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Neither Genius nor Fudge: Edgar Allan Poe and Eureka
Stott, G. St. John
452o F : Revista de Teoría de la Literatura y Literatura Comparada , 2009,
Abstract: "Eureka" (1848) has been taken at face value as an expanded version of a lecture on cosmology that Poe gave earlier the same year. However, its seriousness as a work of science should be questioned. Its treatment of themes found in other works by Poe shows the author’s unconcern for consistency, and the text unlikely to have resulted from a serious engagement with scientific argument. Instead it should be approached as a hoax: an attempt to reveal the gullibility of its readers. Poe’s hoaxes relied for their effect on the trust created in readers by their recognition of generic conventions, and Eureka exploited and ridiculed public trust in cosmological lecturers such as John Bovee Dods.
The spring 2011 final stratospheric warming above Eureka: anomalous dynamics and chemistry
C. Adams, K. Strong, X. Zhao, A. E. Bourassa, W. H. Daffer, D. Degenstein, J. R. Drummond, E. E. Farahani, A. Fraser, N. D. Lloyd, G. L. Manney, C. A. McLinden, M. Rex, C. Roth, S. E. Strahan, K. A. Walker,I. Wohltmann
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2013,
Abstract: In spring 2011, the Arctic polar vortex was stronger than in any other year on record. As the polar vortex started to break up in April, ozone and NO2 columns were measured with UV-visible spectrometers above the Polar Environment Atmospheric Research Laboratory (PEARL) in Eureka, Canada (80.05° N, 86.42° W) using the differential optical absorption spectroscopy (DOAS) technique. These ground-based column measurements were complemented by Ozone Monitoring Instrument (OMI) and Optical Spectrograph and Infra-Red Imager System (OSIRIS) satellite measurements, Global Modeling Initiative (GMI) simulations, and meteorological quantities. On 8 April 2011, NO2 columns above PEARL from the DOAS, OMI, and GMI datasets were approximately twice as large as in previous years. On this day, temperatures and ozone volume mixing ratios above Eureka were high, suggesting enhanced chemical production of NO2 from NO. Additionally, GMI NOx (NO + NO2) and N2O fields suggest that downward transport along the vortex edge and horizontal transport from lower latitudes also contributed to the enhanced NO2. The anticyclone that transported lower-latitude NOx above PEARL became frozen-in and persisted in dynamical and GMI N2O fields until the end of the measurement period on 31 May 2011. Ozone isolated within this frozen-in anticyclone (FrIAC) in the middle stratosphere was lost due to reactions with the enhanced NOx. Below the FrIAC (from the tropopause to 700 K), NOx driven ozone loss above Eureka was larger than in previous years, according to GMI monthly average ozone loss rates. Using the passive tracer technique, with passive ozone profiles from the Lagrangian Chemistry and Transport Model, ATLAS, ozone losses since 1 December 2010 were calculated at 600 K. In the air mass that was above Eureka on 20 May 2011, ozone losses reached 4.2 parts per million by volume (ppmv) (58%) and 4.4 ppmv (61%), when calculated using GMI and OSIRIS ozone profiles, respectively. This gas-phase ozone loss led to a more rapid decrease in ozone column amounts above Eureka in April/May 2011 compared with previous years. Ground-based, OMI, and GMI ozone total columns all decreased by more than 100 DU from 15 April to 20 May. Two lows in the ozone columns were also investigated and were attributed to a vortex remnant passing above Eureka at ~500 K on 12/13 May and an ozone mini-hole on 22/23 May.
Dynamic Status of REST in the Mouse ESC Pluripotency Network  [PDF]
Sanjay K. Singh, Bethany L. Veo, Mohamedi N. Kagalwala, Weiwei Shi, Shoudan Liang, Sadhan Majumder
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0043659
Abstract: Background REST is abundantly expressed in mouse embryonic stem cells (ESCs). Many genome-wide analyses have found REST to be an integral part of the ESC pluripotency network. However, experimental systems have produced contradictory findings: (1) REST is required for the maintenance of ESC pluripotency and loss of REST causes increased expression of differentiation markers, (2) REST is not required for the maintenance of ESC pluripotency and loss of REST does not change expression of differentiation markers, and (3) REST is not required for the maintenance of ESC pluripotency but loss of REST causes decreased expression of differentiation markers. These reports highlight gaps in our knowledge of the ESC network. Methods Employing biochemical and genome-wide analyses of various culture conditions and ESC lines, we have attempted to resolve some of the discrepancies in the literature. Results We show that Rest+/? and Rest?/? AB-1 mutant ESCs, which did not exhibit a role of REST in ESC pluripotency when cultured in the presence of feeder cells, did show impaired self-renewal when compared with the parental cells under feeder-free culture conditions, but only in early passage cells. In late passage cells, both Rest+/? and Rest?/? AB-1 ESCs restored pluripotency, suggesting a passage and culture condition-dependent response. Genome-wide analysis followed by biochemical validation supported this response and further indicated that the restoration of pluripotency was associated by increased expression of the ESC pluripotency factors. E14Tg2a.4 ESCs with REST-knockdown, which earlier showed a REST-dependent pluripotency when cultured under feeder-free conditions, as well as Rest?/? AB-1 ESCs, showed no REST-dependent pluripotency when cultured in the presence of either feeder cells or laminin, indicating that extracellular matrix components can rescue REST's role in ESC pluripotency. Conclusions REST regulates ESC pluripotency in culture condition- and ESC line-dependent fashion and ESC pluripotency needs to be evaluated in a context dependent manner.
