27 research outputs found
Axial morphology along the Southern Chile Rise
Author Posting. © The Author(s), 2012. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Marine Geology 315-318 (2012): 58-63, doi:10.1016/j.margeo.2012.06.001.Morphology of four spreading segments on the southern Chile Rise is described based on
multi-beam bathymetric data collected along the axial zones. The distribution of axial volcanoes,
the character of rift valley scarps, and the average depths vary between Segment 1 in the south,
terminating at the Chile Triple Junction, and Segment 4 in the north, which are separated by
three intervening transform faults. Despite this general variability, there is a consistent pattern of
clockwise rotation of the southern-most axial volcanic ridge within each of Segments 2, 3, and 4,
relative to the overall trend of the rift valley. A combination of local ridge-transform intersection
stresses and regional tectonics may influence spreading axis evolution in this sense.This work was
supported by NOAA/OE grant NA08OAR4600757 and University of California Ship Funds
Metastability in Two Dimensions and the Effective Potential
We study analytically and numerically the decay of a metastable phase in
(2+1)-dimensional classical scalar field theory coupled to a heat bath, which
is equivalent to two-dimensional Euclidean quantum field theory at zero
temperature. By a numerical simulation we obtain the nucleation barrier as a
function of the parameters of the potential, and compare it to the theoretical
prediction from the bounce (critical bubble) calculation. We find the
nucleation barrier to be accurately predicted by theory using the bounce
configuration obtained from the tree-level (``classical'') effective action.
Within the range of parameters probed, we found that using the bounce derived
from the one-loop effective action requires an unnaturally large prefactor to
match the lattice results. Deviations from the tree-level prediction are seen
in the regime where loop corrections would be expected to become important.Comment: 13pp, LaTex with Postscript figs, CLNS 93/1202, DART-HEP-93/0
Expanding Bubbles in a Thermal Background
Real scalar field models incorporating asymmetric double well potentials will
decay to the state of lowest energy. While the eventual nature of the system
can be discerned, the determination of the dynamics of the bubble wall provides
many difficulties. In the present study we investigate numerically the
evolution of spherically symmetric expanding bubbles coupled to a thermal bath
in 3+1 dimensions. A Markovian Langevin equation is employed to describe the
interaction between bubble and bath. We find the shape and velocity of the wall
to be independent of temperature, yet extremely sensitive to both asymmetry and
viscosity.Comment: RevTeX, 9 pages (multicols), 9 figures, submitted to Phys. Rev.
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Protecting drinking water: Rapid detection of human fecal contamination, injured and non-culturable pathogenic microbes in water systems
The rapid, potentially-automatable extraction of filter retentates has allowed quantitative detection of the unique biomarker for human fecal contamination, coprostanol, and the signature lipid biomarkers for total cellular biomass, viable cellular biomass, lipopolysaccharide (endotoxin). This method may be integrated with DNA based gene probe analysis for specific strains and enzyme activities. Not only does the analysis provide for detection of injured and non-culturable microbes but it also provides biomarkers characteristic of microbes exposed to biocides and disinfectants that can be utilized to monitor effectiveness of water mitigation/treatment. The analysis schemes involve filtration of the water or direct extraction of biofilms in sidestream chambers, supercritical fluid and/or liquid extraction, derivatization, and analysis of ``signature`` patterns by gas chromatography/mass spectrometry. Signature lipid biomarkers of interest are diglycerides, steroids including coprostanol and its isomers, poly-{beta}- hydroxyalcanoates (PHA), phospholipid ester-linked fatty acids (PLFA), and the lipopolysaccharide lipid A hydroxy fatty acids. PLFA found in polar lipid fractions estimate total viable cellular biomass, whereas the total cellular biomass can be calculated from diglyceride/phospholipid ester-linked fatty acids ratios. Furthermore, direct evidence of mitigation/treatment effectiveness can be ascertained by detection of diglycerides, respiratory quinones, PHA, and PLFA markers indicative of metabolic stress and toxicity such as trans monoenoic PLFA as well as oxirane and dicarboxylic fatty acids derived from the PLFA
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Wyoming Wild Horse and Cattle Grazing Research
This material was digitized as part of a cooperative project between the Society for Range Management, the National Agricultural Library, and the University of Arizona Libraries.The Rangelands archives are made available by the Society for Range Management and the University of Arizona Libraries. Contact [email protected] for further information.Migrated from OJS platform March 202
Strategies and Solutions in eHealth: a Literature Review
This study has three purposes: first, to provide a synthetic, up-to-date
overview of the main emerging strategies for the health care sector in the Western developed countries; second, to understand the possible role of eHealth solutions in each of these emerging strategies; third, to understand how these emerging health care strategies and emerging eHealth solutions may be usefully applied to address one of the most important challenges for health care systems, i.e. population ageing. The overview on emerging strategies and emerging eHealth solutions provided here is based on a literature review including a wide spectrum of recent documents published on the Web about health care and eHealth. The outcome of this document search is a concept matrix linking emerging health care strategies and emerging eHealth solutions. This concept matrix is used as a framework to synthetically describe how eHealth initiatives are perceived by different stakeholders, such as investors, policy makers, insurance companies, PA bodies, researchers and academics, health care professionals, patients