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Amazon’s Ring: How Smart Home Cameras Produce a Consumer Policing Model
No full textGovernment, police and businesses deploy fear and terror to control the narrative surrounding the
politics of surveillance and increase their power over individuals’ everyday lives. As with
Foucault’s panopticon, in modern day surveillance, people are often unaware that they are being
watched, or if they are aware, they comply for the betterment of the community. Companies like
Amazon push the boundaries of acceptable surveillance methods with home cameras under the
guise of “keeping people safe,” and adopt new biometric technologies that their law enforcement
partners use against local communities as seen in Dallas/Fort Worth. According to David Lyon,
the new surveillance is “individualized and competitive” (Lyon 60). We must not forget the
active role of the subject regarding surveillance and its aggressive technologies. As subjects in a
rapidly advancing technological world, it is vital that we should learn to return the gaze and
counteract abusive surveillance methods like the Ring
A Chemical Toolbox for Stimuli-responsive Photoresins in 3D Printing
No full textThree-dimensional printing (3DP) is an advanced manufacturing process that builds successive
layers of materials to create objects from digital models. Without the need of molds, 3DP enables
the rapid fabrication of complex and customizable products at low cost. Several 3DP techniques
are available, being extrusion and vat photopolymerization some of the most used. Compared to
extrusion, vat photopolymerization techniques stand out due to their efficiency in fabricating
objects with minimal mechanical anisotropy and high resolution. These techniques are based on
the spatiotemporal control of a polymerization reaction using light to build the polymer layers.
However, most resins that are compatible with this manufacturing process are based on
conventional acrylate monomers and have limited functionality.
Inspired by the ability of natural systems to adapt to external conditions, several developments in
polymer science have endowed polymers with the intrinsic ability to modify their properties under
external stimuli, but it remains a challenge to incorporate this functionality into conventional 3D
printable polymers. The objective of this research is to develop a chemical toolbox that expands
the availability of stimuli-responsive photoprintable materials with improved processability and
functionality.
The first chapter provides a review of approaches in incorporating chemical interactions to
improve the processability and functionality of 3D printable materials, including noncovalent
interactions, dynamic covalent chemistry and click chemistry, and how this toolbox enables
stimuli-responsive properties, such as self-healing.
The second chapter describes the development of photoprintable polymer networks that include
furan-maleimide Diels-Alder thermally reversible cycloadducts to enable self-healing in 3D
printed objects, with up to a 99% self-healing efficiency, as observed in the recovery of mechanical
strength, without affecting their detailed printed shape.
The third chapter describes the use of ureas as pendant hydrogen bonding groups to provide
noncovalent crosslinking, to enable fine tuning in the mechanical properties, and to endow the
printed parts with self-healing properties.
The fourth chapter describes the use of click and unclick reactions to facilitate the control in the
integrity of a 3D printable polymer network, by photoprinting at 405 nm via thiol-ene, but enabling
degradation at 365 nm via cleavage of ortho-nitrobenzyl ester.
This research demonstrates the potential of using a chemical toolbox to develop advanced
functionality in 3D photoprintable materials an enable delicate control of their properties
Investigating the Roles of Verification and Enhancement in Partner Personality Perception on Romantic Relationship Outcomes
No full textThere is debate within the close relationships literature on whether possessing more verifying or
more enhancing views of one’s partner is more beneficial for romantic relationship outcomes.
Verification theories suggest that relationships benefit when romantic partners hold congruent
views of each other; in contrast, enhancement theories hold that it is more beneficial that partners
see each other in a positive light, regardless of their strengths and weaknesses. Empirical
research has provided mixed evidence for both theories, which may suggest that a combination
of verification and enhancement contributes most fully to positive romantic relationship
outcomes. Therefore, this research aimed to investigate how verifying and enhanced views of
romantic partners’ personality traits across the dimensions of Positive Emotionality, Negative
Emotionality, and Constraint may interact in their associations with the relationship outcomes of
intimacy and conflict. The participant sample (475 mixed-sex dating and married couples) was
taken from six waves of archival data collected as part of the Family Transitions Project. Truth
and Bias model analyses were used to determine whether participants displayed verification (in
the form of tracking accuracy) and enhancement (in the form of positivity bias) in judgments of
their partners’ personality traits over time. Participants did display verification in their
perceptions of their partners’ traits over the study period, but there was not sufficient evidence of
enhanced perceptions of partner personality traits. Truth and Bias model analyses specified with
multilevel structural equation modeling were used to determine whether greater verification of
partner personality traits is associated with more positive romantic relationship outcomes.
