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The nineteenth-century invention of smallpox vaccination in Great Britain has been well studied for its significance in the history of medicine as well as the ways in which it exposes Victorian anxieties regarding British nationalism, rural and urban class struggles, the behaviors of women, and animal contamination. Yet inoculation against

The nineteenth-century invention of smallpox vaccination in Great Britain has been well studied for its significance in the history of medicine as well as the ways in which it exposes Victorian anxieties regarding British nationalism, rural and urban class struggles, the behaviors of women, and animal contamination. Yet inoculation against smallpox by variolation, vaccination’s predecessor and a well-established Chinese medical technique that was spread from east to west to Great Britain, remains largely understudied in modern scholarly literature. In the early 1700s, Lady Mary Wortley Montagu, credited with bringing smallpox variolation to Great Britain, wrote first about the practice in the Turkish city of Adrianople and describes variolation as a “useful invention,” yet laments that, unlike the Turkish women who variolate only those in their “small neighborhoods,” British doctors would be able to “destroy this [disease] swiftly” worldwide should they adopt variolation. Examined through the lens of Edward Said’s Orientalism, techno-Orientalism, and medical Orientalism and contextualized by a comparison to British attitudes toward nineteenth century vaccination, eighteenth century smallpox variolation’s introduction to Britain from the non-British “Orient” represents an instance of reversed Orientalism, in which a technologically deficient British “Occident” must “Orientalize” itself to import the superior medical technology of variolation into Britain. In a scramble to retain technological superiority over the Chinese Orient, Britain manufactures a sense of total difference between an imagined British version of variolation and a real, non-British version of variolation. This imagination of total difference is maintained through characterizations of the non-British variolation as ancient, unsafe, and practiced by illegitimate practitioners, while the imagined British variolation is characterized as safe, heroic, and practiced by legitimate British medical doctors. The Occident’s instance of medical technological inferiority brought about by the importation of variolation from the Orient, which I propose represents an eighteenth-century instance of what I call medical techno-Orientalism, represents an expression of British anxiety over a medical technologically superior Orient—anxieties which express themselves as retaliatory attacks on the Orient and variolation as it is practiced in the Orient—and as an expression of British desire to maintain medical technological superiority over the Orient.

ContributorsMalotky, Braeden M (Author) / Agruss, David (Thesis director) / Soares, Rebecca (Committee member) / School of Life Sciences (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The goal of this project was to design and create a genetic construct that would allow for <br/>tumor growth to be induced in the center of the wing imaginal disc of Drosophila larvae, the <br/>R85E08 domain, using a heat shock. The resulting transgene would be combined with other <br/>transgenes in

The goal of this project was to design and create a genetic construct that would allow for <br/>tumor growth to be induced in the center of the wing imaginal disc of Drosophila larvae, the <br/>R85E08 domain, using a heat shock. The resulting transgene would be combined with other <br/>transgenes in a single fly that would allow for simultaneous expression of the oncogene and, in <br/>the surrounding cells, other genes of interest. This system would help establish Drosophila as a <br/>more versatile and reliable model organism for cancer research. Furthermore, pilot studies were <br/>performed, using elements of the final proposed system, to determine if tumor growth is possible <br/>in the center of the disc, which oncogene produces the best results, and if oncogene expression <br/>induced later in development causes tumor growth. Three different candidate genes were <br/>investigated: RasV12, PvrACT, and Avli.

ContributorsSt Peter, John Daniel (Author) / Harris, Rob (Thesis director) / Varsani, Arvind (Committee member) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Microfluidic devices represent a growing technology in the world of analytical chemistry. Serial femtosecond crystallography (SFX) utilizes microfluidic devices to generate droplets of an aqueous buffer containing protein crystals, which are then fired out as a jet in the beam of an X-ray free electron laser (XFEL). A crucial part

Microfluidic devices represent a growing technology in the world of analytical chemistry. Serial femtosecond crystallography (SFX) utilizes microfluidic devices to generate droplets of an aqueous buffer containing protein crystals, which are then fired out as a jet in the beam of an X-ray free electron laser (XFEL). A crucial part of the device is its method of droplet detection. This project presents a design for a capacitive sensor that uses a unique electrode configuration to detect the difference in capacitance between the aqueous and oil phases. This design was developed using MATLAB and COMSOL Multiphysics simulations and printed using high-resolution 3D printing. Results show that this design can successfully distinguish between the two immiscible liquids, confirming it as a possible detection method in future SFX experiments.

