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Analysis Of Aerosols In The Asian Monsoon Anticyclone As Observed By The Atmospheric Chemistry Experiment, M. Lecours, R. Dodangodage, C. D. Boone, P. F. Bernath Jan 2025

Analysis Of Aerosols In The Asian Monsoon Anticyclone As Observed By The Atmospheric Chemistry Experiment, M. Lecours, R. Dodangodage, C. D. Boone, P. F. Bernath

Chemistry & Biochemistry Faculty Publications

During the Asian summer monsoon season, pollutants from the lower troposphere are transported through deep convection to the upper troposphere and lower stratosphere. Surface pollutants such as CO are transported upward and trapped in the anticyclone during this unique atmospheric phenomenon. Associated with the anticyclone is a layer of enhanced aerosols located near the tropopause often referred to as the Asian tropopause aerosol layer (ATAL). The chemical and physical properties of aerosols in the ATAL are not yet fully understood as direct observations of the aerosols are limited. The Atmospheric Chemistry Experiment (ACE) is a satellite mission that provides high-resolution …


From Biophysics To Cellular Function: Neural Telcs-Membrane-Anions Capacitor Transmembrane Potential, James Weifu Lee Jan 2025

From Biophysics To Cellular Function: Neural Telcs-Membrane-Anions Capacitor Transmembrane Potential, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Based on the transmembrane-electrostatically localized protons/cations charges (TELCs) theory, neural transmembrane potential including both resting and action potential is now well elucidated as the voltage contributed by the TELCs-membrane-anions capacitor biophysics in a neuron. Accordingly, neural transmembrane potential has an inverse relationship with TELCs surface density, which may represent a substantial progress in bettering the fundamental understanding of neuroscience. In this article, I will present a review on the latest development of the TELCs neural transmembrane potential theory and address Silverstein’s interesting arguments regarding the TELCs model that may constitute a complementary development to both the Hodgkin-Huxley classic cable theory …


Metathesis Or Isomerization: Counteranion Directed Reactivity Of Grubbs I, Paul D. Miller, Joe B. Calkins, Craig A. Bayse, Trandon A. Bender Jan 2025

Metathesis Or Isomerization: Counteranion Directed Reactivity Of Grubbs I, Paul D. Miller, Joe B. Calkins, Craig A. Bayse, Trandon A. Bender

Chemistry & Biochemistry Faculty Publications

Catalytic isomerization of alkenes has garnered interest for many years, but there are remaining challenges when it comes to thermodynamic selectivity and uncontrolled isomerization. Nonbiased substrates, be it sterically or thermodynamically, remain challenging for many catalysts, with a few examples available in the more modern literature. Herein, we present the controlled isomerization of linear alkenes with a cocatalytic mixture of commercially available catalyst and reagents: Grubbs I, tris(pentafluorophenyl)borane, and triethylsilane. DFT calculations indicate that an observed alkylidyne hydride intermediate is in rapid equilibrium with an alkylidene that binds the alkene substrate. This combination results in a pi-acidic metal and a …


Stack Bonding In Pentacene And Its Derivatives, Craig A. Bayse Jan 2025

Stack Bonding In Pentacene And Its Derivatives, Craig A. Bayse

Chemistry & Biochemistry Faculty Publications

Understanding the nature of π-stacking interactions is important to molecular recognition, self-assembly, and organic semiconductors. The stack bonding order (SBO) model of π-stacking has shown that the conformations of dimers occur when the combinations of monomer MOs are overall stack bonding in character. DFT calculations show that minima found on the potential energy surface for the π-stacked dimers of pentacene and perfluoropentacene occur when the dimer MOs are constructed from combinations of monomer MOs with an allowed SBO. An ex-amination of the MOs of π-stacked dimers extracted from X-ray structures of alkynyl derivatives like TIPS-pentacene pack at one or more …


Molecular Characterization Of Humic And Fulvic Acids On Watterlogged And Well-Drained Amazonian Podzols, Amanda M. Tadini, Aleksandar I. Goranov, Stéphane Mounier, Débora M.B.P. Milori, Célia R. Montes, Patrick G. Hatcher Jan 2025

