Matching Items (82)
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Description
Immunosignature is a technology that retrieves information from the immune system. The technology is based on microarrays with peptides chosen from random sequence space. My thesis focuses on improving the Immunosignature platform and using Immunosignatures to improve diagnosis for diseases. I first contributed to the optimization of the immunosignature platform

Immunosignature is a technology that retrieves information from the immune system. The technology is based on microarrays with peptides chosen from random sequence space. My thesis focuses on improving the Immunosignature platform and using Immunosignatures to improve diagnosis for diseases. I first contributed to the optimization of the immunosignature platform by introducing scoring metrics to select optimal parameters, considering performance as well as practicality. Next, I primarily worked on identifying a signature shared across various pathogens that can distinguish them from the healthy population. I further retrieved consensus epitopes from the disease common signature and proposed that most pathogens could share the signature by studying the enrichment of the common signature in the pathogen proteomes. Following this, I worked on studying cancer samples from different stages and correlated the immune response with whether the epitope presented by tumor is similar to the pathogen proteome. An effective immune response is defined as an antibody titer increasing followed by decrease, suggesting elimination of the epitope. I found that an effective immune response usually correlates with epitopes that are more similar to pathogens. This suggests that the immune system might occupy a limited space and can be effective against only certain epitopes that have similarity with pathogens. I then participated in the attempt to solve the antibiotic resistance problem by developing a classification algorithm that can distinguish bacterial versus viral infection. This algorithm outperforms other currently available classification methods. Finally, I worked on the concept of deriving a single number to represent all the data on the immunosignature platform. This is in resemblance to the concept of temperature, which is an approximate measurement of whether an individual is healthy. The measure of Immune Entropy was found to work best as a single measurement to describe the immune system information derived from the immunosignature. Entropy is relatively invariant in healthy population, but shows significant differences when comparing healthy donors with patients either infected with a pathogen or have cancer.
ContributorsWang, Lu (Author) / Johnston, Stephen (Thesis advisor) / Stafford, Phillip (Committee member) / Buetow, Kenneth (Committee member) / McFadden, Grant (Committee member) / Arizona State University (Publisher)
Created2018
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Description
This work advances structural and biophysical studies of three proteins important in disease. First protein of interest is the Francisella tularensis outer membrane protein A (FopA), which is a virulence determinant of tularemia. This work describes recombinant expression in Escherichia coli and successful purification of membrane translocated FopA. The purified

This work advances structural and biophysical studies of three proteins important in disease. First protein of interest is the Francisella tularensis outer membrane protein A (FopA), which is a virulence determinant of tularemia. This work describes recombinant expression in Escherichia coli and successful purification of membrane translocated FopA. The purified protein was dimeric as shown by native polyacrylamide gel electrophoresis and small angle X-ray scattering (SAXS) analysis, with an abundance of β-strands based on circular dichroism spectroscopy. SAXS data supports the presence of a pore. Furthermore, protein crystals of membrane translocated FopA were obtained with preliminary X-ray diffraction data. The identified crystallization condition provides the means towards FopA structure determination; a valuable tool for structure-based design of anti-tularemia therapeutics.

Next, the nonstructural protein μNS of avian reoviruses was investigated using in vivo crystallization and serial femtosecond X-ray crystallography. Avian reoviruses infect poultry flocks causing significant economic losses. μNS is crucial in viral factory formation facilitating viral replication within host cells. Thus, structure-based targeting of μNS has the potential to disrupt intracellular viral propagation. Towards this goal, crystals of EGFP-tagged μNS (EGFP-μNS (448-605)) were produced in insect cells. The crystals diffracted to 4.5 Å at X-ray free electron lasers using viscous jets as crystal delivery methods and initial electron density maps were obtained. The resolution reported here is the highest described to date for μNS, which lays the foundation towards its structure determination.

