Physiology Commons^™

Organic Geochemical Evidence For Life In Archean Rocks Identified By Pyrolysis-Gc-Ms And Supervised Machine Learning, Michael L. Wong, Anirudh Prabhu, Conel O'D. Alexander, H. James Cleaves Ii, George D. Cody, Grethe Hystad, Marko Bermanec, Wouter Bleeker, C. Kevin Boyce, Andrea Corpolongo, Andrew D. Czaja, Souvik Das, Robert R. Gaines, Daniel D. Gregory, John A. Jaszczak, Emmanuelle J. Javaux, Jaganmoy Jodder, Andrew H. Knoll, Martin Van Kranendonk, Katie M. Maloney, Nora Noffke, Robert Rainbird, Emersyn Slaughter, Eva E. Stüeken, Roger E. Summons, Frances Westall, Jasmina Wiemann, Shuhai Xiao, Robert M. Hazen

OES Faculty Publications

Throughout Earth’s history, organic molecules from both abiogenic and biogenic sources have been buried in sedimentary rocks. Most of these organic molecules have been significantly altered by geologic processes through deep time. Nonetheless, the nature and distribution of those ancient fragmentary organic remains have the potential to reveal diagnostic biomolecular information after billions of years of burial. Here, we analyzed 406 fossil, modern biological, meteoritic, and synthetic samples using pyrolysis gas chromatography and mass spectrometry. We explored these analytical data via supervised machine-learning methods to discriminate samples of biogenic vs. abiogenic origin, plant vs. animal phylogenetic affinity, and photosynthetic vs. …

Traction Force Microscopy Using An Epifluorescence Microscope: Experimental Considerations And Caveats, Zaria Booth, Mazen Mezher, Rudra Patel, Venkat Maruthamuthu

Mechanical & Aerospace Engineering Faculty Publications

Forces exerted by cells due to their internal contractility play fundamental roles in a host of processes, including adhesion, migration, survival and differentiation. Traction force microscopy (TFM) enables the determination of forces exerted by cells or cell collectives on their environment, which is typically taken to be an extra-cellular matrix (ECM)-coated substrate. Sample preparation for TFM involves the plating of cells onto an environment embedded with fiducial markers. The imaging of these fiducial markers in the presence and absence of the cells then enables calculation of the displacement of localized regions of the environment, and, consequently, the spatial distribution of …

Assessing The Role Of Daily Thermal Fluctuations In The Performance Of Mitochondrial Energy Transduction Of The Centrarchid, Lepomis Cyanellus, Grayson Hofmann

Masters Theses

Freshwater systems are affected by current climate extremes, forcing species found in these systems to withstand drastic changes in temperature. Temperature changes affect these organisms by altering their metabolic rate and energy balance. Increases in temperature can lead to an increase in oxygen consumption, which ultimately increases the need for more energy production. Mitochondrial energy transduction of green sunfish (Lepomis cyanellus) and many other fish species after a thermal insult, has hardly been explored. This study complements the limited research available on mitochondrial function in similar species, as they ignore the possibility of consecutive thermal events, which are …

Racial Health Disparities Among Pregnant Women Of Color In New York City: Biological And Systemic Impacts, Kaylin Peña

Pitzer Senior Theses

Racial Health Disparities Among Pregnant Women of Color in New York City: Biological and Systemic Impacts

Abstract

This thesis aims to explore how racial health disparities, underrepresentation in gynecology, and socioeconomic barriers contribute to adverse pregnancy outcomes among women of color in New York City. Through an interdisciplinary approach that combines resources from medical anthropology and human biology, this research will examine the biological implications of chronic stress, specifically HPA axis dysregulation, and its role in maternal health outcomes. With the idea of intersectionality, as conceptualized by Kimberlé Crenshaw, the study analyzes the various effects of systemic inequities and social …

The Impact Staphylococcus Aureus Has On Conventional And Organic Dairy Herds In New Hampshire And New York, Jacqueline Rose Holmes

Honors Theses and Capstones

Staphylococcus aureus is a potentially virulent bacterium that causes mastitis in dairy cattle. The toxins produced from S. aureus impact host immunity, damage the mammary gland, and can adapt to cause antimicrobial resistance. It is important to manage both organic and conventional farms correctly by practicing proper hygiene while milking and providing a clean environment. There is a significant increase of S. aureus cases on organic farms compared to conventional, so there may be ways in which organic management and treatment options could be altered to reduce economic loss and animal suffering. The thesis focuses on the involvement S. aureus …