Yarkovsky-Driven Spreading of the Eureka Family of Mars Trojans  [PDF]
Matija ?uk,Apostolos A. Christou,Douglas P. Hamilton
Physics , 2014, DOI: 10.1016/j.icarus.2015.02.009
Abstract: Out of nine known stable Mars Trojans, seven appear to be members of an orbital grouping including the largest Trojan, Eureka. In order to test if this could be a genetic family, we simulated the long term evolution of a tight orbital cluster centered on Eureka. We explored two cases: cluster dispersal through planetary gravity alone over 1 Gyr, and a 1 Gyr evolution due to both gravity and the Yarkovsky effect. We find that the dispersal of the cluster in eccentricity is primarily due to dynamical chaos, while the inclinations and libration amplitudes are primarily changed by the Yarkovsky effect. Current distribution of the cluster members orbits are indicative of an initially tight orbital grouping that was affected by a negative acceleration (i.e. one against the orbital motion) consistent with the thermal Yarkovsky effect. We conclude that the cluster is a genetic family formed either in a collision or through multiple rotational fissions. The cluster's age is on the order of 1 Gyr, and its long-term orbital evolution is likely dominated by the seasonal, rather than diurnal, Yarkovsky effect. If confirmed, Gyr-scale dominance of the seasonal Yarkovsky effect may indicate suppression of the diurnal Yarkovsky drift by the related YORP effect. Further study of Mars Trojans is essential for understanding the long-term orbital and rotational dynamics of small bodies in the absence of frequent collisions.
Astronomical Sky Quality Near Eureka, in the Canadian High Arctic  [PDF]
Eric Steinbring,William Ward,James R. Drummond
Physics , 2011, DOI: 10.1086/664444
Abstract: Nighttime visible-light sky brightness and transparency are reported for the Polar Environment Research Laboratory (PEARL), located on a 610-m high ridge near the Eureka research station, on Ellesmere Island, Canada. Photometry of Polaris obtained in V band with the PEARL All Sky Imager (PASI) over two winters is supported by standard meteorological measurements and visual estimates of sky conditions from sea level. These data show that during the period of the study, October through March of 2008/09 and 2009/10, the sky near zenith had a mean surface brightness of 19.7 mag/square-arcsec when the sun was more than 12 deg below the horizon, reaching 20.7 mag/square-arcsec during astronomical darkness with no moon. Skies were without thick cloud and potentially usable for astronomy 86% of the time (extinction <2 mag). Up to 68% of the time was spectroscopic (<0.5 mag), attenuated by ice crystals, or clear with stable atmospheric transparency. Those conditions can persist for over 100 hours at a time. Further analysis suggests the sky was entirely free of ice crystals (truly photometric) 48+/-3% of the time at PEARL in winter, and that a higher elevation location nearby may be better.
Social network analysis of Eureka project partnership in Central and South-Eastern European regions
Bla?enka Divjak,Petra Peharda,Nina Begi?evi?
Journal of Information and Organizational Sciences , 2010,
Abstract: In this article we present research on the social network structure of project partnership in the Eureka network in order to understand country performance in the network. The main method used in our research is the Social Network Analysis (SNA). Research questions were set and examined on the set of the Central and South-Eastern European countries. We investigated regionally based partnerships, relation between central position in the network and country’s level of development and, finally, in order to analyze relation between number of project partners and project success, Eureka success stories were investigated as well.
Ξ hypernuclei predicted by the new interaction model ESC08  [cached]
Yamamoto Y.,Hiyama E.,Rijken Th.A.
EPJ Web of Conferences , 2010, DOI: 10.1051/epjconf/20100307007
Abstract: The features of the new interaction model ESC08 in ΛN , ΣN and ΞN channels are demonstrated by the partial wave contributions to single hyperon potentials UY (Y = Λ, Σ, Ξ ) in nuclear matter on the basis of the G-matrix theory. Ξ hypernuclei are studied with the ΞN G-matrix interactions derived from ESC08.
