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Changing Marriage Dynamics in the United States, 1990s to 2010s
No full textIn this dissertation, I conduct three studies examining how evolving gender norms, economic factors, and other structural forces shaped marriage dynamics among different-sex couples in the United States between the 1990s and the 2010s, each involving analysis of data from the U.S. Current Population Survey. In the first study, I examine the rising proportion of sole-breadwinner married couples in the U.S., analyzing changes in the predictors of such arrangements to better understand the structural forces that might push couples toward a single-earner setup even as individuals increasingly express egalitarian gender ideals. I find that male-sole-breadwinner arrangements have become particularly more likely among couples with young children or multiple children; that men who work in professional or managerial occupations or regularly work 50 or more hours per week have been increasingly likely to serve as sole breadwinners; and that sole-breadwinner couples, whether the sole earner is female or male, have become increasingly economically disadvantaged over time. I conclude that rising childcare costs and evolving professional and managerial work norms may play significant roles in the rise of sole-breadwinner arrangements. In the second study, I examine changes over time in the couple-level economic predictors of cohabitation-to-marriage transitions in the U.S. I find that, between 1996 and 2020, couples in which the man served as the primary breadwinner became less likely to marry relative to couples with a more equal division of earnings or a female-breadwinner setup, and that women’s personal earnings became a more important predictor of marriage over time. I also find these changes to be driven primarily by college-educated couples. Finally, in the third study, I examine trends in internal migration among married couples, assessing whether migration decisions --- historically biased in favor of men's careers -- have become more gender-neutral over time. I find that that co-breadwinner married couples -- those in which both partners have similar incomes -- have become less likely to move long distances over time relative to other couples, which I argue indicates couples have become less likely to uproot women's careers for the benefit of men's. I also find that post-migration income and employment outcomes have become more gender-neutral over time, with women more likely to remain employed after long-distance moves among more highly educated couples and the income gap between spouses less likely to widen after moves among less-educated couples. I conclude with a discussion of implications regarding the relationships between marriage, gender inequality, and broader social inequality
Rural Energy Transition for Cooking in India—Revisiting the Drivers
No full textThe recent analysis from IEA (International Energy Agency) on energy transition in India highlights that cooking continues to be the weakest link in the energy transition process for rural households and that rural energy transition of households to cleaner fuel is nonlinear in nature. Several programs have been designed to plague the voids and address this nonlinearity, but the transition to cleaner alternatives for cooking did not happen in the pace it should ideally have. Therefore, an empirical exercise was carried out at a national level to revisit the disconnect between the income growth and energy transition and identify the drivers of the energy transition process in cooking at the national as well as at the subnational state level for a developing country. The paper adds to the current scholarship on drivers of household energy transition by analyzing the relationship between household energy choices and non-income determinants and proves the nonlinearity in energy consumption of rural households of Bihar. Analyzing unit level record from National Sample Survey, an empirical exercise was carried out by using multinomial logit model to identify the potential determining factors at the individual household and group level. The group effect analysis through fixed and random effect has been conducted purposely to understand if social and cultural norms or community level factors within a village society have any effect on the cooking energy transition of rural households and if that offsets the effect of household income in energy transition for cooking. Furthermore, to statistically examine the perceived non-linearity in the consumption of cooking fuel such as firewood by rural households, Brock–Dechert–Scheinkman (BDS) test was conducted for rural households of 38 districts of Bihar. The analysis helps in inferring that subsidy on modern fuel and/or other cooking alternatives alone may not suffice to drive the transition process, but more targeted intervention rooted in the local cultural context in consonance with social and cultural norms or community level factors could be more effective for sustained rural energy transition
Memes & Relational Communication: The Use of Idiomatic Utterances with Interpersonal Media
