5,343 research outputs found
The Divine Clockwork: Bohr's correspondence principle and Nelson's stochastic mechanics for the atomic elliptic state
We consider the Bohr correspondence limit of the Schrodinger wave function
for an atomic elliptic state. We analyse this limit in the context of Nelson's
stochastic mechanics, exposing an underlying deterministic dynamical system in
which trajectories converge to Keplerian motion on an ellipse. This solves the
long standing problem of obtaining Kepler's laws of planetary motion in a
quantum mechanical setting. In this quantum mechanical setting, local mild
instabilities occur in the Kelperian orbit for eccentricities greater than
1/\sqrt{2} which do not occur classically.Comment: 42 pages, 18 figures, with typos corrected, updated abstract and
updated section 6.
Chinese Characters Confirm Genesis Human Creation
Careful analysis of the most ancient extant Chinese pictographic character writing, found on bronzeware vessels and oracle bone artifacts, reveals identical narratives in ideographic characters to that found in the first three chapters of the Biblical Genesis. This second Genesis from a widely separated area of the world. gives added credibility to the human creation epic, as related by Moses.(1
A Postglacial Pollen Record from Western Kodiak Island, Alaska
Excavation of organic deposits in a seasonally dry depression atop a moraine crest near the village of Karluk, on the west side of Kodiak Island, has provided a more detailed paleoenvironmental record than hitherto available for this part of the island. Radiocarbon dating indicates that the base of the section is approximately 4260 14C years in age. Seven minor volcanic ashes are recognized prior to the onset of seasonal drying of the basin at about 2330 B.P. A major ash fall (2 cm thick in section) is recorded at about 1625 B.P. The only significant woody taxon indicated in the pollen record is alder (Alnus); all other important taxa are herbaceous. This vegetation record indicates alders and ferns dominated the landscape immediately following substrate stabilization, which apparently was delayed in this area until well into the Holocene. Alder became relatively less important as soils matured and other taxa (mostly grasses) invaded. The overall record is one of vegetational and climatic stability since landscape stabilization in this area. Volcanic ashfalls have apparently had no significant long-term impact on the vegetation at the site.Key words: Alaska, Holocene, Karluk, Kodiak Island, Quaternary, geology, glaciation, paleoenvironments, palynology, radiocarbon dating, tephraMots clés: Alaska, holocène, Karluk, île Kodiak, quaternaire, géologie, glaciation, paléoenvironnements, palynologie, datation au radiocarbone, cendres volcanique
IMPACT OF MEAT IMPORTS ON LEAST-COST UNITED STATES BEEF PRODUCTION
International Relations/Trade,
Design considerations for CELT adaptive optics
California Institute of Technology and University of California have begun conceptual design studies for a new telescope for astronomical research at visible and infrared wavelengths. The California Extremely Large Telescope (CELT) is currently envisioned as a filled-aperture, steerable, segmented telescope of approximately 30 m diameter. The key to satisfying many of the science goals of this observatory is the availability of diffraction-limited wavefront control. We describe potential observing modes of CELT, including a discussion of the several major outstanding AO system architectural design issues to be resolved prior to the initiation of the detailed design of the adaptive optics capability
Comparing the utilization and cost of health services between veterans experiencing brief and ongoing episodes of housing instability
