368 research outputs found
Ballistic Flash Characterization: Penetration and Back-face Flash
The Air Force is extremely concerned with the safety of its people, especially those who are flying aircraft. Aircrew members flying combat missions are concerned with the chance that a fragment from an exploding threat device may penetrate into the airframe to possibly ignite a fire onboard the aircraft. One concern for vulnerability revolves around a flash that may occur when a projectile strikes and penetrates an aircraft\u27s fuselage. When certain fired rounds strike the airframe, they break into fragments called spall. Spall and other fragmentation from an impact often gain enough thermal energy to oxidize the materials involved. This oxidation causes a flash. To help negate these incidents, analysts must be able to predict the flash that can occur when a projectile strikes an aircraft. This research directly continues AFIT work for the 46th Test Group, Survivability Analysis Flight, by examining models to predict the likelihood of penetration of a fragment fired at a target. Empirical live-fire fragment test data are used to create an empirical model of a flash event. The resulting model provides an initial back-face flash modeling capability that can be implemented in joint survivability analysis models
Resilience and stability of a pelagic marine ecosystem
The accelerating loss of biodiversity and ecosystem services worldwide has accentuated a long-standing debate on the role of diversity in stabilizing ecological communities and has given rise to a field of research on biodiversity and ecosystem functioning (BEF). Although broad consensus has been reached regarding the positive BEF relationship, a number of important challenges remain unanswered. These primarily concern the underlying mechanisms by which diversity increases resilience and community stability, particularly the relative importance of statistical averaging and functional complementarity. Our understanding of these mechanisms relies heavily on theoretical and experimental studies, yet the degree to which theory adequately explains the dynamics and stability of natural ecosystems is largely unknown, especially in marine ecosystems. Using modelling and a unique 60-year dataset covering multiple trophic levels, we show that the pronounced multi-decadal variability of the Southern California Current System (SCCS) does not represent fundamental changes in ecosystem functioning, but a linear response to key environmental drivers channelled through bottom-up and physical control. Furthermore, we show strong temporal asynchrony between key species or functional groups within multiple trophic levels caused by opposite responses to these drivers. We argue that functional complementarity is the primary mechanism reducing community variability and promoting resilience and stability in the SCCS
ROCK Inhibitor Increases Proacinar Cells in Adult Salivary Gland Organoids
Salisphere-derived adult epithelial cells have been used to improve saliva production of irradiated mouse salivary glands. Importantly, optimization of the cellular composition of salispheres could improve their regenerative capabilities. The Rho Kinase (ROCK) inhibitor, Y27632, has been used to increase the proliferation and reduce apoptosis of progenitor cells grown in vitro. In this study, we investigated whether Y27632 could be used to improve expansion of adult submandibular salivary epithelial progenitor cells or to affect their differentiation potential in different media contexts. Application of Y27632 in medium used previously to grow salispheres promoted expansion of Kit+ and Mist1+ cells, while in simple serum-containing medium Y27632 increased the number of cells that expressed the K5 basal progenitor marker. Salispheres derived from Mist1CreERT2; R26TdTomato mice grown in salisphere media with Y27632 included Mist1-derived cells. When these salispheres were incorporated into 3D organoids, inclusion of Y27632 in the salisphere stage increased the contribution of Mist1-derived cells expressing the proacinar/acinar marker, Aquaporin 5 (AQP5), in response to FGF2-dependent mesenchymal signals. Optimization of the cellular composition of salispheres and organoids can be used to improve the application of adult salivary progenitor cells in regenerative medicine strategies
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Even bad clients deserve quality advertising: using the templates creative ideation technique to overcome the limitations of client quality
This paper examines how ideation techniques like the Templates method (Goldenberg, Mazursky and Solomon 1999) can overcome the limitations of poor client quality and low intrinsic motivation so to produce highly creative outcomes. We present a 2 X 4 experiment manipulating client quality and ideation techniques respectively, involving 207 working creatives in major agencies in South Africa and Nigeria. Each creative was asked to develop two ads in response to a hypothetical brief. Creatives’ self-reports were analysed using ANOVA and showed not all ideation techniques work in all client situations. The Unification template overcomes motivational limitations in situations of a poor quality client. Alternatively, the Metaphor template works well on average, little known client. The Extreme consequences template does not work well in either situation
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The role of consumer insight in creative advertising development: essential aid or cognitive bias?