ContributorsCorder, Cameron Dean (Author) / Ros, Alexandra (Thesis director) / Williams, Peter (Committee member) / Hayes, Mark (Committee member) / School of Molecular Sciences (Contributor) / School of International Letters and Cultures (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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During the COVID-19 pandemic, increased burdens have been placed on the Arizona healthcare system, and its healthcare providers. Using a survey with a sample of N=308 prescribing providers and nurses in the Arizona healthcare system, the impact of COVID-19 on the wellbeing of healthcare providers was assessed. The survey used

During the COVID-19 pandemic, increased burdens have been placed on the Arizona healthcare system, and its healthcare providers. Using a survey with a sample of N=308 prescribing providers and nurses in the Arizona healthcare system, the impact of COVID-19 on the wellbeing of healthcare providers was assessed. The survey used measures to evaluate for physical and emotional wellbeing, burnout, stressors associated with COVID-19, and work-life experiences, and found an overall negative impact on the wellbeing of healthcare workers during the COVID-19 pandemic with increased levels of reported stress and tiredness, concern for the health of family and loved ones, concern for the hardships of patients, lack of alignment between organizational priorities and personal values, and low levels of support and appreciation from socially and from leadership at work.

ContributorsJohnson, Emma Carina (Author) / Schuster, Roseanne (Thesis director) / Michalec, Barret (Committee member) / School of Molecular Sciences (Contributor) / School of Human Evolution & Social Change (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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The colossal global counterfeit market and advances in cryptography including quantum computing supremacy have led the drive for a class of anti-counterfeit tags that are physically unclonable. Dendrites, previously considered an undesirable side effect of battery operation, have promise as an extremely versatile version of such tags, with their fundamental

The colossal global counterfeit market and advances in cryptography including quantum computing supremacy have led the drive for a class of anti-counterfeit tags that are physically unclonable. Dendrites, previously considered an undesirable side effect of battery operation, have promise as an extremely versatile version of such tags, with their fundamental nature ensuring that no two dendrites are alike and that they can be read at multiple magnification scales. In this work, we first pursue a simulation for electrochemical dendrites that elucidates fundamental information about their growth mechanism. We then translate these results into physical dendrites and demonstrate methods of producing a hash from these dendrites that is damage-tolerant for real-world verification. Finally, we explore theoretical curiosities that arise from the fractal nature of dendrites. We find that uniquely ramified dendrites, which rely on lower ion mobility and conductive deposition, are particularly amenable to wavelet hashing, and demonstrate that these dendrites have strong commercial potential for securing supply chains at the highest level while maintaining a low price point.

ContributorsSneh, Tal (Author) / Kozicki, Michael (Thesis director) / Gonzalez-Velo, Yago (Committee member) / School of Molecular Sciences (Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Fluoroquinolone antibiotics have been known to cause severe, multisystem adverse side effects, termed fluoroquinolone toxicity (FQT). This toxicity syndrome can present with adverse effects that vary from individual to individual, including effects on the musculoskeletal and nervous systems, among others. The mechanism behind FQT in mammals is not known, although

Fluoroquinolone antibiotics have been known to cause severe, multisystem adverse side effects, termed fluoroquinolone toxicity (FQT). This toxicity syndrome can present with adverse effects that vary from individual to individual, including effects on the musculoskeletal and nervous systems, among others. The mechanism behind FQT in mammals is not known, although various possibilities have been investigated. Among the hypothesized FQT mechanisms, those that could potentially explain multisystem toxicity include off-target mammalian topoisomerase interactions, increased production of reactive oxygen species, oxidative stress, and oxidative damage, as well as metal chelating properties of FQs. This review presents relevant information on fluoroquinolone antibiotics and FQT and explores the mechanisms that have been proposed. A fluoroquinolone-induced increase in reactive oxygen species and subsequent oxidative stress and damage presents the strongest evidence to explain this multisystem toxicity syndrome. Understanding the mechanism of FQT in mammals is important to aid in the prevention and treatment of this condition.

