Digital Commons Network^™

Carbon Emissions From Streams And Rivers: Integrating Methane Emission Pathways And Storm Carbon Dioxide Emissions Into Stream And River Carbon Balances, Andrew Robison

Doctoral Dissertations

River networks play an important role in elemental cycling at watershed, regional, and global scales. They not only serve as pipes that transport elements from land to sea, but also as complex processers that can significantly modify the timing, form, and magnitude of these elemental fluxes. For example, recent studies have shown that river networks contribute significantly to the global carbon cycle by emitting greenhouse gases like carbon dioxide (CO¬2) and methane (CH4) to the atmosphere. However, we currently do not fully understand the controls on GHG emissions from river networks, particularly what drives the variability of emissions across space …

Utilization Of Exotic Germplasm In A Cucurbita Breeding Program, Andrew Burkeland Ogden

Doctoral Dissertations

Crops in the Cucurbitaceae plant family are an important part of agricultural systems worldwide. This family includes economically important crops such as watermelon, cucumber, pumpkins, melons, and squash. These crops are plagued by a wide variety of both insect and plant pathogen pests. Breeding for genetic resistance to these pests represents a key component of many cucurbit breeding programs in both public and private sectors. Sources for disease and pest resistance often include wild species and landraces found across the world. Often, such species show poor adaptability to temperate climates. This limits plant breeders’ abilities to utilize exotic germplasm and …

Experimental Characterization And Crystal Plasticity Modeling Of Mechanical Properties And Microstructure Evolution Of Additively Manufactured Inconel 718 Superalloy, Saeede Ghorbanpour

Doctoral Dissertations

In this thesis, the mechanical behavior of the additively manufactured (AM) IN718 nickel-based superalloy and their correlations with the evolution of microstructure are studied comprehensively. The effects of manufacturing parameters, build orientations, and post processing procedures, i.e. standard heat treatment and hot isostatic pressing (HIP), on various mechanical properties including monotonic compression and tension strength, low cyclic fatigue performance, high cyclic fatigue behaviour, and fatigue crack growth behavior are investigated. Due to the high temperature applications of the IN718 alloy, elevated temperature properties are examined as well. Electron Backscattered Diffraction (EBSD) technique is employed to measure the initial and deformed …

A High-Performance Full-Field Crystal Plasticity Solver Within Finite Elements For Micromechanical Simulation Of Metallic Components Under Large Deformations, Adnan Eghtesad

Doctoral Dissertations

It is undeniable that metals and metallic alloys are of great significance in automotive and aerospace industry. Metallic materials are aggregates of grains (i.e., crystals) in orders of microns. Understanding the behavior of multi-phase metallic structures plays a vital role in automotive and aerospace design and manufacturing industries. Work presented in this dissertation presents a high-performance crystal plasticity solver, capable of performing simulations of massively large data sets in order of few hours instead of months of run. The developed accelerated solver is capable of performing simulations of massively large data sets representing very high-resolution microstructures with tens of millions …

Metareasoning For Heuristic Search Using Uncertainty, Tianyi Gu

Doctoral Dissertations

Heuristic search methods are widely used in many real-world autonomous systems. Yet, people always want to solve search problems that are larger than time allows. To address these challenging problems, even suboptimally, a planning agent should be smart enough to intelligently allocate its computational resources, to think carefully about where in the state space it should spend time searching. For finding optimal solutions, we must examine every node that is not provably too expensive. In contrast, to find suboptimal solutions when under time pressure, we need to be very selective about which nodes to examine. In this dissertation, we will …

Synthesis Of Thioacids And Dicarboxylic Acids Derived From Open Β-Lactams For Inhibition Of Metallo-Β-Lactamases, Junfu Chen

Doctoral Dissertations

Antibiotics are important substances that have been used in clinical treatment for over 70 years. Because of overuse and misuse of antibiotics, bacteria developed resistance. However, bacterial resistance towards antibiotics, especially the β-lactam antibiotics, is becoming increasingly threat. Currently, the β-lactam antibiotics are seriously threatened by β-lactamases. Metallo-β-lactamases (MBLs), a sub-class of β-lactamases, have been found in several bacteria since they confer resistance to many different β-lactams, and as a result, the bacteria survive in their presence. A potential treatment is to synthesize inhibitors of MBLs, however, there are no inhibitors synthesized in clinical use. The goal of this project …

High Level Learning Using The Temporal Features Of Human Demonstrated Sequential Tasks, Madison Brandywine Clark-Turner

Doctoral Dissertations

Modelling human-led demonstrations of high-level sequential tasks is fundamental to a number of practical inference applications including vision-based policy learning and activity recognition. Demonstrations of these tasks are captured as videos with long durations and similar spatial contents. Learning from this data is challenging since inference cannot be conducted solely on spatial feature presence and must instead consider how spatial features play out across time. To be successful these temporal representations must generalize to variations in the duration of activities and be able to capture relationships between events expressed across the scale of an entire video.

