A Method To Detect Viable Helicobacter pylori Bacteria in Groundwater     

Debbie Flanigan  Mark Rodgers 《洁净——土壤、空气、水》2003,31(1):45-48

The inability to detect the presence of viable Helicobacter pylori bacteria in environmental waters has hindered the public health community in assessing the role water may play in the transmission of this pathogen. This work describes a cultural enrichment method coupled with an H. pylori‐specific PCR to identify these bacteria in water. While far from perfected at the present time, this represents an exciting new approach to studying the significance of water as a transmission mechanism for H. pylori. Evidence is presented that indicates culturable H. pylori bacteria were found using this enrichment/PCR method in a local groundwater source.  相似文献   

Gravitational and buckling instabilities of a rheologically layered structure: implications for salt diapirism   总被引：2，自引：0，他引：2  

Alik T. Ismail-Zadeh  Herbert E. Huppert  John R. Lister 《Geophysical Journal International》2002,148(2):288-302

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Results from the Wide Angle Search for Planets Prototype (WASP0) – III. Planet hunting in the Draco field     

Stephen R. Kane †  rew Collier Cameron  Keith Horne  David James  T. A. Lister  Don L. Pollacco  Rachel A. Street  Yiannis Tsapras 《Monthly notices of the Royal Astronomical Society》2005,364(3):1091-1103

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Vegetation controls on small‐scale runoff and erosion dynamics in a degrading dryland environment     

Katerina Michaelides  Debbie Lister  John Wainwright  Anthony J. Parsons 《水文研究》2009,23(11):1617-1630

This paper investigates the controls of vegetation on runoff and erosion dynamics in the dryland environment of Jornada, New Mexico, USA. As the American southwest has seen significant shifts in the dominant vegetation species in the past 150 years, an understanding of the vegetation effects on hydrological and erosional processes is vital for understanding and managing environmental change. Small‐scale rainfall simulations were carried out to identify the hydrological and erosional processes resulting from the grassland and shrubland vegetation species. Results obtained using tree‐regression analysis suggested that the primary vegetation control on runoff and erosion is the shrub type and canopy density, which directly affects the local microtopographic gradient of mounds beneath the shrubs. Significant interactions and feedbacks were found to occur among the local mound gradient, crust cover, soil aggregate stability and antecedent soil moisture between the different vegetation species for both the runoff and erosion responses. Although some of the shrub species were found to produce higher sediment yields than the grass species, the distinguishing feature of the grassland was the significantly higher enrichment in the fine sediment fraction compared to all other surface cover types. This enrichment in fines has important implications for nutrient movement in such environments. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

Starspot distributions on XY UMa during 1997–2000 from eclipse mapping     

T.A. Lister  A. Collier Cameron  R.W. Hilditch 《Monthly notices of the Royal Astronomical Society》2001,326(4):1489-1498

We present narrow-band red light curves and surface maps of the short-period RS CVn binary system XY UMa, obtained between 1997 January and 2000 March. The light-curve morphology of this system is known to vary on time-scales of a few days. We have used eclipse-mapping techniques to map the distribution of cool starspots on the surface of the primary star. The resulting maps show the continued evolution of spot features on time-scales of a few days to a week. By comparison with the images of Collier Cameron & Hilditch, we also find evidence for longer term trends, including a decline to an activity minimum during 1997 and a rise in activity during 1998–2000. We also find marginal evidence from the O–C ephemeris curves for a periodicity and a peak corresponding to the time of activity minimum.  相似文献   

White mica 40Ar/39Ar age spectra and the timing of multiple episodes of high‐P metamorphic mineral growth in the Cycladic eclogite–blueschist belt,Syros, Aegean Sea,Greece          下载免费PDF全文

G. S. Lister  M. A. Forster 《Journal of Metamorphic Geology》2016,34(5):401-421

New geochronology from Syros in the Cycladic eclogite–blueschist belt, Aegean Sea, Greece, shows that ⁴⁰Ar/³⁹Ar geochronology consistently dates microstructural events in metamorphic rocks. We demonstrate that the age spectra depend on microstructure in a predictable and systematic way. Ages can be inferred by applying the method of asymptotes and limits to data from the step ‐ heating experiments. The results are consistent with previously published estimates for the timing of a sequence of distinct and discrete episodes of high ‐ P metamorphic mineral growth observed regionally across this belt. Arrhenius plots from these experiments imply that phengitic white mica is highly retentive of argon, and therefore (if these data can be extrapolated to the natural environment) the ages can be interpreted as recording the timing of episodic deformation and metamorphism. Porphyroblastic growth begins: (i) for omphacite – jadeite–eclogite facies parageneses at c. 53 Ma; and (ii) for garnet – glaucophane facies parageneses at c. 47 Ma. The Kini Shear Zone started as an extensional post ‐ epidote–albite‐transitional–blueschist facies shear zone that had completed operation by c. 31 Ma. The scatter in ages is due to the effect of deformation, recrystallization and multiple growth events in shear zones that continued operating for 3 – 6 million years from the start of each episode.  相似文献   

Implications of sampling design and sample size for national carbon accounting systems     

Köhl M  Lister A  Scott CT  Baldauf T  Plugge D 《Carbon balance and management》2011,6(1):10

Background  

Countries willing to adopt a REDD regime need to establish a national Measurement, Reporting and Verification (MRV) system that provides information on forest carbon stocks and carbon stock changes. Due to the extensive areas covered by forests the information is generally obtained by sample based surveys. Most operational sampling approaches utilize a combination of earth-observation data and in-situ field assessments as data sources.  相似文献   

High-resolution Doppler images of the spotted contact binary AE Phe     

J. R. Barnes  T. A. Lister  R. W. Hilditch  A. Collier Cameron 《Monthly notices of the Royal Astronomical Society》2004,348(4):1321-1331

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The properties of extragalactic radio sources selected at 20 GHz     

Elaine M. Sadler  Roberto Ricci  Ronald D. Ekers  J. A. Ekers  Paul J. Hancock  Carole A. Jackson  Michael J. Kesteven  Tara Murphy  Chris Phillips  Robert F. Reinfrank  Lister Staveley-Smith  Ravi Subrahmanyan  Mark A. Walker  Warwick E. Wilson  Gianfranco De Zotti 《Monthly notices of the Royal Astronomical Society》2006,371(2):898-914

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Results from the Wide-Angle Search for Planets prototype (WASP0) – I. Analysis of the Pegasus field     

Stephen R. Kane  rew Collier Cameron  Keith Horne  David James  Tim A. Lister  Don L. Pollacco  Rachel A. Street  Yiannis Tsapras 《Monthly notices of the Royal Astronomical Society》2004,353(2):689-696

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