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Take A Video Tour Of Shoals Marine Laboratory, Scott Ripley

UNH Today Archive

No abstract provided.

Factors Contributing To The Demographic Cliff: More U.S. Women Of Childbearing Age, But Fewer Have Given Birth, Kenneth M. Johnson

Carsey Publications

In this brief, author Kenneth Johnson reports that in 2024 there were 5.7 million more childless women of prime child-bearing age than would have been expected given fertility patterns prior to the Great Recession, up from 2.1 million in 2016 and 4.7 million in 2022. There are 4 million more women aged 20–39 than in 2006, but 7 million fewer have given birth. The shift in fertility patterns has resulted in 11.8 million fewer babies in the past 17 years.

Fertility rate declines were greatest among women under 30, where childless rates increased the most. Childless rates increased modestly among …

Nsf Mid-Career Grant Backs Unh Research Into Why Rural Youth Stay — Or Leave, Aaron Sanborn

UNH Today Archive

No abstract provided.

Gilman Scholarships To Send Unh Students To Five Continents, Keith Testa

UNH Today Archive

No abstract provided.

“Lead”Ing Industrial Science: Studying Occupational Lead Poisoning In The Early 20th Century, Rebekah E. Dreyer-Rowe

Master's Theses and Capstones

Lead was essential to the creation and coalescence of industrial hygiene as a discipline in the United States from its early days in the 1910s through the 1930s when the first professional associations of industrial hygiene were formed. In the early years, Alice Hamilton was central to the burgeoning field, and her seminal study on lead poisoning in Illinois industries thrust both her and her methods into the spotlight. Industrial hygienists of her generation followed her methods and came away with similar conclusions: that occupational diseases were rampant in the US, even if few people were studying them. In the …

Innocent Fun Or Unhealthy Habit: What's Your Game? Personality And Engagement With Video Games, Derrick Angier

Doctoral Dissertations

This thesis reports two exploratory studies of similar design, both of which investigated which gamers might be at risk for problematic or aggressive gaming. In both Study 1 (N = 480) and Study 2 (N = 761), which served as a replication, four composite scores representing participants’ personality attributes were created from big traits of the HEXACO—Honesty-Humility, Emotionality, Extraversion, Agreeableness, Conscientiousness, and Openness, a people-centered intelligence—personal intelligence—and motives for gaming. These composite scores and the subordinate individual variables were used to predict lifespace measures of unhealthy/healthy gaming behaviors and aggressive/pro-social in-game interactions. Lifespace scales capture a person’s reports of their …

Synthetic And Analytical Methods For Metal Targeting Peptides For The Sensing And Removal Of Metals Across Various Matrices, Emily Andrews

Doctoral Dissertations

Metal chelators developed from peptides boast favorable attributes such as low toxicity, ease of synthesis, and high tunabilty to the target metal ion. It is for these reasons that peptides are used for metal sensing and sequestration in the body and environment. Herein, two unique sets of metal targeting peptides are discussed: (1) bifunctional Szeto-Schiller and Kelley peptide probes to signal the presence of and remove labile iron (Fe2+ and Fe3+) in the mitochondria, to mitigate the progression of Ferroptosis and (2) Pb2+ targeting peptides designed to exist in aqueous environments for the removal of toxic lead ions from waterways. …

Multiscale Modeling And Analysis Of Biomedically Relevant Uhmwpe-Based Composite Materials, Stanislav Buklovskyi

Doctoral Dissertations

The development of ultra-high-molecular-weight-polyethylene (UHMWPE) based composite materials continues to present significant opportunities in biomedical engineering, particularly in joint arthroplasty and implant technologies. As applications expand, the need for accurate modeling of microstructure–property relationships to guide informed material design and manufacturing decisions is increasing. This dissertation presents a multiscale numerical modeling framework informed by X-ray micro-computed tomography (μCT) data to corelate the effective mechanical, thermal, and electrical properties of biomedically relevant composite systems with their microstructure.