Contemporary deep learning architectures …

Molecular Architecture Of Rod Photoreceptor Phosphodiesterase In Its Nonactivated And G-Protein Activated States, Michael Irwin

Doctoral Dissertations

The photoreceptor phosphodiesterase (PDE6) plays an important role in the G-protein coupled visual signaling pathway which uses cGMP as a second messenger to convert light stimuli into electrical signals. PDE6 is a tetrameric peripheral membrane protein consisting of two catalytic subunits and two inhibitory subunits and is localized to the outer segment membranes of rod and cone photoreceptors. Mutations in this enzyme are one cause of retinitis pigmentosa and other retinal degenerative diseases resulting in blindness or visual dysfunction that lack adequate therapeutic intervention due to inadequate knowledge of PDE6 structure and regulation PDE6 is tightly regulated in the nonactivated …

Biologically Inspired Computer Vision/ Applications Of Computational Models Of Primate Visual Systems In Computer Vision And Image Processing, Reza Hojjaty Saeedy

Doctoral Dissertations

Biologically Inspired Computer VisionApplications of Computational Models of Primate Visual Systems in Computer Vision and Image Processing Reza Hojjaty Saeedy Abstract Biological vision systems are remarkable at extracting and analyzing the information that is essential for vital functional needs. They perform all these tasks with both high sensitivity and strong reliability. They can efficiently and quickly solve most of the difficult computa- tional problems that are still challenging for artificial systems, such as scene segmentation, 3D/depth perception, motion recognition, etc. So it is no surprise that biological vision systems have been a source of inspiration for computer vision problems. In …

Unmanned Aerial Systems (Uas) As A Tool For Investigating Edge Influences In New Hampshire Forests, Heather Marie Grybas

Doctoral Dissertations

The continued decline in forest cover across New England becomes more concerning when faced with the fact that these same forests may be playing an important role in the fight against climate change. New Hampshire, in particular, is experiencing a 0.27% annual net loss in forest cover as of 2018. Increased population growth and accompanied development has resulted in the removal of forest cover and the fragmentation of once continuous forest blocks. Fragmentation can lead to further degradation of the remaining forest stands via alterations of the biotic and abiotic process at their edges. The use of unmanned aerial systems …

Cognitive Buffer-Aided Cooperative Networks: Scheduling, Resource Allocation, And Performance Analysis, Omid Moghimi Kandelusy

Doctoral Dissertations

Electromagnetic spectrum, as a limited resource, is prone to scarcity due to the astronomical growth in demands for ubiquitous wireless connectivity in the past few decades. Meeting such an ever-growing demand is contingent upon optimizing the spectrum utilization. In this context, dynamic spectrum access policies, such as spectrum sharing, are promising solutions to mitigate the spectrum gridlock. Spectrum sharing networks are allowed to operate on the licensed frequency bands as the secondary users of the spectrum provided that the licensed primary network is protected from any disruptive interference due to the coexistence. The stringent constraints on the secondary network for …

Multiscale Dynamics Of Energy Transfer Within The Electron Diffusion Region Of Magnetic Reconnection, Dominic Payne

Doctoral Dissertations

During the process of magnetic reconnection, anti-parallel magnetic fields with embedded plasma particles converge and undergo a dramatic topological reconfiguration in the electron diffusion region (EDR) while releasing some of the stored magnetic energy directly into the particles. This process is ubiquitous in natural plasmas, and is responsible for many of the explosive phenomena observed in the Earth's magnetosphere and on the sun. While it has long been established that magnetic reconnection is a plasma energization process, it is still unclear what mechanisms underlie the energy conversion from fields to particles, particularly in the EDR where magnetohydrodynamic (MHD) approximations are …

