Purpose: The purpose of this dissertation is to quantitatively characterize and predict lung tissue motion with the goal of improving the local control of lung cancer. This is accomplished by producing a biomechanical model of lung tissue motion during quiet respiration. This dissertation proposes the development of algorithms and protocols for the analysis of motion information in 4DCT images.

Methods: A cohort of 50 patients was acquired with a 16-slice CT scanner. This data was used throughout the dissertation. Based on the law of volume conservation, a relationship between the tidal volume and the geometric expansion of the torso was devised and used to improve breathing motion studies. The breathing patterns of these patients were used to characterize breathing patterns based on the measured external surrogate information with the aim of improving the efficiency of linear accelerator gating windows. A characteristic breath was defined as an average breath for use in generating patterns representative of realistic motion for breathing motion studies. A prospective gating algorithm was developed to allow the acquisition of user specified breathing phases with a relatively simple model to accurately predict respiratory phase occurrence in order to reduce the number of scans necessary to obtain sufficient data for breathing motion modeling. A new term to the breathing motion model to account for cardiac induced lung tissue motion was developed to improve the accuracy of the model.

Results: Breathing studies can be optimized by placing the surrogate device between the third and fourth lumbar vertebra. Three types of breathing patterns were observed in the patient cohort. The hysteresis component of lung tissue trajectories was shown to be between 8 - 18 % of the volume filling component of motion. A simple prediction algorithm was shown to be a significant improvement over commercially available software. An additional term was devised to account for cardiac-induced lung motion and was shown to be accurate.

Conclusion: This dissertation has demonstrated new quantitative methods to characterize lung tissue motion. Future work includes incorporating the work described in this dissertation into a new fast helical CT image acquisition protocol for breathing motion modeling.

Chapter 1. Previous collaborative work between the Arnold and Bergman groups on niobium and tantalum systems supported by N,N’-diaryl-β-diketiminate (BDI, aryl = 2,6-iPr2-C6H3) and tert-butylimido ligands is summarized. Routes to prepare high-valent niobium and tantalum halide and alkyl starting materials are described, and the reactions of these complexes with small molecule substrates are discussed. Reactions to access low-valent niobium systems are described, and several examples are provided in which low-valent niobium systems promote unusual stoichiometric and catalytic transformations. In addition, the chemistry of high-valent BDI niobium bis(imido) systems is discussed.

Chapter 2. The nitrene transfer reactivity of a series of BDI niobium bis(imido) complexes is reported. A novel metathesis process results in nitrene fragment exchange between alkylimido groups in Nb(V) bis(imido) complexes and arylisocyanide substrates. Calculations and experimental evidence indicate that these reactions likely proceed through cycloaddition and cycloreversion steps involving Nb(V) η2-carbodiimide intermediates, and occurs at a single metal center without elimination of carbodiimide. In contrast, reaction with unhindered alkylisocyanides results in extrusion of dialkylcarbodiimide, a process that was rendered catalytic in the presence of excess azide. This represents a rare example of oxidative nitrene transfer promoted by an early transition metal complex, in which reactivity across an imido group and two-electron metal-based redox chemistry are used in tandem to effect catalytic turnover.

Chapter 3. BDI niobium bis(imido) complexes are shown to react with a variety of substrates across their Nb-N π-bonds by cycloaddition and 1,2-addition. Niobium bis(imido) intermediates generated by treatment of a Nb(III) precursor with azide substrates react further with azide substrates via [3+2] cycloaddition to give niobium tetrazene complexes. These compounds exist in equilibrium with the corresponding bis(imido) complexes, and are competent catalyst precursors for oxidative nitrene transfer to generate carbodiimides. Isolated bis(imido) complexes are also shown to engage in stoichiometric 1,2-addition reactions with dihydrogen, silanes, boranes, thiols, and terminal alkynes. These bis(imido) compounds also exhibit [2+2] cycloaddition and cycloreversion reactivity with carbon dioxide and carbon disulfide. Through these studies, the first example of an isolated early transition metal (group 3 to 5) complex bearing both a terminal imido and a terminal oxo ligand is accessed. Likely as a consequence of π-loading effects, this compound is reactive toward 1,2-addition of silane substrates across its oxo group.