Two material systems are considered: UHMWPE reinforced with conductive carbon black (CB) nanoparticles, and porous UHMWPE with two processes of pores generation. For CB/UHMWPE …

From Structure To Specificity: Biophysical Characterization Of Functional Interfaces In Protein Systems, Logan M. Brown

Doctoral Dissertations

Proteins are nature’s dynamic molecular machines, operating across a spectrum from highly ordered scaffolds to intrinsically disordered systems, and executing functions that depend on both precise structures and conformational flexibility. Yet, the mechanistic rules linking sequence, structure, and activity particularly in disordered proteins and specialized functional adaptations remain incompletely understood. This dissertation addresses that gap by integrating structural biology, biophysics, and protein engineering to dissect molecular recognition, stability, and function across three diverse yet thematically connected protein systems. Building on this understanding of protein structure and function, the following four projects apply these concepts to address diverse biological questions, ranging …

Evaluating The Effects Of Agricultural Management Practices On Beneficial Arthropod Communities, Isaac Newton Ativor

Doctoral Dissertations

Arthropods provide essential ecosystem services to our agricultural landscapes. These ecosystem services include biological control of pest organisms, including weed seeds, and plant pollination. Concerningly, however, there has been a global decline in insect populations over the last decade, a major cause of which is agricultural intensification. Previous research has demonstrated that agricultural management practices can strongly influence the species composition and abundance of arthropod communities, and therefore presumably the ecosystem services or disservices these organisms provide; however, our understanding of these interactions remains limited. I conducted three studies to investigate whether agricultural practices common in annual row crop (tillage …

Interpolated Factored Green's Function (Ifgf) Method Of Acceleration For Electromagnetic Scattering Off Of A Perfectly Electrically Conducting Surface, Mathew D'Amico

Doctoral Dissertations

Boundary integral equation (BIE) methods are advantageous in scattering problems due to their reduction of the problem's dimensionality as well as their automatic satisfaction of far-field radiation conditions. Specifically, for electromagnetic scattering off of perfectly electrically conducting (PEC) geometries, we are concerned with the magnetic field integral equation (MFIE). Typically, BIE implementation is iterative, with each direct integration requiring $\mathcal{O}(N^2)$ operations for a grid size $N$. For large $N$, this incurs very large computation times. To date, all existing methods that reduce the asymptotic operational complexity of evaluating the MFIE integral to $\mathcal{O}(N\log N)$ rely on use of the Fast …

Reentry, Justice Involvement, And Evolving Perspectives: Moving Toward Rehabilitation?, Casey Cavanaugh

Doctoral Dissertations

As prison populations climb, it is inevitable that the vast majority of incarcerated individuals will eventually return to the community. As they return, they face numerous barriers resulting from their incarceration. While it is important to identify barriers to reentry, it is also important to identify facilitators of reentry, which include forces that may mitigate reentry challenges. A tool is needed to measure this comprehensive list of barriers and facilitators, and in doing so, one may identify improvements and successes that stretch beyond merely that of recidivism. “Successful” reentry is typically measured through low recidivism rates, which recent government reports …

"She Wrote Too Much": Overproduction And The Canonicity Of Victorian Women Novelists, Elizabeth Drummey

Doctoral Dissertations

Though the Victorian era is often viewed as “the age of female novelists,” many of the most prolific and popular women writers of the time have been belittled, ignored, and forgotten. While the feminist literary recovery work of the 1980s and 1990s has brought many of these women back into scholarly consciousness, they have still not gained the respect given to their more famous yet less prolific contemporaries: the Brontë sisters, George Eliot, and Elizabeth Gaskell. In this dissertation, I argue that the reason can be found in a criticism frequently applied to these women writers both in their own …

Investigations Into Prior Knowledge And Self-Efficacy As Predictors Of Exam Performance In General Chemistry, And Student Interactions With Chemistry Textbooks, Gordon Hunter