Molecular Characterization Of Humic And Fulvic Acids On Watterlogged And Well-Drained Amazonian Podzols, Amanda M. Tadini, Aleksandar I. Goranov, Stéphane Mounier, Débora M.B.P. Milori, Célia R. Montes, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The Amazon rainforest is the largest tropical rainforest in the world. Amazonian Podzol soils, characteristic of this region, are known to store substantial amounts of organic carbon in both their surface and deep horizons. Despite decades of research, the molecular-level composition of these soils remains uncharacterized. This study addresses this knowledge gap by employing ultrahigh resolution mass spectrometry, namely, Fourier transform–ion cyclotron resonance–mass spectrometry (FT-ICR-MS), to determine the molecular composition of humic acid (HA) and fulvic acid (FA) fractions from two Amazonian Podzol profiles of varying levels of groundwater exposure (waterlogged vs well-drained). In the waterlogged soil compounds containing nitrogen, …


Protonic Capacitor Cell Energetics: Transmembrane-Electrostatically Localized Protons/Cations, James Weifu Lee Jan 2025

Protonic Capacitor Cell Energetics: Transmembrane-Electrostatically Localized Protons/Cations, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

The transmembrane-electrostatically localized protons/cations charges (TELPs/TELCs) theory can serve as a theoretical framework to better explain cell electrophysiology and elucidate bioenergetic systems including both delocalized and localized protonic coupling. According to the TELCs model, the excess positive charges of TELCs at one side of the membrane are balanced by the excess negative charges of transmembrane-electrostatically localized hydroxides anions (TELAs) at the other side of the membrane. Through the TELCs-membrane-TELAs capacitor model, the energetics of oxidative phosphorylation have recently been better elucidated in mitochondria and alkalophilic bacteria, leading to the identification of a novel Type-B energetic process. Both the TELCs model …


Deciphering The Chemistry Of Condensed Aromatic "Black" Carbon And Nitrogen In Amazonian Anthrosols, João Vitor Dos Santos, Aleksandar I. Goranov, Laís G. Fregolente, Marcia C. Bisinoti, Zhenhuan Sun, Klaus Schmidt-Rohr, Patrick G. Hatcher Jan 2025

Deciphering The Chemistry Of Condensed Aromatic "Black" Carbon And Nitrogen In Amazonian Anthrosols, João Vitor Dos Santos, Aleksandar I. Goranov, Laís G. Fregolente, Marcia C. Bisinoti, Zhenhuan Sun, Klaus Schmidt-Rohr, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

Amazonian anthrosols are renowned for their high fertility and dark color, properties primarily attributed to the abundance of condensed aromatic carbon (ConAC) in the soil organic matter. ConAC, commonly referred to as black carbon, play a key role in the stability and nutrient retention of these soils. However, the processes governing the formation of ConAC and its transformation into oxygenated derivatives remain poorly understood. In this study, we used multiple analytical platforms to investigate the chemistry of ConAC-rich humic acids (HA) extracted from Terra Mulata de Indio, a type of Amazonian anthrosol. The results reveal that ConAC are predominantly …


Formation Of Pyramidal Palladium Enhanced By B(C₆F₅)₃ Additive Enabling Selective Alkene Monoisomerization, Paul D. Miller, Trandon A. Bender Jan 2025

Formation Of Pyramidal Palladium Enhanced By B(C₆F₅)₃ Additive Enabling Selective Alkene Monoisomerization, Paul D. Miller, Trandon A. Bender

Chemistry & Biochemistry Faculty Publications

The addition of a strong Lewis acid, tris(pentafluorophenyl)borane, facilitates the reduction of Pd(cod)Cl₂ with Et₃SiH to form palladium nanoparticles in organic solvents. It was found that these palladium nanoparticles are capable of selective monoisomerization of linear alkenes. This heterogeneous palladium catalyst is tolerant of a wide variety of functional groups, confirmed by substrate and robustness screenings. It is also possible to utilize poly(methylhydro)siloxane, an industrial waste byproduct, as the reductant to enable similar isomerization chemistry.


