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Creators/Authors contains: "Lucas, D"

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  1. Free, publicly-accessible full text available May 30, 2026
  2. ABSTRACT Plio-Pleistocene sediments from the southwestern Florida Peninsula contain an extraordinary density and diversity of marine mollusk and vertebrate fossils which, collectively, document major faunal shifts on the Florida Platform through a period of profound environmental change. Systematic study of these fossil assemblages and the environments in which they lived has been limited, however, by: i) a lack of outcrop sections spanning the full Plio-Pleistocene stratigraphy of the region and ii) major uncertainties in correlation between previous study sites due to extreme lateral variability in coastal paleoenvironments. Here, we describe a new stratigraphic section from Florida Shell Quarry in Charlotte County, Florida, which contains fossil-rich deposits of each major Plio-Pleistocene unit in the area (the Tamiami, Caloosahatchee, Bermont, and Fort Thompson formations). Bulk sediment samples collected from 22 horizons were used to broadly characterize stratigraphic variations in lithology and faunal content. Predation intensity was estimated from drill-hole frequency among populations of the bivalve Chione spp. While all studied formations were mainly deposited under marine conditions, both lithologic and faunal facies shifts within the Caloosahatchee and Bermont units indicate periods of pronounced freshwater influence. Faunal diversity is relatively high in the Tamiami, Caloosahatchee, and Bermont units but declines in the Fort Thompson. Similarly, predation intensity is high in the Caloosahatchee and Bermont units but lower in the Fort Thompson at the sampled sites. In addition to characterizing changes in the local paleoenvironment, we propose a sequence stratigraphic model for the section based on inferred local sea-level fluctuations. We leverage this sequence stratigraphic framework to correlate the Florida Shell section with other studied sections in the Charlotte Harbor area. The development of this new site provides a workable basis for more detailed studies of the long-term paleoecological and paleoenvironmental evolution of southwestern Florida. 
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    Free, publicly-accessible full text available April 7, 2026
  3. Free, publicly-accessible full text available May 22, 2026
  4. To pursue transdisciplinary education, bringing together different disciplinary perspectives is necessary. As two graduate researchers, in engineering technology and anthropology, on a National Science Foundation (NSF) Improving Undergraduate STEM Education research project, we want to embody and explore our role in the journey to pursue transdisciplinary education. Our familiarity with higher education as students, our different disciplinary backgrounds and lived experiences, and our training as an engineering technology educator and a social scientist contribute greatly to the advancement of understanding the project. Harnessing our combined expertise enables us to see collaborative co-teaching, group learning, and student engagement in new ways. Often transdisciplinary education research is approached from siloed disciplines or from a single perspective and not inclusive of graduate students' perspectives. We find ourselves working on a collaborative cross-college project between three different colleges, Business, Engineering Technology, and Liberal Arts, where faculty and students are co-teaching and co-learning in a series of design and innovation courses. A key element of this project is gathering and using stakeholder data from students, faculty, and administrators. Midway through our three-year project, the NSF project’s external reviewer highlighted the crucial value added of having graduate researchers looking at transforming higher education towards transdisciplinarity. With that in mind, we offer some guiding thoughts about collaborative research among graduate students and faculty from different academic disciplines. This includes tips on how we collaborated in coding, analysis, and data presentations. Using project examples, we will discuss how we used tools for collaboration such as NVivo Teams and Microsoft Teams; these platforms aided in contributing to the iterative research design of this project and research outputs. Our process was strengthened by active participation in project meetings with faculty, educational community events, and data review sessions to reach data consensus. We have noticed how transdisciplinarity can transform undergraduate learning and encourage cross-college faculty collaboration. We will reflect on the significance of collaboration at all levels of higher education. Furthermore, this experience has set us on the path to becoming transdisciplinary scholars ourselves. 
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  5. Abstract A limitation in fine-tuned tree-ring radiocarbon (14C) data is normally associated with overall data uncertainty. Tree-ring14C data variance as a result of sample heterogeneity can be reduced by adopting best practices at the time of sample collection and subsequent preparation and analysis. Variance-reduction of14C data was achieved by meticulous sample handling during increment core or cross-sectional cuttings, in-laboratory wood reductions, and cellulose fiber homogenization of whole rings. To demonstrate the performance of those procedures to final14C results, we took advantage of the replicated data from assigned calendar years of two Pantropical post-1950 AD tree-ring14C reconstructions. TwoCedrela fissilisVell. trees spaced 22.5 km apart, and two trees of this species together with onePeltogyne paniculataBenth tree spaced 0.2 to 5 km apart were sampled in a tropical dry and moist forest, respectively. Replicate14C data were then obtained from grouped tree-ring samples from each site. A total of 88% of the replicated14C results fell into a remarkably consistent precision/accuracy range of 0.3% or less, even though multiple tree species were used as pairs/sets. This finding illustrates how adopting a few simple strategies, in tandem with already established chemical extraction procedures and high-precision14C analysis, can improve14C data results of tropical trees. 
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  6. Transdisciplinary learning can be viewed as the pinnacle of integrated teaching, whereas the acquisition/application of knowledge/skills are driven by compelling socio-scientific problems that demand the transcending of disciplinary boundaries and the blending of diverse viewpoints/practices to develop innovative solutions over time. With a variety of educational transformation initiatives happening at universities, DT programs can help shape the way that undergraduate learning occurs. So how do DT programs leverage their value related to transdisciplinary learning through design/innovation practice to reach new audiences while also sustaining programs that develop teachers? To provide an answer, this poster will highlight a transdisciplinary program, titled Mission Meaning Making (M3), that was developed to provide a new cross-college learning experience for undergraduate students focused on design and innovation. The M3 program has been created to synergize the key strengths of three partnering units/disciplines (DT, anthropology, and business) to prepare undergraduates for addressing contemporary challenges in innovative, and transdisciplinary ways. The poster will provide details/research related to the M3 program and explore how DT can strive to make a broader impact on campuses. 