ContributorsHall, Brooke Ashlyn (Author) / Redding, Kevin (Thesis director) / Wideman, Jeremy (Committee member) / Borges, Chad (Committee member) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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A growing body of research suggests a link between adverse childhood experiences and negative health outcomes. However, less is known about where racial discrimination ranks compared to other adverse childhood experiences, such as maltreatment. To address this issue, I conducted two systematic reviews of meta-analyses to compare the magnitudes of

A growing body of research suggests a link between adverse childhood experiences and negative health outcomes. However, less is known about where racial discrimination ranks compared to other adverse childhood experiences, such as maltreatment. To address this issue, I conducted two systematic reviews of meta-analyses to compare the magnitudes of the links between racial discrimination and depressive symptoms and childhood maltreatment and depressive symptoms. My aim was to establish if racial discrimination should be considered an adverse childhood experience. My results demonstrated that the link between racial discrimination and depressive symptoms (r = 0.27) is comparable to the links between 4 different manifestations of maltreatment and depressive symptoms (physical abuse: r = 0.257, emotional abuse: r = 0.301, neglect: r = 0.381, sexual abuse: r = 0.408). I discuss the implications of these findings and propose future research directions.

ContributorsYoo, Joyce Eun-Young (Author) / Causadias, José (Thesis director) / Morris, Kamryn (Committee member) / School of International Letters and Cultures (Contributor) / School of Molecular Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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ABSTRACT Group III-nitride semiconductor materials have been commercially used in fabrication of light-emitting diodes (LEDs) and laser diodes (LDs) covering the spectral range from UV to visible and infrared, and exhibit unique properties suitable for modern optoelectronic applications. Great advances have recently happened in the research and development in high-power

ABSTRACT Group III-nitride semiconductor materials have been commercially used in fabrication of light-emitting diodes (LEDs) and laser diodes (LDs) covering the spectral range from UV to visible and infrared, and exhibit unique properties suitable for modern optoelectronic applications. Great advances have recently happened in the research and development in high-power and high-efficiency blue-green-white LEDs, blue LDs and other optoelectronic applications. However, there are still many unsolved challenges with these materials. In this dissertation, several issues concerning structural, electronic and optical properties of III-nitrides have been investigated using a combination of transmission electron microscopy (TEM), electron holography (EH) and cathodoluminescence (CL) techniques. First, a trend of indium chemical inhomogeneity has been found as the indium composition increases for the InGaN epitaxial layers grown by hydride vapor phase epitaxy. Second, different mechanisms contributing to the strain relaxation have been studied for non-polar InGaN epitaxial layers grown on zinc oxide (ZnO) substrate. Third, various structural morphologies of non-polar InGaN epitaxial layers grown on free-standing GaN substrate have been investigated. Fourth, the effect of the growth temperature on the performance of GaN lattice-matched InAlN electron blocking layers has been studied. Finally, the electronic and optical properties of GaN nanowires containing a AlN/GaN superlattice structure have been investigated showing relatively small internal electric field and superlattice- and defect-related emissions along the nanowires.
ContributorsSun, Kewei (Author) / Ponce, Fernando (Thesis advisor) / Smith, David (Committee member) / Treacy, Michael (Committee member) / Drucker, Jeffery (Committee member) / Schmidt, Kevin (Committee member) / Arizona State University (Publisher)
Created2011
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In this dissertation, remote plasma interactions with the surfaces of low-k interlayer dielectric (ILD), Cu and Cu adhesion layers are investigated. The first part of the study focuses on the simultaneous plasma treatment of ILD and chemical mechanical polishing (CMP) Cu surfaces using N2/H2 plasma processes. H atoms and radicals

