Lightning characteristics of derecho producing mesoscale convective systems     

Mace L. Bentley  John R. Franks  Katelyn R. Suranovic  Brent Barbachem  Declan Cannon  Stonie R. Cooper 《Meteorology and Atmospheric Physics》2016,128(3):303-314

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Legacies of a Contested Campus: Urban Renewal,Community Resistance,and the Origins of Gentrification in Denver     

Brian Page  Eric Ross 《Urban geography》2017,38(9):1293-1328

The postwar urban renewal experience varied among US cities according to the result of local social contests pitting those imposing their power to transform urban space against those resisting it. In this paper, we examine the role of one such contest in shaping urban renewal outcomes in Denver, using the case of the late 1960s Auraria project. The project sought to remove a poor, Hispanic neighborhood in order to build a new downtown college campus, generating community opposition from the inner city neighborhood residents, leaders of the city’s Chicano Movement, and historic preservation activists. We demonstrate how resistance actively shaped the ultimate form and character of the project, and how the legacies of this urban renewal contest extended—in unforeseen ways—beyond the immediate struggles of the time. We argue that these legacies provide the essential context for understanding planning practice, redevelopment strategies, and gentrification dynamics in the city today.  相似文献   

The effect of chromium absorption and depuration on the activities of glucose 6-phosphate dehydrogenase and aspartate amino transferase in Mytilus edulis     

David S. Page  E.S. Gilfillan  M. Clavette  J.C. Foster 《Marine environmental research》1985,17(2-4)

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Seasonal and Interannual Variability in the Distribution of Surface Nutrients and Dissolved Inorganic Carbon in the Northern North Pacific: Influence of El Niño     

Chi Shing Wong  Nathalie A. D. Waser  Yukihiro Nojiri  Wm. Keith Johnson  Frank A. Whitney  John S. C. Page  Jiye Zeng 《Journal of Oceanography》2002,58(2):227-243

The seasonal and interannual changes in surface nutrients, dissolved inorganic carbon (DIC) and total alkalinity (TA) were recorded in the North Pacific (30–54°N) from 1995 to 2001. This study focuses on the region north of the subarctic boundary (∼40°N) where there was extensive monthly coverage of surface properties. The nutrient cycles showed large interannual variations in the eastern and western subarctic gyres. In the Alaska Gyre the seasonal depletion of nitrate (ΔNO₃) increased from 8–14 μmol kg⁻¹ in 1995–1999 to 21.5 μmol kg⁻¹ in 2000. In the western subarctic the shifts were similar in amplitude but more frequent. The large ΔNO₃ levels were associated with high silicate depletions, indicating enhanced diatom production. The seasonal DIC:NO₃ drawdown ratios were elevated in the eastern and central subarctic due to calcification. In the western subarctic and the central Bering Sea calcification was significant only during 1997 and/or 1998, two El Ni?o years. Regional C/N stoichiometric molar ratios of 5.7 to 7.0 (>40°N) were determined based on the years with negligible or no calcification. The annual new production (NP_a) based on ΔNO₃ and these C/N ratios showed large interannual variations. NP_a was usually higher in the western than in the eastern subarctic. However, values of 84 gC m⁻²yr⁻¹ were found in the Alaska Gyre in 2000 which is similar to that in the most productive provinces of the northern North Pacific. There were also large increases in NP_a around the Alaska Peninsula in 1997 and 1998. Finally, the net removal of carbon by the biological pump was estimated as 0.72 Gt C yr⁻¹ in the North Pacific (>30°N). This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

The Swift gamma-ray burst GRB 050422     

A. P. Beardmore  K. L. Page  P. T. O'Brien  J. P. Osborne  S. Kobayashi  B. Zhang  D. N. Burrows  M. Capalbi  M. R. Goad  O. Godet  J. E. Hill  V. La Parola  F. Marshall  A. A. Wells 《Monthly notices of the Royal Astronomical Society》2007,374(4):1473-1478

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A hierarchical approach measures the aerial extent and concentration levels of PAH-contaminated shoreline sediments at historic industrial sites in Prince William Sound, Alaska     

Page DS  Brown JS  Boehm PD  Bence AE  Neff JM 《Marine pollution bulletin》2006,52(4):367-379

