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Population Genetics of Canine Heartworm (Dirofilaria immitis)
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Dirofilaria immitis, canine heartworm, is a filarial nematode that may have genetic features that favor the development of drug resistance, including rapid rates of mutation, large population sizes, and high levels of gene flow. This parasite is currently treated with macrocyclic lactone anthelminthics, and while it has not yet shown evidence for evolving resistance to these chemotherapeutic compounds, resistance has evolved in related filarial nematodes infecting ruminants and humans. Heartworm samples from domestic dogs and coyotes were obtained via donations from veterinarians and researchers across the United States. I isolated and characterized 11 microsatellite loci for canine heartworm. Using the observed distribution of alleles, I determined the amount of genetic variability and quantified the partitioning of genetic variance. In conjunction with microsatellite data, specific mitochondrial (cox1) and Wolbachia (wsp and ftsZ) loci were used to genotype a subset of host taxa. Results indicate a lack of mitochondrial diversity and maximum likelihood trees show no discernable geographic patterning on a continental scale. This is not unexpected in a Wolbachia-infected organism like D. immitis as this bacterium has been shown to purge mitochondrial diversity in numerous model systems. After establishing baseline genetic parameters, a model of population dynamics was created to answer questions about the potential spread of drug resistance alleles. In the absence of selection, gene flow between subpopulations drives the dispersal of drug resistance alleles. Fixation time is directly proportional to selection pressure. When resistance alleles arise in a source population they spread more rapidly than if they arise in a sequestered population.
Modern Time: Photography and Temporality
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This dissertation explores the fluid relationship of photography to time. Many theorists have noted that photography has a distinctive manner of representing temporality. Roland Barthes, for example, wrote that the photograph has a peculiar capacity to represent the past in the present, and thus to imply the passing of time in general. As a consequence, Barthes argued, all photographs speak of the inevitability of our own death in the future. Moreover, he linked photography's peculiar temporality to its capacity for a certain kind of realism: "false on the level of perception, true on the level of time." Barthes's analysis poses a challenge to all commentators on photography - what exactly is photography's relationship to time, and by extension, to reality? This dissertation addresses that two-part question by analyzing in detail a sample of understudied vernacular photographic practices. Rather than provide a comprehensive, and necessarily incomplete, study of every possible way in which photography can relate to time, this study instead focuses on a number of in-depth analyses of specific photographic practices. These practices represent time in at least three distinct ways: as narrative time, device-altered time, and composite time. My study examines the motivations for photography's insistent struggle to reorganize time's passage, to freeze or slow it for a moment, or to give form to time's fluctuating conditions. I suggest that this struggle is both symptomatic of modernity as a general phenomenon and a manifestation of the photographic medium's conditional relationship to reality, a relationship which arguably has been complicated by the use of digital technology. This dissertation examines photography's unique capacity to represent the passage of time with a degree of elasticity, simultaneity, and abstraction. The medium's ability to represent many levels of temporal experience and indexical slippage, I argue, illustrates photography's potential to relate to and reflect the complexities of modern consciousness. This dissertation also exemplifies the need for a new kind of history - one that addresses the multiple identities of "the photographic" rather than simply "the photograph." This work is a contribution to that project.
Fostering Adolescents: A Foster Parent Perspective on Raising Adolescents
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Dr. Harriet Goodman
Abstract FOSTERING ADOLESCENTS: A FOSTER PARENT PERSPECTIVE ON RAISING ADOLESCENTS IN FOSTER CARE by William Caine Bell Adviser: Professor Harriet Goodman The U.S. Adoptions and Foster Care Analysis and Reporting System indicates adolescents comprise more than 45% of the total foster care population. They are approximately 40% of new placements into foster care but represent less than 20% of children adopted from foster care each year. This exploratory study sought to illuminate the voices of foster parents raising adolescents in their homes. The study identified foster parents' perspectives on (a) policy improvement needs from the State child welfare system, (b) assistance required from the State to improve adult outcomes for adolescents in their care, and (c) training parents needed to be successful in fostering adolescents. Utilizing semistructured interviews, this qualitative study examined the experiences of 17 foster families raising teenagers in family foster care settings. The sample was primarily White and middle class; all informants were King County, Washington, residents. Study participants had an average of 17 years as foster parents and had collectively fostered more than 3,000 youth. Key findings suggest that knowledge of the motivations of foster parents provides useful information to improve recruitment, training, and support strategies for child welfare systems. Foster parents who were successful with adolescents expanded their role beyond the basic requirements of the State system. Consistent, easily accessible respite services were critical to maintaining successful foster parenting for adolescents. Results suggest a need for future research to examine perspectives of other stakeholders to improve adult outcomes for adolescents emancipating from foster care. These include social workers, adolescents in foster care, systems administrators, and birth parents. Additional inquiry should explore the relationships between foster parents and young adults formerly in their care and how these interactions affect their life outcomes. Finally, more exploration would illuminate the potential for child welfare systems and other community institutions to promote resiliency in youth in foster care. This study describes two midlevel theories emerging from the voices of study participants: (a) features of foster parents and child welfare institutions that promote risk or resilience for adolescents aging out of foster care and (b) fostering the future for adolescents in foster care: a path toward hope and improved outcomes.