Chapter 4. The cyclometallated tantalum(V) hydride complex {ArNC(Me)CHC(Me)N[2-(CHMeCH2)-6-iPr-C6H3]}Ta(NtBu)H was prepared from hydrogenolysis of (BDI)TaNtBuMe2 (BDI = N,N′-diaryl-β-diketiminate, aryl = 2,6-iPr2-C6H3). Based on mechanistic studies, formation of the hydride complex likely proceeds through a dihydride intermediate generated from successive σ-bond metathesis steps. Low-valent Ta(III) dicarbonyl derivatives are accessed by either introducing CO atmosphere to the DMAP adduct at room temperature, or by directly adding CO at low temperature. Instead of promoting reductive elimination, 2,6-dimethylphenylisocyanide reacts with the tantalum hydride complex via migratory insertion to give a product containing a unique metallaimidazole ring. This complex can be reversibly oxidized by one electron either electrochemically or chemically to give a tantalum radical cation species. DFT calculations, as well as X-ray crystallographic and EPR spectroscopic data are consistent with the electron being removed from an orbital primarily composed of Ta-C π-bonding character, but also delocalized over the tantalaimidazole ring.

Chapter 5. The synthesis and reactivity of niobium and tantalum complexes bearing tert-butylimido and N,N′-di-2,4,6-trimethylphenyl-β-diketiminate (BDIAr) or N,N′-di2,6-dichlorophenyl-β-diketiminate (BDICl) ligands is reported. Reaction of dimethyl complex (BDIAr)Nb(NtBu)Me2 with dihydrogen leads to generation of bis-μ-hydrido Nb(IV)-Nb(IV) complex {(BDIAr)Nb(NtBu)(μ-H)}2. One-electron oxidation of this complex results in release of dihydrogen to generate the imido-bridged mixed-valent Nb(III)-Nb(IV) dimer [{(BDIAr)Nb(μ-NtBu)}2][B(C6F5)4]. EPR spectroscopic measurements and DFT calculations are consistent with a symmetric structure containing a Nb-Nb single bond in which the unpaired electron is delocalized over both niobium centers.

Clock distribution networks consume a significant portion of total chip power

in high-performance designs. Of many proposed solutions to this drain, clock resonance

has been shown to be an effective method for dealing with chip power and area issues

with savings of 20% in modern designs as well as a lower number of required clock

buffers. Current resonant solutions come with the limitation of optimal performance

at one particular frequency which may be unsuited for the task at hand. For instance,

switching from number crunching at work to a kitchen timer at home. If careful tuning

is not made then excess power may be spent instead of saved. This thesis introduces the

first scheme to produce a clock distribution network with a tunable resonant frequency.

Experimental results show the resonant frequency ranges from 1.2GHz to 2.6GHz. This

is done while saving up to 41% power on the clock distribution network when compared

to the non-resonant distribution.

The energy industry is undergoing a rapid transformation in the United States. Climate change is leading to many of the changes, including market policy development, and the transition away from old technologies to new. The changes are leading to new challenges, real or perceived. These speed of these changes is resulting in the need for policy makers and electricity system planners to make decisions under uncertainty and modify their behavior as they learn from their policies and actions. In this dissertation I strive to understand how climate policies effect regions without climate policies, and the impacts of changing energy technologies on society. The first chapter of this dissertation takes up the effect of regional climate policies, and the second two take up the energy transition.

In the fist chapter of this dissertation,I conduct the first reduced form accounting analysis of leakage in the California electricity sector following the enactment of the Cap-and-Trade program. Leakage is the result of incomplete regulation, where in this context the Cap-and-Trade program only regulates a subset of the electricity market, leading to the unintended increase in carbon dioxide emissions through the substitution of generation from the regulated region to the unregulated region. The paper finds near-term emissions are below that of unaccounted for emissions, but utilization of coal is greater than accounted for by regulators. I then find across the enactment date of the Cap-and-Trade program emissions from unregulated entities increased by 26 percent as opposed to falling by 32 percent as reported. This implicates the need to find stronger methods to reduce imported emissions from unregulated entities.

