2,017 research outputs found

    An Examination of Sport Fans’ Perceptions of the Impact of the Legalization of Sport Wagering on Their Fan Experience

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    Over the years, professional and collegiate organizations have fought attempts to increase the legalization of sport wagering. One argument presented by those in opposition is that increased legalization would negatively alter the manner in which fans and spectators follow, consume, and react to sporting events (Tuohy, 2013). The current research was designed to examine possible changes in fandom by investigating fans’ perceptions of the impact of increasing legalized sport wagering on their fan experience, interest in sport, and sport consumption. Participants (N = 580) completed a questionnaire packet assessing demographics, economic fan motivation, fandom, and perceptions of the impact of increased access to legalized sport gambling. Data and analyses indicated that expected impacts were small and generally positive (e.g., a modest increase in interest in sport and consumption) and that these effects were greatest among groups historically active in sport gambling (e.g., persons higher in economic motivation and sport fandom)

    On the cohomology of Young modules for the symmetric group

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    The main result of this paper is an application of the topology of the space Q(X)Q(X) to obtain results for the cohomology of the symmetric group on dd letters, Σd\Sigma_d, with `twisted' coefficients in various choices of Young modules and to show that these computations reduce to certain natural questions in representation theory. The authors extend classical methods for analyzing the homology of certain spaces Q(X)Q(X) with mod-pp coefficients to describe the homology \HH_{\bullet}(\Sigma_d, V^{\otimes d}) as a module for the general linear group GL(V)GL(V) over an algebraically closed field kk of characteristic pp. As a direct application, these results provide a method of reducing the computation of ExtΣd∙(Yλ,Yμ)\text{Ext}^{\bullet}_{\Sigma_{d}}(Y^{\lambda},Y^{\mu}) (where YλY^{\lambda}, YμY^{\mu} are Young modules) to a representation theoretic problem involving the determination of tensor products and decomposition numbers. In particular, in characteristic two, for many dd, a complete determination of \Hs Y^\lambda) can be found. This is the first nontrivial class of symmetric group modules where a complete description of the cohomology in all degrees can be given. For arbitrary dd the authors determine \HH^i(\Sigma_d,Y^\lambda) for i=0,1,2i=0,1,2. An interesting phenomenon is uncovered--namely a stability result reminiscent of generic cohomology for algebraic groups. For each ii the cohomology \HH^i(\Sigma_{p^ad}, Y^{p^a\lambda}) stabilizes as aa increases. The methods in this paper are also powerful enough to determine, for any pp and λ\lambda, precisely when \HH^{\bullet}(\sd,Y^\lambda)=0. Such modules with vanishing cohomology are of great interest in representation theory because their support varieties constitute the representation theoretic nucleus.Comment: Substantially revised, original stability conjecture proven for all primes. To appear, Advances in Mathematic

    Familiarity Breeds Contempt: Kangaroos Persistently Avoid Areas with Experimentally Deployed Dingo Scents

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    Background: Whether or not animals habituate to repeated exposure to predator scents may depend upon whether there are predators associated with the cues. Understanding the contexts of habituation is theoretically important and has profound implication for the application of predator-based herbivore deterrents. We repeatedly exposed a mixed mob of macropod marsupials to olfactory scents (urine, feces) from a sympatric predator (Canis lupus dingo), along with a control (water). If these predator cues were alarming, we expected that over time, some red kangaroos (Macropus rufous), western grey kangaroos (Macropus fuliginosus) and agile wallabies (Macropus agilis) would elect to not participate in cafeteria trials because the scents provided information about the riskiness of the area. Methodology/Principal Findings: We evaluated the effects of urine and feces independently and expected that urine would elicit a stronger reaction because it contains a broader class of infochemicals (pheromones, kairomones). Finally, we scored non-invasive indicators (flight and alarm stomps) to determine whether fear or altered palatability was responsible for the response. Repeated exposure reduced macropodid foraging on food associated with 40 ml of dingo urine, X = 986.75±3.97 g food remained as compared to the tap water control, X = 209.0±107.0 g (P0.5). Macropodids did not habituate to repeated exposure to predator scents, rather they avoided the entire experimental area after 10 days of trials (R2 = 83.8; P<0.001). Conclusions/Significance: Responses to urine and feces were indistinguishable; both elicited fear-based responses and deterred foraging. Despite repeated exposure to predator-related cues in the absence of a predator, macropodids persistently avoided an area of highly palatable food. Area avoidance is consistent with that observed from other species following repeated anti-predator conditioning, However, this is the first time this response has been experimentally observed among medium or large vertebrates 2 where a local response is observed spatially and an area effect is revealed over time

