37200 research outputs found
Sort by
Incorporating the Influence of Vehicle Mix on Crash Frequency and Severity
No full textThe current approaches for crash frequency and severity prediction in the Highway Safety Manual (HSM) do not employ vehicle mix information. In this research effort, we build advanced alternatives to HSM methods while incorporating vehicle mix information. Two model systems—(a) multivariate Poisson-lognormal model and (b) negative binomial-ordered probit fractional split model—are estimated by incorporating vehicle mix variables. The developed model systems can also capture the influence of observed and unobserved heterogeneity of different independent variables including vehicle mix variables. We estimate the models for three facility types including Urban Arterial 4-Lane Divided segments, Rural 3-Leg STOP-Controlled and Rural 4-Leg STOP-Controlled intersections using data from four Highway Safety Information System (HSIS) states including California, Illinois, Minnesota, Washington, and three non-HSIS states including Connecticut, Florida, and Texas. For modeling crashes at each facility level, we adopt a pooled modeling technique that accounts for state-specific observed and unobserved heterogeneity in the pooled datasets. A comprehensive set of independent variables including traffic volume, vehicle mix indicators, roadway characteristics, and state-specific indicators are considered in the analysis. The model comparison exercise is conducted based on a comprehensive set of quantitative and qualitative metrics. The study highlights how different methodological approaches perform better for different facilities. The study findings also underscore how capturing the observed and unobserved impacts of vehicle mix variables improves model performance in crash frequency and severity dimensions across the facility types
Obesity Vs. Overweight Status: Differential Predictions to Poly-Substance Use in Young Adulthood
No full textBackground:
Though past research has identified links between higher weight status and substance use in young adulthood, prospective studies are scarce and mixed, the role of higher weight status on vaping is less clear, and little empirical work has examined differences between obesity vs. overweight on poly-substance use. The current study assessed the role of weight status on poly-substance use trajectories across young adulthood.Methods1,303 young adults (20.5 ± 2.3 years; 63% female; 41% Latina/o/x, 30% Asian-American/Asian, 18% Caucasian/White) from a public, urban university were surveyed at six-month intervals from spring 2021 (W1) to spring 2023 (W5). Weight status was measured at W1 with body mass index (BMI) and categorized into obese (BMI ≥ 30.0); overweight (BMI 25.0–29.9); healthy weight (BMI 18.5–24.9); and underweight (BMI \u3c 18.5). Past 30-day use of nicotine vaping, cigarette smoking, cannabis vaping, combustible cannabis, cannabis edibles, and binge drinking across waves were used to identify poly-substance use trajectories with parallel growth mixture modeling (PGMM).ResultsFour trajectories were identified: Nicotine/Tobacco Users and Binge Drinkers (7.2%); Poly-Users (9.8%); Moderate Cannabis Users and Binge Drinkers (18.7%); and Non-Users (64.3%). Obese young adults (vs. healthy weight) had lower odds of belonging to the Nicotine/Tobacco Users and Binge Drinkers trajectory [aOR = .24(.06-.99)] vs. Non-Users trajectory. Overweight young adults (vs. healthy weight) had higher odds of belonging to the Moderate Cannabis Users and Binge Drinkers trajectory [aOR = 1.94(1.25–3.03)] vs. Non-Users trajectory.ConclusionsOverweight young adults\u27 higher odds vs. obese young adults\u27 lower odds of belonging to poly-substance use trajectories suggest overweight young adults may be a key target group for poly-use public health initiatives. Poly-substance use differences between obese and overweight status indicate a greater need for specificity when evaluating relationships between higher weight status and substance use
More Than a Ramp: Rethinking School Design for Sensory and Cognitive Inclusion
No full textThis thesis advocates for the integration of the ASPECTSS framework, developed by Magda Mostafa, into legislative standards that would govern the design of educational environments that accommodate students with Autism Spectrum Disorder (ASD). Drawing on evidence from a case study demonstrating significant improvements in student behavior and overall satisfaction through ASPECTSS-based interventions, the thesis highlights the urgent need for these principles to move beyond voluntary adoption and rather, toward enforceable design mandates.
The ASPECTSS framework includes the seven following criterias; Acoustics, Spatial Sequencing, Escape Spaces, Compartmentalization, Transitions, Sensory Zoning, and Safety. This model provides a comprehensive and actionable approach to creating inclusive school environments. To ensure effective implementation, interdisciplinary collaboration among educators, occupational therapists, architects, and, critically, direct input from students and their families, is required. This collective expertise helps establish design standards that are firmly grounded in both lived experiences and specialized knowledge.