Verification was not found to be associated with intimacy, conflict, or relationship satisfaction.
Dyadic response surface analyses were performed to determine whether greater enhancement of
partner personality traits is associated with more positive romantic relationship outcomes.
Contrary to hypotheses, greater enhancement of partners’ positive personality traits was
associated with less intimacy in women and lower relationship quality in men. Further, greater
enhancement of partners’ negative personality traits was associated with less intimacy in men.
The findings for conflict were mixed: Men reported lower levels of conflict the more they
enhanced their partners' negative traits, but reported higher levels of conflict the more their
partners enhanced their negative traits. Moderated dyadic response surface analyses were
performed to determine whether verification and enhancement interact in their association with
romantic relationship outcomes. There was not sufficient evidence to suggest that there is an
interaction effect between verification and enhancement on either intimacy or conflict. Overall,
the current research provides a novel longitudinal approach to the investigation of verification
and enhancement in partner personality perception and suggests that further research is needed to
more fully explore how verification and enhancement motivations influence relationship
dynamics over time
Modern Iranian Fiction in the United States: Translation, Publication, and Promotion (1979–2022)
No full textMy dissertation investigates the translation of modern Iranian writers in the United States. My
particular focus is on the fictional works that have been written after the Iranian revolution in
1979. I examine what writers and what works have been translated and what is the place of
these writers in the post-revolutionary literary landscape of Iran. I also examine the reception of
this translated literature among the American readership through the analysis of the critical
reviews in journals and magazines. In addition, I specifically explore the process of
transmission and promotion of these literary works through an overview of the translators and
the publishers who were involved. I investigate the criteria and motivations of these translators
through a study of their educational and professional backgrounds as well as their knowledge of
Persian and English. I also study the type of publishers and their editorial and publicity
approaches that have played a significant role in the presentation of this literature in the United
States. Additionally, I argue about the critical role of the Iranian-American community as well
as academia in presenting and promoting this literature in the US. The findings of this research
show that the representation of Iranian literature in the United States is an outcome of political,
cultural, and economic factors. Based on the results of this study, I argue that although this
literature is not under-represented in the American literary translation market, it has remained
somehow invisible due to the stereotypical images of media about Iran, the financial challenges
of the writers, translators, and publishers, and also the cultural and linguistic differences.
However, the constant process of transmitting this literature has never been stopped thanks to
the contributions of the Iranian-American community. This research has succeeded in drawing a
clear picture of the challenges for the representation and promotion of the translated literature of
a minor language in the American literary market
A Steep-slope Threshold Switching Selector Using Silver-doped Polycrystalline Zinc Oxide: Fabrication, Characterization, & Application for 3D X-point Memory & Neuromorphic Devices
No full textAn assortment of emerging non-volatile memory (NVM) devices has displayed a surge of interest
in being investigated for their implementation in energy-efficient bio-inspired neuromorphic
computing. The intrinsic device physics of NVMs give them the capability to be employed for
emulating the dynamics of a biological neuron and synapse. NVM devices are connected in a dense
cross (X)-point circuit architecture thus enabling massive system-level parallelism necessary for a
neural network. However, the leakage/sneak current that typically arises from neighboring
unselected memory cells is considered as a stumbling block in enlarging X-point arrays. Metalfilament threshold switch has been suggested as a selector device, demonstrated on low leakage
characteristics, that holds potentiality due to its straightforward metal-insulator-metal structure,
superior performance, and excellent CMOS process compatibility.
