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Full-Text Articles in Physical Sciences and Mathematics

C. Compactum Acts As A Comprehensive Climate Archive And Ecological Foundation In The Labrador Sea, Sadie Heckman Jan 2024

C. Compactum Acts As A Comprehensive Climate Archive And Ecological Foundation In The Labrador Sea, Sadie Heckman

CMC Senior Theses

Clathromorphum compactum, a species of crustose coralline algae (CCA), is incredibly valuable for the future of high latitude ocean health, both as a comprehensive archive of changing ocean conditions, and ecologically as a foundational species for promoting biodiversity. Previous work establishes C. compactum as an effective climate proxy, and its life history provides several advantages for this use. C. compactum grow in nongeniculate, generally radial formations on hard substrates, over a wide distribution in mid-to-high latitude oceans and at subtidal depth ranges. Indeterminate growth leads to extreme longevity in C. compactum (Halfar et al., 2008), and growth rates are relatively …


Using Computational Fluid Dynamics And Optical Sensor Technology To Scale Cell Culture Platforms, Mandar Makwana Jan 2023

Using Computational Fluid Dynamics And Optical Sensor Technology To Scale Cell Culture Platforms, Mandar Makwana

KGI Theses and Dissertations

Different cell culture vessels ranging from micro scale to laboratory scale to commercial scale play critical role in upstream process development for biologics manufacturing. Based on the mode of operation, cell culture vessels have different hydrodynamic environments, making it challenging to scale. Integrated approaches using computational tools supported by experimental studies can overcome these challenges. Computational Fluid Dynamics (CFD) is one such tool that can simulate hydrodynamics within the cell culture vessels and can provide insights at macro and micro-scale. Accuracy of a CFD model significantly depends on the fluid model and assumptions. Traditionally, simple two-equation fluid models were developed …


Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson Jan 2023

Quantifying The Carbon Stored And Sequestered By The Trees On Pomona College’S Campus, Paola A. Giron-Carson

Scripps Senior Theses

We are experiencing a climate crisis that must be confronted with strategic mitigation. Pomona College contributes to the climate crisis through its emissions for which there is a baseline record. However there is no baseline record of the climate mitigation currently performed by the trees on Pomona’s campus through carbon storage. This study seeks to determine a current baseline quantity of carbon stored and sequestrated by Pomona’s trees as well as possible courses of climate mitigation for Pomona College to take. Initial information gathering was conducted through interviews with several stakeholders. This study was conducted using data collected prior to …


Analysis Of Biologically Effective Dose For Retroactive Yttrium-90 Trans-Arterial Radioembolization Treatment Optimization, Mj Lindsey Jan 2023

Analysis Of Biologically Effective Dose For Retroactive Yttrium-90 Trans-Arterial Radioembolization Treatment Optimization, Mj Lindsey

CMC Senior Theses

Trans-arterial radioembolization (TARE) is a protracted modality of radiation therapy where radionuclides labeled with Yttrium-90 (90Y) are inserted inside a patient's hepatic artery to treat hepatocellular carcinoma (HCC). While TARE has been shown to be a clinically effective and safe treatment, there is little understanding of the radiobiological relationship between absorbed dose and tissue response, and thus there is no dosimetric standard for treatment planning. The Biologically Effective Dose (BED) formalism, derived from the Linear-Quadratic model of radiobiology, is used to weigh the absorbed dose by the time pattern of delivery. BED is a virtual dose that can …


Stem Education And Retention For Black Women Using High-Impact Practices: Historically Black Colleges And Universities Vs. Predominantly White Liberal Arts Colleges, Annette Njei Jan 2023

Stem Education And Retention For Black Women Using High-Impact Practices: Historically Black Colleges And Universities Vs. Predominantly White Liberal Arts Colleges, Annette Njei

CMC Senior Theses

Black women are significantly underrepresented within the fields of science, technology, engineering, and mathematics (STEM). To address this, the Association of American Colleges & Universities crafted ten high-impact practices to increase student engagement and promote retention. This research paper examines how three specific high-impact practices (learning communities, mentoring, and undergraduate research experience) are utilized in STEM education.This research paper explores and compares the best high impact approaches that successfully teach and retain Black women within the various fields of STEM within the differing academic environments of historically Black colleges & universities ( HBCUs) and predominantly white liberal art colleges (PWLACs). …


