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Wind turbines and invisible technology: unarticulated reasons for local opposition to wind energy
Local opposition to wind turbines stems from concerns about environmental and economic damage, as well as conflicts between rural and urban residents. This essay goes beyond these considerations to explore the often-unarticulated explanations for animosity toward this energy technology. Originally, it posits that opposition to visually obvious turbines arises from the successful history of an electric utility system that made its product largely invisible in its manufacture and physical manifestation. The existence of conspicuous turbines, however, reminds observers that power generation requires difficult choices in a technology-based society. The system’s previous achievement in hiding infrastructural elements, in other words, sometimes works ironically to spur objections to wind turbines. Receiving little historical study, the concealed features of a system’s infrastructure often influence assessments of technologies. By revealing the previously invisible, this essay, which draws on research in history, landscape architecture, geography, and psychology, therefore provides insights for social scientists and policymakers
Asynchronous communication in spectral-element and discontinuous Galerkin methods for atmospheric dynamics – a case study using the High-Order Methods Modeling Environment (HOMME-homme_dg_branch)
The scalability of computational applications on current and next-generation supercomputers is increasingly limited by the cost of inter-process communication. We implement non-blocking asynchronous communication in the High-Order Methods Modeling Environment for the time integration of the hydrostatic fluid equations using both the spectral-element and discontinuous Galerkin methods. This allows the overlap of computation with communication, effectively hiding some of the costs of communication. A novel detail about our approach is that it provides some data movement to be performed during the asynchronous communication even in the absence of other computations. This method produces significant performance and scalability gains in large-scale simulations.publishedVersio
Mapping Low-Density Intergalactic Gas: a Third Helium Lyman-alpha Forest
We present a new HST/STIS spectrum of the z=3.18 quasar PKS 1935-692 and
summarize the spectral features shortwards of 304A in the rest frame likely to
be caused by foreground HeII Lyman-alpha absorption. In accord with previous
results on two other quasars at similar redshifts, we demonstrate a correlation
with the HI Lyman-alpha forest absorption, and show that much of the helium
absorption is caused by a comparable quantity of more diffuse gas with
Omega~0.01, that is not detected in HI. The helium ionization zone around the
quasar is detected as well as a void seen in both HI and HeII. The properties
of the absorption are in broad agreement with those of the other quasars and
with models of the protogalactic gas distribution and ionization at this
redshift.Comment: 17 pages including 5 figures. As accepted for publication in The
Astronomical Journal (minor revisions
CHANGES IN RETAIL FOOD DELIVERY: SIGNALS FOR PRODUCERS, PROCESSORS AND DISTRIBUTORS
This paper contains two chapters related to changes in retail food delivery and sales. The first discusses trends in consumer demographics and lifestyles and how these continue to drive changes in the way food is prepared and delivered to consumers. Retail stores are responding with new formats: providing more ready to eat foods; more convenient store layouts; lower prices and better service in niche markets across the country. Their demands send signals up the food chain to processors and producers that alter their production and inventory decisions. Electronic information technology speeds these changes and leads to more efficient operation with, allegedly, better service for consumers. The second chapter discusses how advances in information technology affect not only the internal business operations in food firms throughout the food supply chain but also how the product flows and how businesses link their processes together. The reengineering of the food supply chain by way of an industry-wide initiative called "efficient consumer response" (ECR) is explained and analyzed for its motivations and implementation, thus far. The many facets of ECR such as product replenishment and promotion are discussed. Lessons learned from ECR include that it is possible to accommodate the coexistence of firms of various sizes and types, and that the role of trade associations in facilitating industry-wide changes is vital and impressive.Agribusiness, Industrial Organization,
Relationship Between the Foveal Avascular Zone and Foveal Pit Morphology
Purpose.To assess the relationship between foveal pit morphology and size of the foveal avascular zone (FAZ).
