the Quaternary vegetation history of the southeastern united states has not been well studied, particularly in comparison to more northerly regions of north america, and this is even more apparent on the coastal plain of georgia (e.g., Watts, 1971; rich and spackman, 1979; rich 1984a, 1984b, 1996; rich and pirkle, 1998). the coastal region of georgia is characterized by a string of barrier isla...

We present a comprehensive study of the nucleation kinetic of Cu on Ni~100! using variable-temperature scanning tunneling microscopy. The analysis of the saturation island density as a function of substrate temperature and deposition rate reveals that the smallest stable island abruptly changes from a dimer to a tetramer. From the Arrhenius plot, the migration barrier Em5~0.3560.02! eV, as well...

We present a model which describes diffusion and island growth on FCC(001) metal substrates during molecular beam epitaxy. This model incorporates the essential characteristics of adatom hopping. To test it we performed Monte Carlo simulations for the growth of Cu on Cu(001) using semi-empirical potentials. We find that due to high edge mobility, islands are compact in the entire temperature ra...

To date the global initiative to barcode all fishes, FISH-BOL, has delivered barcodes for approximately 14,400 of the 30,000 fish species; there is still much to do to attain its ultimate goal of barcoding all the world’s fishes. One strategy to overcome local gaps is to initiate short but intensive efforts to collect and barcode as many species as possible from a small region – a barcode ‘blit...

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Ornithodoros (Alectorobius) capensis Neumann, an ectoparasite of seabirds found circumglobally in the tropics and subtropics, has become established along the southeastern seacoast of the United States. The tick has been found feeding primarily on brown pelicans, Pelecanus occidentalis, but also has been found on the laughing gull, Larus atricilla, and the American oystercatcher, Haematopus pal...

Realization of a robust nanotube-heterostructure tunneling transistors [Solid State Comm. 116, 569 (2000)] requires the difficult formation [Science 293, 76 (2001)] of a central nanoscale barrier separating a pair of outside metallic leads. Here I suggest an alternative surface-based assembly based on self-organization of one-dimensional metallic states on oxides and trapping well-resolved reso...

Atomic force microscopy studies have been performed on GaAs (001) homoepitaxy Rlrns grown by molecular beam epitaxy. Multilayered features are seen to evolve when the growth conditions favor island nucleation. As the epilayer thickness is increased these features grow in all dimensions but the angle of inclination remains approximately constant at 1”. The mounding does not occur on surfaces gro...