Finally, the thesis proposes a set of theoretical design guidelines modeled on the ADA standards, specifying criteria within each ASPECTSS category to visualize what future legislative frameworks could potentially look like. This thesis not only offers a potential solution to current challenges but also provides a critical analysis of the shortcomings in existing design standards and legislation
Largely Enhanced Out-Of-Plane Electromechanical Coupling Effects in Two-Dimensional Molybdenum-Disulfide/Boron-Nitride Heterostructures
Get PDFThe electromechanical coupling effects in two-dimensional (2D) transition metal dichalcogenides (TMDs) have attracted great interest. However, for 2D TMDs, piezoelectricity is confined to the basal plane, and the flexoelectricity-derived out-of-plane electromechanical response is usually faint, limiting the applications of this material family using the out-of-plane electromechanical effects. Here, this work reports a facile strategy to greatly enhance the out-of-plane electromechanical response of hexagonal molybdenum disulfide (2H-MoS2) nanoflakes by stacking monolayer hexagonal boron nitride (h-BN) on 2H-MoS2 nanoflakes to form MoS2/BN heterostructures. The deff/33 coefficient of MoS2/BN can reach a value comparable to that of commonly used wurtzite bulk piezoelectric materials, such as AlN and GaN. The strong out-of-plane electromechanical response of MoS2/BN is due to the breaking of the out-of-plane structural symmetry. Kelvin probe force microscopy (KPFM) results show an increased effective work function of MoS2/BN, indicating polar-structure formation at the heterostructure interface, which also accounts for the enhanced out-of-plane piezoresponse. This study gives an insight into the role of heterostructure engineering in the electromechanical performances of 2D TMDs, and provides this material family an opportunity for applications using out-of-plane electromechanical effects
Above a Toxic Burrito: Soil Amendments Including Biochar and Wood Mulch Can Improve Plant Survival on Urban Fill Soils
No full textSoil health is a neglected aspect of many construction projects involving restoration. Poor soils coupled with global warming exacerbates heat stress in plants. We examined a recent project completed by Environmental Services. In fill soils a year after construction in 2021, most of the planted 13,000 shrubs succumbed to excessive heat. Subsequent soil testing showed characteristics that can exacerbate water and heat stress, including sandy loam texture with big chunks of concrete and “urban fill”. Low soil organic matter also decreased water holding capacity. To improve soil conditions and plant growth as well as monitor outcomes, we set up a trial by amending the soil with 2 different compost and biochar products at 2 different rates. Imported soil areas were also de-compacted using machinery and about ½ of plants were mulched with wood chips. Each treatment had 4 replicate zones and Thimbleberry (Rubus parviflorus) was planted in 5 clusters of 10 plants each. Each plant was monitored annually for 3 years. One “Biotope”/biochar product increased survival by 16 % (+/- 12) (30% average survival) over the control (13% survival), and the “standard compost/biochar” product had a marginal increase in survival (18%). Wood chip mulch plus Biotope increased survival to 51%. Heights and widths of plants didn’t differ across treatments. One compost product shows promise on improving survival outcomes, but it is unclear if it was due to the biochar or other site conditions. Soil conditions should take priority when designing restoration projects
Identification and Analysis on Surface Deformation in the Urban Area of Nanchang Based on Ps-Insar Method
Get PDFInterferometric Synthetic Aperture Radar (InSAR) technology has emerged as a vital tool for monitoring surface deformation due to its high accuracy and spatial resolution. With the rapid economic development of Nanchang, extensive infrastructure development and construction activities have significantly altered the urban landscape. Underground excavation and groundwater extraction in the region are potential contributors to surface deformation. This study utilized Sentinel-1 satellite data, acquired between September 2018 and May 2023, and applied the Permanent Scatterer Interferometric Synthetic Aperture Radar (PS-InSAR) technique to monitor surface deformation in Nanchang’s urban area. The findings revealed that surface deformation rates in the study area range from −10 mm/a to 6 mm/a, with the majority of regions remaining relatively stable. Approximately 99.9% of the monitored points exhibited deformation rates within −5 mm/a to 5 mm/a. However, four significant subsidence zones were identified along the Gan River and its downstream regions, with a maximum subsidence rate reaching 9.7 mm/a. Historical satellite imagery comparisons indicated that certain subsidence areas are potentially associated with construction activities. Further analysis integrating subsidence data, monthly precipitation, and groundwater depth revealed a negative correlation between surface deformation in Region A and rainfall, with subsidence trends aligning with groundwater level fluctuations. However, such a correlation was not evident in the other three regions. Additionally, water level data from the Xingzi Station of Poyang Lake showed that only Region A’s subsidence trend closely corresponds with water level variations. We conducted a detailed analysis of the spatial distribution of soil types in Nanchang and found that the soil types in areas of surface deformation are primarily Semi-hydromorphic Soils and Anthropogenic Soils. These soils exhibit high compressibility, making them prone to compaction and significantly influencing surface deformation. This study concludes that localized surface deformation in Nanchang is primarily driven by urban construction activities and the compaction of artificial fill soils, while precipitation also has an impact in certain areas
Youth Experiences of Participation, Inclusion, and Influence Within a Youth-Serving Organization Implementing Participatory Processes
