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WARNING: THIS PRODUCT IS TOO GOOD TO RESIST. EXAMINING THE INFLUENCE OF WARNING LABELS AND SOCIAL MEDIA CONTENT ABOUT NICOTINE ADDICTION ON INTENTIONS TO USE E-CIGARETTES AMONG YOUNG ADULTS IN THE U.S.
Get PDFThis dissertation reports on findings from two cross sectional surveys of U.S. young adults to experimentally test 1) the effects of e-cigarette warning labels about mental health consequences of nicotine addiction, compared to FDA’s current required message and a no-message control condition, on young adults’ intentions to use or quit e-cigarettes, beliefs about nicotine addiction, and perceived message effectiveness (PME); 2) the immediate effects of exposure to user-generated social media posts about nicotine addiction, by valence of content (i.e., positive or negative), versus control content unrelated to nicotine addiction, on beliefs about nicotine, subjective norms about nicotine, and intentions to use or quit e-cigarettes; and 3) the immediate effects of user-generated social media content exposure, by valence of content (i.e., positive or negative), versus control content unrelated to nicotine addiction, on PME of the current nicotine addiction warning label.
I found that, while brief exposure to warning label messages may not significantly impact intentions to use or quit e-cigarettes and beliefs about nicotine addiction, messages that nicotine addiction can worsen symptoms of depression and anxiety and that nicotine addiction is a source of stress had higher perceived effectiveness among young adults than FDA’s current message. Additionally, noncommercial social media content that shows nicotine addiction in a favorable light is associated with greater intentions to use e-cigarettes among young adults; content of different valences has differential impacts on some measures of beliefs and subjective norms. Finally, brief exposure to e-cigarette content on social media may not be a significant factor impacting the perceived effectiveness of warning label messages.
This dissertation underscores the need for e-cigarette warning labels focused on topics other than nicotine’s addictiveness. Furthermore, findings align add to a growing body of literature suggesting that noncommercial social media content about e-cigarettes influences behavioral intentions, beliefs, attitudes, and/or use of e-cigarettes among young people
‘Decreasing the Distance’ in the Climate Finance Gap: A Multicriteria Analysis of Policy Options to Generate Carbon Revenues from the International Aviation Sector
Get PDFA significant climate finance gap exists in the shortfall between the climate finance mobilized every year and the climate finance needed, which is estimated to increase to the trillions of dollars over the next few decades. Mobilizing these trillions will require scaling-up existing sources of finance while also raising new, innovative, and additional sources.
The international aviation sector offers an interesting opportunity to consider a novel way in which a hard-to-abate industry can generate billions of dollars in carbon revenues every year, without any market distorting effects, to be channeled as a source of climate finance. This creates the possibility of a new climate regime for the international aviation sector that would require the adoption of a policy at the global level.
Three potential policy options include: a passenger tax, a jet fuel tax, and an aircraft movement tax, but which of these policies is viable for adoption is the central question of this study. To be viable, such a policy should (i) gain the support of major powers, (ii) be politically feasible, (iii) be able to generate adequate (i.e., substantial) revenues, (iv) be easily implementable, and (v) not create market distortions.
A multicriteria analysis was undertaken to assess the policy options and found that a passenger tax would be the most viable for adoption among the three options. A jet fuel tax and aircraft movement tax remain possible alternatives but would pose more challenges to international adoption
DATA PRIVACY IN THE FIRE SERVICE: UNDERSTANDING THE POLICY ENVIRONMENT, FIREFIGHTER PREFERENCES, AND LEADERSHIP PERSPECTIVES
Get PDFObjective: Firefighters experience high rates of occupational injury and fatality while serving their communities. Despite growing interest in using health and safety data to understand and prevent injuries, little is known about the policies governing such data or firefighter or leadership perspectives on data privacy. This dissertation unpacks the policies governing firefighter occupational health and safety data in Maryland and Virginia and fire service stakeholders’ views towards current and future data practices.
Methods: Manuscript One leveraged legal research methods to identify and analyze federal, Maryland, and Virginia laws and regulations, and local union contracts. Manuscripts Two and Three used interviews and focus groups to assess the views of firefighters and fire department leaders in Maryland and Virginia, as well as national-level leaders.
Results: There were few laws and regulations directly related to occupational health and safety data privacy; of the 20 laws and regulations we identified, federal policies were most comprehensive in addressing data privacy. 11 union contracts varied significantly, with some limiting data access and others authorizing surveillance. 65 participants across 35 interviews and 4 focus groups described similar current data collection practices. Firefighters had few concerns about current practices while leaders described privacy concerns and resource challenges. Participants called for improved infrastructure, communication, and more mental health and exposure data. Firefighters were resistant to using biometric data from wearable devices on calls, citing autonomy and privacy concerns, whereas leadership supported this use case. Participants described barriers to implementation and conditions for acceptable wearable use, including limiting use cases and data access, sharing individual data with firefighters, and communicating the purpose and benefits to firefighters.