Advertising professionals praise the role of consumer insight in solving advertising problems creatively. Marketing clients and account planners claim to use insight to inject the necessary strategy into a campaign, building a creative platform upon which a brand connects with consumers. Although insight is widely seen as an invaluable aid, another perspective is that insight can create mental set fixation, a cognitive bias that reinforces only limited perspectives on a problem, thus inhibiting creativity. This study examines whether strong, weak or no primed insight conditions help or hinder professional creatives to develop highly creative advertising ideas, testing across two media, print and television. Self-assessments of creatives show that they see insight as compensating for low domain knowledge. However, assessments by objective judges, who are also creatives, show insight works by compensating for low intrinsic motivation. Although we show consumer insight can improve the quality of creative ideas, it should be carefully managed to produce consistently high-quality creative work
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How does consumer insight support the leap to a creative idea inside the creative process: shifting the advertising appeal from functional to emotional
Account planners identify and articulate a key strategic resource, consumer insight, from which creative ideation is said to "leap." We argue that insight gives creatives a license to develop emotional advertising that connects with consumers. An experiment is performed using 60 working creatives who developed creative advertising ideas under three treatment conditions; a strong insight, a weak one and a no primed insight control. Although the knowledge domains creatives use in executions appear similar across the three conditions, providing insight leads to more emotional appeals rather than functional ones, especially for strong insight
The impact of deep-sea fisheries and implementation of the UNGA Resolutions 61/105 and 64/72. Report of an international scientific workshop
The scientific workshop to review fisheries management, held in Lisbon in May 2011, brought together 22 scientists and fisheries experts from around the world to consider the United Nations General Assembly (UNGA) resolutions on high seas bottom fisheries: what progress has been made and what the outstanding issues are. This report summarises the workshop conclusions, identifying examples of good practice and making recommendations in areas where it was agreed that the current management measures fall short of their target
Epipelagic and mesopelagic fishes in the southern California Current System: Ecological interactions and oceanographic influences on their abundance
We use zooplankton and ichthyoplankton data from the~60-year CalCOFI time series to examine relationships of mesopelagic (i.e. midwater) fishes in the California Current System with midwater predators, potential competitors (epipelagic planktivorous fishes) and zooplankton prey, within the context of local and basin-scale oceanography. Equilibrium-based near-steady state models and the "wasp-waist" paradigm for eastern boundary currents predict tightly-coupled trophic interactions, with negative correlations between the abundance of planktivorous competitors and between dominant planktivores and their prey. Testing these hypotheses with the CalCOFI time series, we found them to be generally invalid. Potential competitors within the mesopelagic community (planktivorous vertical migrators (VMs) and non-migrators (NMs)) were highly positively correlated, as were these groups with the mesopelagic piscivores (e.g. dragonfishes) that prey on them. In addition, the abundance of VMs was mostly positively correlated with that of epipelagic planktivores, such as anchovy, mackerels and hake. The VMs and epipelagic planktivores were negatively correlated with key potential planktonic prey groups, indicating a lack of bottom-up forcing. However, neither do these negative correlations appear to signify top-down forcing, since they seem to be mediated through correlations with key environmental drivers, such as the Pacific Decadal Oscillation (PDO), sea surface temperature, and the relative strength of the California Current. We suggest that the web of correlations linking key meso-and epipelagic planktivores, their predators and prey is mediated through common links with basin-scale oceanographic drivers, such as the PDO and ENSO cycles. Thus, the abundance of mesopelagic fishes in the California Current is closely tied to variation in the oxygen minimum zone, whose dynamics have been linked to the PDO. The PDO and other drivers are also linked to the transport of the California Current System, which influences the abundance of many dominant taxa off southern California that have broad biogeographic distributions linked to water masses that extend to the north (Transition Zone/sub-Arctic faunas) or the south (tropical/subtropical faunas)
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