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Recent advances in interactive web technologies, combined with widespread broadband and mobile device adoption, have made online collective action commonplace. Millions of individuals work together to aggregate, annotate, and share digital text, audio, images, and video. Given the prevalence and importance of online collective action systems, researchers have increasingly devoted attention to questions about how individuals interact with and participate them. I investigate these questions with the understanding that an individual's behaviors and attitudes depend in part on what they know and believe about how the online collaborative system operates --- the "nuts and bolts," so to speak.In this dissertation I examine how social operational information --- information and beliefs about the other people who act in online collective action systems --- can influence individuals' attitudes, assumptions, behaviors, and motivations with respect to those systems. I examine the role of social operational information from two distinct but related perspectives. First, I employed a social psychological laboratory study to examine the influence of a specific type of social operational information: relative competence feedback. Experimental findings demonstrate that individuals who received information that they were of low relative competence compared to others contributed less to a collective good compared to those who received either average or high relative competence feedback. Two key attitudes about abilities and responsibilities in inter-dependent situations --- self-efficacy and social responsibility --- mediated the competence--contribution relationship. Furthermore, individual participants' stable preferences about the distribution of rewards for themselves and other people (social value orientation) moderated the the observed changes in contribution rates across experimental conditions.Secondly, I conducted a qualitative interview study of Wikipedia's infrequent editors and readers. The study focused on documenting and understanding participants' attitudes, beliefs, and assumptions about Wikipedia's social system and the other individuals who contribute to it. Interviews focused on questions about the nature of Wikipedia and its' user-generated system, the characteristics of the people who write Wikipedia, and the motivations that encourage their participation. Qualitative analysis revealed a variety of tensions around the nature of Wikipedia as an open, user-generated system, as well as between widespread negative stereotypes of contributors as geeks, nerds, and hackers and equally prevalent positive assumptions about their pro-social motivations for contributing to Wikipedia. I argue that these tensions reveal a transition towards a view of online collaborative work as open, creative, and focused on collaboration, dominated by intrinsic motivations such as passion, interest, and a desire to contribute something to the world. This emerging view of work on Wikipedia is captured by Himanen's notion of The Hacker Ethic. Finally, I explore how qualitative and experimental findings can speak to each other, and discuss some methodological challenges and best practices for combining experimental and qualitative methods. I argue that triangulating qualitative and experimental results in the context of this study facilitates: (1) lending detail and nuance to our understanding of complex attitudes such as social responsibility, and (2) improving the ecological validity of experimental findings by vetting assumptions about competence and social roles / responsibilities in a real-world context.

The total chemical synthesis of 361-residue Dpo4 DNA polymerase (including N-terminal His-tag) is an ambitious undertaking that pushes the limits of solid-phase peptide synthesis (SPPS). In chemical protein synthesis projects, smaller peptide segments are synthesized using SPPS and these segments are ligated together via native chemical ligation (NCL) to produce a full-length protein. NCL is a chemoselective reaction that requires a C-terminal thioester and an N-terminal Cys residue to ligate peptide segments. These requirements pose a challenge to synthetic protein chemists because Cys residues are rare in most proteins and C-terminal thioester selection is crucial to the success of the project because some thioesters react quickly and efficiently while others are slow and produce very low yields. A strategically placed mutation, usually to optimize ligation sites, can make an impossible chemical protein synthesis project possible. However, mutations must be chosen carefully to minimize their impact on the activity of the protein. In the case of Dpo4, we identified three positions where mutations would greatly simplify our chemical synthesis efforts. In order to safely make mutations, we used BLAST searches and crystal structure analysis to determine candidate residues. We recombinantly expressed mutated Dpo4 constructs and compared their activity against wild-type Dpo4. In this manuscript, we discuss the selection of the three mutated positions and the development of a PCR assay that allowed us to quantify differences in thermostability between mutant Dpo4 constructs and wild-type Dpo4. This research highlights the importance of strategically placed mutations in chemical protein synthesis projects and also has the potential to impact the biotechnology field with the introduction of mirror-image PCR using chemically synthesized D-Dpo4 as the DNA polymerase.

Explored the relationship between children's internal or external locus of control orientation and their attitude toward school and self-concept as learners in school. Results support the premise that students with an internal locus of control will favor open-space schools; while students with an external locus of control will favor traditional schools. Speech presented at the Convention of the International Association of Pupil Personnel Workers, Charleston, South Carolina, 1975. (Author/EJT)

DNA molecules encoding two proteins, HipHop and MSK81, were cloned into bacteria so as to make large amounts of these proteins that bind to telomeres of Drosophila (fruit fly) chromosomes. The goal was to determine whether known DNA binding motifs are present in HipHop and MSK81. Understanding how these proteins interact with telomeres is relevant due to the important role telomeres play in maintaining genome stability. Drosophila telomeres differ from most other eukaryotic telomeres because the telomere DNA in fruit flies is made by retrotransposition and not by telomerase. This retrotransposition-based method of making telomere DNA is especially interesting because certain types of cancer cells employ similar methods to elongate their telomeres without the use of telomerase. We hypothesized that the proteins HipHop and MSK81 bind DNA at telomeres and tested this in a reductionist approach involving purification of the individual proteins. If HipHop and MSK81 bind telomere DNA in fruit flies, then the purified proteins should also bind to molecules that mimic fruit fly telomeres. Cloning the DNA encoding HipHop and MSK81 involved PCR amplification and insertion into a plasmid DNA molecule capable of being incorporated into bacterial cells. This plasmid DNA was placed into bacterial cells and protein expression was tested under different induction times and temperatures. Polyacrylamide gel electrophoresis with Coommassie staining was employed to confirm protein expression. Analysis via size exclusion chromatography showed the proteins to exist in several differently sized molecular complexes. pectrophotometric absorbance ratios of A260/A280 measured higher than expected suggesting, in the absence of fruit fly telomere DNA, the proteins bind non-specifically to nucleic acids (RNA or DNA) present In bacteria. These puzzling results lead to a model that posits DNA or RNA molecules present in bacteria serve as a landing platform to complex with MSK81 and HipHop.