Small pelagics in upwelling systems: patterns of interaction and structural changes in "wasp-waist" ecosystems     

Cury  Philippe; Bakun  Andrew; Crawford  Robert J. M.; Jarre  Astrid; Quinones  Renato A.; Shannon  Lynne J.; Verheye  Hans M. 《ICES Journal of Marine Science》2000,57(3):603-618

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WRF model sensitivity to choice of parameterization: a study of the ‘York Flood 1999’   总被引：1，自引：0，他引：1  

Renji Remesan  Tim Bellerby  Ian Holman  Lynne Frostick 《Theoretical and Applied Climatology》2015,122(1-2):229-247

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Biodegradation of toxic chemicals in Guayanilla Bay,Puerto Rico   总被引：1，自引：0，他引：1  

Zaidi BR  Hinkey LM  Rodríguez NR  Govind NS  Imam SH 《Marine pollution bulletin》2003,46(4):418-423

Studies were conducted to assess the factors that may influence the rate and extent of biodegradation of biphenyl, naphthalene, phenanthrene, pentachlorophenol (PCP) and p-nitrophenol in water samples collected from the Guayanilla Bay (18 degrees N; 67.45 degrees W), southwest of Puerto Rico. In vitro studies mediated slow degradation of biphenyl, naphthalene and phenanthrene substrates by natural microbial flora present in the Bay. Addition of KNO(3) as a source of inorganic N greatly enhanced the degradation of phenanthrene but not of naphthalene, suggesting that effects on degradation due to nutrient limitation were compound specific. The rate and extent of degradation of naphthalene and PCP were higher in water samples collected closer to the source of contamination, i.e. the petrochemical complex. The identity of a phenanthrene degrading bacterium, previously identified by conventional phenotypic method (Zaidi et al., Utilizing Nature's Advanced Materials, Oxford Unviersity Press, 1999) as Alteromonas sp., was confirmed by partial DNA sequencing of the small subunit rRNA gene.  相似文献   

Ensemble properties of comets in the Sloan Digital Sky Survey     

Michael Solontoi  Željko Ivezić  Mario Jurić  Andrew C. Becker  Lynne Jones  Andrew A. West  Steve Kent  Robert H. Lupton  Mark Claire  Gillian R. Knapp  Tom Quinn  James E. Gunn  Donald P. Schneider 《Icarus》2012,218(1):571-584

We present the ensemble properties of 31 comets (27 resolved and 4 unresolved) observed by the Sloan Digital Sky Survey (SDSS). This sample of comets represents about 1 comet per 10 million SDSS photometric objects. Five-band (u, g, r, i, z) photometry is used to determine the comets’ colors, sizes, surface brightness profiles, and rates of dust production in terms of the Afρ formalism. We find that the cumulative luminosity function for the Jupiter Family Comets in our sample is well fit by a power law of the form N(<H) ∝ 10^{(0.49±0.05)H} for H < 18, with evidence of a much shallower fit N(<H) ∝ 10^{(0.19±0.03)H} for the faint (14.5 < H < 18) comets. The resolved comets show an extremely narrow distribution of colors (0.57 ± 0.05 in g ? r for example), which are statistically indistinguishable from that of the Jupiter Trojans. Further, there is no evidence of correlation between color and physical, dynamical, or observational parameters for the observed comets.  相似文献   

The nature of publishing and assessment in Geography and Environmental Studies: evidence from the Research Assessment Exercise 2008     

Keith Richards  Mike Batty  Kevin Edwards  Allan Findlay  Giles Foody  Lynne Frostick  Kelvyn Jones  Roger Lee  David Livingstone  Terry Marsden  Judith Petts  Chris Philo  David Simon  Susan Smith  David Thomas 《Area》2009,41(3):231-243

We present a summary of the kinds of outputs submitted to the Geography and Environmental Studies sub-panel (H-32) for the 2008 Research Assessment Exercise (RAE), and examine the relationships between the peer assessment of research quality that the RAE process has typified, and alternative modes of assessment based on bibliometrics. This comparison is effected using (in aggregate form) some of the results from the RAE, together with citation data gathered after completion of the RAE assessment, specifically for the purpose of this paper. We conclude that, if it continues to be necessary and desirable to assess, in some measure and however imprecisely, research quality, then peer assessment cannot be replaced by bibliometrics. Bibliometrics permit measurement of something that may be linked to quality but is essentially a different phenomenon – a measure of 'impact', for example.  相似文献   

Regime shifts in upwelling ecosystems: observed changes and possible mechanisms in the northern and southern Benguela     