Methods. Forty-two subjects were recruited. Volumetric images of the macula were obtained using spectral domain optical coherence tomography. Images of the FAZ were obtained using either a modified fundus camera or an adaptive optics scanning light ophthalmoscope. Foveal pit metrics (depth, diameter, slope, volume, and area) were automatically extracted from retinal thickness data, whereas the FAZ was manually segmented by two observers to extract estimates of FAZ diameter and area.
Results. Consistent with previous reports, the authors observed significant variation in foveal pit morphology. The average foveal pit volume was 0.081 mm3 (range, 0.022 to 0.190 mm3). The size of the FAZ was also highly variable between persons, with FAZ area ranging from 0.05 to 1.05 mm2 and FAZ diameter ranging from 0.20 to 1.08 mm. FAZ area was significantly correlated with foveal pit area, depth, and volume; deeper and broader foveal pits were associated with larger FAZs.
Conclusions. Although these results are consistent with predictions from existing models of foveal development, more work is needed to confirm the developmental link between the size of the FAZ and the degree of foveal pit excavation. In addition, more work is needed to understand the relationship between these and other anatomic features of the human foveal region, including peak cone density, rod-free zone diameter, and Henle fiber layer
Masculinity, Car Culture, and Carbon Emissions
Car culture is a subculture that exists in which people value the aesthetic, cultural, or historical significance of certain vehicles, and who often use their own vehicle as a means of self expression. We assumed that car culture was a dominantly male subculture and wanted to evaluate whether gender in advertising was related to fuel efficiency. We wanted to see how each decade would differ in the terms of the number of gender targeted advertisements. We also wanted to see how fuel economies and marketing strategies changed over time. We also wanted to compare fuel economies of cars that were targeted to a specific gender audience. We based on research on the assumption that car culture in the United States is overwhelmingly male dominant. Our hypothesis was that vehicles in car culture that are predominantly advertised towards men will have lower fuel efficiency than the given CAFE standards each year. We selected twelve vehicles that have remained popular in American car culture and watched commercials for them from the 1970s to present day. Our study then coded these commercials and determined the target gender audience of each. We then found the fuel economy of each vehicle per year and were able to compare it with the set CAFE standards. Our major findings was that each vehicle selected was predominantly below the CAFE standards but they were not predominantly advertised to men. Advertising as a whole was measured to target a gender-neutral audience throughout than a specific gender. We were able to see that cars associated with car culture are generally below the CAFE standards and less fuel efficient
Loss of strumpellin in the melanocytic lineage impairs the WASH Complex but does not affect coat colour
The five-subunit WASH complex generates actin networks that participate in endocytic trafficking, migration and invasion in various cell types. Loss of one of the two subunits WASH or strumpellin in mice is lethal, but little is known about their role in mammals in vivo. We explored the role of strumpellin, which has previously been linked to hereditary spastic paraplegia, in the mouse melanocytic lineage. Strumpellin knockout in melanocytes revealed abnormal endocytic vesicle morphology but no impairment of migration in vitro or in vivo and no change in coat colour. Unexpectedly, WASH and filamentous actin could still localize to vesicles in the absence of strumpellin, although the shape and size of vesicles was altered. Blue native PAGE revealed the presence of two distinct WASH complexes, even in strumpellin knockout cells, revealing that the WASH complex can assemble and localize to endocytic compartments in cells in the absence of strumpellin
Binocular vision in amblyopia : structure, suppression and plasticity
The amblyopic visual system was once considered to be structurally monocular. However, it now evident that the capacity for binocular vision is present in many observers with amblyopia. This has led to new techniques for quantifying suppression that have provided insights into the relationship between suppression and the monocular and binocular visual deficits experienced by amblyopes. Furthermore, new treatments are emerging that directly target suppressive interactions within the visual cortex and, on the basis of initial data, appear to improve both binocular and monocular visual function, even in adults with amblyopia. The aim of this review is to provide an overview of recent studies that have investigated the structure, measurement and treatment of binocular vision in observers with strabismic, anisometropic and mixed amblyopia
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