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  7. Abstract Femtosecond laser‐induced damage threshold (LIDT) testing is carried out at 515 nm on 4‐mm‐sized metalens arrays that are manufactured by direct nanoimprinting of a TiO2nanoparticle (NP)‐based ink containing either polymeric or inorganic binders. The all‐inorganic TiO2metalenses exhibit ≈80% absolute focusing efficiency and demonstrate an LIDT of ≈90 mJ cm−2based on a single‐shot determination using Liu's method, while the metalenses with the polymeric binder achieve ≈137 mJ cm−2and an efficiency of ≈76%. Despite the higher LIDT of the TiO2‐polymer composite metalenses in the single‐shot experiment, these lenses exhibit significant damage at fluences as low as ≈8 mJ cm−2when subjected to ≈6 × 10⁸ pulses at 60 kHz. On the other hand, the all‐inorganic metalenses remain intact under identical conditions at ≈64 mJ cm−2. That is, the inorganic binder provides superior long‐term stability relative to the polymeric binder and is a more viable solution for high‐energy applications. Structural damages observed in nanostructures result in a reduced deflection efficiency and increase light scattering at the focal plane of the metalens. The LIDT testing is also performed in the nanosecond regime at 532 and 1064 nm with the all‐inorganic metalenses, yielding thresholds of ≈0.5 and ≈5 J cm−2, respectively. 
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    Free, publicly-accessible full text available October 24, 2026
  8. There have been numerous demands for enhancements in the way undergraduate learning occurs today, especially at a time when the value of higher education continues to be called into question (The Boyer 2030 Commission, 2022). One type of demand has been for the increased integration of subjects/disciplines around relevant issues/topics—with a more recent trend of seeking transdisciplinary learning experiences for students (Sheets, 2016; American Association for the Advancement of Science, 2019). Transdisciplinary learning can be viewed as the holistic way of working equally across disciplines to transcend their own disciplinary boundaries to form new conceptual understandings as well as develop new ways in which to address complex topics or challenges (Ertas, Maxwell, Rainey, & Tanik, 2003; Park & Son, 2010). This transdisciplinary approach can be important as humanity’s problems are not typically discipline specific and require the convergence of competencies to lead to innovative thinking across fields of study. However, higher education continues to be siloed which makes the authentic teaching of converging topics, such as innovation, human-technology interactions, climate concerns, or harnessing the data revolution, organizationally difficult (Birx, 2019; Serdyukov, 2017). For example, working across a university’s academic units to collaboratively teach, or co-teach, around topics of convergence are likely to be rejected by the university systems that have been built upon longstanding traditions. While disciplinary expertise is necessary and one of higher education’s strengths, the structures and academic rigidity that come along with the disciplinary silos can prevent modifications/improvements to the roles of academic units/disciplines that could better prepare students for the future of both work and learning. The balancing of disciplinary structure with transdisciplinary approaches to solving problems and learning is a challenge that must be persistently addressed. These institutional challenges will only continue to limit universities seeking toward scaling transdisciplinary programs and experimenting with novel ways to enhance the value of higher education for students and society. This then restricts innovations to teaching and also hinders the sharing of important practices across disciplines. To address these concerns, a National Science Foundation Improving Undergraduate STEM Education project team, which is the topic of this paper, has set the goal of developing/implementing/testing an authentically transdisciplinary, and scalable educational model in an effort to help guide the transformation of traditional undergraduate learning to span academics silos. This educational model, referred to as the Mission, Meaning, Making (M3) program, is specifically focused on teaching the crosscutting practices of innovation by a) implementing co-teaching and co-learning from faculty and students across different academic units/colleges as well as b) offering learning experiences spanning multiple semesters that immerse students in a community that can nourish both their learning and innovative ideas. As a collaborative initiative, the M3 program is designed to synergize key strengths of an institution’s engineering/technology, liberal arts, and business colleges/units to create a transformative undergraduate experience focused on the pursuit of innovation—one that reaches the broader campus community, regardless of students’ backgrounds or majors. Throughout the development of this model, research was conducted to help identify institutional barriers toward creating such a cross-college program at a research-intensive public university along with uncovering ways in which to address these barriers. While data can show how students value and enjoy transdisciplinary experiences, universities are not likely to be structured in a way to support these educational initiatives and they will face challenges throughout their lifespan. These challenges can result from administration turnover whereas mutual agreements across colleges may then vanish, continued disputes over academic territory, and challenges over resource allotments. Essentially, there may be little to no incentives for academic departments to engage in transdisciplinary programming within the existing structures of higher education. However, some insights and practices have emerged from this research project that can be useful in moving toward transdisciplinary learning around topics of convergence. Accordingly, the paper will highlight features of an educational model that spans disciplines along with the workarounds to current institutional barriers. This paper will also provide lessons learned related to 1) the potential pitfalls with educational programming becoming “un-disciplinary” rather than transdisciplinary, 2) ways in which to incentivize departments/faculty to engage in transdisciplinary efforts, and 3) new structures within higher education that can be used to help faculty/students/staff to more easily converge to increase access to learning across academic boundaries. 
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