Get PDFThe youth development field has undergone shifts and reconstructions in how youth are conceived, impacting the approaches of youth-serving programs attempting to facilitate learning, growth, and engagement. Evolving views inform how policymakers, funders, and youth-serving agencies perceive and relate with youth. In turn, these dynamics influence how youth learn to think about themselves, others, and the world. Dominant discourse regarding youth development has been shifting from a deficit-based to an asset-based lens, with the proliferation of Positive Youth Development (PYD) frameworks, which seek to cultivate internal strengths and positive developmental outcomes rather than just prevent negative behaviors and outcomes. Despite the presumed intention of PYD to view youth more holistically, significant youth lived experiences, and environmental influences are still neglected. Youth development researchers and practitioners have criticized the asset-based approach for lacking an awareness of the socio-political forces impacting youth development, including pervasive inequities, oppression, and injustice, particularly for youth of color. This awareness reflects an essential contextualization that drives an applied response. As youth-serving institutions attempt to integrate this awareness many start with creating an equity statement with an intent to review and adjust program policies and practices. However, many struggle with incorporating practices, grounded in critical awareness, that would counter the baseline status quo of youth exclusion via more inclusive and participatory methods.
This constructivist-oriented qualitative dissertation sought to learn from youth experiences of inclusion, participation, and influence as a youth-serving organization implemented an equity and social justice framework, including youth participatory processes. Informed by critical race theory, sociocultural theory, and grounded in the Social Justice Development Model (SJYDM), this study focused on participation, inclusion, and influence as essential indicators of the intersection of critical awareness and participatory approaches.
With the aim of elevating youth voice, 10 focus groups were conducted across the middle and high school-based programs of a prominent youth-serving organization, as well as the organization\u27s Youth Advisory Council (YAC). Across these focus groups, 35 youth participants discussed their experiences within the program, resulting in transcripts that were analyzed with a qualitative thematic analysis approach. This iterative analysis provided a rich description of youth experiences with regard to participation, inclusion, influence, and related subthemes. Youth repeatedly discussed the significance of how their relationships with adult facilitators impacted their experiences of participation, inclusion, and influence. When an adult was perceived as caring, flexible, supportive, and able to relate reciprocally, youth felt respected, safe, and supported to participate. Youth also shared how important a sense of belonging was to their participation and feelings of inclusion.
Additionally, youth were attuned to the degree to which they perceived adults responding to oppressive actions, across the school. Interestingly, they described minimal opportunities to discuss identity, power, and oppression despite the pervasiveness of these elements in their stories of differential treatment across the school setting. They also expressed hesitance to have more influence or power, relating this to arrogance and punitive methods of engagement. These discussions are contextualized within the presence or lack thereof of critical awareness education and participatory methods.
Analysis of these discussions is considered with regard to the literature on youth-participatory methods and critical awareness. Implications for further research and practice implications are addressed
Pumped Storage Hydropower in the United States: Emerging Importance, Environmental and Social Impacts, and Critical Considerations
Get PDFPumped storage hydropower is a widely used, long-duration energy storage system that sits squarely at the water-energy nexus. Bold decarbonization goals have propelled a rapid resurgence of interest in pumped storage hydropower in the US, given its ability to provide bulk energy storage, manage grid reliability, and support increasing integration of variable renewable energy sources. Drawing on published research from both technical and social science perspectives, this paper provides an overview of pumped storage hydropower technology, the project development pipeline, potential social and environmental impacts, including a comparison of open-loop and closed-loop design configurations, and critical considerations for project development. In contrast to all existing pumped storage hydropower projects in the US that are open-loop and located on natural water bodies, this review finds that over 80% of proposed projects are closed-loop designs, due to their siting flexibility away from natural water bodies and purportedly lower social and environmental impacts. However, issues around projects, including concerns over permitting and consultation processes and conflicts over siting, water resources, and Indigenous lands, are emerging more frequently given the planned expansion of projects in the arid US West and near Tribal lands. These issues and conflicts are not necessarily lowered by closed-loop technology. The early stage of project development offers an opportunity to design projects that include community input and minimize tradeoffs. In turn, this will require taking a critical look at each pumped storage hydropower project as well as understanding community perceptions and the lifecycle impacts of this technology
Faculty Senate Monthly Packet January 2025
Get PDFThe January 6, 2025 monthly packet includes the agenda, appendices, and the Faculty Senate minutes and attachments from the meeting held January 6, 2025
Influence of Inselbergs on Bat Diversity in Afrotropical Ecosystems
No full textHumans are altering biological communities on local to global scales, driving profound changes in biodiversity and ecosystem functioning. However, significant gaps and biases in biodiversity data hinder our understanding of ecosystem interactions, making it challenging to develop effective, data-driven policies to protect remaining biodiversity. Bats, the second most species-rich groups of mammals, have a global distribution, and perform a broad array of vital ecosystem functions. Their diversity peaks in the tropics, where they often constitute more than 50% of mammal species diversity. The Afrotropics host substantial bat diversity, yet have historically been perceived as having lower species richness compared to other tropical regions. Recent studies, however, reveal that this perception has been influenced by sampling biases and cryptic diversity, masking the true extent of Afrotropical bat diversity. An important yet understudied component of Afrotropical landscapes are inselbergs, or isolated rock outcrops forming discrete ecosystems. The unique habitats play a vital role in shaping local and regional bat diversity by providing varied niche space, supporting hydrological networks, and contributing to ecosystem stability.