Experimental Demonstration And Study Of Transmembrane-Electrostatically Localized Protons Prevail, James Weifu Lee Jan 2025

Experimental Demonstration And Study Of Transmembrane-Electrostatically Localized Protons Prevail, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

In this review in relation to some interesting arguments from Silverstein, it is now reaffirmed that the experimental demonstration of transmembrane-electrostatically localized protons (TELPs) was successfully accomplished through 1) using an aluminum film as a TELPs sensor in a biomimetic anode water-membrane-water cathode system, 2) analyzing the water-electrolysis current curve, and 3) measuring bulk liquid phase pH. Formation of induced TELPs was subsequently discovered in an anode water-membrane-water-membrane-water cathode system. The discovery of induced TELPs enabled clean experimental tests on the cation-TELPs exchange process by using sodium bicarbonate or potassium bicarbonate solution in the central liquid chamber. The sodium/TELPs exchange …


Application Of Telc Model To Better Elucidate Neural Stimulation By Touch, James Weifu Lee Jan 2025

Application Of Telc Model To Better Elucidate Neural Stimulation By Touch, James Weifu Lee

Chemistry & Biochemistry Faculty Publications

Aim: This study is to better understand how the transient ion transport activity of touch receptors could change the graded potential to stimulate an action potential firing.

Methods: The latest transmembrane-electrostatically localized protons/cations charges (TELC) theory is employed for numerical analysis to calculate the neural touch signal transduction responding time required to fire an action potential spike.

Results: A neural action potential spike was constructed successfully using newly developed time-dependent TELC-based neural transmembrane potential integral equations (Equations 5, 6, and 7). The results explicated that the TELC curve has an inverse relationship with neural transmembrane potential since its curve appears …


The B³Π–A³Δ And B³Π–X¹Σ+ Band Systems Of Zro, Manish Bhusal, Peter F. Bernath, Jacques Liévin, Léo Lavy Jan 2025

The B³Π–A³Δ And B³Π–X¹Σ+ Band Systems Of Zro, Manish Bhusal, Peter F. Bernath, Jacques Liévin, Léo Lavy

Chemistry & Biochemistry Faculty Publications

The zirconium oxide (ZrO) b³Π–a³Δ system is a prominent source of opacity in the atmospheres of S-type stars in the near-infrared region. The emission spectra of ZrO, obtained at the National Solar Observatory located at Kitt Peak in Arizona, have been utilized to analyze this band system. A reanalysis of the 0–0 vibrational band of the b³Π–a³Δ transition has been carried out. For the first time, the vibrational bands with 1 ⩽ v ′ ⩽ 3 and v″ ≤ 4 for the same electronic transition have been rotationally analyzed using PGOPHER. Additionally, the 0–0 and 1–1 bands of the spin-forbidden …


Identification Of Π-Stacking Motifs In Naphthalene Diimides Via Solid-State Nmr, Jennifer E. Mejia, Hannah E. Butler-Au, Nalaya E. Thompson, Karcher D. Goodman, Elizabeth R. Zengel, Robert D. Pike, Jingdong Mao, Craig A. Bayse Jan 2025

Identification Of Π-Stacking Motifs In Naphthalene Diimides Via Solid-State Nmr, Jennifer E. Mejia, Hannah E. Butler-Au, Nalaya E. Thompson, Karcher D. Goodman, Elizabeth R. Zengel, Robert D. Pike, Jingdong Mao, Craig A. Bayse

Chemistry & Biochemistry Faculty Publications

Organic electronics, featuring π-conjugated small molecules and polymers, have gained significant attention for their potential in flexible, lightweight devices. However, characterization of the ordered, π-stacking domains within these materials using microscopy or X-ray diffraction (XRD) is challenging with complex systems or when crystallography is impractical. This study applied 1D ¹³C multiple cross-polarization magic angle spinning (multiCP/MAS) and 2D ¹H-¹³C heteronuclear correlation (HetCor) solid-state nuclear magnetic resonance (ssNMR) to systematically characterize π-stacking motifs in a series of N,N'-dialkyl naphthalene diimides (NDIs). These techniques were shown to distinguish between the electronic environments attributed to different π-stacking motifs adopted in these NDIs, such …


Assemblage Structure Of Large Carnivorous Coral Reef Fishes At Shallow And Mesophotic Depths In Two Of The Largest And Most Isolated Marine Protected Areas In The Philippines, Rene A. Abesamis, Mikaela L. Salvador, Ryan Murray, Kymry Delijero, Segundo F. Conales, Jean T. Utzurrum, Christopher E. Bird, David T. Gauthier Jan 2025