Finally, structural, and functional studies of human Threonine aspartase 1 (Taspase1) were performed. Taspase1 is overexpressed in many liquid and solid malignancies. In the present study, using strategic circular permutations and X-ray crystallography, structure of catalytically active Taspase1 was resolved. The structure reveals the conformation of a 50 residues long fragment preceding the active side residue (Thr234), which has not been structurally characterized previously. This fragment adopted a straight helical conformation in contrast to previous predictions. Functional studies revealed that the long helix is essential for proteolytic activity in addition to the active site nucleophilic residue (Thr234) mediated proteolysis. Together, these findings enable a new approach for designing anti-cancer drugs by targeting the long helical fragment.
ContributorsNagaratnam, Nirupa (Author) / Fromme, Petra (Thesis advisor) / Johnston, Stephen (Thesis advisor) / Van Horn, Wade (Committee member) / Liu, Wei (Committee member) / Arizona State University (Publisher)
Created2020
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Description
Prior to the COVID-19 global pandemic, ecotourism represented the tourism industry’s fastest growing segment with projections estimating that ecotourism would become the world’s largest tourism type by 2030. While the tourism industry will need several years to rebound, if historic trends tell us anything, it is that ecotourism will continue

Prior to the COVID-19 global pandemic, ecotourism represented the tourism industry’s fastest growing segment with projections estimating that ecotourism would become the world’s largest tourism type by 2030. While the tourism industry will need several years to rebound, if historic trends tell us anything, it is that ecotourism will continue to represent a large portion of the overall industry and will continue to grow at a rate that outpaces all other tourism types. In theory, ecotourism promotes sustainable socioeconomic development while also minimizing negative environmental impacts. Unfortunately, research suggests that this is not always true, and many examples exist of ecotourism causing more harm than good. In order to combat these potential negative impacts, the ecotourism industry has become increasingly reliant on ecotourism certification programs to act as an assessment tool that identifies ecotourism’s best practitioners while minimizing false advertising present within the industry. Despite these beliefs in the efficacy of certification, there is a lack of empirical research to actually support certification as an effective assessment tool. Furthermore, little research has been conducted that assesses the impacts that certification itself has on ecotourism businesses (both certified and uncertified) and the local communities dependent on ecotourism.
My dissertation employs a mixed methods design and combines qualitative and quantitative research methods spanning multiple geographic scales to develop an understanding of certification programs as they exist today and to discern the impacts that certification itself may cause for all those either directly or indirectly involved in ecotourism. My findings ultimately suggest that certification reform is needed if certification programs are expected to be the assessment tool ecotourism experts claim them to be. Specifically, as certification exists presently, there is: no universal guideline or standard for existing certification programs to follow, a disconnect between the advertised benefits certification offers and the actual benefits received, and a lack of market penetration both amongst ecotourists and ecotourism businesses. Each of these must be addressed before certification can live up to its full potential. Furthermore, I found that certification may impact community socioeconomic dynamics, particularly by creating or exacerbating community wealth distribution.
ContributorsDavila, Ryan (Author) / Kinzig, Ann (Thesis advisor) / Perrings, Charles (Committee member) / Collins, James (Committee member) / Schoon, Michael (Committee member) / Buzinde, Christine (Committee member) / Arizona State University (Publisher)
Created2020
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Description
Climate adaptation has not kept pace with climate impacts which has formed an adaptation gap. Increasingly insurance is viewed as a solution to close this gap. However, the efficacy and implications of using insurance in the climate adaptation space are not clear. Furthermore, past research has focused on specific actors

