1,432 research outputs found
Loop-Erasure of Plane Brownian Motion
We use the coupling technique to prove that there exists a loop-erasure of a
plane Brownian motion stopped on exiting a simply connected domain, and the
loop-erased curve is the reversal of a radial SLE curve.Comment: 10 page
Multiconfiguration Time-Dependent Hartree-Fock Treatment of Electronic and Nuclear Dynamics in Diatomic Molecules
The multiconfiguration time-dependent Hartree-Fock (MCTDHF) method is
formulated for treating the coupled electronic and nuclear dynamics of diatomic
molecules without the Born- Oppenheimer approximation. The method treats the
full dimensionality of the electronic motion, uses no model interactions, and
is in principle capable of an exact nonrelativistic description of diatomics in
electromagnetic fields. An expansion of the wave function in terms of
configurations of orbitals whose dependence on internuclear distance is only
that provided by the underlying prolate spheroidal coordinate system is
demonstrated to provide the key simplifications of the working equations that
allow their practical solution. Photoionization cross sections are also
computed from the MCTDHF wave function in calculations using short pulses.Comment: Submitted to Phys Rev
The Hitting Times with Taboo for a Random Walk on an Integer Lattice
For a symmetric, homogeneous and irreducible random walk on d-dimensional
integer lattice Z^d, having zero mean and a finite variance of jumps, we study
the passage times (with possible infinite values) determined by the starting
point x, the hitting state y and the taboo state z. We find the probability
that these passages times are finite and analyze the tails of their cumulative
distribution functions. In particular, it turns out that for the random walk on
Z^d, except for a simple (nearest neighbor) random walk on Z, the order of the
tail decrease is specified by dimension d only. In contrast, for a simple
random walk on Z, the asymptotic properties of hitting times with taboo
essentially depend on the mutual location of the points x, y and z. These
problems originated in our recent study of branching random walk on Z^d with a
single source of branching
Traditional and Complementary Medicine Use Among Indigenous Cancer Patients in Australia, Canada, New Zealand, and the United States: A Systematic Review
© The Author(s) 2018. Background: Cancer ‘patients’ are increasingly using traditional indigenous and complementary medicines (T&CM) alongside conventional medical treatments to both cure and cope with their cancer diagnoses. To date T&CM use among Indigenous cancer patients from Australia, Canada, New Zealand, and the United States has not been systematically reviewed. Methods: We systematically searched bibliographic databases to identify original research published between January 2000 and October 2017 regarding T&CM use by Indigenous cancer patients in Australia, Canada, New Zealand, and the United States. Data from records meeting eligibility criteria were extracted and appraised for quality by 2 independent reviewers. Results: Twenty-one journal articles from 18 studies across all 4 countries met our inclusion criteria. T&CM use ranged from 19% to 57.7% (differing across countries). T&CM was mostly used concurrently with conventional cancer treatments to meet their spiritual, emotional, social, and cultural needs; however, bush, traditional, and herbal medicines were used in a minority of cases as an alternative. Conclusions: Our findings highlight the importance of T&CM use to Indigenous cancer patients across these 4 countries; we identified multiple perceived spiritual, emotional and cultural benefits to its use. The patient’s perception of their health professional’s attitudes toward T&CM in some cases hindered or encouraged the patient’s disclosure. Additional research is required to further explore the use and disclosure of T&CM among Indigenous cancer patients to help inform and ensure effective, safe, coordinated care for Indigenous cancer patients that relies on shared open decision making and communication across patients, communities, and providers
Revenue Management of Reusable Resources with Advanced Reservations
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137568/1/poms12672_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137568/2/poms12672.pd
Fluctuation force exerted by a planar self-avoiding polymer
Using results from Schramm Loewner evolution (SLE), we give the expression of
the fluctuation-induced force exerted by a polymer on a small impenetrable
disk, in various 2-dimensional domain geometries. We generalize to two polymers
and examine whether the fluctuation force can trap the object into a stable
equilibrium. We compute the force exerted on objects at the domain boundary,
and the force mediated by the polymer between such objects. The results can
straightforwardly be extended to any SLE interface, including Ising,
percolation, and loop-erased random walks. Some are relevant for extremal value
statistics.Comment: 7 pages, 22 figure
Scaling of waves in the Bak-Tang-Wiesenfeld sandpile model
We study probability distributions of waves of topplings in the
Bak-Tang-Wiesenfeld model on hypercubic lattices for dimensions D>=2. Waves
represent relaxation processes which do not contain multiple toppling events.