The Design Of A Bioinspired Impact Mitigation System Towards The Prevention Of Brain Injuries, Bryce H. Reimer

Master’s Theses

Traumatic brain injuries (TBIs), including concussions and chronic traumatic encephalopathy (CTE), remain a major concern across contact sports, military operations, and transportation. Despite advancements in protective equipment, current strategies often fall short in preventing the mechanical conditions that contribute to long-term neurological damage. This thesis presents the design and validation of a bioinspired impact mitigation system modeled after bighorn sheep horn structures, which have evolved to endure high-energy collisions without apparent brain injury.

Using biomimetic principles, the research integrates experimental and computational methods to evaluate how horn-like geometries reduce impact-induced accelerations. A custom drop tower was built to test dynamic …

Physiological Responses And Plant Trait Interactions With Coastal Dune And Swale Development, Emily C. Riffe

Theses and Dissertations

Vegetation is crucial to coastal ecosystems experiencing climate change and storm-induced disturbance. Plant species interact with the physical environment and are considered “ecosystem engineers.” Sand dunes and barrier islands are at the forefront of climate change impacts as they are barriers that protect landward habitat and communities. Nature based solutions are utilized to protect infrastructure on developed coastlines. Understanding how dominant plant species interact with and alter the physical environment enhances our understanding of the mechanisms of change and consequences to the system. The goal of this research was to quantify physiological and functional trait differences in dominant species found …

Impacts Of Physical Inactivity Models On Endothelial Function: A Systematic Review, Joel E. Harden, J. David Branch, Leryn J. Reynolds

Exercise Science Faculty Publications

Background

Endothelial dysfunction is associated with cardiovascular disease and cardiac events. Numerous studies demonstrate that a reduction in physical activity/exercise levels are associated with poor endothelial function. Yet, these studies use a plethora of models to mimic reduced activity levels which may have widely different results on endothelial function. It is pertinent to collectively review these articles to provide a comprehensive understanding of the impact of reduced activity on vascular health, as endothelial function is one of many factors that influences vascular tone.

Objective

The purpose of this systematic review is to examine and synthesize the current literature regarding the …

Motion Artifacts (Ma) At-Rest In Measured Arterial Pulse Signals: Time-Varying Amplitude In Each Harmonic And Non-Flat Harmonic-Ma Coupled Baseline, Md Mahfuzur Rahman, Mamun Hasan, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

Motion artifacts (MA) cause great variability in a measured arterial pulse signal, and treatment of MA solely as a baseline drift (BD) fails to eliminate its effect on the measured signal. This paper presents a study on the effect of MA at rest (< 0.7 Hz) on measured arterial pulse signals using a microfluidic-based tactile sensor. By taking full account of the dynamic behavior of the transmission path from the true pulse signal in an artery to a measured pulse signal at the sensor, the tissue-contact-sensor (TCS) stack, an analytical model of MA in a measured pulse signal is developed. In this model, the TCS stack is treated as a 1DOF system for its dynamic behavior; MA is quantified as the displacement (i.e., BD) and time-varying system parameters (TVSP) of the TCS stack. The mathematical expression of MA in a measured pulse signal reveals that while BD remains as low-frequency additive noise, TVSP causes time-varying harmonics in a measured pulse signal. Further time-frequency analysis (TFA) of measured pulse signals validates the existence of TVSP and, for the first time, reveals its effect on a measured pulse signal: time-varying amplitude in each harmonic and non-flat harmonic-MA-coupled baseline.