In the third chapter of this dissertation,in collaboration with James Bushnell and David Rapson, we study the coal industry and labor. Coal plays an important role in the social zeitgeist to ensure communities maintain a quality labor force. We conduct a study on the impact of coal power plant retirements on local employment from 2010-2018, and find on average there is no impact to employment within the labor market. We implement an event study and synthetic control approach to estimate the dynamic effect of the retirement and find the accusations that the loss of a coal facility are largely attributable to secular trends. We further study the effect of labor market thickness on the impact of the retirements to find there is no statistical relationship with the labor market size. We find there is heterogeneity in the effect of a retirement, but there are no predictive variables to allow us to discern why there may be a large positive or negative effect. The findings are robust to multiple empirical approaches and specifications.

In the third chapter of this dissertation, also in collaboration with James Bushnell and David Rapson, we take advantage of energy technology deployment across California to study the relationship between emerging energy technologies. Specifically electric cars and residential solar, and their impacts on the reliability of the distribution grid. The results reveal that there is no impact associated with the deployment of new technologies on the grid. The findings suggest that grid planners are able to make the necessary investments to avoid adverse impacts from emerging technologies on grid reliability, and deployment should not be slowed. Our results find that there are minimal effects immediate impacts following deployment of these distributed technologies, but there is no relationship with the long-term impact from these technologies.

Conventional sampling systems (nets, pumps, acoustics, and most optical imaging systems) are inadequate to study planktonic trophic interactions. However, Zooglider, a novel endurance zooplankton sensing glider, is shown here to be uniquely capable of resolving planktonic trophic interactions at 5 cm vertical resolution.

In March 2017, Zooglider’s optical (Zoocam) and acoustic backscatter (Zonar) systems were compared against conventional ship-based nets (MOCNESS) and acoustics (EK80). Zoocam observed similar abundances of robust organisms (chaetognaths, euphausiids, and nauplii) and greater abundances of both smaller and more delicate zooplankton. Compared to the MOCNESS, Zoocam observed significantly more smaller appendicularia and copepods, while simultaneously observing significantly more larger gelatinous predators (ctenophora and hydromedusae) and mineralized protists (foraminifera, phaeodaria, and mostly acantharia). Furthermore, Zoocam revealed in situ local maxima in organismal abundances that were not resolvable by the coarser net resolution. Zonar matched the relative distributions and magnitude of ship-based acoustics, without the disadvantage of reduced signal-to-noise ratios in deeper depths.

From seven deployments spanning 15 months, Zooglider revealed the limitations of solely using chlorophyll-a fluorescence (Chl-a) as a proxy for herbivorous zooplankton prey. Zoocam observed that marine snow, small particles, and many zooplankton taxa, i.e., appendicularians, copepods, and large mineralized protists (primarily acantharia), have bilinear and nonlinear relationships with Chl-a concentrations. In most cases, zooplankton showed improved overlap with distributions of small suspended particles than with Chl-a. Furthermore, marine snow and small particles were determined to be the primary explanatory variables for zooplankton abundances, whereas Chl-a was either secondary or insignificant. No relationship was found between maximum water column stability and zooplankton or prey abundances.

Zooglider also detected size-dependent zooplankton predator-prey interactions. Size-dependent vertical distributions were found for three prey taxa and five predatory taxa and differential size-dependent diel vertical migration behavior was detected for copepods and chaetognaths. Zoocam images showed in situ predator-prey encounters (co-occurrence of predator and prey within a 250 mL sample volume). Analysis of these encounters revealed that abundances of smaller predatory zooplankton (chaetognaths, ctenophores, siphonophores, and trachymedusae) have stronger relationships with abundances of smaller prey and that smaller predators have greater observed probabilities of encountering smaller prey.

This dissertation traces transatlantic processes of German religious and social identity formation in eighteenth-century North America through the lens of an expansive correspondence network established by the pastoral missionaries and common believers of the Moravian Church, a small group of radical German Protestants who migrated to all four Atlantic world continents and built community outposts and mission settlements in diverse religious, political, and social environments. Common Moravian believers, I argue, fashioned this pioneering correspondence network into a critical element of their lived religious experience and practice, and it became fundamental to both the construction and maturation of their personal and collective identities. In addition, this correspondence network functioned as a medium for ordinary believers to articulate nonconformist spiritualities, communicate new standards of moral conduct, and advocate alternative gender and racial hierarchies. British American society worked to construct and then deconstruct Moravian radicalism in the public sphere by attacking and then respecting the embodied piety, religious practices, and spiritual authority of common Moravian believers.