We investigate bulk and boundary waves by means of their correspondence to
spanning trees, and by extensive numerical simulations. While the scaling
behavior of avalanches is complex and usually not governed by simple scaling
laws, we show that the probability distributions for waves display clear power
law asymptotic behavior in perfect agreement with the analytical predictions.
Critical exponents are obtained for the distributions of radius, area, and
duration, of bulk and boundary waves. Relations between them and fractal
dimensions of waves are derived. We confirm that the upper critical dimension
D_u of the model is 4, and calculate logarithmic corrections to the scaling
behavior of waves in D=4. In addition we present analytical estimates for bulk
avalanches in dimensions D>=4 and simulation data for avalanches in D<=3. For
D=2 they seem not easy to interpret.Comment: 12 pages, 17 figures, submitted to Phys. Rev.
the SDSS-III APOGEE Spectral Line List for H-Band Spectroscopy
We present the H-band spectral line lists adopted by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). The APOGEE line lists comprise astrophysical, theoretical, and laboratory sources from the literature, as well as newly evaluated astrophysical oscillator strengths and damping parameters. We discuss the construction of the APOGEE line list, which is one of the critical inputs for the APOGEE Stellar Parameters and Chemical Abundances Pipeline, and present three different versions that have been used at various stages of the project. The methodology for the newly calculated astrophysical line lists is reviewed. The largest of these three line lists contains 134,457 molecular and atomic transitions. In addition to the format adopted to store the data, the line lists are available in MOOG, Synspec, and Turbospectrum formats. The limitations of the line lists along with guidance for its use on different spectral types are discussed. We also present a list of H-band spectral features that are either poorly represented or completely missing in our line list. This list is based on the average of a large number of spectral fit residuals for APOGEE observations spanning a wide range of stellar parameters.Alfred P. Sloan FoundationNational Science FoundationU.S. Department of Energy Office of ScienceJanos Bolyai Research Scholarship of the Hungarian Academy of SciencesSpanish Ministry of Economy and Competitiveness AYA-2011-27754, AYA-2014-58082-PRSF 14-50-00043McDonald Observator
Prevalence of Pretransition Disordering in the Rutile-to-Cacl2 Phase Transition of Geo2
The ability to tailor a material\u27s electronic properties using density driven disordering has emerged as a powerful route to materials design. The observation of anomalous structural and electronic behavior in the rutile to CaCl2 phase transition in SnO2 led to the prediction that such behavior is inherent to all oxides experiencing such a phase transition sequence [Smith et al., J. Phys. Chem. Lett. 10, 5351 (2019)1948-718510.1021/acs.jpclett.9b01633]. Here, the ultrawide band gap semiconductor GeO2 is confirmed to exhibit anomalous behavior during the rutile to CaCl2 phase transition. A phase pure rutile GeO2 sample synthesized under high-pressure, high-temperature conditions is probed using synchrotron diffraction and x-ray and optical spectroscopy under high pressure conditions. Density functional theory calculations show that the enthalpic barrier to displacing an oxygen along the B1g librational mode decreases with pressure leading up to the rutile to CaCl2 phase transition. The band structure of the distorted state shows that such oxygen displacements form small polarons
Frequency of Debris Disks around Solar-Type Stars: First Results from a Spitzer/MIPS Survey
We have searched for infrared excesses around a well defined sample of 69 FGK
main-sequence field stars. These stars were selected without regard to their
age, metallicity, or any previous detection of IR excess; they have a median
age of ~4 Gyr. We have detected 70 um excesses around 7 stars at the 3-sigma
confidence level. This extra emission is produced by cool material (< 100 K)
located beyond 10 AU, well outside the ``habitable zones'' of these systems and
consistent with the presence of Kuiper Belt analogs with ~100 times more
emitting surface area than in our own planetary system. Only one star, HD
69830, shows excess emission at 24 um, corresponding to dust with temperatures
> 300 K located inside of 1 AU. While debris disks with Ld/L* > 10^-3 are rare
around old FGK stars, we find that the disk frequency increases from 2+-2% for
Ld/L* > 10^-4 to 12+-5% for Ld/L* > 10^-5. This trend in the disk luminosity
distribution is consistent with the estimated dust in our solar system being
within an order of magnitude, greater or less, than the typical level around
similar nearby stars.Comment: 11 figure
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