Systematic Review Of Immunohistochemistry Protocols, Arpitha Parthasarathy

Pitzer Senior Theses

Immunohistochemistry (IHC) is an essential technique in biological research that allows for the visualization and localization of proteins within tissue samples. This systematic review analyzes the most effective, efficient and reproducible protocols for IHC. It focuses on three critical steps: freezing, cryosectioning, and staining of skeletal muscle tissues in mice models. A total of 41, 44, and 48 articles on freezing, cryosectioning, and staining techniques, respectively, were analyzed, from reputable sources in biology like PubMed and Web of Science. Results showed the following. For freezing, the use of isopentane combined with liquid nitrogen appeared to be the best method, minimizing …

Improving Glucose Levels In Adults With Type 2 Diabetes, Kaitlin Castillo

Doctor of Nursing Practice (DNP) Scholarly Projects - Archive

Type 2 diabetes is a growing health crisis, posing significant challenges not only to individual well-being but also to healthcare systems' financial sustainability. The prevalence of type 2 diabetes continues to rise annually, contributing to increased medical costs, hospitalizations, and long-term complications. Houston, Texas, has a diabetes prevalence of 13.5%, exceeding the national average of 10%. A clinical gap exists in providers’ ability to prevent and manage type 2 diabetes. Prioritizing prevention, early intervention, and improved patient monitoring can reduce incidence rates, lower healthcare costs, and enhance overall population health. A Plan Do Study Act model was utilized for the …

Rad Reduction Reveals Therapeutic Potential Of Targeting Cardiomyocyte L-Type Calcium Channel Regulation For Heart Failure, Garrett Elmore

Theses and Dissertations--Physiology

Heart failure (HF) is prevalent and is predicted to increase with the aging population. Dilated cardiomyopathy (DCM) is a common cause of systolic HF. Current therapies fail to address principal issues: compromised systolic function and dysfunctional Ca²⁺ handling. No therapeutic approach exists for direct, positive modulation of cardiomyocyte L-type calcium channels (LTCC). RAD (Ras associated with diabetes) is a key regulator of the cardiac LTCC. RAD is a downstream phosphorylated target of the ß-adrenergic receptor (ß-AR)/cAMP/protein kinase A pathway; phosphorylation augments LTCC activity, contributing to chronotropy, inotropy, and lusitropy. RAD overexpression results in LTCC inhibition, whereas knockout positively modulates …

Exploring The Placebo Effect On The Cortisol Stress Response, Povheng Yam

Cal Poly Humboldt theses and projects

The placebo effect is well-studied on pain perception and is often observed to have a pain-reducing effect in patients. A few studies suggest that the placebo effect can influence physiological changes in people. To date, not many studies have examined the placebo effect on stress; thus, the current study explored the placebo effect on participants’ cortisol stress response and self-reported stress while undergoing a modified acute stress task, the Sing-a-Song Stress Test (SSST). The current study includes 44 participants (22 in the control group and 22 in the treatment group). A deceptive stress-reducing tincture (filled with water) was used as …

Testing The Life-History Dependence Of Dietary Restriction Effects On Oxidative Molecular Damage In Hornworms, Fahime Taheri

Masters Theses

DR and ambient temperature are two environmental factors widely implicated in shaping organismal maintenance and longevity through effects on metabolic rate and oxidative damage. This study tests whether DR and reduced body temperature independently or interactively reduce oxidative protein damage in the gut of tobacco hornworm larvae, a short-lived ectotherm whose life history may constrain typical DR responses. Larvae hatched from eggs were allocated to two feeding regimes (AL and DR) and to 20 °C and 30 °C. At a defined endpoint, guts dissected and homogenized, and analyzed for protein carbonyl content and total protein. Protein damage was expressed as …

Menstrual Cycle Phase Effects On Exercise Thermoregulation And Performance In The Heat, Kailei J. Eustis

All Master's Theses

Hormone fluctuations across the menstrual cycle (MC) may influence physiological responses. This study examined whether thermoregulatory measures differ across MC phases, and if these changes impact running performance in the heat. Ten eumenorrheic adults completed two treadmill runs in simulated conditions (wet bulb globe temperature 31.7 ± 1.4°C) during early follicular (EF) and midluteal (ML) phases. First 45min was a constant self-selected light pace followed by a 15min performance test for distance. Core temperature (Tc), mean skin temperature (Ts), heart rate (HR), perceived exertion (RPE), thermal perception (THERM), and comfort perception (COMF) were assessed every 5min. Sweat perception (SP), sweat …

Evaluating Dietary Consequences On Body Mass And Thermal Heat Flux Of North American Bison (Bison Bison) Yearling Heifers, Kendall Marie Wald

Electronic Theses and Dissertations

No abstract provided.