Examining Soil Microbial Diversity In Transition Zones Between Corn Fields And Restored Prairie In The Upper Midwest, Anna M. Burns Jan 2022

Examining Soil Microbial Diversity In Transition Zones Between Corn Fields And Restored Prairie In The Upper Midwest, Anna M. Burns

Scripps Senior Theses

Prairies were once the largest ecosystem in North America, but agriculture and settlement has destroyed up to 99% of their pre-colonization extent. Prairie restorations are a strategy to recover the biodiversity and carbon sequestration functions of these grasslands, but typically occur in isolated strips between agricultural fields. My thesis analyzes how effective prairie restorations in the Liberty Prairie (northeastern Illinois) are at recovering the diversity of the prairie soil microbiome, focusing on verrucomicrobia abundance, alpha diversity, and soil physical characteristics.


Here, There, And Everywhere: Probing Ubiquitin-Cavitand Binding Via 15n-1h Hsqc, Julia Didziulis Jan 2022

Here, There, And Everywhere: Probing Ubiquitin-Cavitand Binding Via 15n-1h Hsqc, Julia Didziulis

Scripps Senior Theses

Ubiquitination and other post-translational modifications play a major role in the proliferation of many neurodegenerative diseases, developmental disorders, and cancers, and as such are subjects of recently increased biochemical interest. Expanding upon such research, this study confirmed a robust method of ubiquitin expression and purification, then used 15N-1H HSQC to analyze ubiquitin samples containing varying concentrations of a deep cavitand with affinity for lysine and arginine side chains. In the pure ubiquitin spectrum, arginine side chain chemical shifts were detected in the nitrogen 80-85 ppm range and lysine side chain signals were undetected. However, upon introduction of the cavitand, collection …


Footprints On The Prairie: Examining The Interlocking Land Histories Of The Liberty Prairie Reserve, Illinois, Anna M. Burns Jan 2022

Footprints On The Prairie: Examining The Interlocking Land Histories Of The Liberty Prairie Reserve, Illinois, Anna M. Burns

Scripps Senior Theses

This thesis begins with the local history of the Liberty Prairie, the land where I conducted the ecological field-work that I later discuss in my second thesis on soil microbiome diversity (“Examining Soil Microbial Diversity in Transition Zones Between Corn Fields and Restored Prairie in the Upper Midwest"). I examine the Indigenous histories of the land, and the conflicts between the Bodwéwadmi and Euro-American settlers that resulted in the land being farmed for cattle, corn, and soy for over a hundred and fifty years. I then take a step back and analyze the broader historical contexts of Midwestern Corn Belt …


Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf Jan 2022

Spatial Geochemical Changes In Central And East Texas Soils Over Time Resulting From Human Decomposition, Isabela Marisol Overturf

CMC Senior Theses

Human decomposition is studied to aid forensic investigations and better understand the impact of cemeteries on urban resources like soil and groundwater. The purpose of this study was to identify changes in soil geochemistry at and around a human grave to search for lateral nutrient movement and possibly identify new patterns in elemental concentrations that could be used in estimating post-mortem intervals (PMIs). At the Forensic Anthropology Research Facility (FARF) at Texas State San Marcos, soil samples were collected from a shallow grave over the course of 54 days to conduct analysis for organic matter content, texture, pH, and bulk …


Energy As A Limiting Factor In Neuronal Seizure Control: A Mathematical Model, Sophia E. Epstein Jan 2022

Energy As A Limiting Factor In Neuronal Seizure Control: A Mathematical Model, Sophia E. Epstein

CMC Senior Theses

The majority of seizures are self-limiting. Within a few minutes, the observed neuronal synchrony and deviant dynamics of a tonic-clonic or generalized seizure often terminate. However, a small epilesia partialis continua can occur for years. The mechanisms that regulate subcortical activity of neuronal firing and seizure control are poorly understood. Published studies, however, through PET scans, ketogenic treatments, and in vivo mouse experiments, observe hypermetabolism followed by metabolic suppression. These observations indicate that energy can play a key role in mediating seizure dynamics. In this research, I seek to explore this hypothesis and propose a mathematical framework to model how …


