relationship between humans and their environments. Nomadic population information gleaned from diverse ethnographic studies, and GIS data on anthropogenic biome distributions, were used to calculate changes in nomadic population, area of developed land, and nomadic/sedentary population density over the …


Navigating The Diverse Dimensions Of Stereotypes, With Domain Specific Deficits: Processes Of Trait Judgments About Individuals With Disabilities, Christina G. Boardman May 2012

Navigating The Diverse Dimensions Of Stereotypes, With Domain Specific Deficits: Processes Of Trait Judgments About Individuals With Disabilities, Christina G. Boardman

Scripps Senior Theses

Stereotype groups are interrelated. For example, in Australia, New Zealand, and the United States, racial minorities are referred to special education at a much higher rate than are majority racial groups (Tse, Lloyd, Petchkovsky, and Manaia, 2005; Harry, Arnaiz, Klingner, Sturges, 2008). The Stereotype Content Model describes stereotype relationships in terms of an interaction between competence and warmth. Warmth is the more consistent dimension. The nature of competence remains elusive (Fiske, Cuddy, and Glick, 2007; Fiske, Cuddy, Glick, and Xu, 2002). Knowledge of relationships between stereotype groups, which themselves may be effects of bias, could factor into observed competence effects. …


San Antonio High School Food Justice Program: A Handbook And Evaluation Of Edible Education, Katherine B. Tenneson May 2012

San Antonio High School Food Justice Program: A Handbook And Evaluation Of Edible Education, Katherine B. Tenneson

Pitzer Senior Theses

This senior environmental studies thesis explains and analyzes edible education through a food and gardening program at a continuation high school in Claremont, California. The first chapter situates the program-specific analysis by providing background information of the edible education movement, a history of the Edible Schoolyard in Berkeley, California, and an explanation of why food is a powerful teaching tool. The second chapter delineates the program by describing all of its components and compiling essential resources and teaching documents. The third chapter is based on interviews with 9 of 12 involved students and 7 teachers, and thoroughly explains the outcomes …


Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly May 2012

Arsenic Contamination In Groundwater In Vietnam: An Overview And Analysis Of The Historical, Cultural, Economic, And Political Parameters In The Success Of Various Mitigation Options, Thuy M. Ly

Pomona Senior Theses

Although arsenic is naturally present in the environment, 99% of human exposure to arsenic is through ingestion. Throughout history, arsenic is known as “the king of poisons”; it is mutagenic, carcinogenic, and teratogenic. Even in smaller concentrations, it accumulates in the body and takes decades before any physical symptoms of arsenic poisoning shows. According to the World Health Organization (WHO), the safe concentration of arsenic in drinking water is 10 µg/L. However, this limit is often times ignored until it is decades too late and people begin showing symptoms of having been poisoned.

This is the current situation for Vietnam, …


Sediment Removal From The San Gabriel Mountains, Mary C. Ferguson May 2012

Sediment Removal From The San Gabriel Mountains, Mary C. Ferguson

Pitzer Senior Theses

The issue of sediment removal from the San Gabriel Mountains has been a complex issue that has created problems with beach replenishment, habitat destruction and the need to spend millions of dollars at regular intervals to avoid safety hazards. Most recently 11 acres of riparian habitat, including 179 oaks and 70 sycamores, were removed for sediment placement. Other sites including Hahamongna Watershed Park and La Tuna Canyon also face a similar fate. This thesis questions: How did we get to this point of destroying habitat to dump sediment which is viewed as waste product? What are the barriers for creating …


Cultivating An Opportunity: Access And Inclusion In Seattle's Community Gardens, Alice K. Opalka May 2012

Cultivating An Opportunity: Access And Inclusion In Seattle's Community Gardens, Alice K. Opalka

