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The Impact of Accelerated Digitization on Patient Portal Use by Underprivileged Racial Minority Groups During COVID-19: Longitudinal Study
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Background
Prior research on the digital divide has documented substantial racial inequality in using web-based health resources. The recent COVID-19 pandemic led to accelerated mass digitization, raising alarms that underprivileged racial minority groups are left further behind. However, it is unclear to what extent the use of health information and communications technology by underprivileged racial minority groups is affected.
Objective
We have considered the COVID-19 disruption as a rare exogenous shock and estimated the impact of the accelerated digitization on the quantity and variety of patient portal use. In this study, we aimed to answer the following 2 key research questions. Did patients alter their use of health information and communications technology owing to COVID-19–induced digital acceleration? Does the effect differ across racial lines?
Methods
We used a longitudinal patient portal use data set gathered from a large urban academic medical center to explore the effect of accelerated digitization on the racial digital gap in health care. We limited the sample period of our study to 2 same periods (March 11 to August 30) in 2019 and 2020. Our final sample consisted of 25,612 patients belonging to 1 of the 3 racial groups: Black or African American (n=5157, 20.13%), Hispanic (n=253, 0.99%), and White (n=20,202, 78.88%) patients. We estimated the panel data regression using 3 different models: pooled ordinary least squares (OLS), random effect (RE), and fixed effect (FE).
Results
Our study yielded 4 findings. First, we confirmed that the racial digital divide remains a significant issue for telehealth; underprivileged racial minority group patients had lower patient portal use than White patients before the pandemic (Minority: OLS, β=−.158; P<.001; RE, β=−.168; P<.001). Second, we found that the digital gap regarding patient portal use frequency between underprivileged racial minority groups and White patients is shrinking rather than widening after the COVID-19 pandemic started (COVID_Period×Minority: OLS, β=.028; P=.002; RE, β=.037; P<.001; FE, β=.043; P<.001). Third, the shrinking gap is foremost driven by access through mobile (vs desktop) devices (COVID_Period×Minority: web, β=−.020; P=.02; mobile, β=.037; P<.001). Finally, underprivileged racial minority groups expanded their use of a variety of portal functionalities faster than White patients during the pandemic (COVID_Period×Minority [for functionality]: OLS, β=−.004; P<.001; RE, β=−.004; P<.001; FE, β=−.003; P=.001).
Conclusions
Using the COVID-19 pandemic as a natural experiment, we offer empirical evidence that accelerated digitization has shrunk the racial digital divide in telehealth, and the trend is mostly driven by mobile devices. These findings provide new insights into the digital behaviors among underprivileged racial minority groups during accelerated digitization. They also offer policy makers an opportunity to identify new strategies to help close the racial digital gap in the postpandemic world.
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Search for the Chiral Magnetic Effect in Au+Au collisions at sNN‾‾‾√=27 GeV with the STAR forward Event Plane Detectors
No full textApplications of Tunnel Oxides in Selective Contact and Schottky Barrier-Based Photovoltaics
No full textNovel photovoltaic (PV) cell designs intended to replace p-n junctions are a subject of constant research in the push for more cost-effective solar power. Many of these new technologies benefit from the incorporation of tunnel insulators, which are deposited at the semiconductor interface but remain thin enough for quantum tunneling of charge carriers to occur. Atomic layer deposition (ALD) is a technique utilizing self-limiting chemical half reactions to deposit films with angstrom-level thickness control and is thus an ideal method for fabricating and studying tunnel oxides.PVs utilizing carrier-selective contacts (CSCs) add external layers to PV absorbers. These layers extract one type of charge carrier, either electrons or holes, from the absorber while blocking the other. Defect states may facilitate electron-hole recombination at the interface between the absorber and the CSC, hence tunnel oxides are often introduced at these interfaces to passivate the defects. Data presented in Chapter 3 of the present work have shown that ultrathin aluminum oxide can reduce recombination at the interface between p-type Si and hole-selective molybdenum oxide contacts, reducing surface recombination velocity (SRV) from >1,000 to ~200 cm·s-1 depending on substrate termination, interlayer thickness, and annealing parameters. The study in Chapter 4 examined electron-selective titanium oxide and showed