Assemblage Structure Of Large Carnivorous Coral Reef Fishes At Shallow And Mesophotic Depths In Two Of The Largest And Most Isolated Marine Protected Areas In The Philippines, Rene A. Abesamis, Mikaela L. Salvador, Ryan Murray, Kymry Delijero, Segundo F. Conales, Jean T. Utzurrum, Christopher E. Bird, David T. Gauthier

Biological Sciences Faculty Publications

Overfishing remains a threat to coral reef fishes globally, with large carnivores often the most vulnerable. Marine protected areas (MPAs) can restore fish populations and biodiversity, but their impact has been understudied in mesophotic coral ecosystems (MCEs – extensions of shallow reefs from 30 to 150 m). We analyzed baited remote underwater videos recorded in 2016 to investigate the assemblage structure of large carnivorous fishes at shallow (4–12 m) and mesophotic (45–96 m) depths in two of the largest and most isolated MPAs in the Philippines: Tubbataha Reefs Natural Park (TRNP), a fully no-take MPA enacted in 1988; and Cagayancillo, …


Building Heat-Resilient Caribbean Reefs: Integrating Thermal Thresholds And Coral Colonies Selection In Restoration, Macarena Blanco Pimentel, Johanna Calle-Triviño, Daniel J. Barshis, Sancia E. T. Van Der Meij, Megan K. Morikawa Jan 2025

Building Heat-Resilient Caribbean Reefs: Integrating Thermal Thresholds And Coral Colonies Selection In Restoration, Macarena Blanco Pimentel, Johanna Calle-Triviño, Daniel J. Barshis, Sancia E. T. Van Der Meij, Megan K. Morikawa

Biological Sciences Faculty Publications

Caribbean reefs face increasingly frequent and intense bleaching events, adding to the numerous other threats impacting these ecosystems. Addressing these challenges requires global action to reduce climate drivers, along with local efforts like reef restoration. Active restoration using thermotolerant coral colonies offers a potential strategy to alleviate these impacts; however, gaps remain in identifying context-specific temperature thresholds to guide colony selection and standardize thermotolerance assessment methods. This study addressed these gaps in two phases. First, by determining practical thresholds to differentiate species responses to heat stress; and second, by developing a framework to identify and prioritize resilient colonies for restoration. …


Oxidation Camouflages Terrestrial Organic Matter To Appear Marine-Like, Aleksandar I. Goranov, Susan J. Carter, Ann Pearson, Patrick G. Hatcher Jan 2025

Oxidation Camouflages Terrestrial Organic Matter To Appear Marine-Like, Aleksandar I. Goranov, Susan J. Carter, Ann Pearson, Patrick G. Hatcher

Chemistry & Biochemistry Faculty Publications

The export of terrestrial organic matter (TOM) to the ocean has been traditionally viewed to be minimal or only of significance in near-coastal continental margins. The broadly accepted explanation for the widespread loss of terrestrial lignin biomarkers and apparent disappearance of the <-25‰ stable carbon isotopic signature (δ¹³C) of TOM is that TOM is almost fully degraded before reaching the open ocean. Oceanic carbon (δ¹³C value ≥ -22‰) is therefore thought to be derived primarily from algae. However, an alternative explanation for the different molecular and δ¹³C signatures in terrestrial and marine environments may be that oxidative processing transforms TOM to appear marine-like. To test this hypothesis, we subjected eight TOM samples to a strong oxidation gradient. At carbon losses typical of TOM degradation during transport and sedimentation (above 60%), the differentiators of provenance disappeared, leaving a residue that was marine-like both chemically (aliphatic- and nitrogen-rich) and isotopically (δ¹³C enrichment of 4 to 9‰). This challenges the validity of conventional two-endmember mixing models, suggesting that a much larger fraction than previously estimated of the organic matter found in the ocean may originate from terrestrial sources, impacting global models of carbon cycling and sequestration.