Ceramide Homeostasis In Hepatic Lipid Droplets, Leobarda Robles-Martinez, Kylie H. Morin, Mariana Nikolova‑Karakashian

Physiology Faculty Publications

Almost all eukaryotic cells have the capacity to form lipid droplets (LDs) in conditions of excess energy. Traditionally thought to be just inert fat reservoirs, LDs have recently emerged as important metabolic regulators of cellular stress response that buffer excess free fats and protect cells from lipotoxicity. Ceramide is a bioactive lipid that accumulates in metabolic tissues during fat oversupply. Emerging evidence suggests that sphingolipids and sphingolipid-metabolizing enzymes are found in the LDs and affect LD biogenesis and functions. This article aims to summarize the evidence, delineate some plausible functions of ceramide in hepatic LD biogenesis, and illustrate some of …

A 40-Week Phase 2b Randomized, Multicenter, Double-Blind, Placebo-Controlled Study Evaluating The Safety And Efficacy Of Memantine In Amyotrophic Lateral Sclerosis, Salman Bhai, Todd Levine, Dan Moore, Robert Bowser, Andrew J. Heim, Maureen Walsh, Aziz Shibani, Zachary Simmons, James Grogan, Namita A. Goyal, Raghav Govindarajan, Yessar Hussain, Tania Papsdorf, Tiffany Schwasinger-Schmidt, Nick Olney, Kim Goslin, Michael Pulley, Edward J. Kasarskis, Michael Weiss, Susan W. Katz, Suzan Moser, Duaa Jabari, Omar Jawdat, Jeffrey Statland, Mazen M. Dimachkie, Richard Barohn, Neuromuscular Study Group And Western Als Consortium Memantine Als Study Group

Neurology Faculty Publications

Introduction: Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neurodegenerative disease with no known cure, limited treatment options with minimal benefits, and significant unmet need for disease modifying therapies.

Aims: This study investigated memantine's impact on ALS progression, with an additional focus on the effects of memantine on cognitive and behavioral changes associated with the disease.

Methods: A randomized, double-blind, placebo-controlled clinical trial was conducted from December 2018 to September 2020. ALS patients were enrolled in-person and remotely across 13 sites in the United States. Participants were randomized to memantine (20 mg twice daily) or placebo in a 2:1 ratio …

Metabolic And Barrier Function In Response To Β-Caryophyllene In Intestinal Epithelial Cells, Hannah Scroggins

Theses and Dissertations--Animal and Food Sciences

Butyrate, a short-chain fatty acid, regulates cellular metabolism and energy status in intestinal epithelial cells. β-caryophyllene (BCP) is a plant-derived compound that may provide advantageous effects on intestinal barrier function and nutrient utilization. The goal of this thesis was to investigate the effects of BCP on butyrate utilization and metabolism in intestinal epithelial cells. Throughout this thesis, Caco-2 cells in hanging inserts in multi-well plates were used as a model for the intestinal barrier. One study was conducted to investigate the effect of BCP on butyrate utilization and barrier function in intestinal epithelial cells. A second study aimed to elucidate …

A Decision-Space Model Explains Context-Specific Decision Making, Dirk W. Beck, Cory N. Heaton, Luis D. Davila, Lara I. Rakocevic, Sabrina M. Drammis, Danil Tyulmankov, Atanu Giri, Shreeya Umashankar Beck, Qingyang Zhang, Michael Pokojovy, Kenichiro Negishi, Alexis A. Salcido, Neftali F. Reyes, Andrea Y. Macias, Serina A. Batson, Paulina Vara, Raquel J. Ibáñez Alcalá, Safa B. Hossain, Graham L. Waller, Laura E. O'Dell, Travis M. Moschak, Ki A. Goosens, Alexander Friedman

Mathematics & Statistics Faculty Publications

Optimal decision-making requires consideration of internal and external contexts. Biased decision-making is a transdiagnostic symptom of neuropsychiatric disorders. We created a computational model demonstrating how the striosome compartment of the striatum constructs a context-dependent mathematical space for decision-making computations, and how the matrix compartment uses this space to define action value. The model explains multiple experimental results and unifies other theories like reward prediction error, roles of the direct versus indirect pathways, and roles of the striosome versus matrix, under one framework. We also found, through new analyses, that striosome and matrix neurons increase their synchrony during difficult tasks, caused …