Unusually low ozone, HCl, and HNO3 column measurements at Eureka, Canada during winter/spring 2011
R. Lindenmaier, K. Strong, R. L. Batchelor, M. P. Chipperfield, W. H. Daffer, J. R. Drummond, T. J. Duck, H. Fast, W. Feng, P. F. Fogal, F. Kolonjari, G. L. Manney, A. Manson, C. Meek, R. L. Mittermeier, G. J. Nott, C. Perro,K. A. Walker
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2012,
Abstract: As a consequence of dynamically variable meteorological conditions, springtime Arctic ozone levels exhibit significant interannual variability in the lower stratosphere. In winter 2011, the polar vortex was strong and cold for an unusually long time. Our research site, located at Eureka, Nunavut, Canada (80.05° N, 86.42° W), was mostly inside the vortex from October 2010 until late March 2011. The Bruker 125HR Fourier transform infrared spectrometer installed at the Polar Environment Atmospheric Research Laboratory at Eureka acquired measurements from 23 February to 6 April during the 2011 Canadian Arctic Atmospheric Chemistry Experiment Validation Campaign. These measurements showed unusually low ozone, HCl, and HNO3 total columns compared to the previous 14 yr. To remove dynamical effects, we normalized these total columns by the HF total column. The normalized values of the ozone, HCl, and HNO3 total columns were smaller than those from previous years, and confirmed the occurrence of chlorine activation and chemical ozone depletion. To quantify the chemical ozone loss, a three-dimensional chemical transport model, SLIMCAT, and the passive subtraction method were used. The chemical ozone depletion was calculated as the mean percentage difference between the measured ozone and the SLIMCAT passive ozone, and was found to be 35%.
Unusually low ozone, HCl, and HNO3 column measurements at Eureka, Canada during winter/spring 2011  [PDF]
R. Lindenmaier,K. Strong,R. L. Batchelor,M. P. Chipperfield
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2012, DOI: 10.5194/acp-12-3821-2012
Abstract: As a consequence of dynamically variable meteorological conditions, springtime Arctic ozone levels exhibit significant interannual variability in the lower stratosphere. In winter 2011, the polar vortex was strong and cold for an unusually long time. Our research site, located at Eureka, Nunavut, Canada (80.05° N, 86.42° W), was mostly inside the vortex from October 2010 until late March 2011. The Bruker 125HR Fourier transform infrared spectrometer installed at the Polar Environment Atmospheric Research Laboratory at Eureka acquired measurements from 23 February to 6 April during the 2011 Canadian Arctic Atmospheric Chemistry Experiment Validation Campaign. These measurements showed unusually low ozone, HCl, and HNO3 total columns compared to the previous 14 yr. To remove dynamical effects, we normalized these total columns by the HF total column. The normalized values of the ozone, HCl, and HNO3 total columns were smaller than those from previous years, and confirmed the occurrence of chlorine activation and chemical ozone depletion. To quantify the chemical ozone loss, a three-dimensional chemical transport model, SLIMCAT, and the passive subtraction method were used. The chemical ozone depletion was calculated as the mean percentage difference between the measured ozone and the SLIMCAT passive ozone, and was found to be 35%.
Large surface radiative forcing from topographic blowing snow residuals measured in the High Arctic at Eureka
G. Lesins, L. Bourdages, T. J. Duck, J. R. Drummond, E. W. Eloranta,V. P. Walden
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2009,
Abstract: Ice crystals, also known as diamond dust, are suspended in the boundary layer air under clear sky conditions during most of the Arctic winter in Northern Canada. Occasionally ice crystal events can produce significantly thick layers with optical depths in excess of 2.0 even in the absence of liquid water clouds. Four case studies of high optical depth ice crystal events at Eureka in the Nunavut Territory of Canada during the winter of 2006/07 are presented. They show that the measured ice crystal surface infrared downward radiative forcing ranged from 8 to 36 W m 2 in the wavelength band from 5.6 to 20 μm for 532 nm optical depths ranging from 0.2 to 1.7. MODIS infrared and visible images and the operational radiosonde wind profile were used to show that these high optical depth events were caused by surface snow being blown off 600 to 800 m high mountain ridges about 20 to 30 km North-West of Eureka and advected by the winds towards Eureka as they settled towards the ground within the highly stable boundary layer. This work presents the first study that demonstrates the important role that surrounding topography plays in determining the occurrence of high optical depth ice crystal events from residual blowing snow that becomes a source of boundary layer ice crystals distinct from the classical diamond dust phenomenon.
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