Complex Adaptive Systems & Urban Morphogenesis:

This thesis looks at how cities operate as Complex Adaptive Systems (CAS). It focuses on how certain characteristics of urban form can support an urban environment's capacity to self-organize, enabling emergent features to appear that, while unplanned, remain highly functional. The research is predicated on the notion that CAS processes operate across diverse domains: that they are ‘generalized' or ‘universal'. The goal of the dissertation is then to determine how such generalized principles might ‘play out' within the urban fabric. The main thrust of the work is to unpack how elements of the urban fabric might be considered as elements of a complex system and then identify how one might design these elements in a more deliberate manner, such that they hold a greater embedded capacity to respond to changing urban forces. The research is further predicated on the notion that, while such responses are both imbricated with, and stewarded by human actors, the specificities of the material characteristics themselves matter. Some forms of material environments hold greater intrinsic physical capacities (or affordances) to enact the kinds of dynamic processes observed in complex systems than others (and can, therefore, be designed with these affordances in mind). The primary research question is thus:   What physical and morphological conditions need to be in place within an urban environment in order for Complex Adaptive Systems dynamics arise - such that the physical components (or ‘building blocks') of the urban environment have an enhanced capacity to discover functional configurations in space and time as a response to unfolding contextual conditions?   To answer this question, the dissertation unfolds in a series of parts. It begins by attempting to distill the fundamental dynamics of a Complex Adaptive System. It does so by means of an extensive literature review that examines a variety of highly cited ‘defining principles' or ‘key attributes' of CAS. These are cross-referenced so as to extract common features and distilled down into six major principles that are considered as the generalized features of any complex system, regardless of domain. In addition, this section considers previous urban research that engages complexity principles in order to better position the distinctive perspective of this thesis. This rests primarily on the dissertation's focus on complex urban processes that occur by means of materially enabled in situ processes. Such processes have, it is argued, remained largely under-theorized. The opening section presents introductory examples of what might be meant by a ‘materially enabling' environment.   The core section of the research then undertakes a more detailed unpacking of how complex processes can be understood as having a morphological dimension. This section begins by discussing, in broad terms, the potential ‘phase space' of a physical environment and how this can be expanded or limited according to a variety of factors. Drawing insights from related inquiries in the field of Evolutionary Economic Geography, the research argues that, while emergent capacity is often explored in social, economic, or political terms, it is under-theorized in terms of the concrete physical sub-strata that can also act to ‘carry' or ‘moor' CAS dynamics. This theme is advanced in the next article, where a general framework for speaking about CAS within urban environments is introduced. This framework borrows from the terms for ‘imageability' that were popularized by Kevin Lynch: paths, edges, districts, landmarks, and nodes. These terms are typically associated with physical or ‘object-like features' of the urban environment – that is to say, their image. The terminology is then co-opted such that it makes reference not simply to physical attributes, but rather to the complex processes these attributes enable. To advance this argument, the article contrasts the static and ‘imageable' qualities of New Urbanism projects with the ‘unfolding' and dynamic qualities of complex systems - critiquing NU proponents as failing to appreciate the underlying forces that generate the environments they wish to emulate. Following this, the efficacy of the re-purposed ‘Lynchian' framework is tested using the case study of Istanbul's Grand Bazaar. Here, specific elements of the Bazaar's urban fabric are positioned as holding material agency that enables particular emergent spatial phenomena to manifest. In addition, comparisons are drawn between physical dynamics unfolding within the Bazaar's morphological setting (leading to emergent merchant districts) and parallel dynamics explored within Evolutionary Economic Geography).   The last section of the research extends this research to consider digitally augmented urban elements that hold an enhanced ability to receive and convey information. A series of speculative thought-experiments highlight how augmented urban entities could employ CAS dynamics to ‘solve for' different kinds of urban optimization scenarios, leading these material entities to self-organize (with their users) and discover fit regimes. The final paper flips the perspective, considering how, not only material agency, but also human agency is being augmented by new information processing technologies (smartphones), and how this can lead to new dances of agency that in turn generate novel emergent outcomes.   The dissertation is based on a compilation of articles that have, for the most part, been published in academic journals and all the research has been presented at peer-reviewed academic conferences. An introduction, conclusion, and explanatory transitions between sections are provided in order to clarify the narrative thread between the sections and the articles. Finally, a brief ‘coda' on the spatial dynamics afforded by Turkish Tea Gardens is offered

Considering how morphological traits of urban fabric create affordances for complex adaptation and emergence

This paper examines how physical and material properties of the urban fabric help enable the evolution of programmatically coherent spatial districts. It considers how contingent and non-linear processes intertwine to manifest in the unfolding of distinct sites and territories. Drawing concepts and terminology from both evolutionary economic geography and the sciences of complexity, it emphasizes how physically situated morphological traits help underpin urban processes of self-organization and emergence

