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This thesis is an investigation of genealogical inquiry, but rather than interpreting genealogical activity first and foremost as a branch of history, I analyse genealogy as a form of semi-autobiographical narrative about the self. Instead of viewing the use of archives primarily as a marker of historical scholarship, I investigate the archive as a shared space or horizon in which stories about the self and one’s descent are enacted, a theatrical space in which the ‘narratability’ of the self and of others is exposed. The thesis is divided into three chapters. The first chapter provides a ‘heritagraphical’ overview of genealogical knowledge where I argue that the pre-war history of genealogy is worth investigating; genealogy is a diverse cultural practice with its own history, historical agents and situated communities. The second chapter, ‘Archivization of Genealogical Knowledge’, explores the development of genealogy in the nineteenth and early twentieth centuries by investigating the circulation of genealogical knowledge in the public sphere of antiquarian print culture, gender and genealogy, the connections between eugenics, genealogy and archives, and the influence of the American diaspora upon the production and consumption of genealogy within Britain. The third chapter, ‘Narrating the Genealogical Self’, develops the metaphor of the archive as a theatre of self-identity by exploring several texts, including A Family Record (1932), Roots (1976) and the television programmes, Who Do You Think You Are? and Motherland: A Genetic Journey. In doing so, ‘the archive’ is expanded to not only include the traditional notion of an institutional repository of written documentary sources, but also more recent conceptions of the archive as a body of immutable biological code, as the consignation of unique hidden traces, or as the compilation of autobiographical memory. I conclude by arguing that genealogy can represent a desire for semi-autobiographical narrative through which the self is revealed as both a unified self and as a ‘unique existent’. This is how archives disclose to us who we are. In this way, this thesis demonstrates that archives have another function than that of providing tangible evidence of business transactions; they have an ontological function of being necessary ‘other’ evidentiary witnesses, revealing the narratability of who we are as unique historical beings, who, nevertheless, do not stand alone.

Combining cesium (Cs) bombardment with positive secondary molecular ion detection (MCs+) can extend the analysis capability of Secondary Ion Mass Spectrometry (SIMS) from the dilute limit (<1%) to matrix elements. The MCs+ technique has had great success in quantifying the sample composition of III-V semiconductors as well as dopants and/or impurities; however, it has been less effective at reducing the matrix effect for IV compounds, particularly Si-containing compounds, due to Cs overloading at the surface during the analysis from the Cs primary ion beam. The Cs overloading issue is attributable to the mobility and relocation of the implanted Cs to the surface; this effect happens almost instantaneously. Once the surface is overloaded with Cs, the excess Cs begins to reneutralize the ionization Cs and, as a result, the MCs+ technique is ineffective at reducing the matrix effect. This research provides new insights for improving the MCs+ technique and elucidating the Cs mobility. A combination of multiple experimental techniques and theoretical modeling was implemented to assess the Cs retention, up-take, and distribution differences between group III-V and IV materials. Early experiments revealed a temperature-dependent component of the Cs mobility, prompting an investigation of this phenomenon. Therefore, we designed, built, and installed a variable temperature stage for our SIMS with temperatures ranging from -150 to 300 C. This enabled us to study the temperature-dependent component of the Cs mobility and the effect it has on the secondary ion emission processes. Additionally, a method was devised to quantify the amount of neutralization and ionization due to the relocated Cs. The results allow for a more thorough understanding of the material dependence on the Cs+-sample interaction and the temperature component of the Cs mobility. / Ph. D.

