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  1. Free, publicly-accessible full text available March 1, 2024
  2. Objectives: Diarrheal disease continues to be a significant cause of morbidity and mortality. We investigated how anomalies in monthly average temperature, precipitation, and surface water storage (SWS) impacted bacterial, and viral diarrhea morbidity in Taiwan between 2004 and 2015. Methods: A multivariate analysis using negative binomial generalized estimating equations was employed to quantify age- and cause-specific cases of diarrhea associated with anomalies in temperature, precipitation, and SWS. Results: Temperature anomalies were associated with an elevated rate of all-cause infectious diarrhea at a lag of 2 months, with the highest risk observed in the under-5 age group (incidence rate ratio [IRR]=1.03, 95% CI, 1.01-1.07). Anomalies in SWS were associated with increased viral diarrhea rates, with the highest risk observed in the under-5 age group at a 2-month lag (IRR= 1.27; 95% CI: 1.14, 1.42) and a lesser effect at a 1-month lag (IRR=1.18; 95% CI, 1.06-1.31). Furthermore, cause-specific diarrheal diseases were significantly affected by extreme weather events in Taiwan. Both extremely cold and hot conditions were associated with an increased risk of all-cause infectious diarrhea regardless of age, with IRRs ranging from 1.03 (95% CI, 1.02-1.12) to 1.18 (95% CI, 1.16-1.40).Conclusions: The risk of all-cause infectious diarrhea was significantly associated withmore »average temperature anomalies in the population aged under 5 years. Viral diarrhea was significantly associated with anomalies in SWS. Therefore, we recommend strategic planning and early warning systems as major solutions to improve resilience against climate change.« less
    Free, publicly-accessible full text available February 1, 2024
  3. Abstract

    Natural history collections assembled before modern‐day, anthropogenic declines in species occurrence and abundance can provide essential data for conservation and biogeographic research. Digitizing old, commonly ‘orphaned’ collections in small institutions without professional curators increases local community access to specimens, as well as global access to digitized data. We present a case study, documenting a 19th century freshwater mussel (Order: Unionoida) collection, which is part of the 'orphaned' natural history collections at Wesleyan University (Middletown, CT, USA). We curated this collection by identifying specimens according to present taxonomic practices, and using archival documents to recover metadata. Nearly 1900 specimens in 402 ‘lots’, representing 155 species, were photographed and catalogued. Three primary type specimens were identified; 64 species are on the IUCN Red List, with 4 extinct, and 28 Critically‐Endangered to Endangered. We created and publicly host online 3D models of imperiled species. These models enabled us to organize an exhibit of 3D prints of fragile specimens, and to study ecophenotypic variation of freshwater mussels along a river gradient. Our project documents the challenges and achievements of a case study illuminating the potential scientific value of, and revival strategies for, orphaned natural history collections.

  4. Abstract

    Covalent adaptable network (CAN) polymers doped with conductive nanoparticles are an ideal candidate to create reshapeable, rehealable, and fully recyclable electronics. On the other hand, 3D printing as a deterministic manufacturing method has a significant potential to fabricate electronics with low cost and high design freedom. In this paper, we incorporate a conductive composite consisting of polyimine CAN and multi-wall carbon nanotubes into direct-ink-writing 3D printing to create polymeric sensors with outstanding reshaping, repairing, and recycling capabilities. The developed printable ink exhibits good printability, conductivity, and recyclability. The conductivity of printed polyimine composites is investigated at different temperatures and deformation strain levels. Their shape-reforming and Joule heating-induced interfacial welding effects are demonstrated and characterized. Finally, a temperature sensor is 3D printed with defined patterns of conductive pathways, which can be easily mounted onto 3D surfaces, repaired after damage, and recycled using solvents. The sensing capability of printed sensors is maintained after the repairing and recycling. Overall, the 3D printed reshapeable, rehealable, and recyclable sensors possess complex geometry and extend service life, which assist in the development of polymer-based electronics toward broad and sustainable applications.

  5. Vitrimers with bond exchange reactions (BERs) are a class of covalent adaptable network (CAN) polymers at the forefront of recent polymer research. They exhibit malleable and self-healable behaviors and combine the advantages of easy processability of thermoplastics and excellent mechanical properties of thermosets. For thermally sensitive vitrimers, a molecular topology melting/frozen transition is triggered when the BERs are activated to rearrange the network architecture. Notable volume expansion and stress relaxation are accompanied, which can be used to identify the BER activation temperature and rate as well as to determine the malleability and interfacial welding kinetics of vitrimers. Existing works on vitrimers reveal the rate-dependent behaviors of the nonequilibrium network during the topology transition. However, it remains unclear what the quantitative relationship with heating rate is, and how it will affect the macroscopic stress relaxation. In this paper, we study the responses of an epoxy-based vitrimer subjected to a change in temperature and mechanical loading during the topology transition. Using thermal expansion tests, the thermal strain evolution is shown to depend on the temperature-changing rate, which reveals the nonequilibrium states with rate-dependent structural relaxation. The influences of structural relaxation on the stress relaxation behaviors are examined in both uniaxial tension andmore »compression modes. Assisted by a theoretical model, the study reveals how to tune the material and thermal-temporal conditions to promote the contribution of BERs during the reprocessing of vitrimers.« less