- ItemOpen AccessElectrothermal performance of heaters based on laser-induced graphene on aramid fabric(Colorado State University. Libraries, 2022) Naseri, Iman, author; Ziaee, Morteza, author; Nilsson, Zach N., author; Lustig, Danielle R., author; Yourdkhani, Mostafa, author; American Chemical Society, publisherNanostructured heaters based on laser-induced graphene (LIG) are promising for heat generation and temperature control in a variety of applications due to their high efficiency as well as a fast, facile, and highly scalable fabrication process. While recent studies have shown that LIG can be written on a wide range of precursors, the reports on LIG-based heaters are mainly limited to polyimide film substrates. Here, we develop and characterize nanostructured heaters by direct writing of laser-induced graphene on nonuniform and structurally porous aramid woven fabric. The synthesis and writing of graphene on aramid fabric is conducted using a 10.6 μm CO2 laser. The quality of laser-induced graphene and electrical properties of the heater fabric is tuned by controlling the lasing process parameters. Produced heaters exhibit good electrothermal efficiency with steady-state temperatures up to 170 °C when subjected to an input power density of 1.5 W cm–2. In addition, the permeable texture of LIG–aramid fabric heaters allows for easy impregnation with thermosetting resins. We demonstrate the encapsulation of fabric heaters with two different types of thermosetting resins to develop both flexible and stiff composites. A flexible heater is produced by the impregnation of LIG–aramid fabric by silicone rubber. While the flexible composite heater exhibits inferior electrothermal performance compared to neat LIG–aramid fabric, it shows consistent electrothermal performance under various electrical and mechanical loading conditions. A multifunctional fiber-reinforced composite panel with integrated de-icing functionality is also manufactured using one ply of LIG–aramid fabric heater as part of the composite layup. The results of de-icing experiments show excellent de-icing capability, where a 5 mm thick piece of ice is completely melted away within 2 min using an input power of 12.8 W.
- ItemOpen AccessEvaluating the consistency of subjective activity assessments and their relation to cognition in older adults(Colorado State University. Libraries, 2021-07-28) Hatt, Cassandra R., author; Brydges, Christopher R., author; Mogle, Jacqueline A., author; Sliwinski, Martin J., author; Bielak, Allison A. M., author; MDPI, publisher(1) Background: Research examining whether activity engagement is related to cognitive functioning in older adults has been limited to using retrospective reports of activity which may be affected by biases. This study compared two measurements (estimated weekly versus reported daily), and whether these activity assessments were related to cognition in older adults; (2) Methods: Participants from US (n = 199) and Australian (n = 170) samples completed a weekly estimate of activity, followed by 7 consecutive days of daily reporting. Differences between weekly estimates and daily reports were found, such that estimations at the weekly level were lower than self-reported daily information. Multivariate multiple regression was used to determine whether total activity, activity domains and the discrepancy between assessment types (i.e., weekly/daily) predicted cognitive performance across three cognitive domains (fluid, verbal, memory); (3) Results: When activity assessments were totaled, neither predicted cognition; however, when activity was grouped by domain (cognitive, social, physical), different domains predicted different cognitive outcomes. Daily reported cognitive activity significantly predicted verbal performance (β = 1.63, p = 0.005), while weekly estimated social activity predicted memory performance (β = –1.81, p = 0.050). Further, while the magnitude of discrepancy in total activity did not significantly predict cognitive performance, domain specific differences did. Differences in physical activity reported across assessments predicted fluid performance (β = –1.16, p = 0.033); (4) Conclusions: The significant discrepancy between the measurement types shows that it is important to recognize potential biases in responding when conducting activity and cognition research.
