Dynamic mechanical and melt rheological properties of ethylene copolymers and ionomers/

Polymer Science and EngineeringDoctor of Philosophy (PhD

Cellular Determinants of Coronavirus Entry Routes

Coronaviruses (CoVs) represent some of the greatest modern threats to global health. CoVs are zoonotic viruses that generally cause respiratory or enteric infections. The ability of CoVs to move between species and into human populations ensures that CoVs will remain important and dangerous pathogens. Therefore, understanding how CoVs infect different hosts is vital to human health. CoVs are enveloped and must undergo fusion of viral and host membranes to initiate infection. Viral glycoproteins, called Spike (S) proteins, are responsible for host cell binding and carrying out the membrane fusion reaction. S proteins store energy in their folded, pre-fusion conformation that is released upon interaction with host cell factors. These host cell factors include cellular receptors, which bind to S proteins and change their conformation, and host proteases, which cleave S proteins which releases the stored energy and catalyzes fusion. Thus, to successfully infect target cells, CoV S proteins must encounter cellular receptors and proteases at the same time and place. Our goal was to determine where on the cell surface, CoVs encounter receptors and proteases. Using biochemical isolation of cellular membranes, we showed that these entry factors are concentrated in small, ordered regions of the membrane that are also rich in scaffolding proteins called tetraspanins. These isolated membrane fractions were capable of cleaving CoV S proteins in a manner similar to trypsin, indicating the presence of active proteases within these regions. Furthermore, we used CoV infection and pseudovirus transduction to determine that CoVs reside in or near these tetraspanin- enriched membrane microdomains (TEMs) following receptor binding and that antibody crosslinking of tetraspanins inhibits CoV entry. While our results suggested that TEMs function as CoV entry portals, the identity of tetraspanin interactions with CoV entry factors was not clear. We used CRISPR/Cas9 knockout of the tetraspanins CD9 and CD81 and determined the effect on CoV entry. We found that CD9-deficient cells were resistant to infection by MERS and 229E CoVs but were still susceptible to infection by SARS and MHV CoVs. The receptors for MERS and 229E, but not SARS or MHV, were absent from isolated TEM membrane fractions in CD9 deficient cells. These results indicated that CD9 acts as the specific tetraspanin partner for MERS and 229E receptors. The presence of CD9 in target cells also influenced the route of entry that MERS viruses utilized. Without CD9, MERS infection was dependent on endocytosis and cathepsin activation of S proteins. In cells replete with CD9, MERS entry was more rapid and more dependent on host cell transmembrane proteases

Determination of changes in pebble sphericity and roundness in a downstream direction in Clear Creek, Fairfield -- Hocking Counties, Ohio

Evaluation of the data obtained is used to show the relationships between roundness and sphericity of pebbles and the distance downstream these pebbles were collected, with lithology of the pebbles and glacial boundaries crossed by the stream taken into account. Evaluations are based on data taken from sixteen locations on Clear Creek and one location on the Hocking River in Fairfield-Hocking Counties, Ohio.No embarg

The Effects of Energy Drink Consumption on Cognitive and Physical Performance in Elite League of Legends Players.

To examine the cognitive and physical changes associated with consuming an energy drink concurrent to video gaming, we examined a convenience sample of nine elite League of Legends (LoL) e-sport players (21 ± 2 y, BMI 25.6 ± 3.4 kg/m2) consuming an energy drink (ReloadTM) or placebo (Placebo) in a randomized, double-blind, placebo-controlled cross-over trial. Participants completed the same test battery prior to treatment consumption and after playing each of three competitive LoL games. Primary outcomes included measures of attention (Erikson Flanker Test), reaction time (Go/No-Go test) and working memory (n-back test). Secondary outcomes examined fatigue (hand grip strength and finger tap speed). Statistical analysis was performed by repeated-measures analysis of variance (RM-ANOVA) and reported as the mean (standard deviation [SD]) or mean change (95% confidence interval [CI]). Participants reported sleeping 8.1 (1.2) h/night, playing LoL 10.3 (2.1) h/d, playing other video games 1.8 (2.8) h/d, and exercising 4.2 (1.7) times per week. Overall, we observed no significant time, group, or group-by-time interactions for any measured performance index with the exception of a significant improvement for the n-back test, where the Reload group demonstrated a significant within-group improvement: Reload [-171 ms (95% CI, -327.91, -14.09), p < 0.004], Placebo [-92 ms (95% CI, -213.63, 29.63)]. However, no between-group differences were noted (38.50 ms, 95% CI, -141.89, 64.89, p = 0.803). Our findings suggest that elite eSport athletes do not demonstrate a mental or physical improvement in performance relative to the treatment supplement or indices measured in this study

Ecological Drivers of Song Evolution in Birds: Disentangling the Effects of Habitat and Morphology