A field study was conducted in 2003 to estimate the areal distribution and concentrations of polycyclic aromatic hydrocarbons (PAH) in intertidal sediments at sites of past human and industrial activity (HA sites) in Prince William Sound (PWS), Alaska, the site of the 1989 Exxon Valdez oil spill. More than 50 HA sites, primarily in western PWS, were identified through analysis of historic records and prior field studies, and nine sites were selected for detailed surveys. The areal assessment process consisted of seven steps: (1) identify site from historic records and field surveys; (2) locate visual evidence of surface oil/tar at a site; (3) prepare a site map and lay out a sampling grid over the entire site with 10-m grid spacing; (4) excavate pits to 50 cm depth on the grid; (5) perform a field colorimetric test to estimate total PAH (TPAH) in sediments from the wall of each pit and record the results in the ranges <1 ppm; 1-10 ppm; >10 ppm TPAH; (6) expand grid size if necessary if elevated PAH levels are detected colorimetrically; (7) select 20 samples from each site for same-day shipboard PAH analysis by immunoassay (SDI RaPID PAH) and, based on these results, select sediment samples from each site for full PAH analysis in the laboratory to identify PAH sources. A total of 416 pits were dug at the nine sites. Nine acres of sediments with TPAH >2500 ppb dry wt. were mapped at the nine sites. TPAH concentrations obtained by immunochemical analysis of 181 samples from the nine sites ranged from 20 to 1,320,000 ppb (wet wt.). The contaminants are mixtures of petroleum products (2-3 ring PAH) and combustion products (4-6 ring PAH) unrelated to the 1989 Exxon Valdez oil spill. Mussels and clams collected at these sites have elevated levels of PAH that are compositionally similar to the PAH in the sediments. These findings indicate that at least a portion of the sediment PAH is bioavailable. The PAH sources at these historic industrial sites are chronic. They include relict fuel oil tanks and works located above and within the intertidal zone, with contamination at some locations extending into nearshore sub-tidal sediments. This study shows how a hierarchical approach can be used to quickly and successfully map, quantify, and subsequently, identify sources of PAH in shoreline sediments.  相似文献   

Methods and results of an automatic analysis of a complete sample of Swift-XRT observations of GRBs     

P. A. Evans  A. P. Beardmore  K. L. Page  J. P. Osborne  P. T. O'Brien  R. Willingale  R. L. C. Starling  D. N. Burrows  O. Godet  L. Vetere  J. Racusin  M. R. Goad  K. Wiersema  L. Angelini  M. Capalbi  G. Chincarini  N. Gehrels  J. A. Kennea  R. Margutti  D. C. Morris  C. J. Mountford  C. Pagani  M. Perri  P. Romano  N. Tanvir 《Monthly notices of the Royal Astronomical Society》2009,397(3):1177-1201

We present a homogeneous X-ray analysis of all 318 gamma-ray bursts detected by the X-ray telescope (XRT) on the Swift satellite up to 2008 July 23; this represents the largest sample of X-ray GRB data published to date. In Sections 2–3 , we detail the methods which the Swift -XRT team has developed to produce the enhanced positions, light curves, hardness ratios and spectra presented in this paper. Software using these methods continues to create such products for all new GRBs observed by the Swift -XRT. We also detail web-based tools allowing users to create these products for any object observed by the XRT, not just GRBs. In Sections 4–6 , we present the results of our analysis of GRBs, including probability distribution functions of the temporal and spectral properties of the sample. We demonstrate evidence for a consistent underlying behaviour which can produce a range of light-curve morphologies, and attempt to interpret this behaviour in the framework of external forward shock emission. We find several difficulties, in particular that reconciliation of our data with the forward shock model requires energy injection to continue for days to weeks.  相似文献   

Swift observations of CSS081007:030559+054715     

A.P. Beardmore  J.P. Osborne  K.L. Page  G. Schwarz  S. Starrfield  P. Hakala  J.‐U. Ness  S. Balman  R.M. Wagner 《Astronomische Nachrichten》2010,331(2):156-159

CSS081007:030559+054715 was discovered by the Catalina Real‐time Transient Survey. Optical spectroscopy revealed a multi‐peaked Hα emission line profile with radial velocities exceeding 1500 km/s, as well as strong Ne emission, suggestive of a neon nova. We monitored the source extensively with the Swift satellite, obtaining a unique dataset spanning 270 days in the soft X‐ray and UV bands. The data reveal a soft, blackbody‐like spectrum with a temperature around 55 eV (though dependent on the modelling), variable X‐ray and UV light curves with a 1.77 day period in both the X‐ray and UV bands, a longer timescale modulation of ∼ 50 days, followed by a slowly declining trend in the soft X‐ray and UV flux. We highlight the Swift observations and their implications for the SSS nature of this object (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

The evolution of the near-infrared galaxy luminosity function and colour bimodality up to z≃ 2 from the UKIDSS Ultra Deep Survey Early Data Release     

M. Cirasuolo  R. J. McLure  J. S. Dunlop  O. Almaini  S. Foucaud  Ian Smail  K. Sekiguchi  C. Simpson  S. Eales  S. Dye  M. G. Watson  M. J. Page  P. Hirst 《Monthly notices of the Royal Astronomical Society》2007,380(2):585-595

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Serpentinization and alteration in an olivine cumulate from the Stillwater Complex,Southwestern Montana     

Norman J. Page 《Contributions to Mineralogy and Petrology》1976,54(2):127-137

Some of the olivine cumulates of the Ultramafic zone of the Stillwater Complex, Montana, are progressively altered to serpentine minerals and thompsonite. Lizardite and chrysotile developed in the cumulus olivine and postcumulus pyroxenes; thompsonite developed in postcumulus plagioclase. The detailed mineralogy, petrology, and chemistry indicate that olivine and plagioclase react to form the alteration products, except for H₂O, without changes in the bulk composition of the rocks.  相似文献