Amphiphilic Tripodal Metalloligands: Synthesis, Coordination Chemistry And Preliminary Catalysis, Austin W. Medley, Paul D. Miller, Craig A. Bayse, Robert D. Pike, Trandon A. Bender Jan 2025

Amphiphilic Tripodal Metalloligands: Synthesis, Coordination Chemistry And Preliminary Catalysis, Austin W. Medley, Paul D. Miller, Craig A. Bayse, Robert D. Pike, Trandon A. Bender

Chemistry & Biochemistry Faculty Publications

Triscatecholate binding has been widely studied in the context of biological systems, supramolecular chemistry, and weak aggregate interactions. However, the utilization of the triscatecholate binding motif for the preparation of metalloligands remains unexplored. Herein, we report the synthesis, structural characterization, and functional studies of a triscatecholate ligand with an appended pyridyl residue as a candidate for such applications. Our findings reveal that the selective formation of cis-triscatecholate-based metalloligands is influenced by electronic effects on the catecholate anions, enabling the targeted synthesis of Al(III), Ga(III), and In(III) triscatecholate metalloligands capable of binding Zn(II) and Ru(II) at the appended pyridyl moiety for …


Twenty Years Of Global Stratospheric Fluorine Inventories From Atmospheric Chemistry Experiment Fourier Transform Spectrometer (Ace-Fts) Measurements, N. Raymond, P. Bernath, C. Boone, M. Chipperfield Jan 2025

Twenty Years Of Global Stratospheric Fluorine Inventories From Atmospheric Chemistry Experiment Fourier Transform Spectrometer (Ace-Fts) Measurements, N. Raymond, P. Bernath, C. Boone, M. Chipperfield

Chemistry & Biochemistry Faculty Publications

We present fluorine inventories calculated for twenty years (2004–2023) and five latitude bands (82°–60°N, 60°–30°N, 30°N–30°S, 30°–60°S, and 60°–82°S) at altitudes from the surface up to 55 km. The inventories were calculated using the Atmospheric Chemistry Experiment Fourier transform spectrometer (ACE‐FTS) version 5.2 retrievals of the volume mixing ratios (VMRs) of 15 fluorine‐containing species. Of these 15 species, 3 are product gases: HF, COF₂, COCIF, and 12 are source gases: SF₆, PFC-14 (CF₄), CFC-11 (CCl₃F), CFC-12 (CCl₂F₂), CFC-113 (CCIF₂CCl₂F), HCFC-22 (CHF₂CL), HCFC-141b(C₂H₃Cl₂F), HCFC-142b ( …


Experimental Evaluation Of Corrosion Of Strands And Wires To Estimate Corrosion Rate In Grout And Concrete, Dipendra Shrestha Jan 2025

Experimental Evaluation Of Corrosion Of Strands And Wires To Estimate Corrosion Rate In Grout And Concrete, Dipendra Shrestha

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Premature failure of prestressed and post-tensioned concrete structures is frequently caused by undetected corrosion of prestressing steel. Although extensive research has addressed corrosion rates in conventionally reinforced concrete, the interpretation of non-destructive parameters, such as half-cell potential (HCP) and concrete/grout resistivity, for estimating corrosion rates in prestressing steel are not adequately investigated.

This research experimentally evaluates chloride-induced corrosion of prestressing steels to establish material-specific relationships between in-situ measurable parameters and corrosion rate. Thirty-six macrocell specimens incorporating plain wires, indented wires, and seven-wire strands in structural concrete and commercial post-tensioning grout- half with pre-formed surface cracks, were subjected to accelerated cyclic …


Fire History, Ecological History, And Historical Human-Environment Interactions In The Northern Great Plains, James Victor Benes Jan 2025

Fire History, Ecological History, And Historical Human-Environment Interactions In The Northern Great Plains, James Victor Benes

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation explores the spatiotemporal signatures of fire in North American grassland ecosystems. In three chapters, I explore different aspects of fire history in the northern Great Plains. Chapter 1 is an introduction. Chapter 2 focuses on the Euro-American Settlement Period (ca. 1850–1950 C.E.). Fire histories from six different lakes in the Nebraska Sandhills are compared with two periods of historic drought and the establishment of United States Post Offices. Five of the six records show increased levels of biomass burning during the initial phases of Euro-American Settlement. Chapter 3 is a long-term (ca. 15,000 years), high-resolution fire history and …


Exploring Factors Influencing Student Growth In Mathematics: Elementary Teacher Instructional Practices, Beliefs, And Professional Development Experiences, Marni E. Driessen Jan 2025