Conclusions: Data and wearable technology have the potential to contribute to firefighter health and safety but must be utilized in a way that protects firefighter autonomy and privacy. Unions could play a key role in negotiating for data privacy protections. Government officials and fire departments can help ensure ethical use of firefighter data by integrating privacy protections into data infrastructure and wearable interventions. Future research should fill data gaps and foster trust in data by communicating research results back to firefighters
INVESTIGATING THE ASSOCIATIONS BETWEEN RESPIRATORY FUNCTION AND WEARABLE ACCELEROMETRY MEASURES WITH COGNITION IN OLDER ADULTS
Get PDFBackground: As the global population ages, the prevalence of Alzheimer’s disease and related dementias (ADRD) are projected to nearly triple in the next 30 years. Given the scarcity of well-established and treatments for ADRD, efforts to prevent or delay ADRD are critical. Respiratory function is one potential modifiable ADRD risk factor; however, current data are mainly cross-sectional. Physical activity is another modifiable ADRD risk factor. Novel, objective measures of physical activity, such activity variability, may be more sensitive predictors of ADRD compared to traditional activity metrics.
Methods: Aim 1 used linear mixed-effects models to estimate PEF slopes for each participant and discrete-time proportional hazards models to assess associations between PEF slopes and dementia risk in the National Health and Aging Trends Study (NHATS). Aim 2 examined spirometry data (forced expiratory volume [FEV1] and forced vital capacity [FVC]) in the Cardiovascular Health Study and evaluated risk for incident dementia subtypes using Cox proportional hazards models. Aim 3 used cross-sectional NHATS data, and explored whether a novel metric of activity variability was associated with prevalent cognitive impairment using logistic regression and receiver operating characteristic curves.
Results: Rapid PEF declines were associated with greater dementia risk compared to those with no PEF changes (HR=1.84; 95% CI [1.23, 2.75]). Lower FVC z-scores were associated with higher all-cause dementia risk (HR=1.15; 95% CI [1.03, 1.28]) and vascular dementia risk (HR=1.35; 95% CI [1.00, 1.84]). Low activity variability was associated with higher odds of prevalent cognitive impairment (OR=2.23; 95% CI [1.26, 3.97] per SD decrease). Activity variability outperformed other established activity metrics in predicting prevalent cognitive impairment.
Conclusions: Poor respiratory function measured via a handheld flow meter and a clinical spirometer were associated with increased incident dementia risk. Respiratory function may contribute to dementia risk via the cardiorespiratory system. Participants with cognitive impairment may struggle with complex movements and engage in a limited variety of activities, potentially explaining lower activity variability. Taken together, these findings suggest that 1) greater consideration should be given to respiratory function as an ADRD risk factor and 2) activity variability may be a valuable metric to assess risk of cognitive impairment
DYNAMICS OF DNA DAMAGE
No full textReversible covalent chemistry is ubiquitous in nature, and chemists use the dynamics of reversible covalent chemistry for various purposes including drug design. Certain types of DNA damage also exhibit this chemistry, and hence are dynamic. As DNA damage causes genetic alterations and can lead to cell death, it is important to study the dynamic nature of these types of DNA damage to understand how it affects the severity of the harm.
The first part of this dissertation explores the role of reversible covalent chemistry in accumulation of DNA damage induced by UV irradiation. Cyclobutane pyrimidine dimers (CPDs) are the main cause of mutations induced by UV irradiation. The distribution of CPD is dependent on sequence and conformation of the DNA. While previous studies focused on CPD formation to elucidate what influences CPD distribution, the role of CPD reversion remained unexplored, despite the reversibility of CPDs under the conditions used to analyze its distribution. The goal is to examine the significance of CPD reversion. My data demonstrates that the CPD reversion occurs on the same timescale as CPD formation as highlighted through the dynamic response of CPDs to changes in DNA conformation. Hence, CPD reversion is significant and competes with CPD formation to control the CPD accumulation.