Luti Masculinity in Iranian Modernity, 1785-1941: Marginalization and the Anxieties of Proper Masculine Comportment
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Middle Eastern Studies
This paper offers a genealogy of changing conceptualizations and performances of masculinity in 19th and early to mid-20th century Iran, and examines in particular a unique group of masculine subjects known as the lutis. The first component of the analysis traces the historical lineage of these lutis, situating their emergence out of Persian Sufi brotherhoods, bandit clans (`ayyar), and guild-like organizations (futuwwa) from the period of the 15th to the 19th century CE. This section provides an account of the most pertinent and distinguishing rites, attitudes, and practices of the lutis, most notably their involvement in the tradition of Iranian wrestling (koshti pahlavani) as performed in so-called Houses of Strength (zurkhaneh). In reflecting on their specific practices, this account reveals the deep imbrication of the lutis with a particular spiritual and martial mode of masculinity; expressed as the state of being javanmard or of having javanmardi (literally, "youngmanliness"). The second component of the analysis demonstrates how, from the late-19th century, the javanmardi embodiments, social enactments and sartorial comportments of the lutis came to stand in increasing tension with new norms of manliness (mardanegi) promoted in Iranian governmental and societal discourses of modernization. The section proceeds to show how an intensification of these discourses and their accompanying policies, particularly during the Iranian Constitutional Revolution (1905-1911), would signify the lutis as a menacing, counter-normative and anxiety-provoking antipode to the (attempted) formation of a unifying national Iranian masculine gender identity, a new conception of manhood defined by compulsory heterosexuality, monogamous marriage, `rational' political roles and Westernizing sartorial presentations. The significatory processes of the Qajar (1785-1925) and first Pahlavi periods (1925-1941) would gradually produce a narrative of the lutis as deviant, chaotic, violent, and sexually ambiguous subjects, a distinctly non-normative measure of manhood in the Iranian political and cultural imaginary. Employing critical and queer theoretical approaches to the historical formation of gender and sexuality, this paper thus attempts to draw out the phenomenologically lived experience of the lutis as excluded masculine subjects while also situating the development of normative conceptions of manhood and masculinity into broader histories of the critical formation of modernity in Iran.
The Road to Recovery: A Neural Characterization of Cocaine Abstinence
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Cocaine addiction is a significant public health issue with an outsized effect on the individual and society at large. A principal reason for the immense social and personal costs associated with cocaine addiction is the difficulty in remaining abstinent. Utilizing diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI), current cocaine dependence has been associated with deficits in white matter integrity and atypical neural activation in multiple cognitive control regions. However, while the neurobiological and behavioral deficits associated with current cocaine dependence have been well-characterized, it is relatively unknown if these deficits persist after the cessation of cocaine use. To elucidate neurobiological functioning during cocaine abstinence, we conducted three experiments utilizing either DTI or fMRI methodology in cocaine dependent (CD) individuals at varying periods of abstinence. The results of these investigations show that as a group, abstinent CD individuals do not display the same neurobiological deficits as current users. We speculate that the absence of these deficits may be partly due to the intensive drug-treatment programs the participants were enrolled in. However, when we conducted subject-level examinations, we found that abstinent CD individuals displayed neurobiological functioning related to the duration of abstinence. We postulate then that continued abstinence may be responsible for an amelioration of neurobiological deficits or reflect preexisting differences that allow for extended abstinence. Additionally, we observed participant-level differences that were not a function of duration of abstinence leading us to speculate that recovery occurs at temporally different rates in some individuals. Overall, it appears that while a majority of recovering individuals do not display the neurobiological deficits associated with current cocaine users, there exists a subset of individuals that continue to display these deficits. We hypothesize that those individuals who continue to display neurobiological deficits will have the greatest risk of cocaine relapse.