Exploring Factors Influencing Student Growth In Mathematics: Elementary Teacher Instructional Practices, Beliefs, And Professional Development Experiences, Marni E. Driessen

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

High-quality student learning experiences in mathematics rely on effective teaching. This mixed methods study investigates how elementary teachers’ instructional practices, beliefs about mathematics teaching and learning, and professional development experiences relate to student mathematics growth in a large urban district. Quantitative survey data were analyzed to examine relationships among these factors and student growth outcomes, while qualitative data complemented and deepened the measurable findings. This study builds on prior research on instructional practices and professional development effectiveness by integrating constructs typically examined separately and identifying multiple teacher-related factors that distinguish classrooms with high student growth from those with low growth. …


Scientific Writing: A Guide From Data To Draft, Kristin M. Klucevsek Jan 2025

Scientific Writing: A Guide From Data To Draft, Kristin M. Klucevsek

Open Education Materials

Textbook for ENGL302W (Scientific Writing)

CC BY-NC-SA (2025)


Algorithms In Finance: Balancing First Amendment Protections And Regulation, Yusraa Tadj Jan 2025

Algorithms In Finance: Balancing First Amendment Protections And Regulation, Yusraa Tadj

Fordham Journal of Corporate & Financial Law

As algorithms become a function of decision-making in the financial sector, policymakers, the judiciary, and academics grapple with regulatory questions. With the increased reliance on algorithms in finance, the Securities and Exchange Commission (SEC) proposed a rule to mitigate potential conflicts of interest that can arise out of financial firms using algorithms. Algorithm users, including financial firms, are finding novel ways to protect algorithm use, such as by offering them First Amendment protections.

This Note considers to what extent algorithms can be considered protected speech amidst the complexity of algorithms and relationship within the financial sector. The Note argues that …


Assessing Tidal Energy Potential In The Visayas: Viability Of The San Bernardino, San Juanico, And Cebu Straits, Justin Kyle O. Ricafort, King Harold A. Recto Jan 2025

Assessing Tidal Energy Potential In The Visayas: Viability Of The San Bernardino, San Juanico, And Cebu Straits, Justin Kyle O. Ricafort, King Harold A. Recto

Sustainability, Disaster Science and Energy

By laying the groundwork for sustainable tidal energy infrastructure, this study contributes to advancing the Philippines' renewable energy portfolio and supports the global transition to clean energy solutions. With the country's extensive coastline and rising energy demands, tidal energy presents a largely underutilized yet promising resource that can address both local and global energy challenges. Tidal energy is highly predictable, stable, and environmentally friendly, offering a reliable alternative to conventional energy sources like coal and natural gas, which are often subject to price volatility and environmental concerns. The study focuses on the Visayas region, a prime candidate for tidal energy …


Valuating The Impact Of Unexploded Ordnance (Uxo) In Savannakhet, Laos Through Ecosystem Services Assessments, Nathan Lu Jan 2025

Valuating The Impact Of Unexploded Ordnance (Uxo) In Savannakhet, Laos Through Ecosystem Services Assessments, Nathan Lu

Pitzer Senior Theses

Unexploded ordnance (UXO) impact on countries is not well-documented, since post-war surveys or data collection are often hindered by a lack of appropriate funding and reparation. In Laos, UXO has hardly been cleared since 1964 and thus leaves room for spatially and temporally analyzing the severity of environmental and economic degradation in the area. This study uses the framework of ecosystem services, particularly carbon stock, as a way to provide quantitative metrics of impact to local governments and stakeholders. Through remote sensing data in Savannakhet Province, evidence-based land-use change data was spatially analyzed with geocoded UXO bomb mission locations and …


Untangling The Classification Of Surfaces: An Accessibility-Centered Perspective On Topology, Charlotte N. Richards Jan 2025

Untangling The Classification Of Surfaces: An Accessibility-Centered Perspective On Topology, Charlotte N. Richards

Pitzer Senior Theses

Mathematics has clear benefits in education, from preparing students for future careers to teaching them how to problem-solve. While mathematics achievement has been falling in recent decades, students claim that the problem is not the mathematics itself, but the ‘boring’ classroom material that feels removed from real life. More advanced mathematics topics, such as topology, could offer a solution, as their applications lie in countless fields. However, topology has been restricted to upper-level mathematics, disregarding the potential benefits of making this material broadly reachable for a junior high-school audience. In this paper, we analyze five different proofs of the theorem …