The second part of my dissertation describes the design of a reversible DNA crosslinker using quinone methides (QM) that can form dynamic crosslink and migrate along DNA. This migration may allow the crosslinker to evade cell repair processes and may potentially enhance its potency as a chemotherapeutic agent. The initial design in the Rokita research group comprised of bifunctional QM precursor (bisQMP) derivatives conjugated with acridine (Acr), a DNA intercalator (bisQMP-Acr). These compounds crosslinked DNA and the crosslinks migrated over 10 base pairs in 7 days which is too slow to compete with repair processes. Subsequent attempts using polyammonium ions conjugated to a bisQMP for binding to DNA through electrostatic interactions resulted in irreversible adducts with the DNA. In this work, bisQMP was conjugated to 1,8-naphthalimide (bisQMP-Naph) which is known to intercalate into DNA from the major grove and is a weak intercalator compared to Acr which could allow faster migration. Two derivatives of bisQMP-Naph with ester (bisQMP-NaphO) and amide (bisQMP-NaphN) linkers were designed. Interestingly, only the bisQMP-NaphN crosslinked DNA. Moreover, bisQMP-NaphN is selective for adjacent GC rich sequences and B form of duplexes. Then, to potentially enhance the QM dynamics, an electron rich analogue of bisQMP-NaphN was designed by substituting the methylene group adjacent to the bisQMP with an ether linkage. However, no dynamic crosslinking was observed.
This work highlights the significance of reversible covalent chemistry in accumulation of CPD and the role of the linker and intercalator in designing a DNA crosslinker to affect DNA’s crosslinking, its dynamics as well as selectivity towards DNA duplexes
LEVERAGING ANALYTICAL METHODS TO ELUCIDATE THE ENVIRONMENTAL FATE OF PLASTICS AND THEIR CHEMICAL ADDITIVES
No full textOver time discarded plastics are degraded by chemical and physical processes, resulting in the leaching of chemical additives and the release of vast numbers of microplastics into the environment. Despite the ever-growing production of single-use plastics, minimal attention is given to understanding the factors that govern these processes or their potential risks to the environment. To address these knowledge gaps, a multi-part strategy is described herein that utilizes multiple analytical techniques to investigate both additive release and transformation, as well as the environmental degradation of plastics into microplastics.
In Chapter I, we examine the release behavior of several benzophenone-type chemical additives from model polystyrene composites in the presence of sunlight and UV-irradiation. Liquid chromatography high resolution-mass spectrometry (LC-HRMS) was demonstrated capable of detecting low concentrations (µg L-1) of leached benzophenones without additional extraction. Direct photolysis studies of benzophenones in solution facilitated identification of multiple transient photoproducts. Accelerated weathering experiments highlighted the complex nature of release and subsequent additive phototransformation when examining accumulation of additives.
In Chapter II, we review the analytical challenges in quantifying microplastics in environmental matrices and examine current approaches to investigating microplastic behavior. We then present a novel fabrication method to prepare environmentally-realistic, metal-tagged micro- and nanoplastics for a range of commercially relevant polymers. Single particle inductively coupled plasma mass spectrometry (spICP-MS) is shown capable of measuring these polydisperse particles in heterogeneous matrices at low concentrations. We further demonstrate the application of these metal-tagged nanoplastics in several laboratory-based studies.
In Chapter III, we utilize a photoinactive flame retardant to investigate the role of irradiative conditioning on additive release and identified a dependence of setting (wet or dry) on additive leaching. This enabled assessment of additive release in which a plastic material is first exposed to sunlight in a dry condition (i.e. land or roadside) followed by aqueous submersion (incorporation in a water system). Liquid chromatography coupled with high resolution mass spectrometry (LC-HRMS) was used to quantify the concentration of released additives to part-per-billion concentrations. Furthermore, we utilized the method described in Chapter II to investigate the formation of nanoplastics during the lifecycle of a plastic material
Characterizing the Remodeling of the Lamina Cribrosa of Glaucoma Eyes
Get PDFGlaucoma is the leading cause of irreversible vision loss and affects roughly 80 million people worldwide. Glaucoma is characterized by progressive visual field loss from the death of retinal ganglion cell axons in the optic nerve head (ONH). The primary site of axonal dysfunction in glaucoma is the lamina cribrosa (LC), the part of the eye wall in the ONH. The human LC is formed from cribriform plates composed of elastin, collagen types I and III, and various proteoglycans. When viewed en face, the plates resemble a beam and pore network that supports axons exiting the eye. A major risk factor of glaucoma is excessive intraocular pressure (IOP). High IOP mechanically deforms the LC, and those deformations stretch, compress, and shear axons. Over time, the LC remodels and the plate-like structure thins and becomes more curved with progressive axonal damage. The collagen, elastin, and proteoglycan composition also change, and the pores become smaller. These changes in microstructure and tissue composition may influence the biomechanics of the LC. LC biomechanics have previously been measured using various optical imaging methods and digital volume correlation (DVC) both ex vivo and in vivo for short term IOP change. However, the LC deformations from long term remodeling have not been studied. The strain and remodeling may be biomarkers for the susceptibility of patients to glaucoma damage or worsening of vision loss following medical intervention. Therefore, the objective of this work was to characterize the long-term remodeling of the LC of glaucoma eyes by measuring LC biomechanics and structure.