Doctoral Dissertations

The first chapter addresses the validity and reliability of the Motivated Strategies for Learning Questionnaire (MSLQ) as a tool for chemistry education research. The study shows that the original MSLQ did not meet modern standards of reliability and presents a modified version that better captures self-efficacy in chemistry-specific contexts. The revised instrument shows improved model fit, reinforcing the importance of refining assessment tools for chemistry education research.The effects of prior knowledge and self-efficacy on student performance in a first-semester general chemistry course are investigated in the second chapter. Self-efficacy, defined as a learner's belief in their capability to successfully accomplish …

Planning Responses To Drinking Water System Emergencies, Jingyan Huang

Doctoral Dissertations

Despite extensive efforts to ensure clean and safe drinking water, drinking water contamination emergencies remain a persistent challenge in the United States. These events can result in widespread public health impacts, economic losses, and long-term environmental damage, particularly when triggered by hazardous chemical releases. Effective management of such crises requires a dual focus on both technical preparedness and human decision-making. This dissertation addresses these challenges through a two-part investigation that bridges pre-incident planning and post-incident response. It is guided by two core research objectives: (1) to evaluate commonly applied emergency countermeasures from both resilience and sustainability perspectives; and (2) to …

Psychological Factors Of Acting Talent And Success: You've Got "It", Lorelei Tierney Himlin

Doctoral Dissertations

The goal of an actor is to become invisible, bringing a character to life so convincingly that the audience forgets the actor exists outside the role. Different schools of acting often describe differing methods of portraying characters to this same general effect. To followers of the Meisner school, for example, “acting is behaving truthfully under imaginary circumstances” (Meisner et al., 1987). The “truthful” part involves creating a comprehensive mental model of a character’s imagined personality in order to fully embody that personality and extrapolate it to a situation. Then the actor uses a variety of acting techniques to think and …

Black Hole-Neutron Star Mergers: Numerical Relativity Studies Of Remnant Matter, Gravitational Waveforms, And Automated Simulation Workflows, Tia Kathleen Martineau

Doctoral Dissertations

Black hole–neutron star (BHNS) mergers are key sources for multimessenger astrophysics, offering insight into strong-field gravity and the behavior of matter at supranuclear densities. This dissertation presents three independent contributions to the study of BHNS systems using the Spectral Einstein Code (SpEC). First, a set of simulations spanning a range of mass ratios, black hole spins, and neutron star equations of state is used to map disruption thresholds and quantify remnant disk masses, unbound ejecta, and ejecta composition. These results are compared to predictions from remnant mass model FNH18, to assess its reliability in accurately predicting the resulting remnant masses …

Multi-Level Characterization And Testing Of Fatigue, Fracture And Creep Of The Ultra-High Strength Low-Alloy Steel Fabricated Via Laser Powder Bed Fusion, Nemanja Kljestan

Doctoral Dissertations

This dissertation presents a comprehensive experimental investigation of the mechanical behavior of an high-strength low-alloy (HSLA) steel fabricated via laser powder bed fusion (LPBF). The work focuses on fatigue strength, laser shock peening (LSP) effects, creep behavior, fatigue crack growth and fracture toughness. Fatigue strength was assessed using rotating bending tests, showing superior performance of LPBF specimens compared to as-cast materials due to the dual-variant martensitic microstructures. Laser shock peening enhanced fatigue life by inducing compressive residual stresses, delaying crack initiation and slowing crack propagation. Creep behavior was evaluated for different layer thicknesses, with thinner layers improving secondary creep resistance …

Simulations Of Perpendicular Electron Holes, James Patrick Mcclung

Doctoral Dissertations

Bernstein–Greene–Kruskal modes commonly manifest as electron holes and electrostatic solitary waves in space plasmas. These Debye-scale structures are nonlinear solutions to the steady-state Vlasov–Poisson system. Solutions in one dimension are highly tractable mathematically, observationally, and computationally, and are relatively well-understood. Higher-dimensional, magnetized plasmas are less amenable to study, however. Following a 20-year history of theoretical developments in two-dimensional BGK modes, this thesis presents the first high-resolution 2D and 3D simulations thereof. Stability conditions and phase-space dynamics are discovered and discussed. The simulated modes are ultimately compared to observed electron holes and modern width-amplitude relations. In addition, a significant portion of …