Consonantal voicing effects on vowel duration in Italian-English bilinguals
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This project reported in this dissertation analyzes phonetic details of the speech patterns in one of New York's bilingual communities, asking whether a bilingual speaker can attain native-like proficiency in both languages and the extent to which authenticity — maintenance of language-specific settings — is sustainable. Researchers have established that Italian and English differ strikingly in their characteristic time settings for vowel durations: durations are greater for vowels preceding voiced consonants, e.g., cab, rather than voiceless, e.g., cap. This duration difference, termed the consonantal voicing effect (CVE), is notably greater for English than for Italian. The greater magnitude of the CVE found with English is considered to be a phonological enhancement of a basic phonetic process. Utilizing a speech production task, the study reported compares the performance of Italian-born bilinguals for whom English was acquired in adulthood, as a second language, with that of U.S.-born speakers who experienced simultaneous acquisition of their languages (albeit in an English-dominant setting). In separate sessions for each language, speakers produced utterances in which the target word, situated inside a carrier phrase, contrasted in [voice] value for the post-vocalic consonant, e.g., Say the word « ___ » to me. Stimuli were familiar words selected to sample the vowel inventories for each language and for which the voicing contrast was realized through the inventory of stops common to both languages. Analyses revealed no evidence of influence of the second language on the CVE for the first language for either group, despite an extended immersion period in an English-language environment for the foreign-born speakers and simultaneous exposure to both languages from birth for the U.S.-born speakers. But crucially, there was evidence of an influence of the first language in the timing settings found for the CVE in the second language, for both speaker groups: the foreign-born speakers managed to increase the magnitude of the CVE-English but failed to fully implement the phonological mechanism consistent with larger CVE values for that language; and the U.S.-born speakers managed to reduce the magnitude of the CVE-Italian but failed to fully suppress that same mechanism. Results are discussed in relation to language-specific timing patterns and the extent to which a dominant language may influence production in the non-dominant language.
Where political extremists and greedy criminals meet: A comparative study of financial crimes and criminal networks in the United States
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Financial crime poses a serious threat to the integrity and security of legitimate businesses and institutions, and to the safety and prosperity of private citizens and communities. Experts argue that the profile of financial offenders is extremely diversified and includes individuals who may be motivated by greed or ideology. Islamic extremists increasingly resort to typical white-collar crimes, like credit card and financial fraud, to raise funds for their missions. In the United States, the far-right movement professes its anti-government ideology by promoting and using a variety of anti-tax strategies. There is evidence that ideologically motivated individuals who engage in financial crimes benefit from interactions with profit-driven offenders and legitimate actors that provide resources for crime in the form of knowledge, skills, and suitable co-offenders. This dissertation sheds light on the nexus between political extremism and profit-driven crime by conducting a systematic study of financial crime cases involving Islamic extremists, domestic far-rightists, and their non-extremist accomplices prosecuted by federal courts in 2004. Attribute and relational data were extracted from the U.S. Extremist Crime Database (ECDB), which is the first open-source relational database that provides information on all extremist crimes, violent and non-violent, ideological and routine crimes, since 1990. A descriptive analysis was conducted comparing schemes, crimes, and techniques used by far-rightists, Islamic extremists, and non-extremists, before moving into an in-depth social network analysis of their relational ties in co-offending, business, and family networks. The descriptive findings revealed considerable differences in the modus operandi followed by far-rightists and Islamic extremists as well as the prosecutorial strategies used against them. The subsequent exploratory and statistical network analyses, however, revealed interesting similarities, suggesting that financial schemes by political extremists occurred within similarly decentralized, self-organizing structures that facilitated exchanges between individuals acting within close-knit subsets regardless of their ideological affiliation. Meaningful interactions emerged between far-rightists and non-extremists involved in business ventures and within a tax avoidance scheme, indicating that the crime-extremism nexus was more prevalent within far-right settings compared to Islamic extremist ones. The findings were discussed in light of their implications for criminological theories, criminal justice and crime prevention policies, and methodological advances.