- ItemOpen AccessThe tempo and mode of angiosperm mitochondrial genome divergence inferred from intraspecific variation in Arabidopsis thaliana(Colorado State University. Libraries, 2020-01-21) Wu, Zhiqiang, author; Waneka, Gus, author; Sloan, Daniel B., author; Genetics Society of America, publisherThe mechanisms of sequence divergence in angiosperm mitochondrial genomes have long been enigmatic. In particular, it is difficult to reconcile the rapid divergence of intergenic regions that can make non-coding sequences almost unrecognizable even among close relatives with the unusually high levels of sequence conservation found in genic regions. It has been hypothesized that different mutation/repair mechanisms act on genic and intergenic sequences or alternatively that mutational input is relatively constant but that selection has strikingly different effects on these respective regions. To test these alternative possibilities, we analyzed mtDNA divergence within Arabidopsis thaliana, including variants from the 1001 Genomes Project and changes accrued in published mutation accumulation (MA) lines. We found that base-substitution frequencies are relatively similar for intergenic regions and synonymous sites in coding regions, whereas indel and nonsynonymous substitutions rates are greatly depressed in coding regions, supporting a conventional model in which mutation/repair mechanisms are consistent throughout the genome but differentially filtered by selection. Most types of sequence and structural changes were undetectable in 10-generation MA lines, but we found significant shifts in relative copy number across mtDNA regions for lines grown under stressed vs. benign conditions. We confirmed quantitative variation in copy number across the A. thaliana mitogenome using both whole-genome sequencing and droplet digital PCR, further undermining the classic but oversimplified model of a circular angiosperm mtDNA structure. Our results suggest that copy number variation is one of the most fluid features of angiosperm mitochondrial genomes.
- ItemOpen AccessMillennial consumers' responses to cause-related marketing in support of LGBTQ homeless youth(Colorado State University. Libraries, 2019-08-14) Hensley, Cammie, author; Diddi, Sonali, author; Hyllegard, Karen, author; MDPI, publisherThis study explored Millennial consumers' responses to a cause-related marketing (CRM) initiative for a sensitive social cause—lesbian, gay, bisexual, transgender and queer (LGBTQ) homeless youth. Qualitative and quantitative research methods were employed to examine the effctiveness of CRM in generating financial support for LGBTQ homeless youth. Findings revealed that self-cause congruence may be an important factor in determining Millennial consumers' responses to a CRM initiative for LGBTQ homeless youth; whereas, message frame/appeal may be less important for generating response to such an initiative. Findings also indicated that gender, information processing, guilt, and skepticism influenced Millennial consumers' attitudes toward brand, attitudes toward cause, and behavioral intentions toward the CRM initiative. These findings offer implications for brands/companies that may wish to engage in CRM initiative in support of sensitive social causes. By addressing a sensitive social cause-LGBTQ homeless youth-findings provide an original contribution to the CRM literature. Findings reveal that self-cause congruence is an important predictor of behavioral intention toward the LGBTQ social cause. This provides an implication for marketers who want to target their relationship-building efforts toward individuals who have demonstrated prior engagement with a social cause. Findings also have implications for brands/companies that wish to develop CRM initiatives for controversial causes.
- ItemOpen AccessThe mmpL3 interactome reveals a complex crosstalk between cell envelope biosynthesis and cell elongation and division in mycobacteria(Colorado State University. Libraries, 2019-07-24) Belardinelli, Juan Manuel, author; Stevens, Casey M., author; Li, Wei, author; Tan, Yong Zi, author; Jones, Victoria, author; Mancia, Filippo, author; Zgurskaya, Helen I., author; Jackson, Mary, author; Springer Nature Publishing, publisherIntegral membrane transporters of the Mycobacterial Membrane Protein Large (MmpL) family and their interactome play important roles in the synthesis and export of mycobacterial outer membrane lipids. Despite the current interest in the mycolic acid transporter, MmpL3, from the perspective of drug discovery, the nature and biological significance of its interactome remain largely unknown. We here report on a genome-wide screening by two-hybrid system for MmpL3 binding partners. While a surprisingly low number of proteins involved in mycolic acid biosynthesis was found to interact with MmpL3, numerous enzymes and transporters participating in the biogenesis of peptidoglycan, arabinogalactan and lipoglycans, and the cell division regulatory protein, CrgA, were identified among the hits. Surface plasmon resonance and co-immunoprecipitation independently confirmed physical interactions for three proteins in vitro and/or in vivo. Results are in line with the focal localization of MmpL3 at the poles and septum of actively-growing bacilli where the synthesis of all major constituents of the cell wall core are known to occur, and are further suggestive of a role for MmpL3 in the coordination of new cell wall deposition during cell septation and elongation. This novel aspect of the physiology of MmpL3 may contribute to the extreme vulnerability and high therapeutic potential of this transporter.