that even without AlOx, interfacial chemical silicon oxide with proper thermal treatment reached SRV values as low as 40 cm·s-1 at the Si/TiOx interface. As-deposited samples incorporating AlOx at the interface exhibited SRV as low as 20 cm·s-1, however passivation degraded with annealing on these samples, and none of the AlOx samples achieved ohmic n-Si/TiOx contacts, suggesting a barrier to carrier collection. Metal-insulator-semiconductor (MIS) PVs instead utilize the Schottky barrier characteristic of metal-semiconductor contacts, relying on a large barrier height (?B) to separate charge carriers. Inserting tunnel oxides at the MS interface is known to affect ?B for several possible reasons, including the formation of dipoles at the interface between two dissimilar oxides. The study in Chapter 5 has investigated these different hypotheses by systematically studying the effects of inserting different high-? tunnel oxides into a n-Si/SiOx/Ni diode stack. ?B increases as large as 0.37 eV and decreases as large as 0.19 eV relative to a SiOx-only insulator were observed, depending on the high-? oxide added. The data correlated with the differences in the oxygen areal density (OAD) between the high-? oxides and SiOx. A relatively unexplored concept is the modulation of ?B using stacks of dissimilar high-? tunnel oxides. The experiments reported in Chapter 6 fabricated AlOx/LaOx tunnel stacks, hypothesizing that the large OAD difference between the two high-? oxides would induce a large dipole and ?B change. When LaOx was introduced, ?B changes relative to an AlOx-only insulator did occur but appeared to be the result of competing interactions between each high-? oxide with the substrate, rather than the high-?/high-? interface. Finally, Chapter 7 reports tunnel stacks of AlOx with a wider variety of other high-? oxides in both deposition orders (AlOx deposited before or after the other oxide). SiOx/high-? interfaces were considered in attempt to isolate the effects of the high-?/high-? interfaces. Apparent dipole strengths of up to 0.40 eV were attributed to the high-?/high-? interface, with the modulation of ?B loosely associated with the differences in both parent metal electronegativity and OAD between the stacked oxides. The larger the EN or OAD difference, the larger the change in ?B, with exceptions
Proteolyzed Vascular Extracellular Matrix-Coated Substrates As An In Vitro Model To Assess Aneurysmal Smooth Muscle Cell Behavior
No full textAbdominal aortic aneurysms (AAAs) are localized expansions of the abdominal aortic wall that gradually increase in size until potential vessel wall ruptures, which is highly fatal. AAAs are a multifactorial disease involving the chronic overexpression of proteolytic enzymes and inflammatory factors in the aorta wall post endothelial layer injury. This causes naturally irreversible degradation and loss of the structural extracellular matrix (ECM) which in turn weakens the vessel wall. The current treatment method for this disease is surveillance via ultrasound until aneurysms reach a critical size for rupture, thus mandating risky open or endovascular surgery. There is thus a critical need to develop non-surgical treatments to slow or reverse the development of AAA noninvasively. In drug discovery and development, in vitro trials are a necessary first step in achieving clinical use of a therapeutic. Before a drug can be use in vivo, its safety, efficacy, and cytotoxicity must be examined and found acceptable. In the case of AAA, novel therapeutics are tested on cultured vascular smooth muscle cells (VSMCs), the primary cell effected in this disease. Unfortunately, VSMCs have been shown to dedifferentiated and behave more similarly to fibroblasts than smooth muscle cells when cultured in vitro on plain tissue culture plastic, making results from in vitro experiments less accurate when translating to in vivo testing. The purpose of this study is to generate an in vitro surface coating using ECM from carefully digested abdominal aortic wall tissue to induce VSMCs to maintain their diseased phenotype. To do this, the tunica media, or the vessel wall layer in which VSMCs reside, was isolated from the whole aorta and subsequently decellularized and partially digested with elastase and collagenase. This generated a cell-free tissue containing elastin peptides as well as many native ECM components. After solubilizing the derived ECM powder, an ECM surface coating was adsorbed to tissue culture plastic at a rate of 0.61+/- 0.12 µg/cm2. The digested ECM surface coating had characteristics more similar to tropoelastin than collagen, but was not identical to either. When passage 7 (P7) rat elastase induced-aneurysmal aortic smooth muscle cells (EaRASMCs) were cultured on the ECM coating, they exhibited a more spindle-shaped morphology than EaRASMCs cultured on uncoated plastic. Culturing P7 EaRASMCs on the ECM coated substrate more closely evoked gene expression