Climate adaptation has not kept pace with climate impacts which has formed an adaptation gap. Increasingly insurance is viewed as a solution to close this gap. However, the efficacy and implications of using insurance in the climate adaptation space are not clear. Furthermore, past research has focused on specific actors or processes, not on the interactions and interconnections between the actors and the processes. I take a complex adaptive systems approach to map out how these dynamics are shaping adaptation and to interrogate what the insurance climate adaptation literature claims are the successes and pitfalls of insurance driving, enabling or being adaptation. From this interrogation it becomes apparent that insurance has enormous influence on its policy holders, builds telecoupling into local adaptation, and creates structures which support contradictory land use policies at the local level. Based on the influence insurance has on policy holders, I argue that insurance should be viewed as a form of governance. I synthesize insurance, governance and adaptation literature to examine exactly what governance tools insurance uses to exercise this influence and what the consequences may be. This research reveals that insurance may not be the exemplary adaptation approach the international community is hoping for. Using insurance, risk can be reduced without reducing vulnerability, and risk transfer can result in risk displacement which can reduce adaptation incentives, fuel maladaptation, or impose public burdens. Moreover, insurance requires certain information and legal relationships which can and often do structure that which is insured to the needs of insurance and shift authority away from governments to insurance companies or public-private partnerships. Each of these undermine the legitimacy of insurance-led local adaptation and contradict the stated social justice goals of international calls for insurance. Finally, I interrogate the potential justice concerns that emerged through an analysis of insurance as a form of adaptation governance. Using a multi-valent approach to justice I examine a suite of programs intended to support agricultural adaptation through insurance. This analysis demonstrates that although some programs clearly attempted to consider issues of justice, overall these existing programs raise distributional, procedural and recognition justice concerns.
ContributorsLueck, Vanessa (Author) / Klinsky, Sonja (Thesis advisor) / Schoon, Michael (Thesis advisor) / Eakin, Hallie (Committee member) / Arizona State University (Publisher)
Created2020
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Description
Institutions (rules, norms, and shared strategies) are social feedback systems that structure actors’ decision-making context. It is important to investigate institutional design to understand how rules interact and generate feedbacks that affect robustness, i.e., the ability to respond to change. This is particularly important when assessing sustainable use/conservation trade-offs that

Institutions (rules, norms, and shared strategies) are social feedback systems that structure actors’ decision-making context. It is important to investigate institutional design to understand how rules interact and generate feedbacks that affect robustness, i.e., the ability to respond to change. This is particularly important when assessing sustainable use/conservation trade-offs that affect species’ long-term survival. My research utilized the institutional grammar (IG) and robust institutional design to investigate these linkages in the context of four international conservation treaties.

First, the IG was used to code the regulatory formal treaty rules. The coded statements were then assessed to determine the rule linkages and dynamic interactions with a focus on monitoring and related reporting and enforcement mechanisms. Treaties with a regulatory structure included a greater number and more tightly linked rules related to these mechanisms than less regulatory instruments. A higher number of actors involved in these activities at multiple levels also seemed critical to a well-functioning monitoring system.

Then, drawing on existing research, I built a set of constitutive rule typologies to supplement the IG and code the treaties’ constitutive rules. I determined the level of fit between the constitutive and regulatory rules by examining the monitoring mechanisms, as well as treaty opt-out processes. Treaties that relied on constitutive rules to guide actor decision-making generally exhibited gaps and poorer rule fit. Regimes which used constitutive rules to provide actors with information related to the aims, values, and context under which regulatory rules were being advanced tended to exhibit better fit, rule consistency, and completeness.

The information generated in the prior studies, as well as expert interviews, and the analytical frameworks of Ostrom’s design principles, fit, and polycentricity, then aided the analysis of treaty robustness. While all four treaties were polycentric, regulatory regimes exhibited strong information processing feedbacks as evidenced by the presence of all design principles (in form and as perceived by experts) making them theoretically more robust to change than non-regulatory ones. Interestingly, treaties with contested decision-making seemed more robust to change indicating contestation facilitates robust decision-making or its effects are ameliorated by rule design.
ContributorsBrady, Ute (Author) / Anderies, John M. (Thesis advisor) / Schoon, Michael (Committee member) / Minteer, Ben A. (Committee member) / Gerber, Leah (Committee member) / Siddiki, Saba (Committee member) / Arizona State University (Publisher)
Created2020
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Description
This dissertation focuses on water security in terms of sustaining socio-economic development, livelihoods, and human well-being. Using the double exposure framework, I analyze the combined effect of climate change and economic development on water security in the Philippines. There is a need to examine how the combination of these two