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To learn about computer operating systems, students at Virginia Tech implement a command-line shell in their Computer Systems course. Successfully implementing the shell requires a deep understanding of operating system abstractions and interactions. Students often struggle with the project because subtle errors can take hours to debug. In this work, we developed two hybrid domain-specific analysis tools to pinpoint the root causes of student errors: EshMD and ShellTrace. The EshMD tool models common errors in the shell and checks the student code against those models. To accomplish this, it monitors the specific calls the program is making and correlates those with expected changes in its environment. Students' errors are shown directly in the source code. The concept of EshMD can be applied to other programming projects by observing and modeling common bugs during implementation. The ShellTrace tool dynamically creates a specification from a reference solution based on how the reference solution makes use of operating system resources and then uses this specification to check that a student solution is functionally identical. The ShellTrace concept can be applied to other programs that exhibit similar resource dependencies. We deployed these tools in an undergraduate computer systems class and evaluated our tools based on the number of bugs detected and the students' perceptions of usefulness. We found that the tools detected a significant number of bugs and that the majority of students that made use of the tools found them valuable in debugging their submissions. / Master of Science / To learn about computer operating systems, students at Virginia Tech implement a command-line shell in their junior-level Computer Systems course. A command-line shell is a computer program that allows the user of a computer to run other programs by typing in the program names. The command-line shell will then run those programs on the user’s behalf. The command-line shell project requires students to understand and use the abstractions that the underlying operating system provides to a computer program. Students often struggle with the project because subtle errors in their implementation can take hours to address. In this work, we developed two analysis tools to pinpoint the root cause of student errors: EshMD and ShellTrace. The EshMD tool models common errors in the command-line shell and checks the student code against those models. Students’ errors are shown by directly pointing to the error locations in their code. The ShellTrace tool dynamically creates a project specification from a solution written by the course staff and checks that a student solution meets the specification. Generating from the staff solution allows checking the student solution without having to encode the specific project requirements into the tool itself. We deployed these tools in an undergraduate computer systems class and evaluated our tools based on the number of errors detected and the students’ perceptions of usefulness. We found that the tools detected a significant number of errors and that the majority of students that made use of the tools found them valuable in finding and fixing the errors in their submissions.

In the last two years, CS as a school subject has gained a lot of attention worldwide, although different countries have differing approaches to and experiences of introducing CS in schools. This paper reports on a study comparing current trends in CS at school, with a major focus on two countries, Germany and UK. A survey was carried out of a number of teaching professionals and experts from the UK and Germany with regard to the content and delivery of CS in school. An analysis of the quantitative data reveals a difference in foci in the two countries; putting this into the context of curricular developments we are able to offer interpretations of these trends and suggest ways in which curricula in CS at school should be moving forward.

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Delivery of complex molecules such as peptides, proteins, oligonucleotides and plasmids is an intensively studied subject, which has attracted considerable medical and pharmaceutical interest. Encapsulation of these molecules with biodegradable polymers represents one way of overcoming various problems associated with the conventional delivery of macromolecules, for example instability and short biological half-life. The use of carriers made of hydrophilic polysaccharides such as chitosan, has been pursued as a promising alternative for improving the transport of biologically active macromolecules across biological surfaces. The development of nanoparticles as a delivery system also has major advantages of achieving possible drug protection, controlled release and drug targeting by either a passive or an active means. The aim of this study was to develop a simple and effective method to formulate biodegradable nanoparticles for the delivery of a model protein-bovine serum albumin (BSA) and an angiogenesis inhibitor, arginine-rich hexapeptide (ARE peptide). Major factors which determine nanoparticle formation and loading of the protein and the peptide as well as the underlying mechanisms controlling their incorporation and release characteristics were investigated. The preparation technique, based on the complex coacervation process, is extremely mild and involves the mixture of two aqueous solutions (chitosan and dextran sulfate) at room temperature. The formation of nanoparticles is dependent on the concentrations of chitosan (CS) and dextran sulfate (DS); particles with size, of 257 to 494nm can be obtained with 0.1%w/v solutions of CS and DS. Zeta potential of nanoparicles can be modulated conveniently from -34.3mV to +52.7mV by varying the composition of the two ionic polymers. / Both bovine BSA and the ARH peptide were successfully incorporated into CS-based nanoparticles, mainly via an electrostatic interaction, with entrapment efficiency up to 100% and 75.9% for the protein and peptide respectively. Incorporation of both the protein and peptide into nanoparticles resulted in an increase in size suggesting their close association with the nanoparticle matrix material. The difference in sign and magnitude of zeta potential of empty and macromolecules-loaded nanoparticles supports the hypothesis that protein and peptide association with nanoparticles can be modulated by their ionic interaction with the oppositely charged ionic polymer (DS) in the nanoparticles. The release of BSA from the nanoparticles was very slow in water compared to that in l0mM phosphate buffer pH 7.4; whereas, ARH peptide showed extremely low level of release in water at the low ratio of DS but at the high ratio of DS, its release was in biphasic fashion, with an initial burst effect followed by an almost constant but very slow release up to 7 days in both water and 1 OmM phosphate buffer (pH 7.4). It was found that, unlike ARH peptide, the percentage of BSA released was relatively slower for the nanoparticles with a high ratio of DS. It is speculated that this difference in the release behaviour of BSA and ARH peptide, could be due to the effect of molecular size of the compounds and their interaction with the polymer matrix of the nanoparticle. The results of this study suggest that these novel CS/DS nanoparticulate system, prepared by a very mild ionic crosslinking technique, have potential to be a suitable carrier for the entrapment and controlled release of peptides and proteins.