Pedagogies of Happiness: What and How Self-Help, Positive Psychology, and Positive Education Teach about Well-Being
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Pedagogies of Happiness: What and How Self-Help, Positive Psychology, and Positive Education Teach about Well-Being introduces humanities scholars to the rapidly expanding discipline of positive psychology, and argues that literary scholars, cultural theorists, rhetoricians, and educators must learn about and play a role in shaping the important political and social consequences of positive psychology's research on subjective well-being. The project first explores key rhetorical sites of the self-help genre and positive psychology discipline, and parses their pedagogy, potentiality, promises, and problems. While these movements claim to benefit not only individuals but also society, they are based on a number of unacknowledged--and often overlapping--values that suggest otherwise: they are individualistic, instrumentalized, decontextualized, non-dialogic, non-reflexive, politically conservative, and remedial. Therefore, self-help and positive psychology's versions of happiness, well-being, and flourishing preserve and serve the status quo. After highlighting these problems, Pedagogies of Happiness explores how research into subjective well-being is used to effect crucial policy decisions that affect teaching as well as student learning conditions. The second half of the project presents current efforts to create educational curricula that teach and institutionalize well-being and complicates the assumptions, values, and goals behind so-called "positive education." The final chapter synthesizes the project's various critiques by tracing how self-help and positive psychology rhetoric and pedagogy merge powerfully in a specific positive education initiative: Comprehensive Soldier Fitness (CSF), a mandatory United States Army program for building resiliency, psychological fitness, and well-being in soldiers. Drawing on composition and rhetoric, the scholarship of teaching and learning, and utopian theory, Pedagogies of Happiness concludes by sketching pedagogical alternatives to positive education's contradictory and conservative curricula, and inserts a utopian critique, arguing that future discussions need to consider not only individual resiliency but also social justice.
FUNCTIONAL CHARACTERIZATION OF THE PLANT 15-CIS-ZETA-CAROTENE ISOMERASE Z-ISO
Jesus Beltran Zambrano
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Vitamin A deficiency is a widespread health issue in the tropics. To solve this issue, efforts are underway to increase provitamin A carotenoids such as B-carotene in staple crops which can be achieved by breeding, metabolic engineering or a combination of both approaches. However, rational strategies to improve carotenoid content in crops require sufficient knowledge of pathway regulation. Therefore, to better understand how plants synthesize provitamin A and to guide metabolic engineering strategies in crops such as maize, the functional characterization of the new z-carotene isomerase (Z-ISO) is of significant importance. Z-ISO was recently discovered in maize and Arabidopsis (Chen et al., 2010). This new enzyme is a 15-cis-z-carotene isomerase present in all plants, diatoms and algae. Z-ISO is required in both green and non-green tissues including roots and the seed endosperm which is target for provitamin A biofortification. In this dissertation, to gain a better understanding of the role of Z-ISO in the isomerization of 15-cis-z-carotene, the Z-ISO polypeptide was biochemically characterized using extensive spectroscopy and its function was examined by developing an in vitro enzymatic assay and by an in vivo complementation system in Escherichia coli. Bioinformatic tools modeled Z-ISO as an integral membrane and heme or non-heme iron binding protein. Therefore, using the Z-ISO polypeptide sequence, we selected conserved putative residue ligands for heme and non-heme iron and mutagenized them to Alanine. These Z-ISO mutant versions were tested for enzymatic function using an E. coli complementation system. These experiments showed that from all the conserved histidines present in Z-ISO, two (H150 and H266) as well as one aspartic acid residue (D294), were essential for isomerase activity. The only cysteine (C263) residue present in Z-ISO was not required for activity. These results are in good agreement with the predicted Z-ISO model where the locations for H150 and H266 are consistent with the coordination of a common factor. Maize Z-ISO was also over-expressed and purified as a TEV protease-cleavable, maltose binding protein (MBP) fusion (MBP::Z-ISO). An in vitro assay utilizing substrate containing liposomes was developed to test Z-ISO activity. The conversion of the substrate 9,15,9'-tri-cis-z-carotene into the product 9,9'-di-cis-z-carotene by Z-ISO proceeded under reducing conditions but not under oxidizing conditions. MBP::Z-ISO purified protein