37 research outputs found
Feasibility of Electrified Propulsion for Ultra-Efficient Commercial Aircraft Final Report
MIT, Aurora Flight Sciences, and USC have collaborated to assess the feasibility of electric, hybridelectric, and turbo-electric propulsion for ultra-efficient commercial transportation. The work has drawn on the team expertise in disciplines related to aircraft design, propulsion-airframe integration, electric machines and systems, engineering system design, and optimization. A parametric trade space analysis has been carried out to assess vehicle performance across a range of transport missions and propulsion architectures to establish how electrified propulsion systems scale. An optimization approach to vehicle conceptual design modeling was taken to enable rapid multidisciplinary design space exploration and sensitivity analysis. The results of the analysis indicate vehicle aero-propulsive integration benefits enabled by electrification are required to offset the increased weight and loss associated with the electric system and achieve enhanced performance; the report describes the conceptual configurations than can offer such enhancements. The main contribution of the present work is the definition of electric vehicle design attributes for potential efficiency improvements at different scales. Based on these results, key areas for future research are identified, and extensions to the trade space analysis suitable for higher fidelity electrified commercial aircraft design and analysis have been developed
Reviving calm technology in the e-tourism context
Tourism industry practitioners should understand the controversial nature of the information and communication technology (ICT) proliferation to ensure the ICT solutions do not consume too much of their attention, thus jeopardizing consumer enjoyment of tourism services. The concept of calm technology or calm design serves this purpose. Calm design suggests that technology should quietly recede in the background and come into play with users when and if required, thus delivering and/or enhancing a desired experience. Although this concept is of relevance to e-tourism, until recently, it has never been considered within. This is where this paper contributes to knowledge as, for the first time, it introduces calm design into the e-tourism context and critically evaluates the determinants of its broader adoption within the tourism industry. It positions calm design within the e-tourism realm, discusses its implications for customer service management, supply chain management and destination management, and discloses opportunities for future research
Effect of sitagliptin on cardiovascular outcomes in type 2 diabetes
BACKGROUND: Data are lacking on the long-term effect on cardiovascular events of adding sitagliptin, a dipeptidyl peptidase 4 inhibitor, to usual care in patients with type 2 diabetes and cardiovascular disease. METHODS: In this randomized, double-blind study, we assigned 14,671 patients to add either sitagliptin or placebo to their existing therapy. Open-label use of antihyperglycemic therapy was encouraged as required, aimed at reaching individually appropriate glycemic targets in all patients. To determine whether sitagliptin was noninferior to placebo, we used a relative risk of 1.3 as the marginal upper boundary. The primary cardiovascular outcome was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for unstable angina. RESULTS: During a median follow-up of 3.0 years, there was a small difference in glycated hemoglobin levels (least-squares mean difference for sitagliptin vs. placebo, -0.29 percentage points; 95% confidence interval [CI], -0.32 to -0.27). Overall, the primary outcome occurred in 839 patients in the sitagliptin group (11.4%; 4.06 per 100 person-years) and 851 patients in the placebo group (11.6%; 4.17 per 100 person-years). Sitagliptin was noninferior to placebo for the primary composite cardiovascular outcome (hazard ratio, 0.98; 95% CI, 0.88 to 1.09; P<0.001). Rates of hospitalization for heart failure did not differ between the two groups (hazard ratio, 1.00; 95% CI, 0.83 to 1.20; P = 0.98). There were no significant between-group differences in rates of acute pancreatitis (P = 0.07) or pancreatic cancer (P = 0.32). CONCLUSIONS: Among patients with type 2 diabetes and established cardiovascular disease, adding sitagliptin to usual care did not appear to increase the risk of major adverse cardiovascular events, hospitalization for heart failure, or other adverse events
Creating Charisma Online: The Role of Digital Presence in the Formation of Religious Identity
This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Contemporary Religion on Publication Date 23-4-19, available online: https://doi.org/10.1080/13537903.2019.1585104This article investigates the construction and transmission of charisma through online channels, and its role in the formation of religious identities. Mindful of Max Weber’s observation that charisma inhabits the relationship between a leader and their followers, I argue for a critical reappraisal of the theoretical model in light of the ubiquity in the 21st century of new, virtual forms of social encounter. I focus my analysis on the Christian creationist movement in the USA, and particularly on an influential leader called Ken Ham. Using digital ethnographic methods, I show how Ham constructs charisma online, and how a virtual community forms itself around his charismatic claims. I illustrate how this virtual community intersects with offline worlds, and suggest that the theme park attractions that Ham’s organisation runs (Creation Museum, Ark Encounter) are imbued with deflected charisma by virtue of their association with his online avatar
Ion channel clustering enhances weak electric field detection by neutrophils: apparent roles of SKF96365-sensitive cation channels and myeloperoxidase trafficking in cellular responses
We have tested Galvanovskis and Sandblom’s prediction that ion channel clustering enhances weak electric field detection by cells as well as how the elicited signals couple to metabolic alterations. Electric field application was timed to coincide with certain known intracellular chemical oscillators (phase-matched conditions). Polarized, but not spherical, neutrophils labeled with anti-K v 1.3, FL-DHP, and anti-TRP1, but not anti-T-type Ca 2+ channels, displayed clusters at the lamellipodium. Resonance energy transfer experiments showed that these channel pairs were in close proximity. Dose-field sensitivity studies of channel blockers suggested that K + and Ca 2+ channels participate in field detection, as judged by enhanced oscillatory NAD(P)H amplitudes. Further studies suggested that K + channel blockers act by reducing the neutrophil’s membrane potential. Mibefradil and SKF93635, which block T-type Ca 2+ channels and SOCs, respectively, affected field detection at appropriate doses. Microfluorometry and high-speed imaging of indo-1-labeled neutrophils was used to examine Ca 2+ signaling. Electric fields enhanced Ca 2+ spike amplitude and triggered formation of a second traveling Ca 2+ wave. Mibefradil blocked Ca 2+ spikes and waves. Although 10 μM SKF96365 mimicked mibefradil, 7 μM SKF96365 specifically inhibited electric field-induced Ca 2+ signals, suggesting that one SKF96365-senstive site is influenced by electric fields. Although cells remained morphologically polarized, ion channel clusters at the lamellipodium and electric field sensitivity were inhibited by methyl-β-cyclodextrin. As a result of phase-matched electric field application in the presence of ion channel clusters, myeloperoxidase (MPO) was found to traffic to the cell surface. As MPO participates in high amplitude metabolic oscillations, this suggests a link between the signaling apparatus and metabolic changes. Furthermore, electric field effects could be blocked by MPO inhibition or removal while certain electric field effects were mimicked by the addition of MPO to untreated cells. Therefore, channel clustering plays an important role in electric field detection and downstream responses of morphologically polarized neutrophils. In addition to providing new mechanistic insights concerning electric field interactions with cells, our work suggests novel methods to remotely manipulate physiological pathways.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46726/1/249_2005_Article_1.pd
Ark Encounter as Material Apocalyptic Rhetoric: Contemporary Creationist Strategies on Board Noah\u27s Ark
The Ark Encounter (AE) is a tourist site that opened July 2016 in Kentucky, which features a replica of Noah\u27s ark. I argue that the AE is a material exemplar of the apocalyptic genre, because it makes fear of the second coming present and physical for visitors. Employing a material rhetorical analysis and participant observation, I analyze how the AE constructs an apocalyptic argument based on the topoi of authority, evil, and time. Through its material, visual, and linguistic elements, the AE promotes adherence to a specific Christian identity that includes belief in creationism