Heat Stress During Larval Stages On Coral Survivorship For M. Capitata, Sarah Woo Jan 2021

Heat Stress During Larval Stages On Coral Survivorship For M. Capitata, Sarah Woo

Pitzer Senior Theses

Very little is known about how heat stress during larvae stages effect larvae survivorship, early coral recruit settlement, and later stage coral survivorship. We focused on determining how heat stress during larvae stages effected Montipora capitata survivorship over time. After thermally stressing larvae, we asked how many larvae survived the treatment, how the treatment affected settlement, how many larvae survived the heat treatment but did not settle, and later stage coral survivorship experienced residual effects from the heat stress treatment. We exposed coral larvae to ambient seawater temperatures at 30°C and heated seawater temperatures to 34°C for an hour and …


Environmental Controls On The Spatial Distribution Of Greenfin Darters And Biodiversity In The Blue Ridge Mountains, Dri Tattersfield Jan 2021

Environmental Controls On The Spatial Distribution Of Greenfin Darters And Biodiversity In The Blue Ridge Mountains, Dri Tattersfield

CMC Senior Theses

Disproportionate concentrations of biodiversity in mountains worldwide suggest linkages between geologic processes and biodiversity that are not yet well understood. The Tennessee River Basin in the Blue Ridge Mountains of the southeastern U.S. is a global hotspot for freshwater fish biodiversity. To investigate drivers of biodiversity in the Tennessee River Basin, and explore links to geologic processes, I study the Greenfin Darter (Nothonotus chlorobranchius), a small fish endemic to the upper Tennessee River Basin. I use generalized linear models (GLMs) to evaluate the influence of topography, lithology, climate and land use on the distribution of the Greenfin Darter, …


Neither “Post-War” Nor Post-Pregnancy Paranoia: How America’S War On Drugs Continues To Perpetuate Disparate Incarceration Outcomes For Pregnant, Substance-Involved Offenders, Becca S. Zimmerman Jan 2021

Neither “Post-War” Nor Post-Pregnancy Paranoia: How America’S War On Drugs Continues To Perpetuate Disparate Incarceration Outcomes For Pregnant, Substance-Involved Offenders, Becca S. Zimmerman

Pitzer Senior Theses

This thesis investigates the unique interactions between pregnancy, substance involvement, and race as they relate to the War on Drugs and the hyper-incarceration of women. Using ordinary least square regression analyses and data from the Bureau of Justice Statistics’ 2016 Survey of Prison Inmates, I examine if (and how) pregnancy status, drug use, race, and their interactions influence two length of incarceration outcomes: sentence length and amount of time spent in jail between arrest and imprisonment. The results collectively indicate that pregnancy decreases length of incarceration outcomes for those offenders who are not substance-involved but not evenhandedly -- benefitting white …


Using Nmr Spectroscopy And Computational Chemistry To Confirm The Structure Of Novel Antibiotic Nocamycin O, Stephanie Lewis Jan 2021

Using Nmr Spectroscopy And Computational Chemistry To Confirm The Structure Of Novel Antibiotic Nocamycin O, Stephanie Lewis

CMC Senior Theses

In recent years, many medically promising antibiotics have been discovered in nature, especially in insect-microbe symbioses. One of the better-studied examples of this kind of defensive relationship is that of fungus-growing ants and the antibiotic-producing Actinobacteria. These bacteria produce several defensive chemicals with myriad uses, including one antibiotic that inhibits the growth of several bacterial strains, including other Actinobacteria. This antibiotic (known as nocamycin O) is a promising candidate for medicinal use due to its similarities to bacterial RNA polymerase inhibitors tirandamycin and streptolydigin, which inhibit several human pathogens. The determination of the structure of nocamycin O will be an …


Modeling Residence Time Distribution Of Chromatographic Perfusion Resin For Large Biopharmaceutical Molecules: A Computational Fluid Dynamic Study, Kevin Vehar Dec 2020

Modeling Residence Time Distribution Of Chromatographic Perfusion Resin For Large Biopharmaceutical Molecules: A Computational Fluid Dynamic Study, Kevin Vehar