Scripps Senior Theses

This thesis explores the social dynamics of community gardens and their participation within them in the contemporary food justice movement in Seattle, Washington. Community gardens are seen as solutions to myriad urban and environmental problems, such as food deserts, community empowerment, urban greening, environmental education and sustainability of the food system. Three case studies of Seattle organizations, the P-Patch Program, Lettuce Link and Alleycat Acres, provide a basis for analysis of the purported benefit of community empowerment as a function of organizational structure, history and policies. City government support, flexibility, and a critical outlook towards the processes of inclusion and …


31p Nmr Of Backbone Conformation And Dynamics In Dna At Cre Binding Site In Terms Of Sequence Context, Kelly A. Garton Apr 2012

31p Nmr Of Backbone Conformation And Dynamics In Dna At Cre Binding Site In Terms Of Sequence Context, Kelly A. Garton

Scripps Senior Theses

The Cre sequence (ACGT) is a site responsible for the binding of specific transcription factors that determine the activation of genes. Due to its major role in gene transcription, it has become a subject of immense research. The binding of transcription factors to the Cre binding site has been determined to be dependent on DNA conformation. In this study, the effects of flanking sequence around the Cre binding site on the conformation and the dynamics of DNA were investigated. The Cre binding site was studied in its native form with differing flanking sequences to determine the BI/BII profile (conformation) and …


Effects Of Cannabidiol On Mk-801-Induced Locomotor Sensitization In Mice, Sara K. Cronin Apr 2012

Effects Of Cannabidiol On Mk-801-Induced Locomotor Sensitization In Mice, Sara K. Cronin

Scripps Senior Theses

Previous research has shown that cannabidiol (CBD), a non-psychoactive compound in the hemp plant Cannabis sativa, may be useful in treating drug craving, one of the hallmarks of drug addiction. However, the neural mechanism by which CBD attenuates craving is poorly understood. Studies from other laboratories have shown that neuroplastic changes associated with brain NMDA glutamate systems may at least partially serve as a neural mechanism for craving. In the current study, the noncompetitive NMDA receptor antagonist MK-801 maleate was used to induce locomotor sensitization, a form of NMDA glutamate-mediated neuroplasticity, in mice to test the sensitization-attenuating potential of …


The Effects Of Invasive Grasses On The Survival And Germination Of Native Forbs, Rachel A. King Apr 2012

The Effects Of Invasive Grasses On The Survival And Germination Of Native Forbs, Rachel A. King

Scripps Senior Theses

Invasive species are an increasingly severe conservation problem that can dramatically alter native plant communities. Although ecologists have proposed many mechanisms for the dominance of invasive species, superior competitive ability is one of the longest standing hypotheses. In winter annual plant communities, germination timing affects competition among plants. I hypothesized that grass invasion has changed the costs and benefits of early and late germination, and that species with flexible germination timing would compete better with invasives. Experiments at the Bernard Field Station in Claremont, CA and germinator trials in a controlled environment were used to examine the survivorship and germination …


The Role Of Thd2 In Deposition-Related Deactylation And Chromatin Maturation, T. Alexandria Dumas Apr 2012

The Role Of Thd2 In Deposition-Related Deactylation And Chromatin Maturation, T. Alexandria Dumas

Scripps Senior Theses

During S phase of the cell cycle, newly synthesized histones are acetylated in the cytoplasm in patterns specific to DNA replication. Once incorporated into nucleosomes, these histones are rapidly deacetylated by enzymes known as histone deacetylases. Though common in all organisms, the significance of this molecular mechanism is not fully understood. Homologous to HDAC6 in humans and HDA1 in budding yeast, Tetrahymena histone deacetylase 2 (Thd2) has been identified as the only known histone deacetylase that performs this task in the unicellular eukaryote Tetrahymena thermophila. Localizing to the transcriptionally inactive germline nucleus, the micronucleus, Thd2 has been found to deacetylate …


