Three routes to more efficient photovoltaics using conformal Cu2S, organic luminescent films, and nanocrystalline PbSe films are outlined below. Properties of these materials are investigated experimentally and numerically in separate studies.

In the first study, chemical vapor deposition (CVD) processes were used to fabricate Cu2S using hydrogen sulfide and the metal-organic precursor, KI5. The alternating exposure of mesoporous TiO2 and planar ZnO to the two precursors resulted in films that penetrated porous structures and deposited at a constant rate of 0.08nm/cycle over the temperature range 150C-400C. Sheet resistance and optical absorption measurements suggest the presence of a metallic copper-poor phase of less than 100nm thick forming at the Cu2S/substrate boundary.

In a separate study, organic films doped with luminescent dyes were placed above CdTe/CdS solar cells to convert high energy photons to lower energies, better matched to the CdTe/CdS quantum efficiency peak. Efficiency improvements of up to 8.5% were obtained after optimizing dye concentration, dye chemistry, and the host material. Long-term stability tests show that the organic films are stable for at least 5000 hours under 1 sun illumination provided that the dye is encapsulated in an oxygen and water free environment.

Finally, a Monte Carlo model was developed to simulate electron and hole transport in nanocrystalline PbSe films. Transport is carried out as a series of thermally activated tunneling events between neighboring sites on a cubic lattice. Each site, representing an individual nanocrystal, is assigned a size-dependent electronic structure, and the effects of crystal size, charging, inter-crystal coupling, and energetic disorder on electron and hole mobilities/conductivities are investigated. Results of simulated field effect measurements confirm that electron mobilities and conductivities increase by an order of magnitude when the average nanocrystal diameter is increased in the 3-5nm range. Electron mobilities/conductivities begin to decrease for average nanocrystal diameters above 6nm. Our model suggests that as crystal size increases, fewer hops are required to traverse a given film length and that site energy disorder significantly inhibits transport in films composed of smaller nanocrystals. The dip in transport above 6nm can be explained by a decrease in tunneling amplitudes and by carrier interactions, which become more frequent at larger crystal diameters. Using a nearly identical set of parameter values as the electron simulations, hole simulations confirm experimental mobilities, which increase with nanocrystal size over two orders of magnitude.

One of the most important cellular decisions made by the immune system is whether or not a T cell will activate after contacting and antigen presenting cell (APC). This choice occurs and is regulated at the site of contact between a T cell and an APC. A hallmark of this “immunological synapse” is the partitioning of membrane proteins to create biochemically distinct domains that initiate signaling. Though the importance of protein segregation at the immunological synapse has been appreciated for decades, the mechanism by which proteins partition into different domains and how partitioning is modulated for regulation were not well understood. In this study, I aimed to understand how receptor and co-receptor organization on the T cell membrane controls signaling.

Companies that can leverage their product descriptions to find meaningful insights have a competitive advantage in reaching and understanding their consumer. In practice, however, this is a challenging task. Product descriptions may be written by a number of different individuals with inconsistent formatting. They may contain typos, inaccurate representations and complex terminology so unique to a single product as to be meaningless to analyze alongside other products.

For this reason, the study of Product Attribute Extraction (PAE) aims to extract meaningful at- tributes from product descriptions with the goal of producing a structured dataset of attribute-value pairs. Prior work has focused largely on conventional natural language processing (NLP) techniques to identify such relationships. In this paper, we combine the architecture of transformers and variational autoencoders (VAE) to merge and format semantically similar product descriptions with the goal of decreasing the complexity of PAE. We demonstrate examples of the feasibility of this approach and assess its potential, shortcomings and application to the field.

This dissertation is an ethnography of the inaugural artist-in-residence program (2013-2015) at the Portland Archives & Records Center (PARC) in Portland, Oregon. Despite over the past two decades of abundant artistic engagement with archives, a concurrent increase in artist-in-residence projects within institutional archives, and a rich humanities-centered discourse about artists’ archival endeavors, significant attention has yet to be given by the field of archival and recordkeeping studies to the ways in which artists respond to records; to the kinds of conceptual, aesthetic, and physical work artists do with records; and, to the kinds of social and cultural relations into which archives enter through art practice, production, circulation, and reception. Moreover, the field lacks information about how people respond to records, what records can inspire people to do, what kinds of things can be done with records, and what kinds

