published journal article
published journal article
MS Thesis
The purpose of this study is to provide a comprehensive analysis of UC Irvine affiliate transportation patterns and behavior. Through this analysis, recommendations on how to best promote more sustainable transportation on the UC Irvine campus was made to the two study sponsors, UCI Transportation and Distribution Services (TDS) and Anteater Express. With the assistance of TDS, an online survey was sent through a campus-wide email, and achieved overall sample size n = 2,034. Due to technical errors, freshmen did not receive the email. However, through the assistance of UCI Student Housing, surveys were sent to on-campus freshmen. Consequently, this still left out the off-campus freshmen and this exclusion impacted our analysis. Set aside from this limitation, the current study provided a framework, to the study sponsors, for an unprecedented comprehensive campus-wide transportation analysis at UC Irvine based on the study sponsor’s goals and objectives. Results indicate there is room for improving the use of alternative transportation for UCI affiliates who live within the City of Irvine in which UC Irvine is located. One recommendation pertains to increasing awareness of more sustainable transportation option and shedding light on transportation impacts early on such as during incoming student orientation and when students move out of the dorms and into local rental communities. That way when new UCI affiliates attempt to get acclimated to their new surroundings, with the early information, they can get the idea to explore alternative transportation as a potential way to be included within their daily life.
published journal article
BACKGROUND AND AIM[|]Urban biodiversity has a profound impact on human health that has not been thoroughly investigated. Little research exists regarding the associations between plant species richness and preterm birth (PTB). We aimed to examine the relationships between PTB and plant species richness, and the effect modifications by maternal characteristics, air pollution, ambient temperature, and the coronavirus disease (COVID-19) pandemic.[¤]METHOD[|]Clinical and sociodemographic data were obtained from Kaiser Permanente Southern California electronic health records in 2015–2021. PTB was defined as gestational age at birth less than 37 weeks. Maternal residential plant species diversity data were extracted from a wild vascular plant species diversity map across California urban areas at 5km resolution, and the maternal residential green space exposure data were assessed from satellite-based images (Normalized Difference Vegetation Index (NDVI) and land-cover green space). Multilevel logistic regressions were applied to examine the association between PTB and plant species diversity, after controlling for maternal age, race/ethnicity, education, and median household income. We also examined the effect modifications by maternal characteristics, air pollution, ambient temperature, and COVID pandemic (delivery before or during the pandemic) factors.[¤]RESULTS[|]In total, we included 302,266 births occurring between January 1, 2015, and December 31, 2021, with 21,421 (7.1%) PTB cases. Plant species richness in 2500m buffer showed a protective association with PTB (odds ratio [OR]: 0.980, 95% CI: 0.964, 0.996). The association persisted after further adjustments for NDVI and land-cover green space. The risk of PTB associated with plant species richness were significantly lower among mothers having a college degree, living in neighborhood with higher levels of O3 and average ambient temperature, and during the pandemic.[¤]CONCLUSIONS[|]This study found that maternal exposure to higher plant species diversity was associated with a decreased risk of PTB. Our findings suggest a complex interplay of sociodemographic and environmental factors influencing PTB risks.[¤]
book/book chapter
MS Thesis
conference paper
Phd Dissertation
published journal article
published journal article
Opinions regarding emergent sustainable transportation alternatives, such as bikeshare and e-scooters, and more traditional green alternatives like public transit, spread through social networks via opinion diffusion mechanisms, like word-of-mouth and mass media. The impact of social media on diffusion of sustainable mobility opinions is not well-understood given the present lack of data. To address this gap, this paper introduces a modeling framework for the impact of social media on opinion diffusion. Inspired by Roger’s diffusion theory, the framework applies different learning mechanisms (e.g., word-of-mouth and mass media) in network architectures to explore the effects of network topology on acceptance of green travel alternatives using conceptual idealizations of the complex processes involved in diffusion interactions. We present a dynamic agent-based simulation methodology capturing the impact of information and communications technology (ICT) like social media on diffusion of environmentally friendly travel mode consideration through social networks. The agent-based models provide visual comparisons of the effects of network structure and social media influence on opinion diffusion, the way opinions spread, and which agents exhibit the strongest influence. We identify types of social media influencers that most effectively encourage adoption of sustainable transportation alternatives and present an illustrative framework of the mechanisms that drive opinion diffusion. Exploratory findings suggest that: (1) scale-free networks provide the slowest initial diffusion rate but the greatest overall diffusion over time, (2) the most effective behavior incentivization strategies depend on network structure, (3) in scale-free networks, increasing the number of initial opinion leaders improves diffusion, while increasing the number of communication encounters within the network over the first year following product deployment does not noticeably improve diffusion, and (4) providing smaller financial incentives to a greater number of opinion leaders is the best strategy.