trends indicative of the inflammatory and immune cell-infiltrated AAA microenvironment versus P7 EaRASMCs cultured on tissue culture plastic. P7 EaRASMCs cultured on the ECM surface coating also produced more chemoattractant and inflammatory cytokines in relation to P7 EaRASMCs cultured on plain tissue culture plastic. This study showed the capability to generate an in vitro cell culture substrate coating from native ECM and the ECM coating\u27s ability to modulate VSMC behavior in vitro. This in vitro culture model will be useful to screen aneurysmal VSMC responses to provided therapeutics including those that target enhanced ECM regeneration and repair in vitro in a manner that would be closely evocative of outcomes that could be expected in vivo
Early Detection of Oxidative Degradation in Styrene Butadiene-Based Pressure Sensitive Adhesive Blends Using Indirect Characterization Methods
No full textEarly detection of oxidative degradation in a styrene butadiene-based pressure sensitive adhesive is characterized using rapid, indirect, physical and mechanical characterization methods including color spectroscopy, dynamic thermal mechanical analysis and indentation techniques. The mechanical and physical characteristics are correlated to the changes in molecular weight, chemical structure and loss of performance. The molecular weight changes of chemical degradation are monitored by gel permeation chromatography (GPC) and the chemical changes by attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR). The verification in loss of adhesive performance is characterized by shear testing. An additive that behaves as a prooxidant, a source for free radicals, is blended into the pressure sensitive adhesive (PSA) to induce degradation. The PSAs were aged at ambient conditions (approximately 25C) or with slight heat (48.9C) in an air circulating oven to accelerate the degradation process. The samples were aged and characterized throughout a four-week period. Within the first week of accelerated aging, the unstabilized, heated conditioned adhesive showed a decrease in styrene butadiene molecular weight, confirming degradation had started. The colorimetry and shear modulus, at 150C, had no initial induction period for the degrading adhesive sample, immediately showing significant property changes. The tan delta peak, correlating to the midblock and endblock of the styrene butadiene elastomer, shifted in temperature and height throughout the aging period. Compression stress relaxation showed significant relaxation changes after the first week of heat aging. The stabilized control and comparative sample did not show changes in the measured properties throughout the testing period. Near the end of the four-week aging period, the unstabilized, ambiently aged comparative sample, started to show characteristic signs of the early stages of degradation
Uncovering the Selective Vulnerability of Dopaminergic Neurons
No full textParkinson\u27s Disease (PD) is the second most prevalent neurodegenerative disease and the most prevalent movement disorder. PD is characterized by the loss of dopaminergic (DA) neurons that occurs during aging. DA neurons affected by PD are located in the substantia nigra (SN) found in the central nervous system (CNS). This degeneration does not induce muscular deficits, but inhibits the hierarchical processing of movement that occurs within the CNS. The symptoms that arise with PD consist of but are not limited to tremors, bradykinesia, impaired gait and overall confusion that can be accompanied with memory loss. Studies have shown that the onset of PD occurs during late adulthood affecting mainly elderly people. Normally by then the disease has significantly progressed and the degeneration of DA neurons has already started. There is currently no cure available and with an aging population the need to find a cure has become even more crucial. Research presented in this dissertation evaluates the genetic mechanisms and factors associated with the maintenance of DA neurons. We evaluate these mechanisms by using known PD models and Drosophila melanogaster. We aim to provide further insight into the mechanism by which DA neurons are lost using the central hypothesis that genetic and environmental factors render specific neurons vulnerable while others remain resistant. The rationale behind our hypothesis comes from the residual unknown factors associated with the degeneration of specific DA neurons during aging. We found certain individual DA neurons that are either vulnerable or resistant to models of PD such as ? synuclein, Pink1B9 and rotenone. We use the model system, Drosophila melanogaster, as an efficient tool in order to investigate our hypothesis\u27. This dissertation also presents findings regarding the results of an unbiased genome-wide associated screen, which identified novel candidate genes involved in the maintenance of DA neurons. This screen was followed by further characterization of a previously unidentified gene involved in DA neuron longevity during aging. Understanding which genes are responsible for DA neuron protection, as well as identifying the factors that render specific DA neurons lost to PD, may uncover potential targets for future medicinal therapies
