4,973 research outputs found
Analysis of partially emerged corals and reef terraces in the central Vanuatu arc : comparison of contemporary coseismic and nonseismic with quaternary vertical movements
Bubbles and Filaments: Stirring a Cahn-Hilliard Fluid
The advective Cahn-Hilliard equation describes the competing processes of
stirring and separation in a two-phase fluid. Intuition suggests that bubbles
will form on a certain scale, and previous studies of Cahn-Hilliard dynamics
seem to suggest the presence of one dominant length scale. However, the
Cahn-Hilliard phase-separation mechanism contains a hyperdiffusion term and we
show that, by stirring the mixture at a sufficiently large amplitude, we excite
the diffusion and overwhelm the segregation to create a homogeneous liquid. At
intermediate amplitudes we see regions of bubbles coexisting with regions of
hyperdiffusive filaments. Thus, the problem possesses two dominant length
scales, associated with the bubbles and filaments. For simplicity, we use use a
chaotic flow that mimics turbulent stirring at large Prandtl number. We compare
our results with the case of variable mobility, in which growth of bubble size
is dominated by interfacial rather than bulk effects, and find qualitatively
similar results.Comment: 20 pages, 27 figures. RevTeX
Multichannel coupling with supersymmetric quantum mechanics and exactly-solvable model for Feshbach resonance
A new type of supersymmetric transformations of the coupled-channel radial
Schroedinger equation is introduced, which do not conserve the vanishing
behavior of solutions at the origin. Contrary to usual transformations, these
``non-conservative'' transformations allow, in the presence of thresholds, the
construction of potentials with coupled scattering matrices from uncoupled
potentials. As an example, an exactly-solvable potential matrix is obtained
which provides a very simple model of Feshbach-resonance phenomenon.Comment: 10 pages, 2 figure
The role of oxygen in the uptake of deuterium in lithiated graphite
We investigate the mechanism of deuterium retention by lithiated graphite and its relationship to the oxygen concentration through surface sensitive experiments and atomistic simulations. Deposition of lithium on graphite yielded 5%-8% oxygen surface concentration and when subsequently irradiated with D ions at energies between 500 and 1000 eV/amu and fluences over 10(16) cm(-2) the oxygen concentration rose to between 25% and 40%. These enhanced oxygen levels were reached in a few seconds compared to about 300 h when the lithiated graphite was allowed to adsorb oxygen from the ambient environment under equilibrium conditions. Irradiating graphite without lithium deposition, however, resulted in complete removal of oxygen to levels below the detection limit of XPS (e. g.
Non-perturbative Power Corrections to Ghost and Gluon Propagators
We study the dominant non-perturbative power corrections to the ghost and
gluon propagators in Landau gauge pure Yang-Mills theory using OPE and lattice
simulations. The leading order Wilson coefficients are proven to be the same
for both propagators. The ratio of the ghost and gluon propagators is thus free
from this dominant power correction. Indeed, a purely perturbative fit of this
ratio gives smaller value (MeV) of \Lambda_{\ms} than the one
obtained from the propagators separately(MeV). This argues in
favour of significant non-perturbative power corrections in the
ghost and gluon propagators. We check the self-consistency of the method.Comment: 14 pages, 4 figures; replaced with revised version, to appear in JHE
Supersymmetric transformations for coupled channels with threshold differences
The asymptotic behaviour of the superpotential of general SUSY
transformations for a coupled-channel Hamiltonian with different thresholds is
analyzed. It is shown that asymptotically the superpotential can tend to a
diagonal matrix with an arbitrary number of positive and negative entries
depending on the choice of the factorization solution. The transformation of
the Jost matrix is generalized to "non-conservative" SUSY transformations
introduced in Sparenberg et al (2006 J. Phys. A: Math. Gen. 39 L639). Applied
to the zero initial potential the method permits to construct superpartners
with a nontrivially coupled Jost-matrix. Illustrations are given for two- and
three-channel cases.Comment: 17 pages, 3 explicit examples and figures adde
Sequence verification of synthetic DNA by assembly of sequencing reads
Gene synthesis attempts to assemble user-defined DNA sequences with base-level precision. Verifying the sequences of construction intermediates and the final product of a gene synthesis project is a critical part of the workflow, yet one that has received the least attention. Sequence validation is equally important for other kinds of curated clone collections. Ensuring that the physical sequence of a clone matches its published sequence is a common quality control step performed at least once over the course of a research project. GenoREAD is a web-based application that breaks the sequence verification process into two steps: the assembly of sequencing reads and the alignment of the resulting contig with a reference sequence. GenoREAD can determine if a clone matches its reference sequence. Its sophisticated reporting features help identify and troubleshoot problems that arise during the sequence verification process. GenoREAD has been experimentally validated on thousands of gene-sized constructs from an ORFeome project, and on longer sequences including whole plasmids and synthetic chromosomes. Comparing GenoREAD results with those from manual analysis of the sequencing data demonstrates that GenoREAD tends to be conservative in its diagnostic. GenoREAD is available at www.genoread.or
Adherence to
(MWM) for palliative care has prioritized data collection efforts for evaluating quality in clinical practice. How these measures can be implemented across diverse clinical settings using point-of-care data collection on quality is unknown.To evaluate the implementation of MWM measures by exploring documentation of quality measure adherence across six diverse clinical settings inherent to palliative care practice.We deployed a point-of-care quality data collection system, the Quality Data Collection Tool, across five organizations within the Palliative Care Research Cooperative Group. Quality measures were recorded by clinicians or assistants near care delivery.During the study period, 1989 first visits were included for analysis. Our population was mostly white, female, and with moderate performance status. About half of consultations were seen on hospital general floors. We observed a wide range of adherence. The lowest adherence involved comprehensive assessments during the first visit in hospitalized patients in the intensive care unit (2.71%); the highest adherence across all settings, with an implementation of >95%, involved documentation of management of moderate/severe pain. We observed differences in adherence across clinical settings especially with MWM Measure #2 (Screening for Physical Symptoms, range 45.7%–81.8%); MWM Measure #5 (Discussion of Emotional Needs, range 46.1%–96.1%); and MWM Measure #6 (Documentation of Spiritual/Religious Concerns, range 0–69.6%).Variations in clinician documentation of adherence to MWM quality measures are seen across clinical settings. Additional studies are needed to better understand benchmarks and acceptable ranges for adherence tailored to various clinical settings
Examining possible foraging differences in urban and rural cave cricket populations: Carbon and nitrogen isotope ratios (δ13C, δ15N) as indicators of trophic level
unpublishednot peer reviewedOpe
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