In this dissertation, remote plasma interactions with the surfaces of low-k interlayer dielectric (ILD), Cu and Cu adhesion layers are investigated. The first part of the study focuses on the simultaneous plasma treatment of ILD and chemical mechanical polishing (CMP) Cu surfaces using N2/H2 plasma processes. H atoms and radicals in the plasma react with the carbon groups leading to carbon removal for the ILD films. Results indicate that an N2 plasma forms an amide-like layer on the surface which apparently leads to reduced carbon abstraction from an H2 plasma process. In addition, FTIR spectra indicate the formation of hydroxyl (Si-OH) groups following the plasma exposure. Increased temperature (380 °C) processing leads to a reduction of the hydroxyl group formation compared to ambient temperature processes, resulting in reduced changes of the dielectric constant. For CMP Cu surfaces, the carbonate contamination was removed by an H2 plasma process at elevated temperature while the C-C and C-H contamination was removed by an N2 plasma process at elevated temperature. The second part of this study examined oxide stability and cleaning of Ru surfaces as well as consequent Cu film thermal stability with the Ru layers. The ~2 monolayer native Ru oxide was reduced after H-plasma processing. The thermal stability or islanding of the Cu film on the Ru substrate was characterized by in-situ XPS. After plasma cleaning of the Ru adhesion layer, the deposited Cu exhibited full coverage. In contrast, for Cu deposition on the Ru native oxide substrate, Cu islanding was detected and was described in terms of grain boundary grooving and surface and interface energies. The thermal stability of 7 nm Ti, Pt and Ru ii interfacial adhesion layers between a Cu film (10 nm) and a Ta barrier layer (4 nm) have been investigated in the third part. The barrier properties and interfacial stability have been evaluated by Rutherford backscattering spectrometry (RBS). Atomic force microscopy (AFM) was used to measure the surfaces before and after annealing, and all the surfaces are relatively smooth excluding islanding or de-wetting phenomena as a cause of the instability. The RBS showed no discernible diffusion across the adhesion layer/Ta and Ta/Si interfaces which provides a stable underlying layer. For a Ti interfacial layer RBS indicates that during 400 °C annealing Ti interdiffuses through the Cu film and accumulates at the surface. For the Pt/Cu system Pt interdiffuion is detected which is less evident than Ti. Among the three adhesion layer candidates, Ru shows negligible diffusion into the Cu film indicating thermal stability at 400 °C.
ContributorsLiu, Xin (Author) / Nemanich, Robert (Thesis advisor) / Chamberlin, Ralph (Committee member) / Chen, Tingyong (Committee member) / Smith, David (Committee member) / Ponce, Fernando (Committee member) / Arizona State University (Publisher)
Created2012
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The energy band gap of a semiconductor material critically influences the operating wavelength of an optoelectronic device. Realization of any desired band gap, or even spatially graded band gaps, is important for applications such as lasers, light-emitting diodes (LEDs), solar cells, and detectors. Compared to thin films, nanowires offer greater

The energy band gap of a semiconductor material critically influences the operating wavelength of an optoelectronic device. Realization of any desired band gap, or even spatially graded band gaps, is important for applications such as lasers, light-emitting diodes (LEDs), solar cells, and detectors. Compared to thin films, nanowires offer greater flexibility for achieving a variety of alloy compositions. Furthermore, the nanowire geometry permits simultaneous incorporation of a wide range of compositions on a single substrate. Such controllable alloy composition variation can be realized either within an individual nanowire or between distinct nanowires across a substrate. This dissertation explores the control of spatial composition variation in ternary alloy nanowires. Nanowires were grown by the vapor-liquid-solid (VLS) mechanism using chemical vapor deposition (CVD). The gas-phase supersaturation was considered in order to optimize the deposition morphology. Composition and structure were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive x-ray spectroscopy (EDS), and x-ray diffraction (XRD). Optical properties were investigated through photoluminescence (PL) measurements. The chalcogenides selected as alloy endpoints were lead sulfide (PbS), cadmium sulfide (CdS), and cadmium selenide (CdSe). Three growth modes of PbS were identified, which included contributions from spontaneously generated catalyst. The resulting wires were found capable of lasing with wavelengths over 4000 nm, representing the longest known wavelength from a sub-wavelength wire. For CdxPb1-xS nanowires, it was established that the cooling process significantly affects the alloy composition and structure. Quenching was critical to retain metastable alloys with x up to 0.14, representing a new composition in nanowire form. Alternatively, gradual cooling caused phase segregation, which created heterostructures with light emission in both the visible and mid-infrared regimes. The CdSSe alloy system was fully explored for spatial composition variation. CdSxSe1-x nanowires were grown with composition variation across the substrate. Subsequent contact printing preserved the designed composition gradient and led to the demonstration of a variable wavelength photodetector device. CdSSe axial heterostructure nanowires were also achieved. The growth process involved many variables, including a deliberate and controllable change in substrate temperature. As a result, both red and green light emission was detected from single nanowires.
ContributorsNichols, Patricia (Author) / Ning, Cun-Zheng (Thesis advisor) / Carpenter, Ray (Committee member) / Bennett, Peter (Committee member) / Smith, David (Committee member) / Arizona State University (Publisher)
Created2012