This dissertation focuses on water security in terms of sustaining socio-economic development, livelihoods, and human well-being. Using the double exposure framework, I analyze the combined effect of climate change and economic development on water security in the Philippines. There is a need to examine how the combination of these two processes aggravate existing inequalities related to water security among different groups of people, and also analyze how these two processes can combine to increase stakeholders’ vulnerability to water-related shocks and stresses. The Philippines has been rated as one of the countries that is most vulnerable to climate change due to its exposure to extreme climate events and sea level rise. At the same time, the Philippines is currently undergoing an economic transition from a predominantly agricultural country to one where industry and services play a larger role. This dissertation zeroes in on the water security of municipalities in the Philippines, which were sorted into different syndromes based on a combination of their risk to future hydro-climatic changes and economic growth trends. Four syndromes which covered 73% of the population then emerged. By comparing five case study municipalities drawn from these four syndromes, I offer insights into how different combinations of climatic and economic factors can impact water security, and which combination could have the lowest water security in the future. Through analyzing the results of focus group discussions and semi-structured interviews, I also explore the variation of perceptions and collaborative strategies of stakeholders regarding their current and future water security. While each municipality had different climate and economic vulnerabilities, they shared largely similar water security perceptions and used the same strategies.
ContributorsLorenzo, Theresa Marie (Author) / Kinzig, Ann (Thesis advisor) / David, Carlos Primo (Committee member) / Perrings, Charles (Committee member) / Schoon, Michael (Committee member) / Selin, Cynthia (Committee member) / Arizona State University (Publisher)
Created2021
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Description
Stressors to marine environments are predicted to increase and affect the well-being of marine ecosystems and coastal communities. Marine protected areas (MPAs) are one most widely implemented interventions for marine stressors. Despite the implementation of thousands of protected areas worldwide, people are still striving to understand their dynamics as they

Stressors to marine environments are predicted to increase and affect the well-being of marine ecosystems and coastal communities. Marine protected areas (MPAs) are one most widely implemented interventions for marine stressors. Despite the implementation of thousands of protected areas worldwide, people are still striving to understand their dynamics as they vary in their efficacy and many MPAs have not met their objectives. Additionally, those that have often fail to protect the ecosystem services and cultural values necessary for human community health. Thus, research has expanded to include analyses of the human and social dimensions that may limit their effectiveness. This dissertation explores the role of community engagement in marine protected areas and perceptions of environmental changes in coastal communities. Currently, existing research on the roles of community engagement in marine conservation interventions is limited, particularly in the island-states of the Caribbean region. This dissertation contains a review of the literature to understand the nuances of community engagement in relation to MPAs. Through the review, it was determined that primary forms of engagement are interviews and surveys, and respondents primarily included businesses, community members, fishers, and resource users. To better understand the perceptions and practices on-the-ground, key informants were interviewed across the Caribbean. There are strong desires to conduct community engagement for innumerable benefits, but there are barriers that some participants have overcome. Sharing information between MPA sites offers an opportunity to effectively engage community members. For the local case study, Charlotteville, Trinidad and Tobago, a small, coastal fishing town in the northeast region of Tobago was selected to understand the role of perceptions of environmental changes. There were strong ties of environmental and social changes, with an emphasis on the impacts of environmental stressors to human health. The heterogeneity and diversity of responses in this chapter highlight the need to consider who is engaged in community engagement activities.
ContributorsBernard, Miranda Lynn (Author) / Gerber, Leah (Thesis advisor) / Buzinde, Christine (Committee member) / Schoon, Michael (Committee member) / Kittinger, Jack (Committee member) / Cheng, Samantha (Committee member) / Arizona State University (Publisher)
Created2021
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Description

As part of an international collaboration to compare large-scale commons, we used the Social-Ecological Systems Meta-Analysis Database (SESMAD) to systematically map out attributes of and changes in the Great Barrier Reef Marine Park (GBRMP) in Australia. We focus on eight design principles from common-pool resource (CPR) theory and other key

As part of an international collaboration to compare large-scale commons, we used the Social-Ecological Systems Meta-Analysis Database (SESMAD) to systematically map out attributes of and changes in the Great Barrier Reef Marine Park (GBRMP) in Australia. We focus on eight design principles from common-pool resource (CPR) theory and other key social-ecological systems governance variables, and explore to what extent they help explain the social and ecological outcomes of park management through time. Our analysis showed that commercial fisheries management and the re-zoning of the GBRMP in 2004 led to improvements in ecological condition of the reef, particularly fisheries. These boundary and rights changes were supported by effective monitoring, sanctioning and conflict resolution. Moderate biophysical connectivity was also important for improved outcomes. However, our analysis also highlighted that continued challenges to improved ecological health in terms of coral cover and biodiversity can be explained by fuzzy boundaries between land and sea, and the significance of external drivers to even large-scale social-ecological systems (SES). While ecological and institutional fit in the marine SES was high, this was not the case when considering the coastal SES. Nested governance arrangements become even more important at this larger scale. To our knowledge, our paper provides the first analysis linking the re-zoning of the GBRMP to CPR and SES theory. We discuss important challenges to coding large-scale systems for meta-analysis.