Missing Child Incidents Resulting In Death: Distinguishing Features Between False Allegations, Wander-Offs, And True Child Abductions, Madison N. Sundberg-Alley

Doctoral Dissertations

Children are reported missing in the United States for a multitude of reasons every year. Often, law enforcement is tasked with investigating these disappearances and recovering the missing child. In some instances, determining the reason why a child is missing can be challenging. This study focuses on three types of missing child episodes that result in fatality: child abduction homicides (CAH), false allegations of child disappearance (FACD), and wander-offs (WO). This exploratory analysis contributes to a gap in the literature by identifying some possible differences between case types that may assist police in determining the likely explanation for the disappearance. …

Analyzing Regions For The Study Of Localized Fluctuations In The Ground Magnetic Field For The Development Of A Global Risk-Assessment Forecast, Michael Kavanagh Coughlan

Doctoral Dissertations

The dynamic relationship between the solar wind and the Earth's magnetic field can produce rapid changes in the geomagnetic field measured on the ground ($dB_H/dt$). The fluctuations can be highly localized, with differences of up to 100s of nT/min in a small geographic area. The field of space weather is entering a more data-driven era, with enormous amounts of publicly available datasets from satellites and ground measurements. In this work modern machine learning techniques were employed to make forecasting risk-assessment predictions of large and localized $dB_H/dt$, and model explainability methods were employed to understand the non-linear connections being made. These …

Computational String Theory Using Machine Learning, Giorgi Butbaia

Doctoral Dissertations

Low-energy couplings of certain superstring theories are related to the masses of the particles. One of the most promising superstring theories is $\mathcal{N}=1$ supersymmetric $E_8\times E_8$ heterotic string theory. In a certain embedding of the standard model into $E_8\times E_8$ gauge group of the heterotic string, the particle spectrum consists of $(\mathbf{27})^3$, $(\overline{\mathbf{27}})^3$, $(\mathbf{1})^3$ and $\mathbf{1}\cdot \mathbf{27}\cdot\overline{\mathbf{27}}$ couplings. While the $(\overline{\mathbf{27}})^3$ couplings are quasi-topological, the $(\mathbf{27})^3$ explicitly depend on the Ricci-flat metric on Calabi-Yau.

In this dissertation, we explore recently developed techniques for calculating the normalized Yukawa couplings on various Calabi-Yau manifolds. In Chapter 2, we describe a novel architecture, …

Counting Kelp: Development And Assessment Of Modelling Approaches To Improve Understanding Of Kelp Bed Abundance And Resilience In The Gulf Of Maine, Constance N. Tyler

Doctoral Dissertations

Kelp habitats in the Gulf of Maine are threatened by rising ocean temperatures and marine invasions. The replacement of kelps with red turf macroalgae fundamentally alters these habitats and disrupts the ecosystem services they provide. Thorough assessment and monitoring of kelp habitats is needed for proper conservation of these habitats, but most long-term monitoring is performed using traditional survey methods that are restricted in the amount of space they can cover. Habitat modelling approaches are required to expand our knowledge of Gulf of Maine kelp habitats, and to better understand the interactions between kelp and red turf habitats across the …

Verifying Interchange Reconnection Models For Magnetic Switchbacks Using The Parker Solar Probe And Mms, Emily Owen Mcdougall

Doctoral Dissertations

Ever since their initial observation by the Ulysses probe, many models of magnetic switchbacks were put forth, but relatively little empirical evidence exists to verify these models, especially in terms of the ions that make up the accompanying plasma. I take energetic particle data from the Parker Solar Probe within switchbacks to provide experimental evidence to bolster the interchange reconnection driven models with particular interest in the interchange reconnection driven linear model. Statistical Analysis of switchbacks in the vicinity of CMEs, solar flares, and high-speed streams show properties consistent with the linear interchange reconnection model, and an analysis of switchbacks …