of interactions occur and relationships form around the use of records and archives. This project addresses these concerns and explores through data collected from participant observation, in-depth interviews, and document analysis the implementation and management of the residency program and the ways in which poet Kaia Sand and interdisciplinary artist Garrick Imatani engaged and transformed Portland Police Bureau surveillance records into art and literary works in collaboration with activists whose livelihoods are caught in the records and other Portland community members. Further, through engaging object biography and the records continuum, this project considers the affects and effects of the surveillance records over time and space. Key findings indicate that artists’ archival art practices and works open-up archives to different forms of meaning-making processes and productions (e.g., experiential, social, aesthetic), and situate archives as potent stimuli, conduits, and spaces for social, cultural, and political productions that encourage dynamic cross-disciplinary and community interactions where new understandings about the past and present and possibilities for the future can emerge. Findings also reveal that besides being vital tools for evidencing human activity and transmitting memory, records, through the forces of their materiality and the presence of human bodies and activities they invoke, are affectively charged objects able to move people into new ways of being and doing, relations and alignments that can effect changes in personal and social circumstances and foster relationships between people in unpredictable, generative, and community building ways.

Evidence of racial disparities across a number of important domains, combined with documentation of persisting prejudice and stereotypes disfavoring racial minorities, suggests that decision processes are not immune from the influence of racial bias. The operation of such bias threatens public values of fairness and equality, particularly in contexts where matters of life and liberty are at stake, such as the criminal justice system. Accountability--the requirement of having to justify oneself through the giving of reasons--is a procedural device commonly used by organizations of all kinds (e.g., police departments, prosecutor offices, courts) to improve the quality of decisions.

While scholars and organizations turn to accountability as a strategy to reduce racial bias, the existing evidence justifying this reliance is tenuous at best. As my review of the literature shows, whereas previous research suggests accountability can effectively address a range of cognitive biases under the right conditions, studies focusing on the effects of accountability on intergroup biases have produced mixed results. In some cases, accountability can operate to actually bolster intergroup biases. Further, no known study has directly examined the effect of accountability on implicit (unconscious) racial bias. To avoid the adoption of ineffective or potentially harmful practices, further research is needed on accountability's ability to reduce the influence of racial bias in the decision process.

The current project presents results from three experimental studies testing accountability's capacity to attenuate the effects of explicit and implicit racial bias. Using a case file paradigm, online participants reviewed either a White or racial minority criminal suspect and rendered judgments about the seriousness of the crime, suspect guilt, and the appropriate punishment. Study 1 compared the relative effects of holding decision-makers accountable either for the decision outcome itself (outcome accountability) or for the process used to reach the decision (process accountability). In this study, college students reviewed either a White or Black suspect in a drug possession case. Only limited evidence was found for accountability's ability to address racial bias, with the process accountability manipulation faring marginally better than outcome accountability.

Focusing on different aspects of the justification process, Study 2 examined the effects of having decision-makers respond to a general prompt to provide reasons for their judgments (undirected accountability) versus responding to a series of targeted questions designed to focus attention on the criteria used and the weighing of factors within the decision process (directed accountability). This latter form of accountability more closely simulates filling out a standardized form, which many organizations use when evaluating cases in a variety of contexts, such as hiring. In this study, a national sample of adults recruited from Amazon Mechanical Turk reviewed either a White or Black suspect across three different criminal files: drug possession, vandalism, and robbery. Contrary to expectations, those in the control condition did not show the baseline pattern of racial bias. While control participants tended to give harsher outcomes to the White suspect, this same pattern was not found in the two accountability conditions. Limited evidence of racial bias was found in each of the accountability conditions, at least for one of the case files.

Study 3 also examined undirected versus directed accountability, with MTurk workers reviewing either a White or Hispanic suspect across two case files: vandalism and battery. In addition to the measures of explicit racial bias included in the first two studies, measures of participants' implicit racial bias were also examined. While racial disparities in outcomes did not emerge for any of the conditions, the control and two accountability conditions all showed some evidence that suspect race was related to their decisions, at least some of the time.

Keeping in mind the limitations stemming from the experiment-based nature of the project, the collective findings from these studies caution against conclusions that accountability effectively addresses the influence of racial bias in the decision-making process.