KGI Theses and Dissertations

The need for production processes of large biotherapeutic particles, such as virus-based particles and extracellular vesicles, has risen due to increased demand in the development of vaccinations, gene therapies, and cancer treatments. Liquid chromatography plays a significant role in the purification process and is routinely used with therapeutic protein production. However, performance with larger macromolecules is often inconsistent, and parameter estimation for process development can be extremely time- and resource-intensive. This thesis aimed to utilize advances in computational fluid dynamic (CFD) modeling to generate a first-principle model of the chromatographic process while minimizing model parameter estimation's physical resource demand. Specifically, …


Intercropping For Water Conservation: Environmental And Economic Implications Of A Sustainable Farming Practice In California's Central Valley, Sophie Baker Jan 2020

Intercropping For Water Conservation: Environmental And Economic Implications Of A Sustainable Farming Practice In California's Central Valley, Sophie Baker

Scripps Senior Theses

California’s agricultural sector is the biggest water consumer in the state and faces intense pressure to reduce its overall water usage. Industrialized monoculture systems dominate the industry and often disregard long-term environmental and economic externalities for short-term profit maximization. To maintain longstanding food security and economic stability as well as protect the state’s water supply, it is critical that these systems transition to more sustainable and resilient production mechanisms. As an alternative to monoculture, intercropping affords greater potential to conserve water, protect soil quality, and increase crop yields, among other metrics of sustainability. However, there has been much controversy over …


Use Of Kalman Filtering In State And Parameter Estimation Of Diabetes Models, Cassidy Le Jan 2020

Use Of Kalman Filtering In State And Parameter Estimation Of Diabetes Models, Cassidy Le

HMC Senior Theses

Diabetes continues to affect many lives every year, putting those affected by it at higher risk of serious health issues. Despite many efforts, there currently is no cure for diabetes. Nevertheless, researchers continue to study diabetes in hopes of understanding the disease and how it affects people, creating mathematical models to simulate the onset and progression of diabetes. Recent research by David J. Albers, Matthew E. Levine, Andrew Stuart, Lena Mamykina, Bruce Gluckman, and George Hripcsak1 has suggested that these models can be furthered through the use of Data Assimilation, a regression method that synchronizes a model with a …


Complex Ciliary Flows Around Stentor Polymorphus In Solutions Of 2% Buttermilk And Chlamydomonas Reinhardtii, Eliana B. Smithstein Jan 2020

Complex Ciliary Flows Around Stentor Polymorphus In Solutions Of 2% Buttermilk And Chlamydomonas Reinhardtii, Eliana B. Smithstein

Scripps Senior Theses

Stentor are large, unicellular ciliates of the Heterotricha order. They live in both freshwater and marine habitats and are mostly found in ponds. I studied Stentor polymorphus, which is a species of Stentor only recently discovered to be lab culturable. They range from 0.5-1.5mm in length and are unusual because they live with endosymbiotic algae and are much more likely than other, more widely studied, species of Stentor to form aggregates while they are eating. There are three main components to this thesis: First, I established protocols for keeping a viable S. polymorphus culture, since no protocols had been …


Gravity-Drawing Flexible Silicone Filaments As Fiber Optics And Model Foldamers, Katherine Snell Jan 2020

Gravity-Drawing Flexible Silicone Filaments As Fiber Optics And Model Foldamers, Katherine Snell

CMC Senior Theses

Here, we present a method of gravity-drawing polydimethylsiloxane (PDMS) silicone fibers with application as fiber optics and as model foldamers. Beginning as a viscous liquid, PDMS is cured using heat until its measured viscosity reaches 4000 mPa•s. The semi-cured elastomer is then extruded through a tube furnace to produce thin (diameters on the order of hundred micrometers) filaments with scalable lengths. PDMS is biocompatible, gas-permeable, flexible, and hydrophobic. Additionally, the PDMS surface hydrophobicity can be modified via UV exposure, O2 plasma, and corona discharge. We demonstrate the patternibility (i.e patterns of hydrophobicity) of PDMS fibers, adding complexity to potential foldamer …


Machine Learning Methods For The Analysis Of Metagenomes, Vito Adrian Cantu Alessio Robles Jan 2020

Machine Learning Methods For The Analysis Of Metagenomes, Vito Adrian Cantu Alessio Robles