This dissertation demonstrates research study on the electrical and surface characterization of
nano-polycrystalline silver-doped zinc oxide (ZnO) thin films for threshold switching selector
device, to propose a way for amending the prevalent selector drawbacks: threshold voltage (Vth) variabilities i.e., intercell and cycle-to-cycle shifts and lousy DC cycling endurance. The current
work demonstrates a novel approach to subside system variabilities by uniformly doping a
crystalline selector medium i.e., ZnO with Ag metal atoms, rather than incorporating an Ag active
metal layer/electrode.
First, electrochemical deposition (ECD) process has been employed to slightly dope ZnO with Ag,
because of its admirable dopant concentration controllability having atomic percent precision.
ECD process helps in demonstrating the proof-of-concept experiment and provides an
understanding of volatile switching behavior when ZnO is lightly doped with Ag. Next, “supercycle ALD” technique has been evaluated, where alternating ZnO ALD and Ag metal ALD was
employed for lightly doping/delta doping ZnO with Ag.
To fend off the shortcomings/drawbacks associated with both the ECD and ALD processes, RF
magnetron co-sputtering process is the last fabrication method put to evaluation. Co-sputtering
technique provides the wherewithal to control Ag doping levels when lightly doped composite
targets (ZnO/Ag 100-x/x at. %, x=1,3,10) are employed. The switching parameters were observed
to significantly improve and the trends have been explained based on surface characterizations
with XPS, GIXRD, AFM, SEM, EDAX, ICP-MS, HR-TEM, and semiconductor parameter
analyzer
Barriers to Industrial Development in Sub-Saharan Africa
No full textThis study examines the barriers hindering the adoption of Flying Geese Paradigm in sub-
Saharan Africa. The study examined these constraints within the context of how the factor inputs
proposed by Alfred Marshall (land, labor, capital and enterprise) have evolved in sub-Saharan
Africa. The results indicate a generally negative effect of natural resource rents on manufacturing
in most sub-Saharan African countries, challenging the adoption of the Flying Geese Paradigm,
except for a few countries. This observation suggests the existence of specific circumstances
under which natural resource rents could have a favorable impact on the growth of
manufacturing. The study also found that domestic credit to the private sector by banks has a
positive impact on manufacturing, but this influence diminishes with a year lag. Foreign direct
investment does not have a statistically significant effect on manufacturing in the region. On
enterprise, the study found the presence of indigenous manufacturing enterprises, indicative of
the region's potential to develop local manufacturing activities. Despite their presence,
unaddressed challenges, such as limited access to credit, intense competition with foreign
investments, and labor shortages, may impede their capacity to contribute to manufacturing
growth in Sub-Saharan Africa. Regarding labor cost, the predicted average labor cost per worker
in sub-Saharan African countries is higher than in comparator countries in Asia but lower than in
Central/South America. The study findings also show that among countries with lower GDP per
capita, sub-Saharan African countries have a labor cost advantage over their counterparts.
However, in the middle-high GDP per capita category, sub-Saharan African countries maintain a
slightly higher predicted labor cost compared to comparator countries
Microfluidic Platform for Analyzing Chemotaxis of Bone Marrow Derived Murine Neutrophils Towards S. Aureus
No full textWith the rise of MRSA (Methicillin-Resistant Staphylococcus aureus), there is a need for
investigating alternatives to traditional antibiotics. A growing alternative exists in the form of
chemoattraction based therapeutics which enhance the immune system’s response to infection.
Novel methodologies will need to be developed to measure the increased activity. Our
microfluidic system was used to show that the introduction of chemoattractants increased
neutrophil migration towards Staphylococcus aureus, pointing to potential utility in therapy.
