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Elsah, IL, United States

Principia College is a private liberal arts college in Elsah, Illinois, United States. A four-year coeducational institution, the college was founded in 1912 by Mary Kimball Morgan, and its stated purpose is "to serve the Cause of Christian Science." According to the college, it has no affiliation with the Church of Christ, Scientist, but "the practice of Christian Science is the cornerstone of campus life." Students and staff are practicing Christian Scientists.Principia sits on bluffs overlooking the Mississippi River between Alton and Grafton in the Metro East region of Southern Illinois, thirty miles north of St. Louis. The 2,500 acres acre campus is a designated National Historic Landmark by the United States Department of the Interior Wikipedia.

Margriter S.C.,National Park Service | Bruland G.L.,Principia College | Kudray G.M.,National Park Service | Lepczyk C.A.,University of Hawaii at Manoa
Landscape Ecology | Year: 2014

Although wetland condition assessment procedures have been developed, validated, and calibrated in the continental United States, they have not yet been fully developed or field-tested for wetlands in Hawai'i. In order to address the need for comprehensive assessment methods for Hawaiian coastal wetlands, our research compared three indicators of landscape condition (landscape development intensity, road density, and forest cover) with wetland condition as measured by rapid assessment methods (RAM) and detailed field data collected on soil and water quality. We predicted that wetlands located in the least developed landscapes would have more nutrient rich soils, yet lower nutrient levels in the surface water, and would receive the highest rapid assessment scores. The hypotheses of our study were generally supported. However, while the correlations between landscape variables and δ15N isotopes and CRAM scores were relatively strong, the correlations between the landscape indicators and the other Level II and III field indicators were not very strong. These results suggest that further calibration and refinement of metrics is needed in order to more accurately assess the condition of Hawaiian coastal wetlands. A more detailed land use map, in addition to more comprehensive assessments of wetland water quality and biotic integrity would likely improve the relationships between indicators of landscape condition and wetland condition. Nonetheless, our research demonstrated that landscape analysis at larger scales (1,000 m buffers and watersheds) could provide managers with valuable information on how regional stressors may be affecting wetland water quality (measured as δ15N in plant tissue) as well as overall wetland condition (RAM scores). © 2014 Springer Science+Business Media Dordrecht. Source

Jantz L.A.,National Oceanic and Atmospheric Administration | Morishige C.L.,National Oceanic and Atmospheric Administration | Morishige C.L.,M Group Inc. | Bruland G.L.,Principia College | Lepczyk C.A.,University of Hawaii at Manoa
Marine Pollution Bulletin | Year: 2013

Plastic marine debris affects species on most trophic levels, including pelagic fish. While plastic debris ingestion has been investigated in planktivorous fish in the North Pacific Ocean, little knowledge exists on piscivorous fish. The objectives of this study were to determine the frequency of occurrence and the composition of ingested plastic marine debris in longnose lancetfish (Alepisaurus ferox), a piscivorous fish species captured in the Hawaii-based pelagic longline fishery. Nearly a quarter (47 of 192) of A. ferox sampled contained plastic marine debris, primarily in the form of plastic fragments (51.9%). No relationship existed between size (silhouette area) or amount of plastic marine debris ingested and morphometrics of A. ferox. Although A. ferox are not consumed by humans, they are common prey for fish commercially harvested for human consumption. Further research is needed to determine residence time of ingested plastic marine debris and behavior of toxins associated with plastic debris. © 2013. Source

Zellem R.T.,University of Arizona | Lewis N.K.,Massachusetts Institute of Technology | Knutson H.A.,MC 170 25 | Griffith C.A.,University of Arizona | And 9 more authors.
Astrophysical Journal | Year: 2014

The hot Jupiter HD 209458b is particularly amenable to detailed study as it is among the brightest transiting exoplanet systems currently known (V-mag = 7.65; K-mag = 6.308) and has a large planet-to-star contrast ratio. HD 209458b is predicted to be in synchronous rotation about its host star with a hot spot that is shifted eastward of the substellar point by superrotating equatorial winds. Here we present the first full-orbit observations of HD 209458b, in which its 4.5 μm emission was recorded with Spitzer/IRAC. Our study revises the previous 4.5 μm measurement of HD 209458b's secondary eclipse emission downward by 35% to , changing our interpretation of the properties of its dayside atmosphere. We find that the hot spot on the planet's dayside is shifted eastward of the substellar point by 40.°9 ± 6.°0, in agreement with circulation models predicting equatorial superrotation. HD 209458b's dayside (T bright = 1499 ± 15 K) and nightside (T bright = 972 ± 44 K) emission indicate a day-to-night brightness temperature contrast smaller than that observed for more highly irradiated exoplanets, suggesting that the day-to-night temperature contrast may be partially a function of the incident stellar radiation. The observed phase curve shape deviates modestly from global circulation model predictions potentially due to disequilibrium chemistry or deficiencies in the current hot CH4 line lists used in these models. Observations of the phase curve at additional wavelengths are needed in order to determine the possible presence and spatial extent of a dayside temperature inversion, as well as to improve our overall understanding of this planet's atmospheric circulation. © 2014. The American Astronomical Society. All rights reserved.. Source