The first part of this work characterized remodeling of the LC of postmortem human donor eyes and compare to the degree of axonal damage. The second study estimates the direct strain response to IOP change in vivo in glaucoma patients and their relationship to clinical measurements of glaucoma damage. The final study reimages the glaucoma subjects of the second study years later to estimate the remodeling deformations in the LC following medical intervention
DEVELOPING COLLABORATIVE PROCESSES FOR ACCURATE ESTIMATION OF SCOPE 3 EMISSIONS: A CASE STUDY OF SOUTHERN CALIFORNIA EDISON AND ITS CONSTRUCTION VENDORS
Get PDFCalifornia’s goal of decarbonizing the power grid requires improved methods to quantify greenhouse gas (GHG) emissions, particularly Scope 3 - supply chain emissions, which fall outside direct operational control. While Southern California Edison (SCE) has adopted spend-based approaches in line with global GHG accounting standards, there is growing pressure to enhance their accuracy, driven by upcoming state regulations mandating GHG disclosure by 2027.
Outsourced construction services are a key focus for improving SCE’s Scope 3 emissions reporting. As the company accelerates infrastructure upgrades to meet carbon neutrality goals, the associated carbon footprint risks offsetting GHG reductions from clean energy initiatives, potentially undermining SCE’s broader decarbonization achievements.
This capstone provides a foundational assessment of the benefits and challenges of adopting a collaborative, hybrid process for estimating GHG emissions from outsourced substation construction services. Through quantitative and qualitative analyses, it compares spend-based and hybrid methodologies and proposes a collaborative reporting framework involving SCE and its vendors.
The findings offer valuable insights into designing scalable emissions reporting processes applicable across the utility industry.
This research paper is organized into six sections: I) Executive Summary, II) Introduction and Literature Review, III) Methods, IV) Results, V) Discussion, and VI) Acknowledgements
DEVELOPMENT OF SENSORS BASED ON ORGANIC FIELD EFFECT TRANSISTORS AND ORGANIC ELECTROCHEMICAL TRANSISTORS
No full textThis dissertation summarizes the biosensing work based on the organic electrochemical transistors (OECT) platform, and particulates sensing work based on the organic field effect transistors (OFET) platform. Both platforms consist of three terminals: source, drain, and gate. The organic semiconductors (OSCs) will cover the channel region between source and drain. The advantage of using OSC layers is that the functional groups in the OSC layers can make them bioreceptor layers or sensing layers as well as the semiconductor layers at the same time. For OECT-based biosensors, the bioreceptors were first immobilized on the channel region, and polythiophene backboned polymers covered the channel region. In this setup, the interaction between myelin basic protein (MBP) and MBP antibody, and receptor binding domain (RBD) of SARS-Cov-2 virus and Spike 1 protein antibody were detected. The experiments from these experiments also proved that polythiophene backbone with carboxylic acid groups or hydroxyl groups in their side chains can be semiconducting layers as well as bioreceptor layers. To improve the behavior of the biosensors, the bioreceptors were then immobilized on the gate electrode. New circuit designs were also developed to decrease the drift in the control experiments, in order to increase the sensitivity and to lower the limit of detection. Single gate sensing configuration includes one OECT device while dual gate sensing configuration includes two OECT devices. For single gate sensing configuration, the voltage only applies in one direction, while for dual gate sensing configuration, the voltage application is in opposite directions in the two OECT devices. The design of the dual gate sensing configuration proves that this setup can largely cancel the drift from ions accumulation.
The particulate sensors were developed on the OFETs platform. The advantage of the OFETs platform is that by using OSC layers with different backbones and functional groups, particulates can have different interactions with the OSC layers. The results can prove that particles with different functional groups will have different effects on the OSC layers, which can be reflected through the current change
THE DEAD I’VE KNOWN: A MEMOIR OF HOSPICE NURSING
No full textIn 2014, I began a career as a home hospice nurse. I had been trying, without success, to get pregnant for a few years by then, and I became convinced that these two things—my proximity to the dead and my inability to conceive—were connected. It seemed that the reasons for my failure weren’t simply biological, but supernatural. The Dead I’ve Known is my memoir of undergoing treatment for infertility while working as a hospice nurse, and the ways in which our beliefs about life, death, love and worth shape one another, and ourselves