No full textThis dissertation used two studies to explore how memes are used interpersonally and how interpersonal media functions in partner’s relational communication. Study One used dyadic data from 81 same-sex friendships to illustrate how characteristics of the relationship (i.e., shared reality, closeness, responsiveness) can associate with perceiving idiomatic utterances like memes as relationally pertinent. Study Two used experience sampling data (n = 744) from 54 individuals to determine how the use of memes in daily mediated communication could positively associate with feeling connected and satisfied from mediated messages. Additionally, Study Two tested how the five functions of interpersonal media could also relate to perceptions of connection and communication satisfaction. These studies were meant to illustrate the bidirectionality of interpersonal media where the relationship may inform communication and messages shared can reinforce the bond of a relationship. The results of both studies are supportive of this bidirectionality. Specifically, the results from Study One suggest that close and responsive friends consider memes to be relationally pertinent in their ongoing relational communication. Findings from Study Two indicate that using memes and the five functions of interpersonal media can associate with feeling connected and satisfied with communication. However, moderation results indicate a negative interaction effect between certain functions and the presence of memes on connection and communication satisfaction. This dissertation offers useful evidence to continue building interpersonal research on memes
SHAKE TABLE TESTS TO COMPARE THE SEISMIC RESPONSE OF CONCRETE FRAMES WITH CONVENTIONAL AND HIGH-STRENGTH REINFORCEMENT
No full textReported test results suggest reinforcement grade can have an important effect on the seismic displacement demands of reinforced concrete (RC) structures. Two one-story one-bay RC frames (Specimens C1 and H1) were mounted in parallel on the NCREE-Taiwan shake table and simultaneously subjected to 16 base motions, each representing a horizontal component of recorded earthquakes. The dynamic tests were followed by quasi-static large-amplitude cyclic testing. The specimens had the same nominal dimensions and base shear strengths with longitudinal reinforcement that was Grade 60 (60 ksi [420 MPa]) in C1 and Grade 100 (100 ksi [690 MPa]) in H1. Maximum drifts of H1 were 1.3 to 2.3 times larger than for C1. The lateral stiffness of H1 was consistently lower than C1, with stiffness ratios (H1 to C1) ranging from 0.78 after Run 1 to 0.45 after Run 16. Drift estimates using stiffness values based on gross-section properties provided a reasonable upper bound for C1 but were unconservative for H1. Drift estimates based on the secant-to-yield stiffnesses, which were inversely proportional to reinforcement grade, provided an upper bound for both specimens. Preliminary recommendations are made for accounting for these effects in design
Microfluidic/HPLC combination to study carnosine protective activity on challenged human microglia: Focus on oxidative stress and energy metabolism
Get PDFCarnosine (β-alanyl-L-histidine) is a naturally occurring endogenous peptide widely distributed in excitable tissues such as the brain. This dipeptide possesses well-demonstrated antioxidant, anti-inflammatory, and anti-aggregation properties, and it may be useful for treatment of pathologies characterized by oxidative stress and energy unbalance such as depression and Alzheimer’s disease (AD). Microglia, the brain-resident macrophages, are involved in different physiological brain activities such synaptic plasticity and neurogenesis, but their dysregulation has been linked to the pathogenesis of numerous diseases. In AD brain, the activation of microglia towards a pro-oxidant and pro-inflammatory phenotype has found in an early phase of cognitive decline, reason why new pharmacological targets related to microglia activation are of great importance to develop innovative therapeutic strategies. In particular, microglia represent a common model of lipopolysaccharides (LPS)-induced activation to identify novel pharmacological targets for depression and AD and numerous studies have linked the impairment of energy metabolism, including ATP dyshomeostasis, to the onset of depressive episodes. In the present study, we first investigated the toxic potential of LPS + ATP in the absence or presence of carnosine. Our studies were carried out on human microglia (HMC3 cell line) in which LPS + ATP combination has shown the ability to promote cell death, oxidative stress, and inflammation. Additionally, to shed more light on the molecular mechanisms underlying the protective effect of carnosine, its ability to modulate reactive oxygen species production and the variation of parameters representative of cellular energy metabolism was evaluated by microchip electrophoresis coupled to laser-induced fluorescence and high performance liquid chromatography, respectively. In our experimental conditions, carnosine prevented LPS + ATP-induced cell death and oxidative stress, also completely restoring basal energy metabolism in human HMC3 microglia. Our results suggest a therapeutic potential of carnosine as a new pharmacological tool in the context of multifactorial disorders characterize by neuroinflammatory phenomena including depression and AD
Hyper-palatable foods in elementary school lunches: Availability and contributing factors in a national sample of US public schools
Get PDFBackground
School cafeterias are a major point of influence for child nutrition. United States federal legislation requires the presence of important nutrients in school meals. However, legislation overlooks the potential presence of hyper-palatable foods in school lunches, a hypothesized factor that may influence children’s eating behavior and obesity risk. The study sought to 1) quantify the prevalence of hyper-palatable foods (HPF) served in US elementary school lunches; and 2) determine whether food hyper-palatability varied based on school geographic region (East/Central/West), urbanicity (urban/micropolitan/rural), or meal item (entrée/side/fruit or vegetable).