The Assessment Of Language, The Language Of Assessment: Understanding How Language Teachers Support Dynamic, Communicative Language Learning Through Assessment, Rebecca Kelley

Doctoral Dissertations

As language classrooms in K-12 schools in the United States seek to promote students’ proficiency in the language they teach and to prepare students for a multilingual world, the role of assessment in these classrooms is often overlooked. This study draws from theories of formative and dynamic assessment, as well as a socially-constructed view of language and language learning, in order to examine the way in which secondary language teachers plan for, elicit, interpret, and use evidence from classroom assessments in such a way that promotes and supports the language learning happening in the classroom. Through a series of three …

Bio-Acoustical Statistical Signal Processing For Detection, Classification, And Population Estimation In Wildlife Monitoring, Yue Liang

Doctoral Dissertations

Sound is a primary way for many animal species to communicate, forage, navigate, and assess their environment. As a result, passive acoustic monitoring (PAM), the recording and analysis of animal vocalizations, has become a valuable, non-invasive alternative to visual surveys. However, the massive volume of acoustic data generated annually, often reaching hundreds of terabytes, presents a significant challenge for efficient analysis. Since manual inspection of every frame in such data is infeasible, it is essential to develop automated detection and classification tools.

This thesis investigates and develops several statistical signal processing and machine learning techniques to address this challenge. The …

Fine Structure Of Magnetic Reconnection: Impact On Reconnection And Dissipation Rates, Steven Ver Bryck Heuer

Doctoral Dissertations

Magnetic reconnection is a fundamental process in magnetized plasmas where stored magnetic energy is converted to heat and kinetic energy. The objective of this thesis is to examine the role of small-scale structure of the reconnection region and the background plasma conditions on the rate that reconnection converts and dissipates magnetic energy. This is done using in situ data from NASA’s Magnetospheric Multiscale (MMS) mission and particle-in-cell (PIC) simulations of reconnection for different regimes. First, we introduce a new technique for measuring the reconnection rate and demonstrate its accuracy for the simplest regime of reconnection. Next, we show that it …

Resolving The Role Of Wave-Induced Pressure Gradients On The Movement Of Sediments In Nearshore Environments, Melissa Marry

Doctoral Dissertations

Characterizing the hydrodynamic forces responsible for the initiation of sediment motion is fundamental for improved understanding of large-scale sediment transport processes in nearshore environments. Traditional sediment transport models assume incipient sediment motion is only driven by the force applied by bed stress (Bagnold, 1966; Shields, 1936) while more recent work has shown that incipient motion is influenced by the forcing of the horizontal pressure gradient due to surface gravity waves (Foster et al., 2006; Frank et al., 2015; Sleath, 1999). Wave-induced vertical pressure gradients can also destabilize the sediment bed through the process of momentary liquefaction (Florence et al., 2022b; …

Essays On International Trade, Aochen Xiao

Doctoral Dissertations

This dissertation has two chapters.In Chapter 1, I develop a model of international trade with innovation and trade surplus to examine the effects of China’s large trade surplus on productivity. I abstract from future benefits from holding a present trade surplus and focus on the present gains in productivity. I find that the average productivity increase caused by trade surplus ranges from 1.2 percentage points to 5.46 percentage points when the innovation cost changes. These results explain China’s long-term export promotion policies and align with its new policy goal of developing “new productivity forces”. I also identify a negative effect …

Technologies To Support Remote Work For Collaborative Groups, Alberta Ansah

Doctoral Dissertations

The nature of work continues to evolve, particularly in the aftermath of the COVID-19 pandemic. While a substantial number of employees have returned to traditional, in-person work environments, many continue to engage in remote or hybrid work arrangements. Online meetings are a significant aspect of remote work, and while there has been a significant increase in this area, there are still aspects of these meetings that are not fully understood. Existing research in this area has primarily focused on the development of tools to facilitate meeting execution and content management. In contrast, relatively few studies have explored the social dynamics …