Andrew R. Lewis

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A thin glacial diamicton, informally termed Granite drift, occupies the floor of central Beacon Valley in southern Victoria Land, Antarctica. This drift is ,1.0 m thick and rests with sharp planar contacts on stagnant glacier ice reportedly of Miocene age, older than 8.1 Ma. The age of the ice is based on 40Ar/39Ar analyses of presumed in situ ash-fall(More)
 This study quantifies the contributions of larval recruitment and post-recruit (juvenile and adult) immigration to net increases in population size for 150 species of fishes found on ten isolated coral patches or ‘bommies’ (108–267 m2) within a typical reef of the Great Barrier Reef system. At least one third of the total number of recruits and immigrants(More)
We present a glacial record from the western Olympus Range, East Antarctica, that documents a permanent shift in the thermal regime of local glaciers, from wet to cold based, between 14.11 and 13.94 million years ago (Ma). The record includes classic wet-based tills interbedded with fossil-rich glaciolacustrine deposits overlain by a series of cold-based(More)
Optimal foraging models predict that large predators should concentrate on large prey in order to maximize their net gain of energy intake. Here, we show that the largest species of sea turtle, Dermochelys coriacea, does not strictly adhere to this general pattern. Field observations combined with a theoretical model suggest that a 300 kg leatherback turtle(More)
We present a technique that uses (13)C NMR spectroscopy to measure kinetic isotope effects on the second-order rate constant (k(cat)/K(m)) for enzyme-catalyzed reactions. Using only milligram quantities of isotopically labeled substrates, precise competitive KIEs can be determined while following the ongoing reaction directly in a NMR spectrometer. Our(More)
X-ray crystallographic data of the carbohydrate mimic MDWNMHAA when bound to an anti-Shigella flexneri Y mAb SYA/J6 indicate the immobilization of water molecules, that is, the presence of "bound" waters, in the active site. Water Ligand Observed via Gradient Spectroscopy (WaterLOGSY) was used in conjunction with saturation transfer difference (STD)-NMR(More)
Department of Geosciences, North Dakota State University, Fargo, ND 58105, U.S.A. (allan.ashworth@ndsu.edu; adam.r.lewis.1@ndsu.edu) Department of Earth Sciences, Boston University, Boston, MA 02215, U.S.A. (marchant@bu.edu) 1930 Bunkhouse Drive, Jackson, WY 83001, U.S.A. (askin@bresnan.net) Plant Sciences and Biodiversity, Royal Botanic Gardens Melbourne,(More)
The local structure of the [SiO(4/2)F]- unit in fluoride-containing as-synthesized STF zeolite has been experimentally determined by a combination of solid-state NMR and microcrystal X-ray diffraction to be very close to trigonal bipyramidal. Because the fluoride ions are disordered over two sites, the resulting local structure of the [SiO(4/2)F]- unit from(More)
A general protocol is described for structure determinations of organic sorbate-zeolite complexes based on the selective, through-space, distance-dependent transfer of magnetization from protons in selectively deuterated organics to framework silicon nuclei. The method was developed using the known structure of the high-loaded ZSM-5/p-xylene complex(More)
P450(cam) (CYP101A1) is a bacterial monooxygenase that is known to catalyze the oxidation of camphor, the first committed step in camphor degradation, with simultaneous reduction of oxygen (O2). We report that P450(cam) catalysis is controlled by oxygen levels: at high O2 concentration, P450(cam) catalyzes the known oxidation reaction, whereas at low O2(More)