Methods
Lunch menu data (N = 18 menus; N = 1160 total foods) were collected from a sample of six states that represented geographic regions of the United States (Eastern/Central/Western; Northern/Southern) and that had variability in urbanicity (urban, micropolitan, and rural) within each state. A standardized definition from Fazzino et al (2019) was used to identify HPF in lunch menus.
Results
HPF comprised almost half of foods in school lunches (M = 47%; SD = 5%). Compared to fruit/vegetable items, entrées were >23 times more likely to be hyper-palatable and side dishes were >13 times more likely to be hyper-palatable (p values .05). The majority of entrée and side items contained meat/meat alternatives and/or grains and likely aligned with the US federal reimbursable meal components of meat/meat alternatives and/or grains.
Conclusions and implications
HPF comprised almost half of foods offered in elementary school lunches. Entrées and side items were most likely to be hyper-palatable. US school lunches may be a key point of regular exposure to HPF among young children, a risk factor that may elevate child obesity risk. Public policy regulating HPF in school meals may be needed to protect children’s health
The networked micro-decision context: A new lens on transformative urban governance
Get PDFRecent large-scale societal disruptions, from the COVID-19 pandemic to intensifying wildfires and weather events, reveal the importance of transforming governance systems so they can address complex, transboundary, and rapidly evolving crises. Yet current knowledge of the decision-making dynamics that yield transformative governance remains scant. Studies typically focus on the aggregate outputs of government decisions, while overlooking their micro-level underpinnings. This is a key oversight because drivers of policy change, such as learning or competition, are prosecuted by people rather than organizations. We respond to this knowledge gap by introducing a new analytical lens for understanding policymaking, aimed at uncovering how characteristics of decision-makers and the structure of their relationships affect their likelihood of effectuating transformative policy responses. This perspective emphasizes the need for a more dynamic and relational view on urban governance in the context of transformation
Transmission risk of Oropouche fever across the Americas
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Vector-borne diseases (VBDs) are important contributors to the global burden of infectious diseases due to their epidemic potential, which can result in significant population and economic impacts. Oropouche fever, caused by Oropouche virus (OROV), is an understudied zoonotic VBD febrile illness reported in Central and South America. The epidemic potential and areas of likely OROV spread remain unexplored, limiting capacities to improve epidemiological surveillance.
Methods
To better understand the capacity for spread of OROV, we developed spatial epidemiology models using human outbreaks as OROV transmission-locality data, coupled with high-resolution satellite-derived vegetation phenology. Data were integrated using hypervolume modeling to infer likely areas of OROV transmission and emergence across the Americas.
Results
Models based on one-support vector machine hypervolumes consistently predicted risk areas for OROV transmission across the tropics of Latin America despite the inclusion of different parameters such as different study areas and environmental predictors. Models estimate that up to 5 million people are at risk of exposure to OROV. Nevertheless, the limited epidemiological data available generates uncertainty in projections. For example, some outbreaks have occurred under climatic conditions outside those where most transmission events occur. The distribution models also revealed that landscape variation, expressed as vegetation loss, is linked to OROV outbreaks.