    Challenges and opportunities in the development of novel antimicrobial therapeutics for cystic fibrosis

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    Chronic respiratory infection is the primary driver of mortality in individuals with cystic fibrosis (CF). Existing drug screening models utilised in preclinical antimicrobial development are unable to mimic the complex CF respiratory environment. Consequently, antimicrobials showing promising activity in preclinical models often fail to translate through to clinical efficacy in people with CF. Model systems used in CF anti-infective drug discovery and development range from antimicrobial susceptibility testing in nutrient broth, through to 2D and 3D in vitro tissue culture systems and in vivo models. No single model fully recapitulates every key aspect of the CF lung. To improve the outcomes of people with CF (PwCF) it is necessary to develop a set of preclinical models that collectively recapitulate the CF respiratory environment to a high degree of accuracy. Models must be validated for their ability to mimic aspects of the CF lung and associated lung infection, through evaluation of biomarkers that can also be assessed following treatment in the clinic. This will give preclinical models greater predictive power for identification of antimicrobials with clinical efficacy. The landscape of CF is changing, with the advent of modulator therapies that correct the function of the CFTR protein, while antivirulence drugs and phage therapy are emerging alternative treatments to chronic infection. This review discusses the challenges faced in current antimicrobial development pipelines, including the advantages and disadvantages of current preclinical models and the impact of emerging treatments

    Flight Tests of a Supersonic Natural Laminar Flow Airfoil

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    A flight-test campaign of a supersonic natural laminar flow airfoil has been recently completed. The test surface was an 80-inch (203 cm) chord and 40-inch (102 cm) span article mounted on the centerline store location of an F-15B airplane (McDonnell Douglas Corporation, now The Boeing Company, Chicago, Illinois). The test article was designed with a leading edge sweep of effectively 0 deg to minimize boundary layer crossflow. The test article surface was coated with an insulating material to avoid significant heat transfer to and from the test article structure to maintain a quasi-adiabatic wall. An aircraft-mounted infrared camera system was used to determine boundary layer transition and the extent of laminar flow. The tests were flown up to Mach 2.0 and chord Reynolds numbers in excess of 30 million. The objectives of the tests were to determine the extent of laminar flow at high Reynolds numbers and to determine the sensitivity of the flow to disturbances. Both discrete (trip dots) and 2-D disturbances (forward-facing steps) were tested. A series of oblique shocks, of yet unknown origin, appeared on the surface, which generated sufficient crossflow to affect transition. Despite the unwanted crossflow, the airfoil performed well. The results indicate the sensitivity of the flow to the disturbances, which can translate into manufacturing tolerances, were similar to that of subsonic natural laminar flow wings

    Pseudomonas aeruginosa Disrupts Caenorhabditis elegans Iron Homeostasis, Causing a Hypoxic Response and Death

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    SummaryThe opportunistic pathogen Pseudomonas aeruginosa causes serious human infections, but effective treatments and the mechanisms mediating pathogenesis remain elusive. Caenorhabditis elegans shares innate immune pathways with humans, making it invaluable to investigate infection. To determine how P. aeruginosa disrupts host biology, we studied how P. aeruginosa kills C. elegans in a liquid-based pathogenesis model. We found that P. aeruginosa-mediated killing does not require quorum-sensing pathways or host colonization. A chemical genetic screen revealed that iron chelators alleviate P. aeruginosa-mediated killing. Consistent with a role for iron in P. aeruginosa pathogenesis, the bacterial siderophore pyoverdin was required for virulence and was sufficient to induce a hypoxic response and death in the absence of bacteria. Loss of the C. elegans hypoxia-inducing factor HIF-1, which regulates iron homeostasis, exacerbated P. aeruginosa pathogenesis, further linking hypoxia and killing. As pyoverdin is indispensable for virulence in mice, pyoverdin-mediated hypoxia is likely to be relevant in human pathogenesis
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