Philippe Cury  Lynne Shannon   《Progress in Oceanography》2004,60(2-4):223

A regime shift is considered to be a sudden shift in structure and functioning of a marine ecosystem, affecting several living components and resulting in an alternate state. According to this definition, regime shifts differ from species replacement or alternation of species at similar trophic levels, whereby the ecosystem is not necessarily significantly altered in terms of its structure and function; only its species composition changes. This paper provides an overview of regime shifts, species replacements and alternations that have been observed in the northern and southern Benguela ecosystems over the past few decades. Bottom-up control, initiating and sustaining regime shifts or species replacements via environmental forcing, is documented for both the southern and the northern Benguela ecosystems. Fishing (a case of top-down control) appears to have played an important role in regime shift processes in the Namibian ecosystem. Very low biomass levels of exploited fish stocks associated with less efficient energy transfer in the northern Benguela are indicative of a regime shift. Very high biomass levels have been reached in the southern Benguela in the 2000s. However the alternation between sardine and anchovy that has been observed in the southern Benguela over the last two decades appears not to have had major effects on the overall functioning of the ecosystem. The consequences of regime shifts for exploitation are highlighted, suggesting that fisheries managers should move towards a more effective ecosystem approach to fisheries.  相似文献   

Extended structures around yso in Mid-IR broad emission features     

Lynne K. Deutsch  Joseph L. Hora  Harold M. Butner  William F. Hoffmann  Giovanni G. Fazio 《Astrophysics and Space Science》1995,231(1-2):89-92

We present CO(1-0) observations toward the soft gamma-ray repeater SGR 1806-20. We discuss the implications on the distance to the X-ray counterpart: AX 1805.7-2025. We also present an upper limit at = 1.3 mm for the thermal emission from dust and high resolution IRAS maps of the region. SGR 1806-20 is very likely associated with the H II complex W31. The G10.0-0.3 supernova remnant (SNR) could be expanding in the very low density region produced by the wind of the bright O9-B2 star recently detected.National Academy of Sciences / National Research Council Resident Research Associate  相似文献   

Holocene variability in climate and oceanic conditions in the winter rainfall zone of South Africa—inferred from a high resolution diatom record from Verlorenvlei     

Kelly L. Kirsten  Thomas Kasper  Hayley C. Cawthra  Paul Strobel  Lynne J. Quick  Michael E. Meadows  Torsten Haberzettl 《第四纪科学杂志》2020,35(4):572-581

We present a diatom record from a well-dated 15.25 m composite sedimentary core from Verlorenvlei, a shallow coastal lake on the west coast of South Africa. We show that fluctuations in the diatom record occur in response to changes in sea level, ocean–atmosphere interactions and latitudinal shifts in the wind belts. During the early to mid-Holocene, the system primarily responds to sea level changes. A marine community that favours high nutrients is evident, particularly during 9200–8000, 7420–7000 and 6200–5600 cal a bp , corroborating periods of Benguela upwelling linked to fluctuations in the southeast trade winds. Increases in bioproductivity (%TOC, C/N) and fresher-water diatoms are associated with wetter conditions over the region and the northward migration of the southern westerly wind belt, most notably between 8000 and 7500 cal a bp and over the last 700 years. The latter trends are concomitant with changes in the extent of Antarctic sea ice and availability of moisture in southern South America. During the late Holocene, as sea levels stabilised to modern levels, climate variability is more strongly evident. The body of evidence further reveals the sensitivity of the region to high-latitude atmospheric mechanisms, but also showcases the significance of the southeast trade winds.  相似文献   

A high‐resolution record of Holocene climate and vegetation dynamics from the southern Cape coast of South Africa: pollen and microcharcoal evidence from Eilandvlei          下载免费PDF全文

Lynne J. Quick  Brian M. Chase  Michael Wündsch  Kelly L. Kirsten  Manuel Chevalier  Roland Mäusbacher  Michael E. Meadows  Torsten Haberzettl 《第四纪科学杂志》2018,33(5):487-500

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Exposing local adaptation: synergistic stressors elicit population-specific lactate dehydrogenase-B (<Emphasis Type="Italic">ldh</Emphasis>-<Emphasis Type="Italic">b</Emphasis>) expression profiles in Australian barramundi, <Emphasis Type="Italic">Lates calcarifer</Emphasis>     

Richard?C.?EdmundsEmail author  Carolyn?Smith-Keune  Lynne?van Herwerden  Christopher?J.?Fulton  Dean?R.?Jerry 《Aquatic Sciences - Research Across Boundaries》2012,74(1):171-178

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