2,503 research outputs found

    River Run

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    River Run

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    Ecosystem Service Trade-offs in Coral Reefs: A Global Analysis

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    Coral reefs are biodiversity hotspots that provide humans with extractive ecosystem services like fisheries and non-extractive services like tourism. Though no studies have examined these trade-offs among these services at a global scale, there are now large, open datasets that make this possible. Using these datasets, we asked whether spatial protection and the level of protection (World Database on Protected Areas) impacted coral reef tourism value (Atlas of Ocean Wealth). We also examined whether proximity to regions of high fishing effort, defined as the top 25th percentile of the average annual effort from Global Fishing Watch, impacted tourism values. Since our data were zero-inflated, we used a two-step modeling approach for statistical analysis, examining predictors of tourism presence/absence then predictors of tourism value magnitude. We found that protected coral reefs are more likely to have a tourism value than those that are not. Among reefs with tourism value, protected areas had a higher average value than unprotected areas. In addition, the level of protection influenced the likelihood and magnitude of tourism value, though in some instances in unexpected ways, possibly due to restrictions on tourism in strongly protected reefs. Coral reefs in closer proximity to high fishing effort had a lower chance of having tourism value, but in areas that did have tourism value, areas closer to high fishing effort had a higher average value. Using large, global datasets of ecosystem services, our study informs management trade-offs in coral reef ecosystems

    Method development through statistical design for the dependence of viscosity for solutions of carboxymethylcellulose on temperature, concentration, and dilution.

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    Statistical method development is useful when expense, quantity of material, or time is limited, as experiment numbers are significantly reduced. The purpose of this study was to create a statistical model that explains the relationship between viscosity, temperature, concentration, and dilution due to bodily fluids in a pharmaceutical context of carboxymethylcellulose (CMC) solutions. The Graeco-Latin square design was employed to chose data points and Minitab® statistical software was used for data analysis. It was found in this model that concentration and dilution have the greatest effect on viscosity, while temperature has a lesser effect. It was also found that there was some interaction between the variables (temperature, concentration, and dilution) chosen for this study

    The Restoration of Language in Middle-earth

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    “An analysis of how Tolkien uses language from the critical stance of chaos theory.

    Ground-based searches for interstellar H_(2)D^+

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    We present ground-based searches for the 1_(10) - 1_(11) line of interstellar H_(2)D^(+) at 372 GHz which are more sensitive than those obtained from the Kuiper Airborne Observatory by factors of 3-4 for extended sources and by more than two orders of magnitude for compact sources. The line was not detected in a variety of interstellar clouds, including NGC 2264 toward which a possible detection had been suggested previously. The inferred H_(2)D^(+) abundance limits of 10^(-10) - 10^(-11) are still consistent with, but approach the abundances predicted by chemical models. Simultaneous observations of the DCO^(+) 3-2 and N_(2)H^(+) 4-3 lines have been used to place additional limits on the H_(3)^(+) abundance, and suggest 10^(-11) < x(H_(3)^(+))< 10^(-9). The N_(2)H^(+) data also indicate that for NGC 2264, but perhaps not for the other sources, gas-phase N_2 contains a substantial fraction of the available nitrogen in the cloud

    Interstellar H^+_3: possible detection of the 1_(10)→1_(11) transition of H_2D^+

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    An interstellar line has been detected in emission at the expected submillimeter wavelength of the 1_(10)→1_(11) transition of H_(2)D^+, the deuterated version of the primary ion (H^(+)_(3)) in the favored ion-molecule reaction scheme for interstellar gas phase chemistry. The strength of the line is in approximate agreement with the theoretically anticipated H_(2)D^+ abundance

    Far infrared maps of the ridge between OMC-1 and OMC-2

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    Dust continuum emission from a 6 ft x 20 ft region surrounding OMC-1 and OMC-2 were mapped at 55 and 125 microns with 4 ft resolution. The dominant features of the maps are a strong peak at OMC-1 and a ridge of lower surface brightness between OMC-1 and OMC-2. Along the ridge the infrared flux densities and the color temperature decreases smoothly from OMC-1 to OMC-2. OMC-1 is heated primarily by several optical and infrared stars situated within or just at the boundary of the cloud. At the region of minimum column density between OMC-1 and OMC-2 the nearby B0.5 V star NU Ori may contribute significantly to the dust heating. Near OMC-2 dust column densities are large enough so that, in addition to the OMC-2 infrared cluster, the nonlocal infrared sources associated with OMC-1 and NU Ori can contribute to the heating

    NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 28: The technical communication practices of Russian and US aerospace engineers and scientists

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    As part of Phase 4 of the NASA/DoD Aerospace Knowledge Diffusion Research Project, two studies were conducted that investigated the technical communication practices of Russian and U.S. aerospace engineers and scientists. Both studies had the same five objectives: first, to solicit the opinions of aerospace engineers and scientists regarding the importance of technical communication to their professions; second, to determine the use and production of technical communication by aerospace engineers and scientists; third, to seek their views about the appropriate content of the undergraduate course in technical communication; fourth, to determine aerospace engineers' and scientists' use of libraries, technical information centers, and on-line databases; and fifth, to determine the use and importance of computer and information technology to them. A self administered questionnaire was distributed to Russian aerospace engineers and scientists at the Central Aero-Hydrodynamic Institute (TsAGI) and to their U.S. counterparts at the NASA Ames Research Center and the NASA Langley Research Center. The completion rates for the Russian and U.S. surveys were 64 and 61 percent, respectively. Responses of the Russian and U.S. participants to selected questions are presented in this paper
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