Knutson H.A.,California Institute of Technology | Lewis N.,University of Arizona | Fortney J.J.,University of California at Santa Cruz | Burrows A.,Princeton University | And 10 more authors.
Astrophysical Journal | Year: 2012

We present new, full-orbit observations of the infrared phase variations of the canonical hot Jupiter HD 189733b obtained in the 3.6 and 4.5 μm bands using the Spitzer Space Telescope. When combined with previous phase curve observations at 8.0 and 24 μm, these data allow us to characterize the exoplanet's emission spectrum as a function of planetary longitude and to search for local variations in its vertical thermal profile and atmospheric composition. We utilize an improved method for removing the effects of intrapixel sensitivity variations and robustly extracting phase curve signals from these data, and we calculate our best-fit parameters and uncertainties using a wavelet-based Markov Chain Monte Carlo analysis that accounts for the presence of time-correlated noise in our data. We measure a phase curve amplitude of 0.1242% ± 0.0061% in the 3.6 μm band and 0.0982% ± 0.0089% in the 4.5 μm band, corresponding to brightness temperature contrasts of 503 ± 21K and 264 ± 24K, respectively. We find that the times of minimum and maximum flux occur several hours earlier than predicted for an atmosphere in radiative equilibrium, consistent with the eastward advection of gas by an equatorial super-rotating jet. The locations of the flux minima in our new data differ from our previous observations at 8 μm, and we present new evidence indicating that the flux minimum observed in the 8 μm is likely caused by an overshooting effect in the 8 μm array. We obtain improved estimates for HD 189733b's dayside planet-star flux ratio of 0.1466% ± 0.0040% in the 3.6 μm band and 0.1787% ± 0.0038% in the 4.5 μm band, corresponding to brightness temperatures of 1328 ± 11K and 1192 ± 9K, respectively; these are the most accurate secondary eclipse depths obtained to date for an extrasolar planet. We compare our new dayside and nightside spectra for HD 189733b to the predictions of one-dimensional radiative transfer models from Burrows etal. and conclude that fits to this planet's dayside spectrum provide a reasonably accurate estimate of the amount of energy transported to the night side. Our 3.6 and 4.5 μm phase curves are generally in good agreement with the predictions of general circulation models for this planet from Showman etal., although we require either excess drag or slower rotation rates in order to match the locations of the measured maxima and minima in the 4.5, 8.0, and 24 μm bands. We find that HD 189733b's 4.5 μm nightside flux is 3.3σ smaller than predicted by these models, which assume that the chemistry is in local thermal equilibrium. We conclude that this discrepancy is best explained by vertical mixing, which should lead to an excess of CO and correspondingly enhanced 4.5 μm absorption in this region. This result is consistent with our constraints on the planet's transmission spectrum, which also suggest excess absorption in the 4.5 μm band at the day-night terminator. © 2012. The American Astronomical Society. All rights reserved. Source

Taylor D.L.,University of Alaska Fairbanks | Herriott I.C.,U.S. Geological Survey | Stone K.E.,U.S. Geological Survey | Mcfarland J.W.,U.S. Geological Survey | And 2 more authors.
Canadian Journal of Forest Research | Year: 2010

This paper outlines molecular analyses of soil fungi within the Bonanza Creek Long Term Ecological Research program. We examined community structure in three studies in mixed upland, black spruce (Picea mariana (Mill.) BSP), and white spruce (Picea glauca (Moench) Voss) forests and examined taxa involved in cellulose degradation at one upland site. We found that soil horizon was the factor by which fungal communities were most strongly structured and that predictable turnover in upland fungal species occurred through succession. Communities from consecutive summers were not significantly different, indicating that interannual variation was small in relation to differences between forest types and soil horizons, yet the community at a seasonal study site underwent significant changes within a year. In each study, mycorrhizal fungi dominated the community. Fungi rather than bacteria appeared to dominate [13C]cellulose degradation,with strongest growth in taxa that were not dominant members of the untreated community, including members of the genus Sebacina. Overall, our results point to considerable interannual resilience juxtaposed with narrow niche partitioning and the capacity of individual taxa in these hyperdiverse communities to respond strongly to resource inputs and changes in other abiotic environmental parameters such as temperature. Our data double the cumulative total of fungal sequences in GenBank and together achieve a better picture of fungal communities here than for any other ecosystem on earth at this time. Source

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