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- Creators: Arizona State University
However, since these classic vulnerabilities are known weaknesses, special types of protections have been added to the compilers which create the executable code and the systems that run them. The most common forms of protection include Address SpaceLayout Randomization (ASLR), Non-eXecutable stack (NX Stack), and stack cookies or canaries. Of course, these protections and their implementations vary depending on the system. I intend to look specifically at the Android operating system which is used in the daily lives of a significant portion of the planet. Most Android applications execute in a Java context and leave little room for exploitability, however, there are also many applications which utilize external libraries to handle more computationally intensive tasks.
The goal of this thesis is to take a closer look at such applications and the protections surrounding them, especially how the default system protections as mentioned above are implemented and applied to the vulnerable external libraries. However, this is only half of the problem. The attacker must get their payload inside of the application in the first place. Since it is necessary to understand how this is occurring, I will also be exploring how the Android operating system gives outside information to applications and how developers have chosen to use that information.
tissue growth, development, and repair. First isolated from neuronal tissues, much interest in this protein resides in development of the central nervous system and neuronal regeneration. Owning to its role in growth, development and its ability to promote angiogenesis and metastasis, PTN’s overexpression in cancers such as glioblastoma, has become the focal point of much research. Many of the receptors through which PTN acts contain glycosaminoglycans (GAGs), through which PTN binds. Thus, understanding the atomistic detail of PTN’s architecture and interaction with GAG chains is of significant importance in elucidating its functional role in growth and malignancy of biological tissues, as well as in neural development and progression of other diseases. Herein the first solution state structure of PTN was solved via nuclear magnetic resonance (NMR), with extensive characterization of its ability to bind GAG. Structurally, PTN consists of two -sheet domains connected by a short flexible linker, and flanked by long flexible termini. Broad distribution of positively charged amino acids in the protein’s sequence yields highly basic surfaces on the -sheet domains as well as highly cationic termini. With GAG chains themselves being linear anionic polymers, all interactions between these sugars and PTN are most exclusively driven through the electrostatic interactions between them, with no discernable specificity for GAG types. Moreover, this binding event is coordinated mostly through basic patches located in the C-Terminal domain (CTD). Although the flexible C- terminus has been shown to play a significant role in receptor binding, data here also reveal an adaptability of PTN to maintain high affinity interactions through its structured domains
when termini are removed. Additionally, analysis of binding information revealed for the first time the presence of a secondary GAG binding site within PTN. It is shown that PTN’s CTD constitutes the major binding site, while the N-terminal domain (NTD) contains the much weaker secondary site. Finally, compilation of high-resolution data containing the atomistic detail of PTN’s interaction with GAG provided the information necessary to produce the highest accuracy model to date of the PTN-GAG complex. Taken together, these findings provide means for specific targeting of this mitogenic cytokine in a wide array of biological applications.
on-indigenous healthcare workers and service providers, I explore the interrelationship of social perceptions of physical disability with understandings of identity and performance of personhood. Embedded within discourses and critiques of ableism/disablism, narratives highlight the interconnection of constructs of personhood and productivity.
Findings show that social perceptions of physical disability are closely linked to broader cultural norms surrounding concepts of health/illness. I offer a critical analysis of contemporary impacts of colonization and historical trauma on the physical, emotional, sociocultural and economic wellbeing of Diné people and those who fill service provision roles for this diverse population. Situated within broader contexts of defining constructs of ‘Whiteness’ and ‘Indigeneity’, the role of culture and discourses regarding stereotypes are particularly prominent factors in shaping relationships.
This interdisciplinary ethnography brings together contributions from Anthropology, Disability Studies, and Indigenous paradigms. Placing a particular emphasis on the social dynamics in two urban centers in the state of Arizona, this ethnography centers on analyzing areas of medical practice that work well, as well as gaps in the provision of healthcare services, with a particular focus on systemic and infrastructural barriers. These concerns are shared not only by Diné individuals with
physical disabilities and family members, but also by non-indigenous service providers and healthcare professionals.
An extensive effort was made to identify specific locations of crystal defects in epitaxial CdTe that might contribute to degraded light-conversion efficiency. Electroluminescence (EL) mapping and the creation of surface etch pits through chemical treatment were combined in attempts to identify specific structural defects for subsequent TEM examination. Observations of these specimens revealed only surface etch pits, without any visible indication of extended defects near their base. While chemical etch pits could be helpful for precisely locating extended defects that intersect with the treated surface, this study concluded that surface roughness surrounding etch pits would likely mitigate against their usefulness.
Defect locations in GaAs solar-cell devices were identified using combinations of EL, photoluminescence, and Raman scattering, and then studied more closely using TEM. Observations showed that device degradation was invariably associated with a cluster of extended defects, rather than a single defect, as previously assumed. AC-STEM observations revealed that individual defects within each cluster consisted primarily of intrinsic stacking faults terminated by 30° and 90° partial dislocations, although other defect structures were also identified. Lomer dislocations were identified near locations where two lines of strain contrast intersected in a large cluster, and a comparatively shallow cluster, largely constrained to the GaAs emitter layer, contained 60° perfect dislocations associated with localized strain contrast.