An Examination of School Bus Transportation Policy as it Relates to Student Attendance and Achievement
No full textSchool district provided transportation is one way to support student attendance and achievement. By removing the obstacle of getting to school, school districts provide the opportunity for students to learn in school. In a secondary database analysis of 2018-2019 data, this study triangulates student achievement, attendance, and transportation to quantify the implications of state and local transportation policy and to study avoidable absences that lead to low student performance.When comparing students who did and did not receive the offer of transportation, descriptive statistics revealed significant differences for the categories of race identification, meal status, and school. A student offered transportation was present an additional 6.138 days of school in a typical school year, and the offer of transportation was associated with an increase of a student\u27s grade point average (GPA) by 0.177 GPA points. Using a hierarchical multiple linear regression model to examine the offer of transportation and how it is associated with student attendance rate and noncumulative GPA for 9th and 10th grade students, this study estimated that the offer of transportation results in 4.801 percentage point greater attendance rate for a student who receives the offer of transportation and live at 2.0 miles. Additionally, the study identified centered distance, transportation status, the interaction of centered distance and transportation, free and reduced meal status, and marginalized students of color as significant predictors of attendance rate; and meal status, marginalized students of color, gender, and grade level were significant predictors of noncumulative GPA. By estimating the role of transportation to mitigate absences, this study was able to make the policy recommendation to improve student attendance in order to support student achievement
Rotation Periods of Slowly Rotating Asteroids with KELT Photometry
No full textThe study of asteroids is fascinating as they are remnants from the formation ofthe solar system. Their rotational properties can give us deeper insight into their other characteristics, such as their shape and internal structure, and the dynamical properties of the asteroid population as a whole can trace the evolution of the asteroid belt, and thus the solar system. As of now, most studies on asteroid rotation focus on faster rotators (approximately P < 24 h), as those are easier to measure with a small number of observations, but this has created a statistical bias against the detection of slower rotators. Our work focuses on asteroids with a rotational period greater than 24 h, and we use images from the Kilodegree Extremely Little Telescope (KELT), a ground-based wide-eld photometric survey originally designed to detect transiting planets. We have built a fully automated pipeline to process KELT images for the purpose of extracting asteroid lightcurves, and we have used a training sample of asteroids with known rotational periods to create a model that allows us to estimate the statistical reliability of results for a population of asteroids with unknown rotation periods. We report individual rotational periods for asteroids with a previously unknown periods, and for asteroids with known but uncertain periods. We also report rotation statistics on the brighter end of said population, which is in agreement with the notion of a statistical bias against the detection of slower rotators and thus hints at the necessity of further studies on the matter of slow rotators
Optical cooling and trapping of Lithium-6 atoms
No full textAn ultra-cold Fermi gas is a great way to simulate quantum many-body physics. The deeperunderstanding of strongly interacting fermionic systems gained from studying physics of such ultra-cold systems have found applications to high TC superconductors. The apparatus described here aims to study non-equilibrium dynamics and transport properties of unitary Fermi systems by optical cooling and trapping a cloud of 6Li atoms. My contribution to the design and construction of the Sommer group ultra-cold 6Li apparatus involves the design and construction of the Feshbach resonance electronics, AOM electronics for the laser system, setup of some of the AOM and ODT optics, and some coding. In this text I describe the design of our vacuum apparatus and laser system that traps and cools 6Li atoms to micro Kelvin temperatures, characterizes its performance, and describe how it can be utilized for spin transport experiments across normal-superfluid interfac