Traditional migration assays, such as Boyden chambers are not ideal for measuring chemotaxis
from mouse cells as they require a large number of cells (>100,000 per condition), make it
difficult to pay discern the movements of individual cells, and cannot be used to measure
directionality or retrotaxis. Mature neutrophils, band cells, and other cells from the marrow
microenvironment were harvested from murine bone marrow and placed in a microfluidic chip in
order to measure and quantify their migration patterns. We establish a baseline reaction of
migration towards media populated by S. aureus and chemoattractants separately. Then we
combined both stimuli to demonstrate how chemoattractants improved immune response and to
confirm that this migration rate was four times higher than what neutrophils would respond
without the aid of additional stimuli. Experiments found that the average quantity of neutrophils
migrating increases when chemoattractants are added to media where S. aureus was present in
comparison to media where S. aureus was injected without any chemoattractants. These results
confirmed that chemoattractants improved cell migration, offering a potential mechanism for
treatment of disease, and showed how our platform was capable of quantifying migrations
towards pathogens
Analytical and Empirical Analyses of Treatment Optimization and Sequential Bargaining: Applications to Opioid Prescriptions and Real Estate Markets
No full textAnalytic approaches towards individual decision-making construct a significant portion
of the operations management literature. Following its weight in our profession, my doc-
toral studies are built upon decision-making problems surrounding two major contexts;
opioid prescriptions for pain management in healthcare and price negotiations in real es-
tate markets. These studies collaborated with co-authors are presented in this dissertation
over three separate chapters.
Clinical decisions for opioid prescribing are critical since the prescribing too little can
cause patients to suffer from pain whereas prescribing too much may lead to serious
drawbacks such as dependence, addition, overdose, and even death. A chapter in this dis-
sertation is reserved for a published manuscript collaborated with co-authors, in which,
mental trade-offs of clinicians for opioid prescribing decisions are captured in an analyt-
ical pain framework. The framework is flexible to capture both acute and chronic pain
cases, and yields a minimization objective in terms of opioid prescription duration com-
bining the total pain, total discomfort from adverse effects, and the risk of drug inefficacy
due to tolerance or increased sensitivity to pain. Despite non-convexity of the objective,
a closed-form optimal prescription amount is found. Analyses over the optimal solution
show that the role of adverse effects in prescribing decisions is as critical as that of the
pain level. Interestingly, we find that the optimal prescription duration is not necessarily
increasing with the recovery time. We show that not incorporating the risk of tolerance /
increased sensitivity leads to overprescribing. Clinicians’ beliefs on this risk can be cur-
tailed at patient handovers, thus leading to overprescribing. We also show overprescrib-
ing can be mitigated by adaptive treatments. Lastly, using real-life pain and opioid use
data from two sources, we estimate the timing of tolerance / increased pain sensitivity
and discuss the proximity of our model to clinical practice. This paper has a pain man-
agement framework that leads to tractable models. These models can potentially support
balanced opioid prescribing after their validation in a clinical setting. Then, they can
be helpful to policymakers in assessment of prescription policies and of the controversy
around over(under)prescribing.
The other two chapters of the dissertation are reserved for my doctoral studies on price
negotiations in real estate markets, both of which are collaborated with co-authors. The
mainstream adoption of online marketplaces allows large-scale collection of structured
back-and-forth (sequential) bargaining data. Obtaining such data from an online real-
estate marketplace company, we empirically analyze sequential price bargains for houses
between the company (institutional seller) and individual buyers. In each bargain, par-
ties (the seller and buyer) take turns to make concessions until one of them terminates the
bargain by accepting the other’s offer or by exiting. Our analyses of concessions and ter-
minations respectively yield that parties make diminishing and absolutist (independent
of current counteroffer) concessions, whereas they make relativist terminations. These
results are robust when tested separately for different buyer and house types, except that
certain buyer types make absolutist terminations. We explain relativist (resp. absolutist)
acceptances via high (resp. low) sensitivity to the looming deal price, and relativist (resp.
absolutist) exits by scarcity (resp. multitude) of available alternatives. Moreover, we ana-
lytically show that the empirical properties of concessions apply for compromises as well.
These properties of compromises allow us to connect a party’s offers to her reservation
price via a simple offer curve. Randomizing offers around the curves, we obtain max-
imum likelihood estimates of reservation prices and bargaining powers in terms of the
buyer and house types. Providing offer, reservation price, and bargaining power estima-
tions, offer curves could lead to a decision support tool for bargaining decisions
Room-temperature Solid-state Synthesis, Characterization, and Properties of Halide Perovskite Materials
No full textHalide perovskite materials have unique optical and electrical properties, making them ideal
candidates for various applications, including photovoltaics, optoelectronics, solar cells, and
radiation detectors. However, their practical application faces challenges associated with
traditional solution-based synthesis, including complex purification, scalability issues, and long-
term instability.