In another study, misfit dislocations at II-VI/III-V heterovalent interfaces were investigated and characterized using AC-STEM. Misfit strain at ZnTe/GaAs interfaces, which have relatively high lattice mismatch (7.38%), was relieved primarily through Lomer dislocations, while ZnTe/InP interfaces, with only 3.85% lattice mismatch, were relaxed by a mixture of 60° perfect dislocations, 30° partial dislocations, and Lomer dislocations. These results were consistent with the previous findings that misfit strain was relaxed primarily through 60° perfect dislocations that had either dissociated into partial dislocations or interacted to form Lomer dislocations as the amount of misfit strain increased.
In order to characterize the ankle mechanics and understand the underlying mechanisms that influence the neuromuscular properties of the ankle, a novel multi-axial robotic platform was developed. The robotic platform is capable of simulating various haptic environments and transiently perturbing the ankle to analyze the neuromechanics of the ankle, specifically the ankle impedance. Humans modulate ankle impedance to perform various tasks of the lower limb. The robotic platform is used to analyze the modulation of ankle impedance during postural balance and locomotion on various haptic environments. Further, various factors that influence modulation of ankle impedance were identified. Using the factors identified during environment dependent impedance modulation studies, the quantitative relationship between these factors, namely the muscle activation of major ankle muscles, the weight loading on ankle and the torque generation at the ankle was analyzed during postural balance and locomotion. A universal neuromuscular model of the ankle that quantitatively relates ankle stiffness, the major component of ankle impedance, to these factors was developed.
This neuromuscular model is then used as a basis to study the alterations caused in ankle behavior due to neurodegenerative disorders such as Multiple Sclerosis and Stroke. Pilot studies to validate the analysis of altered ankle behavior and demonstrate the effectiveness of robotic rehabilitation protocols in addressing the altered ankle behavior were performed. The pilot studies demonstrate that the altered ankle mechanics can be quantified in the affected populations and correlate with the observed adverse effects of the disability. Further, robotic rehabilitation protocols improve ankle control in affected populations as seen through functional improvements in postural balance and locomotion, validating the neuromuscular approach for rehabilitation.
Underground infrastructure is a critical part of the essential utility services provided to society and the backbone of modern civilization. However, now more than ever before, the disastrous events of a striking underground utilities cost billions of dollars each year in societal damages. Advanced technology and sophisticated visualization techniques such as augmented reality (AR) now play a significant role in mitigating such devastating consequences. Therefore, it is vitally important to coordinate resources, share information, and ensure efficient communication between construction personnel and utility owners. Besides, geographic information systems (GIS) provide a solution for interoperability in the construction industry. Applying such technologies in the field of underground construction requires accurate and up-to-date information. However, there is currently limited research that has integrated AR and GIS and evaluated the effectiveness and usability of the combination in this domain. The main objective of this research was to develop an integrated AR-GIS for mapping and capturing underground utilities using a mobile device. To achieve these objectives, a design research approach utilized to develop and evaluate a mobile extended-reality (XR-GIS) application. This research has produced an efficient solution for data collection and sharing among stakeholders in the underground construction industry. The main challenge in creating a reliable and adaptive outdoor AR system is the accurate registration of virtual objects in the real world. Due to the limited accuracy of smartphones, this study used an external Global Positioning System (GPS) devices to reduce positional error. The primary motivation behind this research is to make the construction industry more aware of the benefits of leveraging AR to prevent utility strikes and enhance public safety.
This dissertation fills the gap in the knowledge regarding applying Augmented Reality (AR) in the underground infrastructure mapping. This study’s three research objectives are:
(1) Identify the challenges and barriers facing the underground construction industry when applying AR.
(2) Develop an integrated AR-GIS for mapping and capturing underground utilities using a mobile device.
(3) Evaluate the horizontal accuracy of the captured data used by the AR phone application XR-GIS that has been developed by the author.
This dissertation examines the role of tribal sovereignty and self-determination in research for Diné participants and elders from 1956-1986. The qualitative historical research study explored the following questions: How has past research been conducted on the Navajo Nation? What is the role of sovereignty and self-determination in research and research methodology for Diné peoples? And, how might Diné philosophy inform a research methodology that aligns with cultural protocols and practices? Six elders who participated in research from 1956-1986 participated in in-depth interviews about their experiences. Using Sa’ąh Naaghái Bik’eh Hozhǫ̨̨́ǫ́n and related Diné philosophy models, findings of this study inform an Indigenous elder knowledge protection model (i.e. Nihookáá’ Diné Nidoolkah Bindii’ą’) to support existing Diné tribal IRB protocols and policies and provides additional insight for tribal cultural protection organizations. Lastly, the researcher presents a Diné intersectional methodology for future research.