was also tested for the presence of metals. Using inductively coupled plasma optical emission spectrometry (ICP-OES) iron was detected but there were no significant levels of Ca, Cu, Mg, Mn, Mo, or Zn. Therefore, we concluded that Z-ISO is a metalloprotein. E. coli culture pellets expressing MBP::Z-ISO are brown consistent with the presence of iron or heme. The presence of heme in purified MBP::Z-ISO was evaluated using heme staining and pyridine hemochrome assays. Heme staining of protein separated in SDS-PAGE gels revealed that MBP::Z-ISO and Z-ISO contain heme while MBP alone does not. Moreover, hemochrome assays showed the presence of heme b in Z-ISO. The UV-visible absorption spectrum of the intact, as isolated Z-ISO confirmed the presence of heme b in the oxidized, ferric Fe (III) state. Also, the spectrum of reduced Z-ISO is similar to that of cytochromes containing heme b with two axial histidine ligands and the reduced heme b binds carbon monoxide (CO). Z-ISO was also characterized using electron paramagnetic resonance (EPR). An X-band spectrum of the MBP::Z-ISO fusion detected high-spin ferric heme (e.g. heme b with a single histidine ligand), multiple low-spin heme species, and a non-heme iron center. EPR also indicated the presence of two low-spin heme species and that one of these hemes might have a bis-histidine coordination and the other might have a histidine-cysteine axial coordination. Reduced Z-ISO also binds NO which is consistent with the binding of CO. To gain more details on the heme cofactor, the same sample used in the EPR experiments was used to characterize the heme iron in MBP::Z-ISO using magnetic circular dichroism (MCD) which detects only heme iron. MCD characterization showed that Z-ISO has two ligand pairs (His/His and His/Cys), a result that is consistent with the EPR results. MCD experiments also showed a redox-dependent change in ligand (Cys-His) coordination of a low-spin heme b. Our data also suggested the existence of a high-spin, 5-coordinate, His-ligated heme which was detected by EPR and as a minor species by MCD. We hypothesized that substrate could bind to this intermediate or that substrate displaces an axial ligand to coordinate with the heme iron. MCD, EPR, and UV-Vis analysis showed that exogenous ligands bind the Fe(II) state but it was not known whether an exogenous ligand can displace an axial ligand when the heme is in the Fe(III) state. To test this possibility we utilized addition of cyanide (CN-), which binds preferably to the ferric rather than the ferrous heme. CN- was added to both the as isolated (oxidized) Fe(III) ferric enzyme and to the Fe(II) (dithionite-reduced) ferrous enzyme. UV-Vis absorption spectra indicated CN- binding to the ferric Fe(III) heme which suggest that Z-ISO can also bind exogenous ligands in the oxidized form. Taken together our data suggest that heme is essential for Z-ISO activity. The presence of heme and its requirement for Z-ISO activity are surprising since heme is not often described in isomerization reactions. Based on our results, we propose a mechanism for Z-ISO function.
Sex and the Nation: Sexuality and Criminal Justice in Revolutionary Mexico, 1920-1940
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This dissertation examines the way in which notions of sexuality were interpreted and reworked by the criminal justice system and the citizens that fell under its purview during the decades immediately following the revolutionary struggle in Mexico. The dissertation examines legal and criminological literature as well as a sample of four hundred and fourteen cases drawn from Mexico City criminal and juvenile courts. The cases include criminal offenses such as rape and seduction, and homosexuality, prostitution, incest, indecent behavior and indiscipline in the home among minors. It traces the foreign and national influences that shaped the Mexican criminological establishment's views on sexuality and argues that despite major reforms to the criminal justice system after the Revolution, many continuities existed between Revolutionary legal approaches to sexuality and those of its Profirian predecessor. At the same time, the dissertation examines closely the way in which court officials during the 1920s and 1930s constructed arguments and reached court decisions. In this way, the dissertation shows the way in which old notions of honor and sexual purity were put to the test under the new Revolutionary regime. It reveals how traditional understandings of sexuality could coexist with "modern" notions. An examination of the cases reveals what conflicts could occur between reform-minded government officials and the general public that sought the intervention of the courts to solve disputes of a sexual nature. Finally, the dissertation shows how the Revolutionary criminal justice system could only be successful when the goals of the public officials coincided or, at the very least overlapped with those of the citizens that were involved in the court trials.