CGU Theses & Dissertations

As of October 2020, there are 18.6 × 1015 DNA base pairs publicly available in the Sequence Read Archive and this number is growing at an exponential rate. As DNA sequencing prices continue to drop, many research groups around the world have incorporated high throughput sequencing in their research, giving us access to sequences from many distinct ecosystems. This has revolutionized the field of metagenomics, which aims to fully characterize all organisms and their interactions in a particular system. Nevertheless, the plethora of available data has made its analysis difficult as traditional techniques such as genome assembly or sequence alignment …


Antifungal Defense Molecules From Bacterial Symbionts Of North American Trachymyrmex Ants, Georgia Scherer Jan 2020

Antifungal Defense Molecules From Bacterial Symbionts Of North American Trachymyrmex Ants, Georgia Scherer

CMC Senior Theses

Defensive symbioses, in which microbes provide molecular defenses for an animal host, hold great potential as untapped sources of therapeutically useful antibiotics. Fungus-growing ants use antifungal defenses from bacterial symbionts to suppress pathogenic fungi in their nests. Preliminary chemical investigations of symbiotic bacteria from this large family of ants have uncovered novel antifungal molecules with therapeutic potential, such as dentigerumycin and selvamicin.

In this study, the bacterial symbionts of North American Trachymyrmex fungus-growing ants are investigated for antifungal molecules. Plate-based bioassays using ecologically-relevant fungal pathogens confirmed that these bacteria have antifungal activity. In order to purify and identify the antifungal …


Shizen Nōhō: Restoring The Relationship Between Food, Nature, And People In Japan, Katharine Graham Jan 2019

Shizen Nōhō: Restoring The Relationship Between Food, Nature, And People In Japan, Katharine Graham

Scripps Senior Theses

In Japan’s postwar era, agriculture has become highly industrialized, involving heavy machinery, chemical fertilizers, and pesticides, all in the name of “progress.” Through employing such practices, humans have attempted to improve upon nature’s way of doing things, and in turn have degraded the soil’s fertility, natural ecosystems, and human health. In response to this, Shizen Nōhō has emerged in Japan as an alternative way of cultivating food. Shizen Nōhō practitioners challenge the notion that we need chemical fertilizers, pesticides, and machinery to farm successfully. Rather, they advocate for a way of growing food that functions seamlessly with natural ecosystems. This …


Farm To Label: A Critique Of Consumer Activism In The Sustainable Food Movement, Olivia Whitener Jan 2019

Farm To Label: A Critique Of Consumer Activism In The Sustainable Food Movement, Olivia Whitener

Pomona Senior Theses

“Local,” “organic,” “natural,” and “Fairtrade” are just several of the many claims adorning the food products that line grocery store shelves. These promises of environmental sustainability and social responsibility are pillars of the “good food revolution” sweeping the nation as consumers demand alternatives to the products of the industrial food system. Green consumerism, the premise that consumer demand for environmentally sustainable goods will bring about ecologically beneficial outcomes, is at the heart of the sustainable food movement. This thesis takes a critical look at the operation of green consumerism in the food system. It explores the ideology and shortcomings of …


In The Eye Of The Storm: Houston After Hurricane Harvey, Brandon Tolentino-Serrano Jan 2019

In The Eye Of The Storm: Houston After Hurricane Harvey, Brandon Tolentino-Serrano

Pomona Senior Theses

Situated in one of the wettest climates in America, Houston, TX has had a long history of heavy rains and unprecedented floods. Unfortunately, floods have become more common over the last few decades as climate change increases the frequency and intensity of hurricanes around the globe. To complicate matters further, Houston has quickly sprawled to accommodate over 2.5 billion people. Rapid urbanization has rendered the landscape even more susceptible to floods through excess concretization and watershed disturbance. This thesis traces the history of the Bayou City in relation to the damages caused by Hurricane Harvey. By mapping out the original …


Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen Jan 2019

Island Invasion: The Silent Crisis In Hawaii, Sophia Janssen

Pomona Senior Theses

Keeping out invasive species may, upon first review, seem like a trivial environmental cry from ecologists and deep environmentalists; a belated wish to return to an undeveloped world where nature was pristine. However invasive species create problems that impact all of us and can have far more severe consequences than changing a stunning landscape. These problems are heightened in islands like Hawaii, where the fragile ecosystems have developed over centuries of evolution and adaptation. The introduction of a disease-carrying mosquito can put the people of Hawaii at risk to many vector-born illnesses and create an epidemic, taking human life. The …