The Application Of Iron-Based Materials In Aqueous Energy Storage, Fenghua Guo

Doctoral Dissertations

Aqueous energy storage has been an important part of battery research for its cost-effective, environmentally benign, and robust nature. Iron-based materials, including iron hydroxides and iron oxides, are widely investigated as electrode materials for their extremely low cost and sufficient discharge capacity. Iron-based electrode materials were often operated in strong alkaline electrolytes, experiencing either slow reaction kinetics, severe side reactions, or significant capacity loss over cycling. This research focused on the application of iron-based materials in aqueous electrolytes with low alkalinity. This research showed that the synthesized γ-FeOOH measured with a cocktail electrolyte of sodium sulfate and sodium hydroxide demonstrated …

I. Incorporation Of Functionality At The Β-Position For The Zinc-Mediated Chain Extension Reaction Ii. Formal Synthesis Of Heliotridane And Pseudoheliotridane Through A Zinc-Mediated Chain Extension Approach, Nicholas Alexander Arnista

Doctoral Dissertations

The zinc-mediated chain extension reaction has been previously developed to incorporate alkyl or aryl substituents at the β position of the chain-extended product. The incorporation of heteroatom functionality at the β position of the chain-extended product was demonstrated through the use of a functionalized zinc carbenoid species. Silyl ether-functionalized geminal diiodides were used in the chain extension reaction with low to modest yields. Optimization of the chain extension reaction was performed by modification of solvent, reaction temperature, reaction time, and addition of diiodide. The chain extension reaction was performed on several different substrates, such as β-keto esters, β-keto amides, and …

Ligand Design In C-Functionalized Cobalt Cyclams For Hybrid Photocatalytic Co2 Reduction, Ethan Edward Jarvis

Doctoral Dissertations

Global climate change is one of the most significant risks to both the planet and all life on it. The largest contributor to this ever-growing threat is CO2 and its continued emission into the atmosphere. As a result, many scientists are researching CO2 reduction processes to help slow and potentially reverse the climate change by reducing the atmospheric levels of CO2. Ideally, these reduction processes convert CO2 into useful materials such as hydrocarbon-based fuels such as methanol or ethanol, which could also help remove our dependence on finite natural energy resources. CO2 reduction is challenging to do efficiently however, due …

Preventing Violence Among Adolescents: The Many Roles Of School Personnel, Andrew Rizzo

Doctoral Dissertations

Youth violence can encompass a range of types of harmful behaviors that each have their own definitions, high prevalence rates, and litany of negative consequences for both adolescent victims and perpetrators. It includes behaviors that can be labeled based on the nature of the act itself such as physical assault, verbal harassment, relational violence, sexual violence, or cyber violence (Basile et al., 2020; Hasbrouck, 2020). One of the primary avenues of youth violence prevention is through school-based programs that often involve school personnel (Butchart et al., 2019). This dissertation contributes to the extant knowledge about school personnel’s impact on preventing …

Pine River Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

No abstract provided.

Chocorua Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Chocorua Lake (Station 1 - South, Tamworth, NH) in 2021.

Baboosic Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Baboosic Lake (Amherst and Merrimack, NH) for 2021.

Balch Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Balch Pond (Wakefield, NH; Acton and Newfield, ME) for sampling efforts up to 2021.

Shaws Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Shaws Pond in New Durham, NH in 2021.

Marsh Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Marsh Pond in New Durham, NH in 2021.

Jones Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Jones Pond in New Durham, NH (Stations 3 - Deep) in 2021.

Wentworth Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Wentworth Pond in New Durham, NH in 2021.

Lake Kanasatka 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Lake Kanasatka in Moultonborough, NH in 2021.

Loon Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Loon Lake (Deep station, Effingham, NH) in 2021.

Loon Lake 2021 Water Quality Full Annual Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Report by UNH CE Lakes Lay Monitoring Program for Loon Lake in Effingham, NH.

Lake Wentworth (Station 2 - Triggs) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Lake Wentworth in Wolfeboro, NH ( Station 2 - Triggs) in 2021.

Lake Wentworth (Station 1 - Fullers) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Wentworth Lake in Wolfeboro, NH (Station 1 - Fullers) in 2021.

Lake Wentworth (Station 12 - Governors) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Wentworth Lake in Wolfeboro, NH ( Station 12 - Governors) in 2021.