HIV-Infected Prison Inmates: Depression and Implications for Release Back to Communities

High rates of both HIV and depression are seen in prison populations; depression has been linked to disease progression in HIV, risky behaviors, and medication non-adherence. Despite this, few studies have examined HIV-infected inmates with depression. We therefore conducted an exploratory study of a sample of HIV-infected inmates in North Carolina prisons (N=101) to determine what proportion of this sample screened positive for depression and whether depression was associated with different pre-incarceration characteristics or post-release needs. A high proportion of HIV infected inmates (44.5%) screened positive for depression. Depressed inmates were significantly more likely have low coping self-efficacy scores (180 vs. 214), to report having had resource needs (OR=2.91) prior to incarceration and to anticipate needing income (OR=2.81), housing (OR=4.07), transportation (OR=9.15), and assistance with adherence (OR=8.67) post-release. We conclude by discussion the implications of our findings for prison based care and effective prison release planning for HIV infected inmates

Dissolution of Primary Intimate Relationships During Incarceration and Associations With Post-Release STI/HIV Risk Behavior in a Southeastern City

Incarceration is associated with sexually transmitted infections (STIs) including human immunodeficiency virus (HIV). Incarceration may contribute to STI/HIV by disrupting primary intimate relationships that protect against high-risk partnerships

The Clinical Impact of Continuing to Prescribe Antiretroviral Therapy in Patients with Advanced AIDS Who Manifest No Virologic or Immunologic Benefit

Introduction: Despite the efficacy and tolerability of modern antiretroviral therapy (ART), many patients with advanced AIDS prescribed these regimens do not achieve viral suppression or immune reconstitution as a result of poor adherence, drug resistance, or both. The clinical outcomes of continued ART prescription for such patients have not been well characterized. Methods: We examined the causes and predictors of all-cause mortality, AIDS-defining conditions, and serious non-AIDS-defining events among a cohort of participants in a clinical trial of pre-emptive therapy for CMV disease. We focused on participants who, despite ART had failed to achieve virologic suppression and substantive immune reconstitution. Results: 233 ART-receiving participants entered with a median baseline CD4+ T cell count of 30/mm3 and plasma HIV RNA of 5 log10 copies/mL. During a median 96 weeks of follow-up, 24.0% died (a mortality rate of 10.7/100 patient-years); 27.5% reported a new AIDS-defining condition, and 22.3% a new serious non-AIDS event. Of the deaths, 42.8% were due to an AIDS-defining condition, 44.6% were due to a non-AIDS-defining condition, and 12.5% were of unknown etiology. Decreased risk of mortality was associated with baseline CD4+ T cell count ≥25/mm3 and lower baseline HIV RNA. Conclusions: Among patients with advanced AIDS prescribed modern ART who achieve neither virologic suppression nor immune reconstitution, crude mortality percentages appear to be lower than reported in cohorts of patients studied a decade earlier. Also, in contrast to the era before modern ART became available, nearly half of the deaths in our modern-era study were caused by serious non-AIDS-defining events. Even among the most advanced AIDS patients who were not obtaining apparent immunologic and virologic benefit from ART, continued prescription of these medications appears to alter the natural history of AIDS—improving survival and shifting the causes of death from AIDS- to non-AIDS-defining conditions

Locating the Places People Meet New Sexual Partners in a Southern US City to Inform HIV/STI Prevention and Testing Efforts

Places where people meet new sex partners can be venues for the delivery of individual and environmental interventions that aim to reduce transmission of HIV and other sexually transmitted infections (STI). Using the Priorities for Local AIDS Control Efforts (PLACE) methodology we identified and characterized venues where people in a southeastern US city with high prevalence of both HIV and STI go to meet new sexual partners. A total of 123 community informants identified 143 public, private and commercial venues where people meet sex partners. Condoms were available at 14% of the venues, although 48% of venue representatives expressed a willingness to host HIV prevention efforts. Interviews with 373 people (229 men, 144 women) socializing at a random sample of 54 venues found high rates of HIV risk behaviors including concurrent sexual partnerships, transactional sex and illicit substance abuse. Risk behaviors were more common among those at certain venue types including those that may be overlooked by public health outreach efforts. The systematic methodology used was successful in locating venues where risky encounters are established and reveal opportunities for targeted HIV prevention and testing programs as well as research

Timing and Duration of Incarceration and High-Risk Sexual Partnerships Among African Americans in North Carolina

Incarceration may contribute to HIV transmission by disrupting stable partnerships and promoting high-risk partnerships. We investigated incarceration and high-risk partnerships among African Americans in North Carolina (NC)