The Requirements Of A Nuclear Propulsion System For The Human Exploration Of Mars, Scotia Rollins Jan 2025

The Requirements Of A Nuclear Propulsion System For The Human Exploration Of Mars, Scotia Rollins

Pitzer Senior Theses

This thesis investigates the propulsion requirements for a crewed mission to Mars, focusing on how mission architecture, particularly the choice between opposition- and conjunction-class trajectories, influences the selection between nuclear thermal propulsion (NTP) and nuclear electric propulsion (NEP). By applying the Tsiolkovsky rocket equation, the Delta-V (∆V) needed for efficient interplanetary transfers is shown to exceed the performance limits of chemical propulsion, motivating the need for nuclear alternatives. An engineering comparison of NTP and NEP systems evaluates key parameters including specific impulse, thrust, propellant mass fraction, system mass, and power-to-mass ratios. NTP provides high thrust but moderate efficiency, making it …


Development Of A Swpbis Fidelity Tool For Front-Line Intervention Agents, Courtney A. Sowle Jan 2025

Development Of A Swpbis Fidelity Tool For Front-Line Intervention Agents, Courtney A. Sowle

All Graduate Theses, Dissertations, and Other Capstone Projects

SWPBIS is a commonly used EBP that provides a continuum of support across three tiers of prevention (Farkas et al., 2012; Mercer et al., 2017). It is known that implementation of SWPBIS with high levels of fidelity has resulted in positive outcomes for students within that system (Farkas et al., 2012). While systems may report high fidelity of implementation of SWPBIS within their system, these reports may not be representative of how an evidenced-based practice (EBP) is implemented by frontline intervention agents and instead is likely more representative of the subjective perceptions of PBIS team members and external coaches (Reinke …


The Relationship Between The U.S Stock Market And Energy Commodities, Griffin Seel, Mari Arroyave, Jack Griffin, James Murphy Jan 2025

The Relationship Between The U.S Stock Market And Energy Commodities, Griffin Seel, Mari Arroyave, Jack Griffin, James Murphy

High Impact Practices Student Showcase Spring 2025

This project began with the goal of finding the predictive power of oil and natural gas on the U.S. stock market. We gathered and used government-issued data on foreign oil imports volume and grade, domestic crude oil prices, domestic natural gas prices and volume, and S&P 500 prices from the 2023 fiscal year. We wrote a program in R that used several different criteria to give us the relationship between the above variables in a simple, optimal, mathematical model. We also used methods from our course such as the Box Cox transformation test to refine our variables. Ultimately, we found …


A Study In The Student Experience Of Care – What It Looks, Sounds, And Feels Like For Students In A Rural Public High School, Steven Mark Chamberlin Jan 2025

A Study In The Student Experience Of Care – What It Looks, Sounds, And Feels Like For Students In A Rural Public High School, Steven Mark Chamberlin

Doctoral Dissertations

Students' voices are essential to understanding their perceptions, experiences, and viewson care. Many schools prioritize standardized test outcomes over individual care for each child, which leads to disengagement and a lack of agency. Students who feel cared for tend to achieve greater success in school.

This question guided the inquiry: How do students perceive, experience, and understandcare in their secondary school in New Hampshire? Twelve individual interviews were conducted with students who had varying degrees of academic success and special education identification.

The findings led to the development of a preliminary model of care that establishesschool culture as the foundation …


The Impacts Of Social Media On Teacher Environment Perceptions, Victoria Puglia Jan 2025

The Impacts Of Social Media On Teacher Environment Perceptions, Victoria Puglia

Doctoral Dissertations

Social media significantly influences teachers’ perceptions of their professional environment, shaping job satisfaction, respect, autonomy, and professional support. This dissertation, split into three articles, investigates how exposure to positive, negative, or mixed social media posts impact these perceptions, addressing concerns surrounding teacher well-being and attrition in K-12 education. The study began with a literature review in Article 1 to establish a theoretical framework, followed by a series of validation steps to refine a survey instrument aligned with teaching perception constructs in Article 2. The final survey was administered to 406 K-12 teachers across the United States in Article 3, using …