Giardia Lamblia Growth In Viscoelastic Fluids, Kelly Watanabe Jan 2019

Giardia Lamblia Growth In Viscoelastic Fluids, Kelly Watanabe

CMC Senior Theses

Giardia lamblia is a single-celled protozoan parasite that when ingested, causes diarrheal disease and infects 33% of people in developing countries. Previous studies observe Giardia in water-like fluids, but Giardia's infectious environment consists of viscoelastic mucus in the small intestine. Therefore, Giardia was cultured in viscoelastic fluids, and its population growth was observed in vitro. To create shear-thinning viscoelastic fluids, 0.2% and 0.4% long-chain polyacrylamide (LCPAM) was added to cell culture media. Giardia was cultured in control media, 0.2% LCPAM, and 0.4% LCPAM, and population growth was quantitatively determined over time. Increasing LCPAM concentration resulted in a solution with …


Prediction Of The Outcome In Cardiac Arrest Patients Undergoing Hypothermia Using Eeg Wavelet Entropy, Hana Moshirvaziri Jan 2019

Prediction Of The Outcome In Cardiac Arrest Patients Undergoing Hypothermia Using Eeg Wavelet Entropy, Hana Moshirvaziri

CGU Theses & Dissertations

Cardiac arrest (CA) is the leading cause of death in the United States. Induction of hypothermia has been found to improve the functional recovery of CA patients after resuscitation. However, there is no clear guideline for the clinicians yet to determine the prognosis of the CA when patients are treated with hypothermia. The present work aimed at the development of a prognostic marker for the CA patients undergoing hypothermia. A quantitative measure of the complexity of Electroencephalogram (EEG) signals, called wavelet sub-band entropy, was employed to predict the patients’ outcomes. We hypothesized that the EEG signals of the patients who …


Pollinator Power: Supporting Bees Through Ecoregion Specific Planting Guides, Maya Thomas Jan 2018

Pollinator Power: Supporting Bees Through Ecoregion Specific Planting Guides, Maya Thomas

Scripps Senior Theses

The pollination of flowering crops by bees is an invaluable ecosystem service that supports biodiversity and much of the global agricultural system. Pollinators move pollen between the male structures of a plant to the female structures of a plant of the same species. This fertilizes the female plant, which then produces the next generation. This process also provides the pollinator with the nectar or pollen it needs to survive. While some plants transfer pollen through different means, the majority of plants need help from pollinators to reproduce. Depending on the means of pollination, pollination can be classified as abiotic or …


Can A Comprehensive Transition Plan To Barefoot Running Be The Solution To The Injury Epidemic In American Endurance Runners?, Michael A. Scarlett Jan 2018

Can A Comprehensive Transition Plan To Barefoot Running Be The Solution To The Injury Epidemic In American Endurance Runners?, Michael A. Scarlett

CMC Senior Theses

Fossils belonging to the genus Homo, dating as far back as two million years ago, exhibit uniquely efficient features suggesting that early humans had evolved to become exceptional endurance runners. Although they did not have the cushion or stability-control features provided in our modern day running shoes, our early human ancestors experienced far less of the running-related injuries we experience today. The injury rate has been estimated as high as 90% annually for Americans training for a marathon and as high as 79% annually for all American endurance runners. There is an injury epidemic in conventionally shod populations that …


Toric Ideals, Polytopes, And Convex Neural Codes, Caitlin Lienkaemper Jan 2017

Toric Ideals, Polytopes, And Convex Neural Codes, Caitlin Lienkaemper

HMC Senior Theses

How does the brain encode the spatial structure of the external world?

A partial answer comes through place cells, hippocampal neurons which

become associated to approximately convex regions of the world known

as their place fields. When an organism is in the place field of some place

cell, that cell will fire at an increased rate. A neural code describes the set

of firing patterns observed in a set of neurons in terms of which subsets

fire together and which do not. If the neurons the code describes are place

cells, then the neural code gives some information about the …