Housing instability is associated with costly patterns of health and behavioral health service use. However, little prior research has examined patterns of service use associated with higher costs among those experiencing ongoing housing instability. To address this gap, we compared inpatient and outpatient medical and behavioral health service utilization and costs between veterans experiencing brief and ongoing episodes of housing instability. We used data from a brief screening instrument for homelessness and housing instability that has been implemented throughout the US Department of Veterans Affairs (VA) health care system to identify a national sample of veterans experiencing housing instability. Veterans were classified as experiencing either brief or ongoing housing instability, based on two consecutive responses to the instrument, and we used a series of two-part regression models to conduct adjusted comparisons of costs between veterans experiencing brief and ongoing episodes of housing instability. Among 5794 veterans screening positive for housing instability, 4934 (85%) were experiencing brief and 860 (15%) ongoing instability. The average total annual incremental cost associated with ongoing versus brief episodes of housing instability was estimated at $7573, with the bulk of this difference found in inpatient services. Cost differences resulted more from a higher probability of service use among those experiencing ongoing episodes of housing instability than from higher costs among service users. Our findings suggest that VA programmatic efforts aimed at preventing extended episodes of housing instability could potentially result in substantial cost offsets for the VA health care system.This study was supported by funding from the Department of Veterans Affairs (VA) Health Services Research & Development (HSR&D) grant IIR 13-334-3 and from the VA National Center on Homelessness Among Veterans
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Monitoring What Governments “Give for” and “Spend on” Vaccine Procurement: Vaccine Procurement Assistance and Vaccine Procurement Baseline
Background: The Global Vaccine Action Plan will require, inter alia, the mobilization of financial resources from donors and national governments – both rich and poor. Vaccine Procurement Assistance (VPA) and Vaccine Procurement Baseline (VPB) are two metrics that could measure government performance and track resources in this arena. VPA is proposed as a new subcategory of Official Development Assistance (ODA) given for the procurement of vaccines and VPB is a previously suggested measure of the share of Gross Domestic Product (GDP) that governments spend on their own vaccine procurement. Objective: To determine realistic targets for VPA and VPB. Methods: Organization for Economic Co-Operation and Development (OECD) and World Bank data for 2009 were analyzed to determine the proportions of bilateral ODA from the 23 Development Assistance Committee (DAC) countries disbursed (as % of GDP in current US7.61 billion and 0.02% of the GDP of the poorest 117 countries was US$2.88 billion. Conclusions: Adopting 0.02% GDP as minimum targets for both VPA and VPB is based on realistic estimates of what both developed and developing countries should spend, and can afford to spend, to jointly ensure procurement of vaccines recommended by national and global bodies. New OECD purpose codes are needed to specifically track ODA disbursed for a) vaccine procurement; and b) immunization programs
Langevin Thermostat for Rigid Body Dynamics
We present a new method for isothermal rigid body simulations using the
quaternion representation and Langevin dynamics. It can be combined with the
traditional Langevin or gradient (Brownian) dynamics for the translational
degrees of freedom to correctly sample the NVT distribution in a simulation of
rigid molecules. We propose simple, quasi-symplectic second-order numerical
integrators and test their performance on the TIP4P model of water. We also
investigate the optimal choice of thermostat parameters.Comment: 15 pages, 13 figures, 1 tabl
Structure of permethyltantalocenephenylmethanecarbothialdehyde hydride, (η^5-C_5Me_5)_2Ta(η^2-SCHCH_2C_6H_5)H
Hydridobis( 7] 5-pentamethylcyclopentadienyl)
(phenylmethanecarbothialdehyde-kC,kS)tantalum C_(28)H_(39)STa, Mr= 588.63, monoclinic, P2_1 c, ɑ = 15.729 (5), b = 10.203 (2), c = 17.599 (5) Å, β = 116.18 (2)º , v = 2535 (1) Å^3, z = 4, D_x = 1.54 g cm^(-3), λ(Mo Kɑ) = 0.71073 A, μ = 46.6 cm^(-1), F(000) = 1184, room temperature (297 K), R = 0.068 for 2333 reflections with F_o^2 > 0, R = 0.054 for 2179 with F_o^2 > 3σ(F_o^2). The structure is disordered, with two enantiomeric molecules
occupying the same crystallographic site. For the major component, the thioaldehyde ligand has an S-C bond length of 1.86 (2) Å. The ligand is bonded to the Ta center with a Ta-S bond distance of 2.418 (9) Å and a Ta-C bond distance of 2.28 (2) Å
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