Created2013-11-30
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Description

The Montreal Protocol is generally credited as a successful example of international cooperation in response to a global environmental problem. As a result, the production and consumption of ozone-depleting substances has declined rapidly, and it is expected that atmospheric ozone concentrations will return to their normal ranges toward the end

The Montreal Protocol is generally credited as a successful example of international cooperation in response to a global environmental problem. As a result, the production and consumption of ozone-depleting substances has declined rapidly, and it is expected that atmospheric ozone concentrations will return to their normal ranges toward the end of this century. This paper applies the social-ecological system framework and common-pool resource theory to explore the congruence between successful resolution of small-scale appropriation problems and ozone regulation, a large-scale pollution problem. The results of our analysis correspond closely to past studies of the Protocol that highlight the importance of attributes such as a limited number of major industrial producers, advances in scientific knowledge, and the availability of technological substitutes. However, in contrast to previous theoretical accounts that focus on one or a few variables, our analysis suggests that its success may have been the result of interactions between a wider range of SES attributes, many of which are associated with successful small-scale environmental governance. Although carefully noting the limitations of drawing conclusions from the analysis of a single case, our analysis reveals the potential for fruitful interplay between common-pool resource theory and large-scale pollution problems.

ContributorsEpstein, Graham (Author) / Perez Ibarra, Irene (Author) / Schoon, Michael (Author) / Meek, Chanda L. (Author) / College of Liberal Arts and Sciences (Contributor)
Created2013-11-30
Description

Background: Cancer diagnosis in both dogs and humans is complicated by the lack of a non-invasive diagnostic test. To meet this clinical need, we apply the recently developed immunosignature assay to spontaneous canine lymphoma as clinical proof-of-concept. Here we evaluate the immunosignature as a diagnostic for spontaneous canine lymphoma at both

Background: Cancer diagnosis in both dogs and humans is complicated by the lack of a non-invasive diagnostic test. To meet this clinical need, we apply the recently developed immunosignature assay to spontaneous canine lymphoma as clinical proof-of-concept. Here we evaluate the immunosignature as a diagnostic for spontaneous canine lymphoma at both at initial diagnosis and evaluating the disease free interval following treatment.

Methods: Sera from dogs with confirmed lymphoma (B cell n = 38, T cell n = 11) and clinically normal dogs (n = 39) were analyzed. Serum antibody responses were characterized by analyzing the binding pattern, or immunosignature, of serum antibodies on a non-natural sequence peptide microarray. Peptides were selected and tested for the ability to distinguish healthy dogs from those with lymphoma and to distinguish lymphoma subtypes based on immunophenotype. The immunosignature of dogs with lymphoma were evaluated for individual signatures. Changes in the immunosignatures were evaluated following treatment and eventual relapse.

Results: Despite being a clonal disease, both an individual immunosignature and a generalized lymphoma immunosignature were observed in each dog. The general lymphoma immunosignature identified in the initial set of dogs (n = 32) was able to predict disease status in an independent set of dogs (n = 42, 97% accuracy). A separate immunosignature was able to distinguish the lymphoma based on immunophenotype (n = 25, 88% accuracy). The individual immunosignature was capable of confirming remission three months following diagnosis. Immunosignature at diagnosis was able to predict which dogs with B cell lymphoma would relapse in less than 120 days (n = 33, 97% accuracy).

Conclusion: We conclude that the immunosignature can serve as a multilevel diagnostic for canine, and potentially human, lymphoma.

ContributorsJohnston, Stephen (Author) / Thamm, Douglas H. (Author) / Legutki, Joseph Barten (Author) / Biodesign Institute (Contributor)
Created2014-09-08