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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.12.010 Byline: T.C. Siewicki, T. Pullaro, W. Pan, S. McDaniel, R. Glenn, J. Stewart Keywords: Coliform bacteria; Wildlife; Ecological modeling; Statistical modeling Abstract: Models that accurately predict fecal coliform bacteria (FCB) concentrations, one of the most widely used measures of estuarine water quality, are needed to improve land use decision-making. Rapidly occurring changes in coastal land uses and the influence on water quality increases the urgency of having improved decision tools. For this study, samples were collected monthly from six coastal ponds, two tidal creeks and four shallow water wells for up to 21/2 years. These data were used along with other measures of environmental conditions and land classes within each watershed to construct quantitative relationships between combinations of variables and both total and presumed wildlife sources of FCB. Linear regression, bootstrapping and generalized additive modeling that incorporates both linear and nonlinear terms were used. Results of repeated simultaneous sampling on the same tide stage of ponds and downstream estuarine creeks suggest that most FCB come from wildlife and that the ponds effectively remove these bacteria except immediately following heavy rainfall. Predictive models for concentrations of total and presumed wildlife bacteria are provided along with simple measures to estimate watershed boundaries. It is proposed that these tools can be used to minimize impacts on receiving water body quality. The models can be used to test alternative development approaches within coastal watersheds similar to that found in the southeastern USA coastal zone as well as to evaluate specific proposed landscape alterations. Author Affiliation: Center for Coastal Environmental Health and Biomolecular Research, National Ocean Service, NOAA, 219 Fort Johnson Road, Charleston, SC 29412-9110, USA Article History: Received 21 May 2005; Revised 15 October 2005; Accepted 13 December 2005

Abstract: We report on the first γ spectroscopy of 66Se and 65As from two-neutron removal at intermediate beam energies. The deduced excitation energies for the first-excited states in 66Se and 65As are compared to mean-field-based predictions within a collective Hamiltonian formalism using the Gogny D1S effective interaction and to state-of-the-art shell-model calculations restricted to the valence space. The obtained Coulomb-energy differences for the first excited states in 66Se and 65As are discussed within the shell-model formalism to assess the shape-coexistence picture for both nuclei. Our results support a favored oblate ground-state deformation in 66Se and 65As. A shape transition for the ground state of even–odd As isotopes from oblate in 65As to prolate in 67,69,71As is suggested. [Copyright &y& Elsevier]

Abstract: We report on the first in-beam γ-ray spectroscopy of 23Al using two different reactions at intermediate beam energies: inelastic scattering off 9Be and heavy-ion induced one-proton pickup, 9Be(22Mg,23Al+γ)X, at 75.1 MeV/nucleon. A γ-ray transition at 1616(8) keV—exceeding the proton separation energy by 1494 keV—was observed in both reactions. From shell model and proton decay calculations we argue that this γ-ray decay proceeds from the core-excited state to the ground state of 23Al. The proposed nature of this state, [22Mg, is consistent with the presence of a γ-branch and with the population of this state in the two reactions. [Copyright &y& Elsevier]

Abstract: The scintillator material LaBr3:Ce, which was discovered in 2001, has grown in popularity for a variety of applications in homeland security and nuclear medicine. In this paper we investigate its use for nuclear science spectroscopy applications in the context of in-beam gamma-ray spectroscopy with fast ion beams. In such experiments, the Doppler broadening of the gamma-ray line measured with a finite-size detector in the laboratory fundamentally limits the achievable energy resolution. For a typical experiment this effect is of the order of 3%. With the intrinsic energy resolution of LaBr3:Ce better than 3% FWHM at 662keV, and its favorable stopping power, it could be a nearly ideal scintillator for gamma-ray spectroscopy applications with fast beams. Results from in-beam gamma-ray spectroscopy measurements using two LaBr3:Ce scintillators are presented and compared to results from segmented germanium detectors. Results from these measurements suggest that LaBr3:Ce based scintillation arrays can provide a viable tool for many experiments. Additionally, we show that the excellent timing properties of LaBr3:Ce can significantly reduce background events in the gamma-ray spectra. [Copyright &y& Elsevier]