Environmental differences influence the evolutionary divergence of mating signals through selection acting either directly on signal transmission (“sensory drive”) or because morphological adaptation to different foraging niches causes divergence in “magic traits” associated with signal production, thus indirectly driving signal evolution. Sensory drive and magic traits both contribute to variation in signal structure, yet we have limited understanding of the relative role of these direct and indirect processes during signal evolution. Using phylogenetic analyses across 276 species of ovenbirds (Aves: Furnariidae), we compared the extent to which song evolution was related to the direct influence of habitat characteristics and the indirect effect of body size and beak size, two potential magic traits in birds. We find that indirect ecological selection, via diversification in putative magic traits, explains variation in temporal, spectral, and performance features of song. Body size influences song frequency, whereas beak size limits temporal and performance components of song. In comparison, direct ecological selection has weaker and more limited effects on song structure. Our results illustrate the importance of considering multiple deterministic processes in the evolution of mating signals

Selective preservation of protein kinase C-ζ in the chemoprevention of azoxymethane-induced colonic tumors by piroxicam

AbstractWhile nonsteroidal anti-inflammatory drugs have been shown to exert preventive effects against the development of colonic tumors in humans and in chemically-induced tumors in animal models, the mechanism(s) involved in this phenomenon is unclear. We have recently demonstrated that one such agent, piroxicam, when supplemented (75 ppm) in the diets of rats administered azoxymethane, reduced the incidence of rats bearing tumors. To date, the effects of piroxicam on protein kinase C, a family of serine/threonine kinases which may be intimately involved in the colonic malignant transformation process, have not been examined. It was, therefore, of interest to determine whether piroxicam altered the expression of one or more isoforms of this kinase in these tumors. The present studies demonstrate that dietary piroxicam selectively preserved the expression of protein kinase C-ζ in azoxymethane-induced tumors; suggesting that this is at least one mechanism involved in this agent's chemopreventive actions in this organ

The profiling of diet and physical activity in reproductive age women and their association with body mass index

Pre-pregnancy, pregnancy and postpartum are critical life stages associated with higher weight gain and obesity risk. Among these women, the sociodemographic groups at highest risk for suboptimal lifestyle behaviours and core lifestyle components associated with excess adiposity are unclear. This study sought to identify subgroups of women meeting diet/physical activity (PA) recommendations in relation to sociodemographics and assess diet/PA components associated with body mass index (BMI) across these life stages. Cross-sectional data (Australian National Nutrition and Physical Activity Survey 2011-2012) were analysed for pre-pregnancy, pregnant and postpartum women. The majority (63-95%) of women did not meet dietary or PA recommendations at all life stages. Core and discretionary food intake differed by sociodemographic factors. In pre-pregnant women, BMI was inversely associated with higher whole grain intake (β = -1.58, 95% CI -2.96, -0.21; = 0.025) and energy from alcohol (β = -0.08, -0.14, -0.005; = 0.035). In postpartum women, BMI was inversely associated with increased fibre (β = -0.06, 95% CI -0.11, -0.004; = 0.034) and PA (β = -0.002, 95% CI -0.004, -0.001; = 0.013). This highlights the need for targeting whole grains, fibre and PA to prevent obesity across life stages, addressing those most socioeconomically disadvantaged

Predictors of failed attendances in a multi-specialty outpatient centre using electronic databases.

BACKGROUND: Failure to keep outpatient medical appointments results in inefficiencies and costs. The objective of this study is to show the factors in an existing electronic database that affect failed appointments and to develop a predictive probability model to increase the effectiveness of interventions. METHODS: A retrospective study was conducted on outpatient clinic attendances at Tan Tock Seng Hospital, Singapore from 2000 to 2004. 22864 patients were randomly sampled for analysis. The outcome measure was failed outpatient appointments according to each patient's latest appointment. RESULTS: Failures comprised of 21% of all appointments and 39% when using the patients' latest appointment. Using odds ratios from the mutliple logistic regression analysis, age group (0.75 to 0.84 for groups above 40 years compared to below 20 years), race (1.48 for Malays, 1.61 for Indians compared to Chinese), days from scheduling to appointment (2.38 for more than 21 days compared to less than 7 days), previous failed appointments (1.79 for more than 60% failures and 4.38 for no previous appointments, compared with less than 20% failures), provision of cell phone number (0.10 for providing numbers compared to otherwise) and distance from hospital (1.14 for more than 14 km compared to less than 6 km) were significantly associated with failed appointments. The predicted probability model's diagnostic accuracy to predict failures is more than 80%. CONCLUSION: A few key variables have shown to adequately account for and predict failed appointments using existing electronic databases. These can be used to develop integrative technological solutions in the outpatient clinic