A promising alternative to traditional solution-based synthesis is the use of room-temperature
solid-state methods, which offer, among others, a solvent-free, energy-efficient, and simple
synthesis approach. Nonetheless, a comprehensive understanding of the solid-state reaction
mechanisms is needed.
This thesis investigates the mechanisms of room-temperature solid-state reactions in halide
perovskite synthesis, including diverse halide perovskite compounds such as CsPbBr3, MAPBBr3,
CsCdBr3, and CsPbCl3. Advanced characterization techniques are used to gain deeper insights into
the reaction mechanisms. A better understanding of the mechanism will enable the stabilization of
complex compounds such as CsPbI3 and chlorine halide perovskites through a simple, one-step
synthesis process. This process facilitates synthesis and significantly improves the stability,
effectively addressing a crucial obstacle to their practical implementation.
Furthermore, this thesis extends beyond chemical synthesis and explores the fabrication of halide
perovskite films, which are crucial for optoelectronic applications, and introduces efficient
techniques for producing micron-thick perovskite films using closed-space sublimation methods.
These methods have proven effective in maintaining the intrinsic properties of the synthesized
perovskites while simplifying the film production process
Multiplexed Comprehensive Design and Characterization of an Electrochemical Interface Accessing Non-invasive Bodily Fluids Towards Quality-of-life Monitoring
No full textThe research presented in this thesis outlines the design and development of novel biosensing
platforms for monitoring biomarkers by the non-invasive sampling of body fluids with emphasis
on self-health and disease management. The purpose of this work is to demonstrate the efficacy of
two combinatorial biosensors – Continuous awareness through sweat platform (CLASP) and
Exhaled breath condensate scanning using rapid electro analytics (EBC-SURE) for the detection
of metabolic and inflammatory biomarkers towards integration onto low-power internet of things
(IoT) platforms for wearable and point-of-care diagnostic applications. First, this work
demonstrated the technical utility of a lancet-free, label-free platform for the combinatorial, and
continuous monitoring of alcohol and glucose in perspired human sweat produced without external
sweat induction strategies. The motivation of this study was to develop a sweat-based wearable
platform for alcohol and glucose management to monitor glucose levels on moderate consumption
of alcohol of diabetic social drinkers. A nanotextured sensor stack was embedded into a flexible
nanoporous substrate to achieve sensitive and specific affinity-based biomarker detection within
physiologically relevant ranges in ultralow volumes of sweat. Non-faradaic EIS is employed as
the signal transduction mechanism for biomarker detection to give an insight into the binding
events occurring at the sensor interface. Additionally, the CLASP platform was benchmarked
against commercially available hand-held devices to establish a one-to-one performance
correlation. Furthermore, this platform was employed to demonstrate the epidermal functionality
and sensor performance of CLASP for the on-body detection of sweat lactate to monitor restricted
oxygen supply in sedentary populations. The successful implementation of CLASP in detecting
metabolic biomarkers for health monitoring led to the transition of assessing the performance
metrics of this platform for the detection of inflammatory biomarkers such as cortisol and TNF-α
for chronic disease monitoring. The important highlight of this work was to establish the longterm temporal stability of the CLASP in detecting a simulated rise and fall in cortisol levels over
a 6-hour sleep cycle. The last effort was focused on developing a point-of-care aid platform- EBCSURE for the trace detection of inflammatory biomarkers in exhaled breath condensate for
monitoring respiratory disorders. Exhaled breath condensate is considered a promising source of
inflammatory biomarkers that can determine the pathophysiological processes underlying lung
inflammation in a simple and non-invasive manner. EBC-SURE displayed a stable performance
after rigorous testing enabling its integration onto diagnostic platforms for rapid quantification of
biomarkers related to a healthy and acute inflammatory disease condition