198 research outputs found

    Improved Nonrelativistic QCD for Heavy Quark Physics

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    We construct an improved version of nonrelativistic QCD for use in lattice simulations of heavy quark physics, with the goal of reducing systematic errors from all sources to below 10\%. We develop power counting rules to assess the importance of the various operators in the action and compute all leading order corrections required by relativity and finite lattice spacing. We discuss radiative corrections to tree level coupling constants, presenting a procedure that effectively resums the largest such corrections to all orders in perturbation theory. Finally, we comment on the size of nonperturbative contributions to the coupling constants.Comment: 40 pages, 2 figures (not included), in LaTe

    Total Coal Thickness of the Fire Clay and Fire Clay Rider Coals in Eastern Kentucky

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    This map is one of a series that shows the regional characteristics of the Fire Clay coal zone. The maps were prepared as part of the U.S. Geological Survey\u27s National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. Within the zone, the Fire Clay coal is the most economically important bed and is one of the leading producers in the state of Kentucky. It is known for a persistent flint-clay parting that is believed to be of volcanic origin. This map represents the total coal thickness, minus partings, of the Fire Clay and Fire Clay rider coals for the eastern Kentucky region

    Neuroinflammation, Mast Cells, and Glia: Dangerous Liaisons

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    The perspective of neuroinflammation as an epiphenomenon following neuron damage is being replaced by the awareness of glia and their importance in neural functions and disorders. Systemic inflammation generates signals that communicate with the brain and leads to changes in metabolism and behavior, with microglia assuming a pro-inflammatory phenotype. Identification of potential peripheral-to-central cellular links is thus a critical step in designing effective therapeutics. Mast cells may fulfill such a role. These resident immune cells are found close to and within peripheral nerves and in brain parenchyma/meninges, where they exercise a key role in orchestrating the inflammatory process from initiation through chronic activation. Mast cells and glia engage in crosstalk that contributes to accelerate disease progression; such interactions become exaggerated with aging and increased cell sensitivity to stress. Emerging evidence for oligodendrocytes, independent of myelin and support of axonal integrity, points to their having strong immune functions, innate immune receptor expression, and production/response to chemokines and cytokines that modulate immune responses in the central nervous system while engaging in crosstalk with microglia and astrocytes. In this review, we summarize the findings related to our understanding of the biology and cellular signaling mechanisms of neuroinflammation, with emphasis on mast cell-glia interactions

    Searching for a Stochastic Background of Gravitational Waves with LIGO

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    The Laser Interferometer Gravitational-wave Observatory (LIGO) has performed the fourth science run, S4, with significantly improved interferometer sensitivities with respect to previous runs. Using data acquired during this science run, we place a limit on the amplitude of a stochastic background of gravitational waves. For a frequency independent spectrum, the new limit is ΩGW<6.5×105\Omega_{\rm GW} < 6.5 \times 10^{-5}. This is currently the most sensitive result in the frequency range 51-150 Hz, with a factor of 13 improvement over the previous LIGO result. We discuss complementarity of the new result with other constraints on a stochastic background of gravitational waves, and we investigate implications of the new result for different models of this background.Comment: 37 pages, 16 figure

    Quantum state preparation and macroscopic entanglement in gravitational-wave detectors

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    Long-baseline laser-interferometer gravitational-wave detectors are operating at a factor of 10 (in amplitude) above the standard quantum limit (SQL) within a broad frequency band. Such a low classical noise budget has already allowed the creation of a controlled 2.7 kg macroscopic oscillator with an effective eigenfrequency of 150 Hz and an occupation number of 200. This result, along with the prospect for further improvements, heralds the new possibility of experimentally probing macroscopic quantum mechanics (MQM) - quantum mechanical behavior of objects in the realm of everyday experience - using gravitational-wave detectors. In this paper, we provide the mathematical foundation for the first step of a MQM experiment: the preparation of a macroscopic test mass into a nearly minimum-Heisenberg-limited Gaussian quantum state, which is possible if the interferometer's classical noise beats the SQL in a broad frequency band. Our formalism, based on Wiener filtering, allows a straightforward conversion from the classical noise budget of a laser interferometer, in terms of noise spectra, into the strategy for quantum state preparation, and the quality of the prepared state. Using this formalism, we consider how Gaussian entanglement can be built among two macroscopic test masses, and the performance of the planned Advanced LIGO interferometers in quantum-state preparation

    Coal Resources of the Fire Clay Coal Zone in Eastern Kentucky

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    This chart is one of a series that shows the regional characteristics of the Fire Clay coal zone. The maps and charts were prepared as part of the U.S. Geological Survey\u27s National Coal Assessment Program, which compiles regional maps and databases that provide a comprehensive assessment of the most important coal beds in the nation. Within this coal zone, the Fire Clay coal is the most economically important bed and is one of the leading producers in the state of Kentucky. The Fire Clay coal contains a flint-clay parting that is believed to be of volcanic origin. The widespread occurrence of this parting aids in correlation, and therefore the Fire Clay coal is a key marker bed in the region. This chart describes the distribution of data used for the coal assessment, generalized mined-out areas in relation to coal thickness, geologic structure of the bed, and coal-resource estimates. Coal thickness for the Fire Clay and Fire Clay rider beds is presented in Kentucky Geological Survey Map and Chart Series 5 (series 12)

    Up Rising:Rehabilitating J.G. Ballard’s High-Rise with R.D. Laing and Lauren Berlant

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    High-Rise by J.G. Ballard intriguingly contains a pivotal character named Dr. Robert Laing, surely an allusion to the then influential psychiatric writer, Dr. R.D. Laing. Re-reading Ballard's classic text through the prism of Laing’s theories, with further explication of the role of flat affect via Lauren Berlant, this article presents a new interpretation of a classic text that argues that Ballard ingeniously misdirected his readers into making identifications with precisely the wrong characters and the wrong actions. Re-focusing a subject gaze in accordance with these theoretical analyses, allows for an entirely alternative understanding of the text in which Ballard was more than a pessimistic prophet of inexorable urban breakdown, he foretold societal rehabilitation as well. High-Rise is read as a classic of psychogeography, an established genre which is argued to be of great relevance to the study of society and space. This article therefore engages in a reading of a psychogeographical text via theory implicitly alluded to by the text itself

    Forty years of carabid beetle research in Europe - from taxonomy, biology, ecology and population studies to bioindication, habitat assessment and conservation

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    Volume: 100Start Page: 55End Page: 14
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