Neural Synchrony In The Zebra Finch Brain, Sydney Pia Goings Apr 2012

Neural Synchrony In The Zebra Finch Brain, Sydney Pia Goings

Scripps Senior Theses

I am interested in discovering the role of field potential oscillations in producing synchrony within the song system of the male zebra finch brain. An important function attributed to neural synchrony is sensorimotor integration. In the production of birdsong, sensorimotor integration is crucial, as auditory feedback is necessary for the maintenance of the song. A cortical-thalamic-cortical feedback loop is thought to play a role in the integration of auditory and motor information for the purpose of producing song. Synchronous activity has been observed between at least two nuclei in this feedback loop, MMAN and HVC. Since low frequency field potential …


Systematics, Biogeography And Leaf Anatomy And Architecture Of Bursera Subgen. Bursera (Burseraceae) In The Greater Antilles And The Bahamas, María Cristina Martínez-Habibe Jan 2012

Systematics, Biogeography And Leaf Anatomy And Architecture Of Bursera Subgen. Bursera (Burseraceae) In The Greater Antilles And The Bahamas, María Cristina Martínez-Habibe

CGU Theses & Dissertations

This dissertation presents a comprehensive study on the origin and evolutionary relationships of the species of Bursera in Cuba, Hispaniola, Jamaica and the Bahamas. The goals of the first chapter were to test monophyly of the group, revisit a recent transfer of two species of Bursera to Commiphora, and place recently discovered mainland species using the reconstructed phylogenies. Additionally, divergence estimations using fossils were used as independent tests of several hypotheses regarding the arrival of the modern biota to the Greater Antilles and Bahamas (GAB). I conclude that all endemic taxonomic entities of the genus in this region belong …


The Potential Application Of Weather Derivatives To Hedge Harvest Value Risk In The Champagne Region Of France, Andrew W. Yandell Jan 2012

The Potential Application Of Weather Derivatives To Hedge Harvest Value Risk In The Champagne Region Of France, Andrew W. Yandell

CMC Senior Theses

In Champagne, France grape growers and and winemakers work together to make the world's most iconic sparkling wine. Part of what makes Champagne so celebrated is its reputation for constant quality: only the best grapes are used to make wine. In poor vintage years, grape growers sell less grapes to winemakers; poor vintages are the result of bad weather. This presents the opportunity for grape growers to hedge the risk of poor weather and resulting lower harvest values with weather derivatives. This study explores the potential for grape growers to trade them to effectively hedge against low harvest values by …


Factors Influencing Web Tenure In A Tropical Spider And Comparison Between Forest And Non-Forest Habitats, Daniella R. Barraza Jan 2012

Factors Influencing Web Tenure In A Tropical Spider And Comparison Between Forest And Non-Forest Habitats, Daniella R. Barraza

Scripps Senior Theses

Webs are fundamental to the ecology of Nephila clavipes, the golden orb-weaver spider, because they serve as sites for prey capture, reproduction, competition, predation, and parasitism. In addition to the presence of the female N. clavipes, males and kleptoparasites reside on the web in varying numbers. Webs are also found in clusters with conspecific females. Web site selection and length of web tenure is a behavioral decision vital to the spider’s fitness and the ecology of her species. I conducted a field census to quantify these factors and analyze their influence on web tenure, compare web ecology between a forest …


A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel Jan 2012

A Proposal To Test The Effects Of Factor Ecat1 On Pluripotency, From Reprogramming To Differentiation Of Human Somatic Cells, Vritti R. Goel

CMC Senior Theses

The field of stem cell research has been growing more because of the interest in using stem cells to cure diseases and heal injuries. Human embryonic stem cells, because of the controversy surrounding them—and subsequently the difficulties in acquiring samples of the existing aging cell lines—can only be used in limited capacities. While the development of induced pluripotent stem cells in the last decade has allowed the field to progress closer to medical treatments, the low efficiency of reprogramming a somatic cell to a pluripotent state, and the vast molecular and genomic differences between human embryonic stem cells and human …