In the first study (Chapter 2), we examined the morphological and molecular (mitochondrial Cytochrome b) variation within the Tropical African vespertilionid bat genus Pseudoromicia. This analysis revealed the existence of a new species Pseudoromicia mbamminkom, from the Mbam Minkom Massif in the Centre Region of Cameroon. Phylogenetic analysis placed this species within a clade alongside P. roseveari and P. kityoi. Pseudoromicia mbamminkom was diagnosed through sequence data, as well as craniodental characters although it is morphologically similar to its sister taxon, P. kityoi, from Uganda. We proposed assigning the species to the IUCN Data Deficient category, as the description is based on the capture of a single specimen. However, its conservation status might warrant concern, given the threats to the Mbam Minkom Massif ecosystem from insufficient legal protection and increasing human pressure.
In the second study (Chapter 3), we reported findings from two expeditions (2019 and 2022) to the Mbam Minkom Massif and describe the bat fauna of this tropical inselberg. Over the two expeditions, 36 bat species from 21 genera and six families were recorded. Notably, our findings include two new species records for Cameroon, additional records of Pseudoromicia mbamminkom, and the presence of several threatened species. Detailed species accounts are provided, including locality records, capture sites, taxonomic notes, and echolocation call data. Sampling curves indicated a species richness of 42 with adequate coverage but suggested the potential for undetected species, emphasizing the need for further surveys to develop a comprehensive species checklist. This study highlighted the remarkable diversity and ecological importance of the Mbam Minkom Massif and its surrounding forest, an ecosystem under threat from deforestation and increasing human activity.
In the final study (Chapter 4), we investigated the influence of the Mbam Minkom Massif on bat diversity by comparing the forest near the inselberg to a forest distant to the inselberg in homogenous lowlands. Using a multifaceted approach, we examined alpha and beta taxonomic, functional, and phylogenetic diversity. Results showed significantly higher taxonomic and functional diversity near the inselberg, likely due to increased habitat complexity and rocky terrain suitable for roosting. Notably, three cave-roosting species (R. landeri, Hipposideros curtus, and Rousettus aegyptiacus) were detected exclusively near the inselberg. Phylogenetic alpha diversity showed similar patterns but with less pronounced differences and no significant variation in richness or diversity. The observed patterns of taxonomic, functional, and phylogenetic diversity near the inselberg reflect the interplay of localized ecological factors and broader biogeographic processes shaping bat communities near the inselberg and in the distant, homogenous lowland landscape. These findings highlight the critical role of Mbam Minkom Massif in promoting taxonomic and functional diversity while enhancing the ecological resilience of the local bat community.
In closing (Chapter 5), we discuss the implications of our findings, highlighting the role of inselbergs as drivers of bat taxonomic and functional diversity, and facilitators of ecosystem resilience in the Afrotropics. These findings enhance our understanding of bat diversity and the mechanisms shaping it in a highly biodiverse region, currently facing increased pressure from anthropogenic changes. This body of work contributes to the limited research on how inselbergs influence faunal diversity, particularly in the Afrotropics. As biodiversity loss continues to accelerate, studies such as this provide critical insights into the factors that shape and sustain biodiversity. This research can be used to inform strategies to protect inselberg ecosystems, which not only contribute to local and regional biodiversity, but also serve as refuges and microrefugia for species