New H-band galaxy number counts: a large local hole in the galaxy distribution     

W. J. Frith  N. Metcalfe  T. Shanks 《Monthly notices of the Royal Astronomical Society》2006,371(4):1601-1609

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Galaxy number counts – VI. An H-band survey of the Herschel Deep Field     

N. Metcalfe  T. Shanks  P. M. Weilbacher †  H. J. McCracken ‡  R. Fong  D. Thompson 《Monthly notices of the Royal Astronomical Society》2006,370(3):1257-1273

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The core/envelope symmetry in pulsating stars     

M. H. Montgomery  T. S. Metcalfe  D. E. Winget 《Monthly notices of the Royal Astronomical Society》2003,344(2):657-664

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Identification of rainfall–runoff model for improved baseflow estimation in ungauged basins     

Jos Samuel  Paulin Coulibaly  Robert A. Metcalfe 《水文研究》2012,26(3):356-366

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Intra- and inter-species differences in persistent organic contaminants in the blubber of blue whales and humpback whales from the Gulf of St. Lawrence, Canada     

Metcalfe C  Koenig B  Metcalfe T  Paterson G  Sears R 《Marine environmental research》2004,57(4):245-260

Biopsy samples of blubber from adult male and female blue whales, and from female and young-of-the-year humpback whales were collected during the summers of 1992-1999 in the Gulf of St. Lawrence, Canada. In blue whales, concentrations of 25 PCB congeners, DDT and metabolites and several other organochlorine compounds were present at higher concentrations in the blubber of males relative to females; reflecting maternal transfer of these persistent contaminants from females into young. Sex-related differences in concentrations were not observed with less persistent contaminants, such as HCHs. In humpback whale samples, there were no significant differences in the concentrations of PCBs and organochlorine compounds in the blubber of females and calves. These data indicate that calves quickly bioaccumulate contaminants by transplacental and lactational routes to concentrations that are in equilibrium with females. In comparisons between contaminant concentrations and patterns in the blubber of female blue and humpback whales, there were no significant differences in concentrations, but the proportions of some PCB congeners, HCH isomers, and DDT and its metabolites were different in the two baleen whale species. These may reflect differences in the diet of the two species, since fish comprise a large part of the diet of humpback whales and blue whales feed exclusively on euphausiid crustaceans (i.e. krill).  相似文献   

Digital Terrane Map of East and Southeast Asia     

Koji Wakita  Ian Metcalfe  Shigeki Hada 《Gondwana Research》1999,2(4):613-614

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Whole Earth Telescope observations of the hot helium atmosphere pulsating white dwarf EC 20058−5234     

D. J. Sullivan †  T. S. Metcalfe  D. O'Donoghue  D. E. Winget  D. Kilkenny  F. van Wyk  A. Kanaan  S. O. Kepler  A. Nitta  S. D. Kawaler  M. H. Montgomery  R. E. Nather  M. S. O'Brien  A. Bischoff-Kim  M. Wood  X. J. Jiang  E. M. Leibowitz  P. Ibbetson  S. Zola  J. Krzesinski  G. Pajdosz  G. Vauclair  N. Dolez  M. Chevreton 《Monthly notices of the Royal Astronomical Society》2008,387(1):137-152

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Investigating Late Holocene Climate Variability in Central Mexico using Carbon Isotope Ratios in Organic Materials and Oxygen Isotope Ratios from Diatom Silica within Lacustrine Sediments     

Melanie J.?LengEmail author  Sarah?E.?Metcalfe  Sarah?J.?Davies 《Journal of Paleolimnology》2005,34(4):413-431

Previous studies have shown that moisture availability in the central highlands of Mexico during the last 3000 years has been highly variable, but evidence remains ambiguous since the climatic signal is partially masked by that of human activity. Here we use two isotope systems to provide evidence for environmental change in Laguna Zacapu, Michoacán covering this time period. Carbon isotope ratios of organic material suggest that there have been fluctuations in the carbon pool related to plant productivity, possibly as a result of changes in the abundance of aquatic plants around the lake margins. The drainage basin and lake have been managed intensively during the 20th century. Lake level apparently fell during the early part of the century, but has been artificially controlled since the 1950s. The oxygen isotope ratios from diatom silica should provide the more unambiguous climate signal, although we show that the interpretation of the diatom oxygen isotope record is far from straight forward. Zacapu is a spring-fed, non-evaporating system and changes in δ¹⁸O_diatom are likely to be a function of changes in δ¹⁸O of precipitation, due to either temperature and salinity variation in the Gulf of Mexico (associated with changes in the Bond cycles from the North Atlantic or the Loop current from the Carribean) and/or changing moisture contributions from different air masses (Gulf of Mexico vs. Pacific). Changes in the Gulf of Mexico are possibly at a resolution comparable to the periodicity we see in the δ¹⁸O_diatom record, although without better dating the comparison is speculative.  相似文献   

Late holocene human impact on lake basins in central mexico     

S. E. Metcalfe  F. A. Street-Perrott  R. B. Brown  P. E. Hales  R. A. Perrott  F. M. Steininger 《Geoarchaeology》1989,4(2):119-141

Palaeolimnological investigations in the volcanic highlands of Central Mexico (19°N) have yielded clear evidence of environmental degradation associated with episodes of forest clearance and agricultural expansion during the last 3500 years. Preliminary results are presented from five lake basins situated at altitudes of 1700 to 2575 m a.s.l., along a gradient of decreasing aridity and temperature from north to south: Hoya San Nicolás de Parangueo (Guanajuato); La Piscina de Yuriria (Guanajuato); Pátzcuaro (Michoacán); Zacapu (Michoacán) and Upper Lerma (Estado de México). Samples from sediment cores and pits are being analyzed for loss-on-ignition, magnetic susceptibility (X and X_fd), major cations, total P, C/N, carbonate content, δ¹³C, δ¹⁸O, diatoms, pollen, and charcoal content. Evidence for disturbance is provided by increases in non-arboreal pollen types, especially maize (Zea mays), peaks of X, X_fd and charcoal; increased concentrations of elements associated with soil material such as Al, Fe, Ti, and P, and diatoms indicative of cultural eutrophication. Pátzcuaro, Hoya San Nicolás, Zacapu, and Upper Lerma show an initial phase of disturbance dating from ca. 3500 to 1400 yr B.P., reflecting the widespread adoption of maize cultivation during the Preclassic. A later, more intense phase is recorded in all the basins. In Hoya San Nicolás, La Piscina de Yuriria, Zacapu, and Pátzcuaro, which lay within, or on the margins of the Tarascan state, this episode dates from Postclassic to Hispanic times (<1100 yr B.P.). In contrast, disturbance in the Matlatzincan area (the Upper Lerma Basin) was apparently more continuous, culminating during the late Classic to early Postclassic (ca. 1400-700 yr B.P.).  相似文献