Conclusions
Hotspots of OROV transmission risk were detected along the tropics of South America. Vegetation loss might be a driver of Oropouche fever emergence. Modeling based on hypervolumes in spatial epidemiology might be considered an exploratory tool for analyzing data-limited emerging infectious diseases for which little understanding exists on their sylvatic cycles. OROV transmission risk maps can be used to improve surveillance, investigate OROV ecology and epidemiology, and inform early detection
Geochemical properties of blue carbon sediments through an elevation gradient: study of an anthropogenically impacted coastal lagoon
Get PDFGlobal research is showing that coastal blue carbon ecosystems are vulnerable to climate change driven threats including accelerated sea-level rise and prolonged periods of drought. Furthermore, direct anthropogenic impacts present immediate threats through deterioration of coastal water quality, land reclamation, long-term impact to sediment biogeochemical cycling. These threats will invariably alter the future efficacy of carbon (C) sequestration processes and it is imperative that currently existing blue carbon habitats be protected. Knowledge of underlying biogeochemical, physical and hydrological interactions occurring in functioning blue carbon habitats is essential for developing strategies to mitigate threats, and promote conditions to optimise C sequestration/storage. In this current work, we investigated how sediment geochemistry (0–10 cm depth) responds to elevation, an edaphic factor driven by long-term hydrological regimes consequently exerting control over particle sedimentation rates and vegetation succession. This study was performed in an anthropogenically impacted blue carbon habitat along a coastal ecotone encompassing an elevation gradient transect from intertidal sediments (un-vegetated and covered daily by tidal water), through vegetated salt marsh sediments (periodically covered by spring tides and flooding events), on Bull Island, Dublin Bay. We determined the quantity and distributions of bulk geochemical characteristics in sediments through the elevation gradient, including total organic carbon (TOC), total nitrogen (TN), total metals, silt, clay, and also, 16 individual polyaromatic hydrocarbon’s (PAH’s) as an indication of anthropogenic input. Elevation measurements for sample sites were determined on this gradient using a LiDAR scanner accompanied by an IGI inertial measurement unit (IMU) on board a light aircraft. Considering the gradient from the Tidal mud zone (T), through the low-mid marsh (M) to the most elevated upper marsh (H), there were significant differences between all zones for many measured environmental variables. The results of significance testing using Kruskal–Wallis analysis revealed, that %C, %N, PAH (µg/g), Mn (mg/kg), TOC:NH4+ and pH are significantly different between all zones on the elevation gradient. The highest values for all these variables exists (excluding pH which followed a reverse trend) in zone H, decreasing in zone M and lowest in the un-vegetated zone T. TC content is 16 fold higher overall in vegetated (3.43 -21.84%) than uninhabited (0.21–0.56%) sediments. TN was over 50 times higher (0.24–1.76%), more specifically increasing in % mass on approach to the upper salt marsh with distance from the tidal flats sediments zone T (0.002–0.05%). Clay and silt distributions were greatest in vegetated sediments, increasing in % content towards upper marsh zones The retention of water, metals, PAHs, mud, chloride ions, NH4+, PO43− and SO42− increased with elevated C concentrations, concurrently where pH significantly decreased. Sediments were categorized with respect to PAH contamination where all SM samples were placed in the high polluted category. The results highlight the ability of Blue C sediments to immobilise increasing levels of C, N, and metals, and PAH with over time and with both lateral and vertical expansion. This study provides a valuable data set for an anthropogenically impacted blue carbon habitat predicted to suffer from sea-level rise and exponential urban development
Structural Elucidation of a Protective B Cell Epitope on Outer Surface Protein C (OspC) of the Lyme Disease Spirochete, Borreliella burgdorferi
Get PDFOuter surface protein C (OspC) plays a pivotal role in mediating tick-to-host transmission and infectivity of the Lyme disease spirochete, Borreliella burgdorferi. OspC is a helical-rich homodimer that interacts with tick salivary proteins, as well as components of the mammalian immune system. Several decades ago, it was shown that the OspC-specific monoclonal antibody, B5, was able to passively protect mice from experimental tick-transmitted infection by B. burgdorferi strain B31. However, B5’s epitope has never been elucidated, despite widespread interest in OspC as a possible Lyme disease vaccine antigen. Here, we report the crystal structure of B5 antigen-binding fragments (Fabs) in complex with recombinant OspC type A (OspCA). Each OspC monomer within the homodimer was bound by a single B5 Fab in a side-on orientation, with contact points along OspC’s α-helix 1 and α-helix 6, as well as interactions with the loop between α-helices 5 and 6. In addition, B5’s complementarity-determining region (CDR) H3 bridged the OspC-OspC′ homodimer interface, revealing the quaternary nature of the protective epitope. To provide insight into the molecular basis of B5 serotype specificity, we solved the crystal structures of recombinant OspC types B and K and compared them to OspCA. This study represents the first structure of a protective B cell epitope on OspC and will aid in the rational design of OspC-based vaccines and therapeutics for Lyme disease